Acacia fibre (also called gum acacia or gum arabic) is a novel source of soluble dietary fibre.

In recent years, the popularity of Acacia fibre as a food ingredient has grown strongly at 27% CAGR (2016-2020), with Western Europe accounting for greater than 50% of new product launches (Innova Ingredient Sizing, 2022) due to its health benefits and functionality in foods and beverages.

What is Acacia Fibre?

Acacia fibre (gum arabic/gum acacia) is a form of soluble dietary fibre produced using the natural exudate from the Acacia tree in the Sahel Region in Africa.

It is harvested in a very similar way to another exudate you may be more familiar with: maple syrup from the Maple tree.  Acacia’s use in food dates as far back as the 9^th century, where it expanded its global footprint through trading on ancient spice routes.

Fibre is Under-Consumed in the US and Europe

Fibre is linked to a wide range of health benefits, but many parts of the world consume fibre-deficient diets.

Reformulating with fibre presents an exciting opportunity for food and beverage manufacturers to innovate through fibre fortification while simultaneously reducing the calorie content of food by enabling sugar or fat reduction.

Fibre is mainly found in foods like fruits, vegetables, and legumes, which many people do not consume enough of.  There is an opportunity for the food and beverage industry to improve public health by adding fibre to foods and beverages people are already consuming.

Fibre Statistics

Although people are under consuming fibre, consumers are catching on to the health benefits of fibre and are looking to get it more easily in the foods they are already consuming.

• • More than 60% believe that eating more fibre is the best way to manage digestive health (Kerry Global Consumer Survey – Digestive and Immune Health, 2019).
  • Fibre is the most widely used positioning related to digestive health (Innova 2021).
  • 68% of global consumers are influenced by sustainability when purchasing F&B products in store (Kerry Consumer Research, Sustainability in Motion, 2021), 42% of consumers agree that ‘a product is not healthy if it is not also sustainable’ (Innova, 2021).

Choosing a Fibre can be Challenging

These figures show that there is great opportunity to fill a public health need and consumer demand at the same time.

This important public health challenge is being taken up by food and drink manufacturers through such programs as the UK Food and Drink Federation’s recently launched initiative dubbed “Action on Fibre”, with organisations proactively pledging to bridge the fibre gap across bakery, beverage, cereal and snacks categories.

However, fibre addition is not always straightforward. It can be hard to find a source of fibre that is easy to add to foods and beverages.  For example, some fibres cause beverages to thicken or become more viscous, which can be undesirable.

Different fibres also interact in different ways with the human body, which means fibre sources vary in their health benefits and side effects when consumed.  It can be challenging to choose a fibre source, but acacia fibre is one source that can deliver health benefits while making formulation easier in certain applications.

Why is Acacia Fibre Gaining Ground?

Studies on Acacia show prebiotic effects and a role in digestive health

Clinical studies have shown Acacia fibre promotes the growth of healthy bacteria in the human digestive system.

In a clinical trial, doses of 10 grams of acacia fibre per day led to a significant increase in Bifidobacterial and Lactobacilli, and the prebiotic effect was more effective than the same dose of inulin.

A similar prebiotic effect was shown in another study by Cherbut et al., which was also linked to a greater stool weight, indicating a potential links to positive digestive health benefits.

Acacia fibre has been linked to improvements in satiety and cardiometabolic health in studies

Acacia fibre may also play a role in weight management.

In clinical studies, Acacia fibre has bene shown to significantly improve satiety at 5g/serving and subsequently significantly reduced the energy intake at first meal three hours after ingestion and the feeling of hunger for at least three hours after consumption with no compensation effect.

When incorporated into foods and beverages, acacia fibre was linked to decreased hunger and improved fullness.  Acacia fibre intake has also been linked to cardiometabolic health such as significantly improving fasting glucose levels, expanding potential uses for Acacia fibre beyond digestive health.

Acacia fibre does not cause as much GI discomfort as other prebiotic fibres

A major complaint with many consumers is that, despite a role in health, some fibres can cause negative side effects like excess gas production and bloating even when consumed at amounts as small as 5-10 grams per day.

This has led many to seek alternative fibres that are linked to health benefits but do not cause GI discomfort.

In studies using acacia fibre, doses up to 40 grams per day were well-tolerated with no significant increase in discomfort and led to fewer reported side effects than FOS, demonstrating excellent digestive tolerance for acacia fibre.

*Check with local regulatory bodies for country specific claims

Global regulatory bodies recognise the health benefits of Acacia as a fibre source.  The application of Acacia fibre can deliver a high concentration of soluble dietary fibre (minimum 85%) that enables a “High in Fibre” claim (6g of fibre per 100g of product in Europe).

Last year, the U.S. Food and Drug Administration announced that it intends to propose that “Acacia (Gum Arabic)” also known as gum acacia, be included as part of the FDA’s definition of dietary fibre further propelling Acacia fibre as a key solution to increase the uptake of dietary fibre.

