A wide range of study designs are used in nutrition research, and no single study design can answer every question ².  Understanding the purpose, strengths, and limitations of each approach helps distinguish between stronger and weaker evidence, so the hierarchy of research methods is key to evaluating the quality of evidence.

This article outlines the key study designs used in nutrition research, the types of questions they are best suited to answer, and the strengths and limitations that guide how their findings should be interpreted, based on several resources ^1-5.

Visualising study designs as a pyramid (Figure 1) highlights how evidence strength varies.  Studies at the lower levels of the pyramid tend to offer limited, less practical insights, while those at the top delivering stronger evidence with greater relevance to real world nutrition choices ^3,4.

Figure 1.  The hierarchy of evidence ranks different types of research according to the strength of the conclusions ³.  (Licensed under CC BY 4.0)

Systematic reviews and meta analyses sit at the top of this hierarchy because they provide data across multiple studies to provide more comprehensive conclusions.  Randomised controlled trials and prospective cohort studies typically provide the most robust evidence when examining relationships between dietary exposures and health outcomes.  However, the rapid growth of the field — and the diversity of methods used — can make it challenging for practitioners and consumers to interpret findings and translate them into practice.

Foundational Research: Non-Human Studies

Foundational research — including in vitro studies in cells or tissues and in vivo studies in animal models — plays a critical role in uncovering the biological mechanisms that underpin how nutrients, ingredients, and other food components behave in controlled settings.  These early stage studies provide directional evidence that helps shape hypotheses and supports the rationale for human research.

It is important to note that isolated cells and tissues and animals do not replicate the complexity of human physiology.  Differences in metabolism, exposure levels, and biological responses mean that findings cannot be directly translated to human outcomes.  For instance, a compound that influences cellular metabolism in vitro, for example, may behave very differently within the interconnected systems of the human body.

However, the value of foundational research becomes clear when it is integrated with human data.  For example, while observational research links smoking with cancer, cell studies identify the carcinogenic compounds responsible.  So, when mechanistic evidence aligns with human outcomes, confidence in the overall conclusion(s) is strengthened.

Observational Studies

These studies track large groups of people over time, in real-world settings, to understand how lifestyle behaviours — including dietary patterns — relate to health outcomes.  These studies identify population level patterns and provide potential associations that may warrant further investigation in more controlled study designs.  Observational studies cannot determine cause and effect relationships and, hence, the impact of a single dietary or lifestyle factor.

Common observational designs include prospective cohort studies, case–control studies, and cross sectional studies, each offering different strengths for understanding how diet and lifestyle influence long term health.

Case Control Studies

Case control studies compare people who already have a specific health condition (the cases) with similar individuals who do not (the controls).  Researchers then look back in time to assess whether past exposures — such as dietary habits — differ between the two groups.  For example, comparing fruit and vegetable intake in people with and without heart disease may help identify potential associations with disease risk.

These studies are relatively quick and cost effective, making them especially useful for investigating rare conditions or outcomes that would be difficult to study prospectively.  They can also examine multiple potential risk factors at once and often serve as an important first step in identifying associations that warrant further research.

However, case control studies face several methodological challenges.  Because exposure information is collected retrospectively, they are highly susceptible to recall bias — particularly when individuals with a disease remember past behaviours differently from those without it.  Selection bias, confounding, and reverse causation can also limit the strength of conclusions.  For instance, if higher consumption of non sugar sweeteners is observed among people with obesity, it may reflect dietary changes made after weight gain rather than a causal effect of sweeteners.

Cohort Studies

Cohort studies are observational studies that are either prospective or retrospective, depending on when the data were collected.  In a prospective cohort, participants complete questionnaires and undergo measurements at the start of the study.  On the other hand, with retrospective cohort studies, researchers “look back” to analyse the relationship.

Prospective cohort studies follow large groups of people in real world conditions over many years — sometimes decades — to explore how dietary and lifestyle exposures relate to the development of diseases.  Participants provide information at baseline and at regular intervals on factors such as diet, physical activity, and health status.  Dietary intake is usually self reported, which introduces challenges such as misreporting, difficulty estimating portion sizes, and changes in behaviour over time.

By tracking outcomes over time, researchers can examine patterns and test hypotheses.  Collectively, prospective cohort studies have shaped much of our understanding of how diet and lifestyle influence chronic disease risk, such as cardiovascular disease or osteoporosis.  However, their long duration means they are time and resource intensive.  As with all observational research, these studies can identify associations but cannot establish cause and effect relationships.

Cross Sectional Studies

This type of research provides a snapshot of health behaviours, exposures, and outcomes in a population at a single point in time.  They are typically conducted through surveys or brief assessments that collect information on both potential risk factors and health indicators simultaneously.

However, cross sectional research has important limitations.  Because exposure and outcome are measured at the same moment, it is not possible to determine which came first.  This raises the issue of reverse causality — for example, whether a dietary behaviour contributes to a health outcome or whether the health outcome influences how participants report their diet.  Cross sectional studies can also be affected by selection bias and recall bias, particularly when participants’ awareness of their health status shapes how they report past behaviours.

Despite these constraints, cross sectional studies are cost effective, relatively quick to conduct, and useful for estimating the prevalence of dietary habits, lifestyle behaviours, or health conditions in a population.  They can also highlight potential associations worth exploring in more rigorous study designs.  A typical cross sectional study might compare dietary patterns across countries to explore whether differences in diet align with variations in cardiovascular disease prevalence.

Randomised Controlled Trials (RCTs)

Randomised controlled trials (RCTs) are considered the gold standard for determining cause and effect relationships ^1,2,5.  Participants are recruited and randomly assigned to a control (placebo) group or an intervention group, ensuring the groups are comparable at baseline.  For example, in an RCT examining the Mediterranean diet and cardiovascular risk, the control group might follow a standard low fat diet while the intervention group adopts a Mediterranean pattern ³.  After a defined study period, researchers compare outcomes such as heart attacks or strokes between groups. Because randomisation minimises confounding factors, differences in outcomes can be attributed to the intervention itself.  This is why RCTs provide the strongest evidence for causation rather than correlation. When conducted as double blind trials, neither participants nor researchers know who receives the treatment, further reducing bias and mitigating placebo effects.

Despite their strengths, RCTs come with practical and ethical constraints.  They are expensive, often involve small sample sizes, and may struggle with long term adherence, especially when testing complex dietary patterns.  Ethical considerations limit the ability to test harmful exposures or withhold beneficial treatments.

