Fibre is part of our daily food intake and it is a substance our body cannot fully digest; it passes along our digestive system and helps prevent constipation. Even though it is a carbohydrate, fibre cannot be broken down into sugar molecules like other typical carbohydrates due to its structure. Fibre also comes in two forms—soluble and insoluble—and these help regulate the body’s use of sugars, keeping hunger and blood sugar in check.
The global dietary fibre market is predicted to grow at a compound annual growth rate of 13.2 percent and reach US$4.31 billion by 2020, according to market intelligence company, MarketsandMarkets.
Consumers are increasingly aware of the health benefits of fibre and are looking to add more fibre to their diets. Fibres have numerous health benefits that can help meet demand for nutrition in foods and this represents a major opportunity for food and beverage manufacturers to respond by producing fibrefortified foods and beverages.
Food And Fibre
Whole foods are rich in dietary fibre and can be found in plant foods that are unprocessed and unrefined, or minimally processed and refined, before being consumed. Examples of whole foods include whole grains, tubers, legumes, fruits and vegetables.
Whole foods are also beneficial to health in other ways as they contain a wide variety of nutrients in a single food—which includes vitamins, minerals, phytonutrients and essential fatty acids. Fibre food supplements can also be added to foods and liquids to boost fibre content. Used in such applications would be purified fibres also termed ‘functional fibres’—such as wheat dextrins, inulin and cellulose.
Types Of Fibre
There are two types of fibre: insoluble and soluble. Insoluble fibres cannot be digested by our bodies and they do not dissolve in water. They are naturally found in the outer bran layers of wholegrains—such as wholemeal flour, wholemeal bread, brown rice and wholegrain pasta. This type of fibre adds ‘bulk’ to waste products, and prevents constipation.
Foods with insoluble fibres include brans and insoluble fractions (e.g. soybean, sugar beet, oat, corn, cellulose, bamboo, fruits), and resistant starches (e.g. corn, tapioca and potato). Resistant starches are derived from varying botanical sources and they resist digestion and pass through to the large intestine. They also have low caloric contribution. The functional benefits of resistant starches include a smooth mouthfeel, good gut tolerance, and their ease of use for fibre fortification in foods.
Soluble fibres cannot be fully digested by our bodies too but can be used by our bowel bacteria as their food source. They dissolve in water, and can help lower glucose levels as well as blood cholesterol as they bind to substances like cholesterol and sugar, preventing or slowing their absorption into the blood. They can also offset hunger by making people feel full for longer, which can help with weight management.
Foods rich in soluble fibre include oats, nuts, beans, fruits such as apples, avocados and blueberries, and vegetables. It is also possible for soluble fibres to be added as tasteless powders to drinks to boost fibre intake, and for the fibre to be ingested as a dietary supplement to meet the daily requirement for it.
Why Is Fibre Important?
A low-fibre diet is associated with many health problems, including cardiovascular diseases and high blood fats, gastrointestinal disorders, cancers, poor bowel function, and diabetes, as fibre influences blood sugar, insulin, body fat and high blood pressure levels.
New research has also found that fibre’s benefits extend beyond preventing only these diseases; it can also lower the risk for knee osteoarthritis. A fibre-rich diet could also shape the immune system to reduce allergies to substances such as peanuts, and soluble fibre supplements could become a complementary treatment for people with poorly managed asthma.
Functions Of Dietary Fibre
Dietary fibres have three primary functions: bulking, viscosity and fermentation. Different fibres can influence the body differently, and including a variety of dietary fibres in the diet can therefore contribute to overall health.
Bulking fibres can be soluble (such as psyllium) or insoluble (such as cellulose and hemicellulose). They absorb water and can significantly increase stool weight and regularity.
Viscous fibres thicken the contents of the intestinal tract and may reduce the absorption of sugar, lessen sugar response after eating, and reduce lipid absorption. Its use in food formulations is often limited to low levels, due to its effects on viscosity and thickening.
Fermentable fibres are consumed by the microbiota within the large intestines, mildly increasing faecal bulk and producing short-chain fatty acids as by-products. Resistant starch, inulin, fructooligosaccharide and galactooligosaccharide are dietary fibres which are fully fermented.
Tasty And Healthy Fibre-Fortified Options
Consumers around the world are not getting enough fibre in their diets, and this represents a huge market potential for food and beverage manufacturers to respond by providing fibre-fortified products that are also tasty. Consumers are increasingly aware of the health benefits of fibre, and want to add more fibre to their diets. Products that offer digestive health benefits, have fewer calories from sugar, and have cleaner labels would appeal to consumers looking for healthier options. Fibre fortification can help manufacturers meet all of these changing consumer needs.
High-fibre diets are growing in popularity as compared to low-fat or low-calorie diets, and consumers want products that make them feel good about what they are consuming. Integrating healthy nutrition within their regular daily routines via small changes will help them start on their journey towards health and wellness without them needing to make drastic changes to their lifestyles. Prebiotics can be incorporated in beverages without changing the taste and texture, and it is one of the ways to create new fibre-fortified solutions to meet today’s consumer needs.
Choosing The Right Fibre
Food manufacturers should consider the right type of fibre for their specific food, drink or supplement application. In addition to their inherent benefits, fibres can also provide the functionality needed to meet the demands for providing bulk or even a good mouthfeel in reduced-sugar products, for example.
Fibre source should also be considered as total dietary fibre content varies among the different sources—e.g. oats has 96 percent in fibre content, inulin has 93 percent and chia has 34 percent. The type of fibre should also be considered for its water holding capacity (which will affect the shelflife and re-formulation issues), its level of solubility, if it is allergen-free, and its sensory characteristics, i.e. mouthfeel, flavour and colour.
There are a variety of fibres to choose from: resistant starch, inulin, polydextrose, fructo-oligosaccharides, acacia gum (gum Arabic), hydrolysed guar gum, and isomaltooligosaccharide. The ratio of insoluble to soluble fibres should be 75:25, which makes a diet naturally balanced and as nature intended as this is the ratio fibre is found in natural foods.
Fibre can also be added to supplements or used as food additives. Soluble fibre supplements may be beneficial for alleviating symptoms of irritable bowel syndrome, such as diarrhoea, constipation or abdominal discomfort. Prebiotic soluble fibre products—such as those containing inulin or oligosaccharides—may contribute to relief from inflammatory bowel diseases such as Crohn’s disease and ulcerative colitis. This is due to the short-chain fatty acids produced with subsequent anti-inflammatory actions upon the bowel.
An insoluble fibre, such as a resistant starch from high-amylose corn, can be used as a dietary supplement and it could contribute to improving insulin sensitivity and glycaemic management, as well as promoting regularity and relief of diarrhoea.
Huge Market Potential In Fibre
Data from Euromonitor showed the digestive health market was worth US$70 billion globally in 2015. The trend towards health and wellness sees consumers moving towards eating more functional foods. As different fibres can provide a wide array of benefits, manufacturers should choose the right type of fibres to add to their products, so as to deliver the desired health benefits and meet consumer expectations on taste.
From a manufacturer’s perspective, the right fibre should have no taste or colour impact on the end product, and should offer a good mouthfeel and consistency.