Strengthening Products with Fiber

Fiber historically connotes strength and a certain roughness. It is positioned as the heart  of a person's worth. When someone has strong conviction to do good, they are said to have good moral fiber. Others may call it strong fiber of character. People standing up to President Dwight Eisenhower once touted the spiritual fiber of a nation (as being more than its wealth). When someone gives a task all they've got or stands up for his beliefs, he is said to do so with 'every fiber of his being.'

Dietary fiber is not unlike its metaphorical cousin. Often called "roughage," dietary fiber is the indigestible portion of a plant. It is ingested in foods or supplements, but it is not digested like other nutrients. However, like other nutrients, fiber can undergo changes in the digestive system, but instead of breaking down into nutrients that absorb into the bloodstream and other parts of the body, fiber passes through tot he large intestines and is affected only by water. Soluble fiber dissolves in water and ferments in bacteria colonies in the colon. This produces gases and short-chain fatty acid byproducts that are proving beneficial themselves. In addition, soluble fiber can bind to bile acids, preventing them from being absorbed, and can slow the emptying of the stomach, causing sugars to be absorbed more slowly. For its part, insoluble fiber does not dissolve in water, but absorbs water as it passes through the digestive tract. This adds bulk to the stool, which helps to keep the digestive process moving along and promotes healthy elimination.

On the surface, fiber seems married to digestive health, and that is what most consumers first know of the value of dietary fiber.  Cheryl Sturm, director of marketing for Embria Health Sciences, said mature brands such as Metamucil have helped to establish a strong link between fiber and digestive health. " The average consumer has little knowledge regarding types of fibers, but does know that 'fiber is good for me,'" she said. "Primary grocery shoppers and those consumers more invested in self-health may have a broader knowledge due to package claims associating oats and heart health as well as others making an association with immune health claims."

Teresa Yazbek, U.S. vice president and technical sales director for Nexira  noted the average consumers may know more about fiber, but they might not know exactly all the benefits; they do seem to know it is part of a healthier diet.

A new study from Tate and Lyle (conducted by third-party research firm Illuminas in 2011) revealed conflicting consumer awareness. While 90 percent of Americans see digestive health as a top health priority, only half think they need more fiber in their diets; the American Heart Association (AHA) recommends a fiber intake of 25g/d to 30g/d, but notes average intake among Americans is around 15 g/d. The survey also found more than half of consumers polled always or usually read ingredient labels, with three out of 10 consumers looking specifically for fiber content.

Cathy Arnold is a senior formulation scientist for Fortitech Inc., a premix supplier. From this perspective, dealing mostly with formulators, she spots clues to consumer trends in the requests Fortitech gets from clients, typically formulators. What she has found shows the increasing departure from the earlier digestion-only consumer mindset. "It seems that products addressing heart health through cholesterol management are clearly in demand and that the consumer mindset on fiber is heavily focused on this area due in great part to the awareness created by consumer media," she said. "While we have seen heart health as a key driver in terms of formulation requests, formulation for weight management products is also in high demand." However, Arnold questions how much the average consumer understands the role fiber plays in weight management. " It would be interesting to see how many people on the street, so to speak, understand the term satiety and what it means for this product category." Fortitech is also seeing an increase in formulation requests for products that address immunity by optimizing gut health.  "As more consumers understand and embrace the concept of the role that digestive health plays in overall health and wellness, the market for fiber-enhanced products will continue to grow."

Sturm said the benefits can vary by type of fiber; some are associated with digestive health, some with heart and immune health. "The average American diet, deficient in fruits and vegetables, opens doors for products that can conveniently deliver benefits in a cost-efficient manner without side effects," she said.

Types of Fiber

Insoluble fibers include cellulose, hemicelluloses and lignins; soluble fibers include pectin, gums, chitin and beta glucans. Each fiber type can be sourced from many different plants , but it is important to note plants offer some ratio of both soluble and insoluble fibers. For instance, psyllium is about 7:3 soluble:insoluble fiber, as is larch arabinogalactan.