Systematic Reviews and Meta Analyses

Systematic reviews and meta analyses sit at the top of the evidence hierarchy because they provide a comprehensive overview of existing evidence and can reveal whether findings are consistent across different populations and settings. However, these methods are only as strong as the quality and consistency of the studies they include, and ensuring relevant studies are not missed or intentionally excluded.

However, these methods are only as robust as the quality and consistency of the studies they include, and they rely on thorough, unbiased inclusion of all relevant evidence.

A systematic review uses a structured, transparent process to identify, evaluate, and summarise all relevant research on a specific question. When the included studies are sufficiently similar in design, population, and outcomes, researchers may conduct a meta analysis, which statistically pools results to generate a single, weighted estimate of effect. Larger, well designed studies contribute more heavily to this estimate than smaller or lower quality studies.

Systematic reviews and meta analyses help determine whether scientific findings are consistent, generalisable, and reliable, and they often guide policy decisions, clinical recommendations, and future research priorities.

In Summary

Science is a continuous process.  It can move slowly and often involves uncertainty, yet it remains the most reliable way to build understanding about the world and human health.  Many types of studies contribute to this evidence base, each with its own strengths and limitations, and no single study provides a definitive answer.  Progress happens because researchers continually evaluate and refine one another’s work, identifying opportunities to improve methods and explore new questions.

On October 15^th, 2024 experts gathered for an informative webinar exploring Taste Modulation and how it can be used to support positive nutrition. You can watch this full webinar by clicking the video above!

David Deeley (Sr. Insights Manager, Kerry) begins the webinar (at 1:29) highlighting the importance of the consumers’ needs and wants in an ever-evolving world of human nutrition. With upwards of 49% of consumers desiring science-backed ingredients, industry leaders need to create functional products that provide health benefits to the consumer.
Using the concept of “Vitality Unlocked” (at 8:18), David explains how consumer behaviour has evolved significantly. He went on to explain the three categories that make up this concept as well as real-life industry examples:

1. Blurred Lines (at 10:48)– how the line between dietary supplements and traditional food and beverage are increasingly blurred.
2. Functional Pleasure (at 12:39)– how consumers are looking to implement functionality to indulgency.
3. Personalised Therapy (at 14:57)– the need for instant gratification and on-demand functional therapy.

In today’s market, consumers are now less fearful of illness and are more price sensitive. Despite this, they continue to purchase health and wellness products, often willing to trade up for quality over the lowest-priced options. Beyond the health benefits, 59% consumers also want products that taste good. This demonstrates that consumers are not willing to compromise on taste. This poses a unique challenge for the industry: How can food, beverage, and supplement producers add the functionality without sacrificing on taste? The answer is the science of Taste Modulation.

Dr. Alex Woo (Founder and CEO of W2O Food Innovation) dives deeper (at 20:56) into what taste modulation is and how our bodies perceive taste. The technology is used to either increase, decrease, or modify taste detection at the receptor level or in the brain’s perception. Dr. Woo highlights four main methods of taste modulation:

1. Sweetness Modulation (at 23:44) – explaining how sweeteners bind to locations on receptors and influence perception. He also highlights seven key types of modulators.
2. Salty, Umami, and Kokumi modulation (at 27:46) – explores saltiness and how to make product products taste saltier without adding more salt (negatively impacting nutrition).
3. Supplements and Alcohol Modulation (at 30:31) – delves into how to utilize taste modulation for supplements that may cause off-odours, off-taste, and off-mouthfeel. Additionally, covering off on how to recreate the alcohol taste/feel for zero and low alcohol beverages.
4. Bitterness Blockers (at 32:51) – which deep dives into how our body detects/perceives bitterness and what types of modulators can be used to block this.

Dr. Woo finishes his section (at 37:00) highlighting the importance of taste modulation for the future of the food industry and how scientists will need to utilize this to ensure foods, beverages, and supplements are delivering positive nutrition to consumers.

Katherine Ceschi (Sr. Scientist for Taste Innovation, Kerry) closed out the webinar (at 38.45) discussing practical applications for the use of taste modulation. Through her work she was able to discuss three successful case studies in which she was able to utilize different taste modulation techniques to enhance products nutritionally, as well as support the need for sustainable practices:

1. Addressing salt enhancement through molecular techniques (at 40:33)
2. Utilizing Waste Streams by repurposing spent coffee grounds to mask bitterness. (at 44:31)
3. Mimicking Animal fat to create a sustainable, vegan, and regulatory friendly taste modulator (at 47:32)

Finally, ending the webinar was a lively Q&A session (at 51:42) where viewers were able to ask questions such as how consumer perceptions have changed over the years, specifics on taste modulation compounds, and further questions regarding the case study.

From this webinar, it’s clear that as consumer knowledge on nutrition continues to expand, the expectation for nutritious food with great taste and flavour also rises. At the same time, sustainability and market trends continue to drive innovation and set the stage for the future of nutrition, demonstrating the essential need for taste modulation.

To stay up to date on topics like Taste Modulation and the future of positive nutrition, be sure to subscribe to KHNI!

]]> https://khni.kerry.com/articles/food-science/novel-methods-for-precision-shelf-life-optimisation-in-meat/ Sun, 18 Aug 2024 21:11:53 +0000 https://khniuat.kerry.com/?p=27885 ... Read more »]]> Can you quantify the value of extra shelf-life days in food?

As a consumer, it can allow for more time in a busy life to eat foods before they end up as unintended waste.  This time can be about saving money and protecting health.

For the industry, it can be about longer and more resilient supply chains, as well as insurance policies against spoilage and contamination risks.

For brands, extending freshness increases brand loyalty and their ability to delight consumers.

For the planet, it’s stretching the planet’s resources so we can feed more people and reduce the contribution of greenhouse gases from food waste.

One third of all food produced globally goes to waste which has a huge impact on the sustainability and economics of food production and consumption.  With inflation soaring and supply chain pressures growing, it’s never been more important to prevent this.

Seventy-two percent of consumers agree that extending the shelf life of a food or drink would help them reduce waste.  Given that up to half of consumer food waste could be prevented by shelf-life extension, it is a great place to start.

How do we approach a project about shelf-life extension, or problem solve for an unknown shelf-life limiting factor?

To extend shelf life, scientists will need to look at which exact bacteria are contributing to spoilage defects, also known as “specific spoilage organisms”.  While these strains may seem invisibly small, they leave behind evidence as to which microbial culprits are responsible for food spoilage.  Often, these clues come in the form of the product defects themselves, so discussing with a processor what is happening in their product, or directly observing it in the laboratory can start the investigation.  Different microbiomes produce volatiles because of their metabolic activities, so organoleptic evaluation can help understand the system.  For example, lactic acid bacteria can often ferment sugars, making sulfuryl/sour off-odours, while pseudomonads are known for their floral/fruity ketones and alcohols.  Beyond odour, some bacteria leave “footprints” behind in the form of slime (often seen with Leuconostoc contamination) or colour changes.