The FDA has determined that the scientific evidence supports that gum acacia can help reduce blood glucose and insulin levels after it is eaten with a meal containing a carbohydrate that raises blood glucose levels.

Acacia Fibre is Sustainable

• • It has a role in sustainable agriculture.  The Acacia tree helps helps combat desertification and increase other crops yields in the Sahel region in Africa.
  • Farming of Acacia supports local communities. the harvesting of Acacia fibre is carried out by local farmers in a way that does not damage tree growth and forms an important source of secondary revenue, making it a critical income generator among vulnerable communities – up to 38% of total annual income.

Acacia’s Functional Role Beyond Contributing Fibre

Acacia fibre is non-cariogenic with minimum impact on the taste, aroma, texture and visual properties of food and beverage products.

This makes it highly versatile across numerous applications such as bread, beverages, nutritional bars and cereals for manufacturers wishing to achieve a fibre claim and/or improve the nutri-score of their final product.

White bread:  Although white bread is the most popular type of bread globally, its low fibre content gives it a poor mark on the nutrition scale.

Acacia fibre–fortified white bread can provide up to a 300% increase in fibre per serving versus non-fortified white bread, a level that approximates the fibre content of whole wheat—all whilst maintaining the taste and consistency that leads so many consumers to purchase white bread products.

Through application testing, sensory and texture analysis results confirm taste and aroma are unaffected negatively when Acacia fibre is incorporated.

The same is true of measurements of loaf volume, softness, crumb and crust colour and there is little impact on dough rheology, making it easy for bakers to handle.

Further application trials carried out demonstrated that other fibres on the market such as citrus fibre, soluble corn fibre, and inulin can negatively impact the sensory and dough handling properties of bread.  For example, inulin resulted in the bread being much more dense, lower volume, firmer and with an undesirable texture.

Favourably, Acacia fibre fortified bread remains comparable to reference “control” bread, making it a great candidate when choosing a suitable fibre for fortified baked goods.

Beverages: In beverages there are important practical considerations to take into account when fortifying with fibre.  The fibre ingredient needs to be easily dispersible, highly stable in low pH and void of negative influences such as gelling, swelling or thickening.

Acacia fibre meets these criteria with added benefits of improving mouthfeel and flavour enhancements.

It has a role in reduced-sugar beverages due to the ability of the polysaccharide structure to improve the mouth coating effect, which holds sweeteners or flavour modulators in the mouth for a longer period of time and extending the sweetness perception.

It has the ability to reduce the GI of food products and is Low-FODMAP and KETO diet suitable.  The high fibre, increased satiety attributes of acacia fibre are particularly suitable for beverages in categories such as sports nutrition and those positioned as meal replacements.

Nutritional Bars and Cereals: Nutritional bars and cereals frequently fall into the high fat/sugar/salt category.  Manufacturers looking to optimise their nutri-score and fortify with fibre should consider acacia fibre to improve the nutritional positioning of their product.

Along with delivering a high concentration of soluble dietary fibre, acacia fibre supports the overall reduction of sugar in final application by working as a binder to partially replace sugar syrups.

It also maintains moisture balance preventing dry mouthfeel over shelf-life, which is a common challenge of nutritional bars and cereals/ granola.  This binding function is different than that provided by soluble fibres like inulin or FOS, which can act as bulking agents and provide sweetness but do not aid in binding.

As a result, including Acacia fibre as part of a blend of fibres may enhance functionality of the entire system.

Dietary fibre has become an important functional ingredient in recent times due to growing consumer interest in the many health benefits of fibre touted by the scientific community (Anderson 2009).

Fibre has been recently defined by the FDA as “non-digestible soluble and insoluble carbohydrates (with three or more monomeric units) and lignin that are intrinsic and intact in plants; isolated or synthetic non-digestible carbohydrates (with three or more monomeric units) determined by the FDA to have physiological effects that are beneficial to human health.”

Here, the monomeric units refer to individual sugar molecules.  Current food trends point strongly to dietary fibre due to its versatility as a food ingredient, connection with weight management and digestive wellness, and association with the concept of natural.

Fibres play an important role in gastrointestinal health, with new scientific findings into the effect the fibre on bowel movements, cardiovascular health, blood glucose metabolism, and the microbiome constantly adding to the growing evidence that fibre is a critical component to a healthy diet (Vuksan 2008, Pereira 2004, Giacco 2000, Maslowski 2011).

Sources of Fibres

Dietary fibres are typically derived from the indigestible parts of plant materials and made up of long repeating chains of sugars.  The most common fibres are from the exterior husk of cereals and grains, which contain the insoluble fibres cellulose and lignin.

Both cellulose and lignin are main components of most plants and can be found in the tough, fibrous materials of plant-based products. Plants use these fibres to protect themselves. Wood is an example of a material made from cellulose and lignin, but these fibres are also a main part of the skin of fruits and vegetables.

The edible interior of the seeds contains mostly digestible starch, with some fraction of resistant starch.  These resistant starches are in a form that cannot be broken down by the starch-degrading enzymes released by the human intestines due to either being enclosed by other indigestible fibres or existing in a high-density crystalline form.