Some soluble fibers are also considered prebiotic because they stimulate the proliferation of beneficial bacteria (probiotics) in the digestive tract. According to the International Scientific Association for Probiotics and Prebiotics (ISAPP), a prebiotic effect requires resistance to degradation by stomach acid, enzymes or hydrolysis; fermentation by intestinal microbes; and selective stimulation of the growth and/or activity of positive microorganism in the gut. The primary prebiotic fibers are fructooligosaccharides (FOS) and galactooligosaccharides (GOS). Inulin is a popular form of FOS, and some other emerging prebiotics include polydextrose, soybean oligosaccharides, isomaltooligosaccharides, gluco-oligosaccharides, xylo-oligosaccharides, palatinose, gentio-oligosaccharides and sugar alcohols (such as lactitol, sorbitol and maltitol).

Packaged Facts reported that in 2004, 91 percent of all U.S. sales of fiber were conventional insoluble fibers, with the remaining 9 percent divided between soluble fibers and novel fibers. However, the firm predicted a major shift in market share among the fiber types by 2014. Novel fibers showed the strongest growth between 2005 and 2009, posting a compound annual growth rate (CAGR) of nearly 66 percent, driven by polydextrose (about 55-percent CAGR). The data further showed chicory root/inulin  had a 42-percent CAGR  and FOS/fructan had about a 36-percent CAGR during the same period. They noted GOS, resistant starch and soluble corn fiber/resistant corn dextrin all saw doubled or tripled growth rates after being introduced to the market.

Larry Robinson, Ph.D., vice president scientific affairs for Embria Health Sciences, said the most common prebiotic fibers are polymers of the sugar fructosesuch as FOS and inulin. "FOS is generally defined as having no more than 10 sugars in the oligosaccharide, while inulin has at least some polymers that contain more than 10 sugars," he explained. " It is becoming more common now for some products to contain both probiotics (live beneficial bacteria) and prebiotics."

Arnold reported inulin and oligofructose (OF, another name for FOS) are popular in fiber-containing premixes. She pointed out these fibers are naturally occurring in several plants, fruits and vegetables such as artichokes, chicory, garlic, leek, onion, wheat, barley and banana, and they offer a range of functional and nutritional benefits. "As well as providing all of the traditional benefits of fiber, they also function as prebiotics, which means that they contribute to healthy gut flora," she confirmed. "They stimulate the growth and activity of Bifidobacteria in the colon, which helps to decrease the risk of many digestive illnesses, and at the same time, they help boost the bodys absorption of calcium in the colon, which increases bone mineral density."

She explained because inulin and OF/FOS are soluble fibers, they can be used in a variety of products including bars, beverages, cereals, baked goods, confections and dairy products.  "They can also reduce the amount of sugar, fat and overall calories in a product without a negative impact on taste and texture," she said. " With a flavor profile similar to sugar, they have  no aftertaste or off notes, and their flavor-masking ability is ideal for masking the bitter notes of many vitamins and minerals."

Yazbek noted the various fiber types fit well with certain product types. A baked product or a breakfast cereal would mainly use insoluble fibers,  while a beverage would tend to use more soluble fibers because of texture requirements for beverages and cost for baked goods or cereals.  "There are always exceptions; for example acacia gum, such as Fibregum, is used in baked goods as a fiber that improves texture, extend shelf life, etc.," she said. " In beverages, not only is a soluble fiber preferred, but it has to be a soluble fiber that is stable in an acidic medium (e.g. juices) so there is no loss of fiber content during the shelf life." On beverages, she further noted some fibers are avoided due to the high potential of causing side effects such as bloating and gas.  When it comes to supplements, she said consumers are more educated and know what they want, so they might choose to use a bulking fiber, such as psyllium,  as a laxative to help fight constipation or choose a soluble fiber (e.g. acacia fiber and/or inulin) as a supplement to improve their overall health.

Fiber Applications

Fiber has historically been tied to the bakery, cereal and bars category, but growth in the fiber market is in other areas.  "Now we are seeing formulations that include fiber being requested in products ranging from beverages, such as enhanced waters and juice, to products within the dairy category, such as yogurt and ice cream," Arnold reported. "Many of our formulations that include fiber are targeting weight management, cardiovascular health and immunity." She reasoned  consumers are increasingly taking the management of their personal health into their own hands and are recognizing the long-term benefit of cost savings, if they can avoid or delay the use of prescription drugs to address potential health issues.