In other cases, the microbiome may be made of a dynamic mix of genera, with many spoilage defects, complicating the mystery, or they could be in an emerging system with an under-profiled microbiome, such as plant-based meat alternatives.  In these systems, scientists can directly catch the microbial suspects through their DNA, rather than sifting through clues.  Rather than isolating one organism at a time, scientists can now extract all the DNA from a sample and sequence it, revealing the “group photo” of who is present at the spoilage crime scene.  If a particular sequence of DNA is found in high abundance, it could be possible that the culprit has been found, and scientists can get to work isolating it to prove it responsible.

Relative abundance (proportion) of (a) family and (b) genus classification of bacterial community according to brand of sliced, pre-packaged deli ham.  The top 24 most prevalent genus according to maximum relative abundance across all 3 treatments are represented.

From the sights, smells, and sequencing activities, scientists know which strains are present, and can pick the right media to isolate them from the food matrix.  Different bacteria have different preferences for nutrients, so knowing the strain makes it easier to pick or develop their preferential media for culturing.  Once the strains are cultured, they can be reintroduced into a food matrix to make sure they exhibit the defect of concern to implicate their role in spoilage, as well as compare them to other strains in challenge testing.  The specific spoilage organism has been caught, so solutions can now be tested.

Second step: “Precision Shelf-Life Extension”

Once the microorganism is known, scientists can be more specific about the different factors that have enabled it to grow, as well as the hurdles that can be put in its way.  A favourite way to simplify well-known concepts surrounding microbiology for the less familiar is to compare them to all the (intrinsic, extrinsic, and implicit) factors that would contribute to a child growing and thriving in school, across their environment, diet, comfort, energy inputs into other areas and to leverage hurdles that may prevent that growth.

Bacteria have personalities, patterns and some predictable responses, so scientists can leverage reference literature, or previously conducted work with similar strains to assess which solutions may work best.

Just as people go to the doctor to know which medicine can best help their problem, microbiologists seek to give a precise solution as well.

For example, Pseudomonas spp. are generally known, and internally tested to be sensitive to organic acid solutions.  In this case, vinegar may be appropriate.  Certain lactic acid bacteria however, as their name suggests, produce lactic acid, and thus can be more resistant to organic acids as solutions.

In these cases, scientists will need to layer in solutions with different or multiple modes of action, that are designed to inhibit these robust strains.  It is not usually just one strain in a product microbiome.  Some bacteria can tolerate stress much more readily than others, so ensuring a diverse array of strains is used for shelf-life testing can lead to the development robust solutions that work against a broad spectrum of microbiomes.

Ingredients, bacteria and people do not always behave the same in various groups as they do in isolation.  This again is why testing with layered ingredients and multiple strains will dramatically improve the replicability of any inoculated tests, out in the real world.  Single ingredients that have limited efficacy on their own may become superheroes against stubborn bacteria when they have an organic acid present to fight off the usual suspects.

For meat processors, this is of great importance, as formulas can be produced by co-manufacturers in facilities with different microbiomes, or ingredients such as spice blends could change, bringing in different organisms.  Through knowing your microbial enemy, shelf-life extension is possible.

The most common methods include the use of various anti-Listeria ingredients, higher levels of sanitation, and high-pressure processing (HPP). During HPP, the food product, encased in its package, is subjected to ultra-high pressure for a specific period of time. The high pressure is sufficient to inactivate various bacteria, including Listeria, without compromising the nutritional value and quality of the food product. The HPP process has been used for many years by several large meat processors in the USA and is a proven non-thermal technology that does not change the ingredient profile of the food product. Typically, packages of the product are placed into the HPP vessel filled with water where the pressure is increased to about 87,000 psi for around three minutes, then the pressure is released. The whole process including the time to come to pressure, hold, and decompress takes approximately 10 minutes per batch.

High Pressure Processing (HPP) is good, but has practical limitations

There are many aspects of HPP that offer unique benefits through its use. However, its impact of sustainability over ingredient processing could be significant.

What are other options to HPP?

Fortunately, Listeria is sensitive to weak organic acids; consequently, ingredient interventions containing such compounds/chemicals have been found to inhibit the growth of Listeria throughout the whole shelf life of the product, even after package opening. These weak organic acids include vinegar (acetic acid), potassium and sodium lactate, sodium diacetate, and other versions thereof. Many of these ingredients are produced from various fermentations and result with the inclusion of some anti-Listeria peptides as well. An ingredient solution may also provide a more sustainable solution in the production of RTE meat products compared to HPP for several reasons:

• • More sustainable packaging is possible when it does not need to withstand ultra-high pressures.
  • Providing some protection post-opening (secondary shelf life) has the potential to reduce food waste.
  • More streamlined processing lines and reduced potential for bottlenecks and extra transportation.
  • Improved supply chain flexibility for decarbonization.

A unique blend of organic acids and peptides can improve product quality through clean label inhibition of pathogens and spoilage in RTE poultry products. This product can be used in uncured (no added sodium nitrite) and can work in high moisture-containing poultry products. It results in a more natural color and flavor and is efficacious against Listeria, Clostridium perfringens, and Clostridium botulinum as well as some spoilage organisms. The product is labeled as “buffered vinegar and cultured dextrose” which falls into the more “clean label” category. It has a less expensive cost-in-use than HPP. Studies at the Food Research Institute (University of Wisconsin) have shown no growth in Listeria for 14 weeks (1) when used in a low sodium turkey product (76% moisture, pH 6.2, 1.55% salt) when used at a rate of 2.0% (Fig. 1).

In addition to Listeria, this combination was successfully able to control resistant lactic acid bacteria in fresh poultry (2) and beef systems (3).   

   Figure 1: Listeria monocytogenes control with Buffered Vinegar and Cultured Dextrose 

HPP’s Impact on Food Waste

In a case study where HPP-processed meat waste volumes were measured in foodservice and retail deli counter environments. The main sources were from damaged packaging and products that were not consumed/sold in the short shelf-life after opening. The value captured was significant enough to warrant exploring the waste reduction from the secondary shelf-life extension that would occur through the potential replacement of the process with an ingredient-based solution. Add this to the difference in environmental resources required for the ingredient-based approach versus the energy-intensive process and the impact of the switch became compelling (4). The Kerry Food Waste Estimator was used to give an indication of the volumes of waste that would be reduced downstream through the extra days after opening delivered by the switch.