Unlike digestible starch, crystalline starch has no gaps for the enzymes to effectively bind.  Beans also have similar fibre components as well as a large portion of raffinose, a simple three-sugar carbohydrate.

Some beans produce specialty fibre materials which are used as thickening agents in product formulation, such as locust bean gum and guar gum.

These gums are commonly used in gluten-free doughs for improve viscosity, as well as ice cream to enhance texture quality.

Fruits are an important source of lignin, as well as pectin, which is used as a gelling agent to produce jams, jellies, and marmalades.

Marine products are also a rich source of fibre ingredients.  Carrageenan, agar, and alginic acid are all soluble fibres with gelling properties traditionally extracted from sea algae.

Chitin and chitosan are non-plant fibres both sourced from the hard shells of marine crustaceans such as crabs, lobsters, and shrimp.

Inulin, another important fibre used in the industry, is found abundantly in chicory root or Jerusalem artichoke.  Xanthan gum, a thickening agent and stabilizer, is produced from simple sugars using a specific strain of bacteria.

Some dietary fibres are produced synthetically by chemically modifying starches to form another subclass of resistant starches.  These synthetic resistant starches are either chemically linked together across sugar chains or modified at each individual sugar unit to generate food ingredients that cannot be readily broken down by human digestive enzymes.

Other fibres can be chemically or enzymatically modified to change their functional properties as food ingredients.  For example, pectins can be reacted with either ammonia or hydrochloric acid to create semi-soluble fibres that gel at lower sugar concentrations than the parent molecule.

Dietary Fibre for Health

Dietary fibre is a nutrient most people know is beneficial but few people get enough of. Despite research consistently showing a variety of health benefits associated with fiber, less than 10% of people in the US meet dietary recommendations.

When it comes to health, fibres can have many different definitions. They can be categorized as water insoluble, water soluble, viscous, non-viscous, fermentable or prebiotic, to name a few.

The number of different categories speaks to the complexity of these ingredients. Each of these types of fibres can have different behaviours and benefits in our bodies, and the scientific community continues to reveal what these benefits are.

Here are some examples.

• Insoluble fibres, which do not dissolve in water, can serve as bulking agents for stool and contribute to regularity. These are the main fibres associated with digestive health. They are most often found in fruit and vegetable skins, whole wheat, seeds and nuts.
• Soluble fibres dissolve in water and are most known for their association with satiety, heart health, and blood sugar regulation. Studies have shown some soluble fibres can slow the rate food moves through our digestive tract, which can reduce the speed we absorb sugar and also make us feel full for longer. Fibres like beta glucan (mainly found in oats) have been shown to reduce LDL cholesterol, potentially reducing risk of heart disease. Oats, beans, flax seed, and some fruits and vegetables, such as apples, contain soluble fibre.
• Some fibres are also categorized as prebiotic, which means they provide beneficial bacteria in our colon with a source of energy. When these bacteria digest prebiotic fibres, they create metabolites like short chain fatty acids which can have a variety of beneficial effects. Inulin is a widely used prebiotic fibre. For more information on how prebiotic fibres work, read ‘Fiber and Prebiotics: Mechanisms and Health Benefits’ by Dr. Joanne Slavin.

Fibre as a Food Additive

While the health benefits of consuming dietary fibre are clear, consumer perceptions of fibre are still influenced by the sensory characteristics imparted by these ingredients.  In particular, formulators are challenged to include fibre in food products while maintaining consumer acceptability for taste, texture, colour, and aroma.

Several challenges exist for product developers interested in incorporating more dietary fibres into food products.  The physical and chemical behaviour of fibres create a natural constraint for the amount of fibre that can be added to any one product.

For example, acidic foods can cause some fibres to break down into simple sugars over time, which may result in a product that falls short of the regulatory requirements needed for health claims.  Pectins, alginic acids, carrageenans, and guar gum all readily gel in the presence of calcium, which can pose problems when formulating with dairy or other high calcium products.

The taste and texture of a food product are also affected by fibre concentration, as many insoluble fibres can produce a gritty sensation when eaten.  Some prebiotic fibres may cause bloating and discomfort due to the gas produced as a by-product of bacterial digestion.

Fibre and the Future

Designer fibres are increasingly becoming important functional ingredients for incorporating more fibre into food products while maintaining desirable healthful and sensory properties.  Chitosan-coated konjac glucomannan is a hybrid fibre ingredient used to improve the viscosity of foods used for weight reduction (Woodgate 2003).

Resistant glucan and hydrogenated resistant glucan are newly developed soluble fibres composed of glucose that are being studied for their potential role in reducing incidence of metabolic syndrome, the cluster of conditions that contribute to lifestyle diseases (Nakamura 2016).

Several novel processes are currently in development to produce novel resistant starches.

Continued innovation in the dietary fibre space will require an understanding of consumer demand for functional food products balanced with the desire for great taste.