According to Yazbek, the bakery segment will still grow, but so will beverages. "There is a general growth on fiber content products mainly because of health benefits," she said, adding demand for natural and even organic fibers is following the natural and clean label trend.  "We are expecting a growth of fiber-containing products in Canada because Health Canada recently has approved Fibregum, our brand of acacia gum, as a natural source of fiber."

Fiber has done a 180-degree turn from the past where it was, according to Sturm, who said Fiber was one of those subjects that didnt come up in polite conversation, but is now a real part of a healthy diet. "New ingredients, such as chia, are garnering attention and opening up doors for including fiber in beverages and other products where there may previously have been organoleptic issues," she noted. "There continues to be growth in adding fiber to baked goods of all kinds in the food sector, as well as new prebiotic/probiotic combinations in the supplement aisle."

Organoleptic issues are just one challenge in formulating with fiber. With so much growth in fiber ingredient types and applications, each project is bound to have a specific set of challengesas Arnold said, "There is no one-size-fits-all approach to [fiber] formulation."

Yazbek suggested food and beverages pose more challenges than supplements. "When buying a health food (with fiber), consumers still want to enjoy it, so the first challenge would be to make the fiber rich food/beverage to taste as good as a product with no fiber," she said. Another concern is potential for over-consumption. "Consumers might over-consume a productwith the idea that it is healthyand as a consequence, consume a high amount of fiber; so the type of fiber used should not have any limitations on consumption amount nor should it have side effects," she advised.

The production process  brings additional concerns . Yazbek argued the fiber should not negatively affect the production process, noting acacia products can be easy to use. "The fiber should also not be affected by the production process, so it should be stable to heat, shear and pH when required," she added. Depending on the product, hygroscopicity (readily taking up and retaining moisture) may be an issue and should also be considered when developing a product. "Some products, like the ones packaged in a canister, that are opened and closed several times or in single-dose sachets require a fiber that is not hygroscopic and one that will taste good when consumed with water or mixed to a food." Beyond food and beverage applications, she said the primary challenge for supplements is offering a product that is easy to use, promotes a real health benefit and does not bring any side effect. 

Arnold stressed the importance of picking a fiber that easily incorporated into the product without impacting its color, flavor, texture or  stability.  "Though most prebiotic fibers are stable, some break down when exposed to acidic conditions, such as fruit juices," she said. "The key is a case-by-case product assessment to ensure the prebiotic fiber remains functional after manufacturing and during storage."

One unique challenge for prebiotic fibers is in combination formulas with probiotics. "Because probiotics are living organisms, much more care is required when formulating," Robinson said, noting a primary concern is water activity. "The probiotic supplement must remain dormant until taken, so anything, including prebiotic fibers, added to the probiotic in a formulation must have low-water activity so the bacteria can't become active prematurely." He noted most probiotics also require refrigeration to protect and preserve the live bacteria. Probiotics generally have a shorter shelf life than prebiotic fibers, so when combined into a single product, the shelf life of the fiber is limited to the shelf life of the accompanying probiotic, Robinson advised.

Yazbek pointed to both concerns and advantages for combination pre-/probiotics.  "Some prebiotics are hygroscopic, which would be detrimental to the shelf life of the probiotic," she said. "However, you might find a synergetic effect when using both products together.  For example, acacia gum has the ability to protect some strains of probiotics, extending their shelf life."

While consumer awareness of newer fiber types and new developments in the health benefits of fiber intake go beyond digestion, formulators and ingredient suppliers are busy tackling the challenges that arise with the expanding number of applications and formulations for fiber ingredients. Novel fibers, such as prebiotics, appear on the rise, but they carry additional requirements, especially when using in combination with probiotics. Formulators have much to consider, including hygroscopy and texture, when using fiber ingredients, but careful choreography of all the factors will strengthen  formulas and keep the fiber momentum moving along.

More Heart, Digestion Content

Fiber and prebiotics are great for heart and digestive health. For more information on these two health conditions and how dietary supplements can help boost them, check out INSIDER's content library on Heart Health and Digestive Health.