Conclusions

The old saying that one size does not fit all applies to the different anti-Listeria interventions available to meat processors in the production of RTE meat products. Listeria monocytogenes represents a real threat to the safety of consumers. This is because of increased monitoring, sanitation, and the use of effective antimicrobial interventions. Meat processors have the options of various proven interventions including HPP and various ingredients. The choice of which to use depends upon the company’s business goals and food safety philosophy. So, one shoe does not fit all sizes.

Key dietary shifts are emerging through a collaboration of food science and nutrition with the aim to couple reductions in both our carbon footprint and risk of chronic disease, helping to build a sustainable healthy future for us all.  

In 2019, Our World in Data, reported that 74% of global mortality was attributed to chronic disease, with CVD (cardiovascular disease), cancer, and diabetes, being the main contributors.  Our eating habits and the associated increase in obesity worldwide being a primary cause of these statistics.  At the same time, Board Bia share statistics on food waste indicate over one third of all food produced in a year is wasted, contributing to almost 10% of global GHG (greenhouse gas) emissions and losses of €1.2 trillion each year.  This highlights the potential for food science and nutrition in preserving our future, and there are some exciting dietary innovations already out there.   

Nutritional Quality of Berry Fruit 

A shift from western dietary patterns consisting of red meats and processed foods high in saturated fat, sugar, and salt to the flexitarian style diet consisting of whole foods like fruits, vegetables, grains, pulses, and oily fish is becoming increasingly popular.  These are more nutrient-dense high fibre options, but many of these foods contain non-nutrient compounds that have potential health benefits called phytochemicals.  

Regardless of fresh or frozen, in the case of berries, they possess a nutritional edge due to their phytochemical composition which has been quantified in numerous studies (Toledo-Martin et al. 2018 and Ponder et al. 2021).  Phytochemicals such as polyphenols, anthocyanins, stilbenes, and carotenoids along with essential vitamins and minerals are found in common house-hold berries such as blueberries, blackberries, strawberries, and raspberries.  Lesser common berries such as Sea Buckthorn and Mulberry are composed of the same phytochemicals.  These compounds have been shown to have anti-inflammatory and antioxidant properties.  

Berries as Antioxidants 

The high antioxidant activity of berries due to their phytochemical concentration means they help to effectively scavenge unwanted oxidizing radicals from our body.  These oxidizing radicals are thought to be linked to development of different diseases and health conditions, and may be one way berries work to improve health (Soobrattee et al, 2005).  

Heart Health 

Studies have shown phenolics such as ellagic acid present in these berries may protect against atherosclerotic plaque formation in our blood vessels, reducing the risk of hypertension and heart disease (Olas et al. 2008).  In 2015, the PREDIMED study concluded increased polyphenol intakes were associated with reduced blood pressure in trial participants as well as decreased biological markers of inflammation and oxidation, possibly contributing to reduced risk of cardiovascular disease.  

Blood sugar management

Clinical trials in humans have shown the anthocyanins and stilbenes found in these berries may reduce the impact of postprandial hyperglycaemia (sugar spikes after a meal), which could protect cells of the pancreas and liver from oxidative stress and inflammation, leading to a potential reduction in the risk of type 2 diabetes (Blaak et al, 2012). 

Processing and Berry Nutrition Quality  

For many people, fresh berries are the preference when it comes to taste and texture, but these non-climacteric fruits have poor shelf-life.  Within a couple of days to a week, berries enter senescence and mould begins to grow.  For this reason, freshly purchased berries are often thrown in the bin and this is a primary example of the food waste that contributes to significant GHG emissions.  

Food scientists have looked at several berry preservation methods to prolong their naturally short shelf-life, but there is often a caveat associated with the properties of processed food.  

Dried berries 

Thermal processing (dried berries), which aims to reduce the moisture content of the berries, will successfully extend shelf-life but causes leaching of certain nutrients and phytochemicals (Figure 1) which negatively impacts the nutritional value of the berries.

Figure 1. Impact of thermal processing on anthocyanin content of blackberries. (P. Reville et al. University College Cork, 2022).

Juiced Berries 

Juicing berries has also been a successful processing method in extending shelf-life, but this too causes a reduction in desirable phytochemicals such as anthocyanins.  These conventional processing methods are effective, but we need to think outside the box to make our food systems more sustainable.  Shelf-life and nutritional integrity must be optimised.  

Frozen Berries 

Freezing or freeze drying provides fruit and vegetable products with a variety of economic and environmental benefits.  

We don’t have to worry about losing nutritional value if we opt for frozen berries.  Studies have shown berries maintain a complete nutritional profile after freezing (Lohachoompol et al, 2004) unlike other thermal processing methods.  This means shelf-life is improved without compromising nutritional profile which we now know is of great value in berries.  

Economic and Environmental Benefits 

There is no need to bin frozen berries a few days after they’re bought, immediately ruling out food waste.  As well as this, frozen fruit can be, and usually are sold in larger volumes of up to 1kg due to improved stability post freeze-drying, compared to fresh berries which are usually sold in trays of 100g to 300g.  If we were to switch to frozen berries, this would significantly reduce the amount of plastic packaging required which is another crucial aspect of sustainability.  

The fresh berries we buy often contain stems and leaves, otherwise known as ‘cut-offs’.  These cut-offs are usually thrown to waste in the home.  However, innovative industries are now using cut-offs from fruit & vegetables going through the freeze-drying process to generate biogas through anaerobic microbial digestion, providing energy in a circular manner which is further reducing the waste generated from frozen fruit and vegetable production (Carlos Morales-Polo et al, 2019). 

For consumers, there is also economic value to frozen berries.  At one popular international grocery store, fresh berries cost between €10 & €20 per kg compared to frozen berries at approximately €3 per kg, indicating a significant cost-saving associated with frozen berries. 

Freeze drying can strike a balance between sustainability and nutrition, making it a promising tool to consider for the future food system. 

From sweet to sour and salty, bitter to umami, taste perception greatly influences our sensory enjoyment of food. Many of us are familiar with these five primary tastes. However, researchers have highlighted an additional taste sensation known as ‘kokumi’ that may be important in enhancing these other perceptions.  

Kokumi has been part of the Japanese culinary tradition for centuries. It is associated with foods that exhibit a fullness, succulence and craveability. It is derived from ‘koku’ meaning rich and ‘mi’ meaning taste. The kokumi taste sensation can be found in cheese, yeast extracts as well as wine. Garlic has also been mentioned in early kokumi focused research as Ueda et al. reported that water extracts from garlic enhance umami taste intensity (1). Flavour scientists have had increased interest in this area of research, and they are continuing to discover the characteristics of this new taste sensation. 

Information on Kokumi is in demand

How a food tastes is one of the most important aspects when it comes to consumer food choices and preferences (2). This may be a contributing factor to the increased fascination with taste sensation such as kokumi in recent years. Many people are unaware of kokumi, however, foods having a rich texture and comfortable mouthfeel is something we can all relate to. The deep enhancement of flavour encourages consumption, enjoyment and interest in certain foods. This could indicate why information surrounding kokumi is on the rise. 

How is kokumi different to umami? 

Unlike umami, kokumi compounds do not present a flavour attribute in isolation. Umami is a distinct taste perception by itself, and more can be found about it from the Kerry white paper here. Kokumi peptides are known to enhance the umami taste by promoting a roundness and full mouthfeel (3). This means that the two sensations work in tandem to give us both a savoury flavour with lasting richness (4). 

Kokumi is also associated with the ageing and maturation process. It can be found in foods that have a longer preparation time such as slow-cooked stews and fermented foods. Have you noticed that when we let a stew simmer or allow cheese to mature, it takes on a deeper and richer taste (5)? The balance of salt, sweet, sour and umami in these foods is overlayed by kokumi, which gives them a deep taste (6). 

As mentioned before, slowly cooked foods have distinct flavour profiles associated with kokumi. This is caused by the degeneration of proteins that are present. Proteins are made up of amino acids and peptides. Amino acids are the building blocks of protein and these join to make peptide chains (7). 

Like umami, kokumi substances have peptides and amino acids that are associated with it – for instance, glutathione and gamma-glutamyl peptides. These can be found in aged foods such as gouda cheese and fermented foods such as nattō. These foods deliver a round and rich flavour which is characteristic of kokumi (6)(9)(10). During cooking and ageing, kokumi substances are released from these products, providing depth of flavour(8)(9).  

Science of kokumi – how does taste perception work? 

Researchers have noticed that kokumi substance such as GSH (Glutathione) activates the CaSR (Calcium Sensing Receptor). These CaSR belong to the G-protein receptor family and have been found in the lingual tissue of mice. When mixed with other taste stimuli such as umami, sweet and salty, kokumi enhances thickness and continuity(4). 

These kokumi peptides activate the calcium receptors and create a domino effect of sensation. Essentially, the receptors have a high affinity for the peptides responsible for creating a kokumi sensation. Studies have shown that there is a correlation between the amount of calcium-sensing receptor activity and the intensity of richness that we associate with kokumi. However, this remains a new area of neurogastronomy and requires further, in-depth research (11). 

Why kokumi may be important in the future of food: 

As mentioned before, kokumi is known to heighten the savoury and deliciousness associated with umami. Corporations hoping to transform the flavour profile of various foods have harnessed umami and kokumi as flavour solutions to deliver new and exciting tastes to the market. As we shift towards more sustainable food products and clean label solutions, the use of umami and kokumi could be more important.  

Further development into plant-based meal alternatives has grown in recent years, and researchers have discovered that soybean extracts have the potential to be kokumi enhancers in food products. In addition, different flavourings can deliver a savoury sensation comparable to meat products.  This is the case with products such as yeast extract, as it can replicate meaty flavours in plant-based foods. This is a result of key kokumi peptides that are present within yeast extract (8)(9)(12-14). 

The use of yeast extract application in plant proteins is increasing as it solves the challenge of delivering a clean-label solution with rich, juicy meaty taste, based on its natural composition of umami and kokumi.    

With an ageing population, flavourful foods are important to aid with consumption and prevent the adverse health effects of malnutrition. Older persons have a reduced taste perception and often add salt to savoury foods to enhance the flavour, see the KHNI article The Retiring Nature of Taste Perception. This can contribute to high blood pressure and other cardiac issues. There has been increased research into the potential of umami and kokumi flavours to reduce the salt content of foods (15). However, this concept requires further investigation, but could be of interest to those wishing to reduce their salt consumption. 

Conclusion 

There may be potential for kokumi to be a staple taste sensation in future taste solutions. It supports the savoury, delicious and juicy flavours of umami to deliver a balanced, rich, and deep sensation. It could be one of the unsung heroes in taste perception and there is scope for further research and development into its uses. As taste is a key determinant of food enjoyment, scientists continue to uncover novel applications of kokumi and hope to further use its properties. Taste and texture go hand in hand to enhance the culinary experience of food and there is potential for kokumi to contribute further to our enjoyment of delicious taste.

Cultivated meat is expected to be an important contributor towards this progress.  But what is cultivated meat? How will it be important for human progress?  Will it be the same as conventional meat? And when will it be a reality?

What is cultivated meat?

Cultivated meat is defined as the production of muscle and fat tissue from cells that are grown in vitro or outside of a living organism under controlled conditions to yield a protein-rich tissue.  Dating back to 2013, the public first grasped knowledge of cultivated meat when a burger made from cells grown in a laboratory was tasted by a panel of judges on live television.  Prepared by Mark Post’s research group at Maastricht University, this proof of concept took over 5 years and around $300,000 to prepare but showed the world that cultivated meat is possible.

What are the benefits of cultivated meat?

While conventional livestock agriculture will certainly continue to be an important part of the food supply, supplementation with meat from alternative practices, including meat grown from cells, will be inevitable for future human prosperity.  Some of the benefits include:

• • Elimination of animal suffering
  • Shorter time to produce – cells can be grown in a matter of days/weeks vs months/years for traditional farmed meat
  • Eradication of food-borne illnesses and mitigation of antibiotic resistance (Van Boeckel et al, 2017).
  • Lower environmental impacts including greenhouse gas emissions, along with land and water usage (Gerber 2013)

Figure 1. Cultivated meat is estimated to lessen land and water usage with shorter production times.  Data based on using 2900 gallons of water, 1345 square feet of land, and 14 months to produce 1lb of traditionally grown beef.  Reductions based on life-cycle analysis with a reduction in land usage of 99% and water usage of 82% (Tuomisto and Teixeira de Mattos, 2011).  Time to produce cultivated meat based on 45 days from start to harvest (Post, 2020b).

Sustainability and lessened environmental strain are attractive benefits of cultivated meat; the exact impact will depend on the life-cycle of the product.  Outside of terrestrial livestock farming, our oceans are under immense pressure from overfishing and climate change.  Cultivated meat from fish and shellfish offer sustainable options to help lessen the strain on ocean ecosystems.

How is cultivated meat made?

The science of growing the cells and organised tissues for cultivated meat is rooted in cell biology, bioprocessing and tissue engineering.  The first step begins with cell selection and development.  This is critical for the success of cultivated meat since the cells need to grow quickly to high concentrations, be stored and re-used indefinitely, adapted to serum-free media, and differentiate into muscle or fat tissue (Stephens, 2018; Post, 2020a).

In general, cell lines will be created from adult stem cells.  Adult stem cells are different from embryonic stem cells, they can be isolated from a tissue biopsy, a harmless procedure that removes cells from an adult animal.

Next, the chosen cell line is grown under appropriate conditions allowing them to replicate or grow; 0.5g of cells can achieve 2000 kg of meat in 45 days of culturing (Post, 2020b).  This often starts at bench scale using petri dishes or flasks and scaled up to larger, well-controlled bioreactors.  Once the target concentration is reached, the cells undergo differentiation or transition into muscle or fat cells.  The cells can either be harvested in a “free state” or continue to organise into tissues.  Under the appropriate conditions, tissues can be guided towards organised 3D structures of fibres, cartilage, blood vessels using tissue engineering approaches to create a food product like steak, chicken breast, salmon filet, lobster claws, etc.

Is cultivated meat the same as conventionally grown meat?

At the cellular level, cultivated meat is identical to conventionally grown meat.  It isn’t synthetic meat or lab-grown meat but rather is meat grown outside of the animal.  Theoretically, adult stem cells can grow and differentiate into organised tissues that would be identical to a cut of steak, chicken breast, etc.  While this is the ultimate end-goal, minimal viable products (MVP) first entering the marketplace will likely be made from cells harvested as a protein/fat-rich ingredient and formulated with other ingredients into a final meat-based product (Stephens et al., 2018).

Using this approach, integration of food science and cell culture bioprocessing will be key to develop familiar, nutritious products acceptable to consumers.  Considerations for creating cultivated meat products would be ensuring the products have similar sensory properties to existing foods on the market.

From a nutritional standpoint, cultivated meat could be made healthier.  An example would be tailoring the fatty acid profile of fat cells to include polyunsaturated fatty acids or modifying the cell to make antioxidants such as carotenoids (Stout et al., 2020).  Formulating with other ingredients such as plant-based proteins and fats, emulsifiers, stabilisers, and flavours can be used to create acceptable products.  A general overview of the production process is shown in Figure 2 below.

Figure 2. Hypothetical cultivated meat production scheme.  This image is a generalisation and may not reflect the actual technologies and approaches being used for cultivated meat development.

Will it ever be a reality?

In 2013, Mark Post proved that cultivated meat was possible.  Now over 70 start-ups have emerged with greater than $355 million dollars invested and more than 15 cultivated meat products being pursued (Bryne et al. 2020).  With the recent historical commercialization of Eat Just’s GOOD Meat cultured chicken nuggets being sold for ~$20 at 1880 restaurant in Singapore, cultivated meat is now a reality.  This is certainly very exciting but there are still serious challenges that lie ahead.

Consumer acceptance is going to be critical for the success of cultivated meat products (Tomiyama et al, 2020).  Important considerations for consumer acceptance include price, taste and safety (Crosser et al. 2019).  MVPs first entering the market will likely rely on first adopters willing to pay higher prices, open to try novel foods, while late adopters will rely on familiarity once more culturally accepted.

Manufacturing cultivated meat to replace conventionally grown meat will be one of the greatest human achievements to date.  According to some, large scale manufacturing won’t be possible due to many unknowns and costly challenges (Fassler, 2021; Humbird 2021):

• • Proposed scale of production has never been done before
  • Cost and availability of nutrient media and growth factors
  • Novel engineering strategies needed to achieve target cell numbers
  • Prevention of microbial and viral contamination

Historically, cell culture has been used by the pharmaceutical industry to make high-value drugs in limited quantities compared to quantities needed for cultivated meat, which will require a production scale larger than anything ever done before to produce cultivated meat at $10-20/kg.

One facility is estimated to require about one third of the bioreactor volume capacity that currently occupies the entire biopharmaceutical industry (Fassler, 2021).  To achieve high cell concentrations, strategies to supplement additional oxygen, remove waste-products, and prevent mixer shear stress are needed.  Additionally, the cost of the nutrient media used to grow the cells is another important consideration.

Foetal bovine serum has traditionally been used as a nutrient source, but it is expensive and derived from animals.  Many start-ups are working on replacing serum and lowering media costs with cheaper, animal-component-free sources (e.g. plant protein hydrolysates).  Keeping the bioreactors free from contamination also needs to be considered and will likely require usage of costly clean rooms.

Final Thoughts

The meat industry is a $1.7 trillion market with the global demand expected to increase with our growing population (Byrne et al. 2020).  The cultivated meat industry has an opportunity to capitalise on this massive demand, even 1% would lend huge pay-outs.  While the industry is still novel with many uncertainties ahead, there is much potential.

Collaborative partnerships will be critical for commercial success; start-ups partnering with existing food, ingredient, pharmaceutical and biotech companies.  Some start-ups have made much progress with some raising enough capital to build pilot-scale facilities to produce the first MVPs poised to enter the food market.  While the future of cultivated meat seems imminent, the scale-up challenges posed by critics cannot be overlooked and require serious consideration.  As cultivated meat products enter the marketplace, it’ll be up to consumers to decide its fate.

Acknowledgements from the author:

Special thanks to Daniel Noble, Hans Huttinga, Marleen Wintels, and Alison Rabschnuk  for their valuable input and feedback.

These unique properties of fibre can improve the sensory properties of many types of foods and beverages.  This can include texture improvements such as providing a firmer bite to a burger, enhancing the product’s processability such as increasing the cooking yield, and improving the nutritional quality due to the inherent nutritional properties.

In many meat and plant-based meat alternative products, other functional ingredients to fibres cannot be neglected or completely replaced.  However, thorough understanding of the functionality of fibres within application allows the improvement of characteristics such as texture, cooking yield, fat reduction, while also adding the health benefit of fibre enrichment to meat and plant-based meat alternative products.  This article will look at these aspects in more detail, focusing mainly on the functional role of fibre in meat and plant-based meat alternatives.

Functional Properties of fibre

Besides their nutritional benefit, dietary fibres provide a range of technological properties when incorporated in food systems.  Some of these are shown in the list below:

• • Water binding – The ability to bind water and swell.
  • Oil binding – The ability to bind oil and swell.
  • Anti-caking – The ability to prevent lump formation in powder materials.
  • Texturizing – The ability to enhance texture properties of food products (e.g. by providing viscosity, thickness, etc.).
  • Bulking agent – The ability to increase the volume in food products and thus increase the sense of satiety, especially in foods designed for weight reduction.
  • Fat mimetic – The ability to mimic (not replace) some of the organoleptic and physical properties of fat molecules while simultaneously providing lower energy values to the food products.
  • Gelling – The ability to thicken and form a gel. This depends on the product’s hydration properties and its ability to form a network

These unique technological properties result in fibres being used across a wide range of food products, from baked goods and confectionary, to dairy and beverages.  And although someone might not think about it at first, fibres are also widely used in meat and plant-based meat alternative products.

Fibre functionality in meat and plant-based meat alternatives

When it comes to meat and plant-based meat alternatives, fibre incorporation can deliver important functional properties while also also improving the nutrition of a product.

One key consideration when using fibres in meat and meat alternative applications is understanding how fibres behave in a complex matrix (proteins, starches, fat, salts, etc.).  As already mentioned, fibre has many unique functional properties, and each property can differ based on various parameters, such as:

• • Fibre source
  • Fibre extraction method
  • Chemical structure, pH, ionic strength
  • Fibre type: Soluble / Insoluble
  • Length of fibre
  • Fibre purity

Adding fibre to foods – how does this impact the product?

Depending on the fibre source (e.g. root vegetables, fruit peels, etc.) and extraction method (e.g. chemical vs microbial methods), different types of fibres can be obtained ¹.

The most common classification divides fibres into soluble and insoluble, based on their solubility in water.  Insoluble fibres consist mostly of cellulose, hemicellulose and lignin, and soluble fibres consist mostly of pentosanes, pectins, gums, and mucilage^2,3.

Insoluble fibres like bamboo or wheat have good water and oil holding capacity which will help in firming up the texture of cooked products. Water and oil binding properties are related to chemical structure, ionic strength, pH and particle size of fiber ⁴.  This feature can be helpful in the development of meat and plant-based burgers or sausages where we want to achieve a firmer structure by binding the extra water in the system. Depending on the extraction process, some fibres might still contain higher levels of starch that can gel upon heating and further enhance texture properties.

Another example is Psyllium, a soluble fibre that dissolves in water and can help with increasing viscosity of liquid systems such as brines. When going through a heat treatment process, psyllium also forms a gel-like structure that cannot be achieved with the use of insoluble fibres such as bamboo, wheat, or oat fibre.

The impact of water quantity on fibre functionality

Incorporating fibre in a food product can result in a higher or lower water (and/or oil) uptake.  As with many other ingredients, fibre will “compete” for the water in the system and this can also influence the functionality of some other ingredients, for example proteins and hydrocolloids.  One challenge in using fibres in plant-based meat alternatives is that very high concentrations of fibres can bind high amounts of water, making it less accessible to other ingredients.

If fibres are used in excess without enough hydration, the network formation between starches, proteins, and hydrocolloids can be disrupted, resulting in a very dry and perhaps too firm product.  Using fibres at very high quantities can also bring an additional and sometimes undesirable taste impact.  Flavour can be a challenge with plant-based products in general, as discussed in Flavour Masking Challenges in Plant-Based Meat Alternatives – Kerry Health And Nutrition Institute.

Benefits of adding fibre to meat and plant-based meat alternatives

As we have already briefly discussed above, fibre incorporation in meat and plant-based burgers and sausages can bring some application challenges.  However, a thorough understanding of different types of fibre and their functionality in application can result in very positive outcomes, such as:

• • • Increasing the yields of cooked minced products like burgers and sausages
    • Giving burgers a firmer bite with a more cohesive structure
    • Fat reducing properties while also keeping burgers and sausages juicy
    • Binding and upholding the water in fresh or cooked minced products

This article will look at how extracts are made, the requirements for flavourings in organic food products, and the various factors to consider when using these flavourings in application.

What are natural flavourings? What flavourings will be suitable for organic products?

The new organic regulation (Regulation (EU) 2018/848) offers 2 options regarding the use of flavourings in organic foods:

1a. Organic Suitable Flavourings

1b. Organic Certified Flavourings

2. Extracts (organic certified or not)

‘Natural Flavourings’ will no longer broadly be permitted in organic products, With the new Organic Regulation, only flavourings which are labelled as “Natural <X> Flavouring” (e.g. Natural Lime Flavouring) are permitted to be used in organic products. Within a natural ‘X’ flavouring, a minimum of 95% of the flavouring component in the flavouring must be sourced from the ingredient named in the flavouring, and the flavour source of the material must be easily recognised.  For example, with a natural lime flavouring, a minimum of 95% of the flavouring component must be derived from lime and the flavour perception of lime needs to be easily recognised. These flavours are known to be 95/5 flavours.

Since extracts are considered suitable for organic products under the new Organic Regulation, let’s review what an extract is.

What is an extract?

An extract is obtained from a material using a solvent by means defined by the Directive 2009/32/CE or by the less common more traditional press processes.

There are four main methods used to extract flavourings from source material:

Tincture: Raw materials such as leaves, roots, seeds, and flowers are combined with a blend of ethanol and water at room temperature.  The solids and liquids are separated, and the remaining liquid is a tincture.

Infusion: Like the tincture process, but instead the raw materials are combined with a blend of ethanol and water under heat. After heating, the solids and liquids are separated, and the remaining liquid is an infusion.

Distillates: Raw materials are combined with a blend of ethanol and water at room temperature and through a distillation process the liquid is fractionated. This liquid is known as the distillate.

Extracts: Raw materials are often combined with a blend of ethanol and water under heat. After heating, the solids and liquids are separated.  The solids or “crude” is concentrated and the liquid is re-used for another run. This liquid is the extract. In application (i.e. in a food or beverage) it is usually supported by a carrier such as glycerine or propylene glycol.

What flavouring source is best for different products?

There are many factors to consider when choosing the flavouring source for your product, such as:

• The raw material source, for example seeds and roots are less fragile than flowers or fruits and can therefore withstand harsher extraction processes.
• The final product and the process to make it. Such as a final product that undergoes a heat treatment step during the production.
• Cultural requirements, for instance halal products do not use ethanol as a solvent.
• The type of flavour profile desired. For example, a fresh top note versus a caramel, cooked lasting flavour.

Different methods of processing raw materials produce different types of flavour extracts. These types of extracts are processed differently but can still produce 95/5 flavours appropriate for organic products.

As mentioned earlier, according to the legislation the flavouring source must be easily recognised (e.g. lime flavouring should taste like lime). This is critical to get correct, therefore it is important to consult a flavourist team supported by sensory analysis.

Some natural flavouring sources are more delicate than others or contain less volatiles. In some cases, they are very difficult to extract or can become partially destroyed during the extraction process. Extracts in general can have less intense flavour at low application levels. All of these conditions can result in a need for high application levels.

How can the intensity of extracts be improved?

From around 3000 years BC, method and extraction processes are improving to target the best extract. But what is regarded as the best extract? It is an extract with a lot of top notes. It is fresh and authentic. A high-quality extract can make you feel like you’re tasting the real thing, like biting into a wild strawberry foraged in a forest.

However, every extraction process gives a different result in terms of taste, volatiles, and intensity. For example, water will extract more sugars than alcohol, but alcohol will be more efficient to capture organic volatiles. Therefore, usually a blend of solvents in different ratios are applied to create the desired balance. The intensity of an extract usually depends on the concentration of the flavouring source in the final product quantity. For example, black tea extracts can range in intensity from 1 to 800 times.

An experienced analytical team is crucial to support the development of extracts and flavourings. They investigate each stage of the process and analyse the quality of the final extract. This ensures the correct level of concentration is selected for the application. For instance, vanilla extracts must contain a minimum % of vanillin to be legally defined as a vanilla extract, and authorities use analytical methods to identify adulteration of this premium product. The type of analysis required to determine this is also specific, and conventional analytical techniques such as gas chromatography are unable to discriminate between synthetic and natural molecules, therefore isotopic analysis is required using a mass spectrometer.

Choosing the right natural ‘x’ flavouring

This requires a team effort. A combination of experienced flavourists, efficient extraction processes, analytical scientists, and an application technologist that is knowledgeable on the specific food process and its interaction with the flavourings are all key to produce a great tasting product.

Emulsifiers in Food – What Do They Do?

Emulsifiers in food are used to improve quality or shelf life through strengthening dough in baked goods, stabilizing foams, preventing food from getting stale, or making foods more freeze-thaw stable. They can be derived from a range of products like soy and sunflower lecithin to propylene glycol alginate. Emulsifiers can bind to two liquids that usually do not mix well together. A traditional example is mixing (or rather, trying to mix) oil and water. These fluids don’t like to mix because of their chemical properties. This is where an emulsifier comes into play. Emulsifiers have water loving (hydrophilic) and oil loving (hydrophobic) regions that allow the two immiscible ingredients like water and oil to join. For example, if you pick up ranch dressing, you don’t see oil bubbles dispersed throughout the product. The emulsifiers in the product keep all of the liquids mixed smoothly.

In the continuing age of decreasing the amount of food additives, it is important to understand why some of them are utilized so heavily in the food industry. Emulsifiers and their function in food allow the consumer to view their food in a consistent, smooth and quality manner. Prior to the addition of an emulsifier like mono- and diglycerides in your peanut butter, you would have had to continuously mix the oil and solid phase together to prevent separation. Food manufacturers add these ingredients to ensure a standard product across the board and to make it more convenient for consumers to use, ultimately saving time.

What Foods Contain Emulsifiers?

Emulsifiers in Baked Goods

Cake, yeast raised goods like donuts, icing, filling, bread and specialty cakes all utilize emulsifiers. When these baked goods lack emulsifiers they show quality defects and negative sensory remarks including; tough, dry, stale or tasteless (Brandt 1996). On top of the negative sensory attributes associated with baked goods, without emulsifiers, shelf life is also reduced.

So what do emulsifiers do in these delicious treats?

The answer is the same things eggs do when you add them to baked recipes, since the lecithin in egg yolks acts as an emulsifier. Emulsifiers help the shortening ingredient in the dough of baked goods perform better. Emulsifiers do this by improving tenderness, flavor release, volume, water absorption, texture, and reduces the use of egg, shortening and mixing time (Orthoefer 2008). Emulsifiers in baked goods not only increases positive sensory attributes in terms of flavor and texture, but also lend a hand in the sustainable movement. Keeping baked goods fresher longer and reducing the amount of food waste. So when you see ‘soy lecithin’ on an ingredient panel, know that it is just a different source of the same ingredient (lecithin) found in egg yolks.

Emulsifiers in Dairy Products

To influence the stability and texture of your favorite dairy products including ice cream and processed cheese, the use of an emulsifier is necessary. In ice cream, emulsifiers are used because the ice cream whips easier, does not melt as fast on a hot sunny day, has a smoother body and texture and the air particles within the ice cream are more uniformly spread across (Euston 2008). In processed cheese, the final water content can go up to 58% water and around 15-25% fat (Euston 2008). The large portion of immiscible liquids within this product make it nearly impossible for this product to be made in a uniform and consistent manner without the use of emulsifiers, specifically emulsifying salts.

Emulsifiers in Infant Nutritional Foods

When it comes to emulsifiers found in children’s infant formula there are two types, one protein based and another non-protein based (McSweeney SL 2008). Various by-products of bovine milk including skim milk powder, milk protein isolate, whey protein concentrate and more are considered the protein based emulsifiers. These emulsifiers work well due to their amphipathic (water and oil loving regions). The non-protein based emulsifiers including lecithin, mono and diglycerides, citric acid esters of mono- and diglycerides of fatty acids and more are the main emulsifiers in infant nutritional foods (McSweeney SL 2008). Both types of emulsifiers are utilized to improve the stability of the product and to help form a stable emulsion. The addition of these ingredients will help prevent defects including:

• • Oiling off – Oil appearing on the surface of the infant product
  • Creaming – Upward movement of droplets caused by gravitational force
  • Sedimentation – Downward movement of droplets from having a higher density than the surrounding liquid
  • Ringing – A white ring at the top of a container and
  • Water and oil separation (McClements 2016).

Although these defects are a concern of quality and not of safety, observing these defects in your children’s formula on a consistent basis could cause the consumer to think twice about purchasing these infant nutritional products. Emulsifiers are there to ensure defects like the ones above do not occur and to make sure every ingredient is suspended in the food matrix uniformly.  Emulsifiers are there to improve and maintain the way consumers view their food while extending the shelf life of various food products.

What Are Examples of Emulsifiers in food?

Emulsifiers in food

Emulsifiers and surfactants used within the food industry to aid in maintaining attributes associated with each food product and to decrease unfavorable sensory characteristics within each food matrix. (Reproduced from Hasenhuettl 2008)

The table above shows examples of common emulsifiers, where they are found, and what they do in that food or beverage. Consumers are constantly on the lookout for more natural emulsifiers due to negative press some emulsifiers, like polysorbate 80, have received over the years. Some fibers, like gums, are able to be used as emulsifiers while also providing fiber content and prebiotic benefits for gut health. These may provide a solution as consumers seek to avoid more synthetically based emulsifiers.