From "taking it out" to "putting it in," product development concepts are changing. For several decades, formulating nutritionoriented bakery products meant taking out as much as possible to achieve products with "reduced" or "low" claims. Recently, however, the industry experienced a paradigm shift: Formulating for nutrition now means adding as much as possible to a product to support "good" and "excellent" source claims without an undesirable effect on the sensory characteristics. Probiotics and prebiotics such as those listed here (see Page 92) form a "happy couple" now making a strong appearance in the functional bakery products arena.
THE HEALTH FACTOR
According to a study published in the February 2001 issue of American Journal of Clinical Nutrition (Vol. 73, No. 2, Supplement Pages 361 to 364), numerous health effects are attributed to "friendly" intestinal bacteria, also called probiotics. Many different studies document that probiotics 1 — lower the frequency and duration of diarrhea associated with antibiotics, rotavirus infection, chemotherapy and, to a lesser extent, traveler’s diarrhea; 2 — stimulate humoral and cellular immunity; and 3 — decrease unfavorable metabolites, for example, ammonium and precarcinogenic enzymes in the colon.
Other studies provide evidence of the health effects of probiotics for reduction of Helicobacter pylori infections, reduction of allergic symptoms, relief from constipation and irritable bowel syndrome, increased mineral absorption (calcium and magnesium) to improve bone density and stability and cancer prevention. All these effects cannot be explained by a unifying hypothesis based on a single quality or mechanism, so more research is needed to understand the health properties of pro- and prebiotics.
The beneficial influence of certain living bacteria consumed as part of foods has been known for more than 100 years. But it was not until recent decades that new knowledge has brought intestinal microflora into the spotlight. In Europe, the largest group of functional foods consists of probiotic, prebiotic and synbiotic foods targeted to improve the gut microbiota and, by doing this, improve human health and well-being. (Synbiotic foods contain both probiotic and prebiotic constituents.)
Japan’s unique Foods for Specified Health Use (FOSHU) category came into effect in 1993, and nearly 70 different items have qualified based on a list maintained by the Japanese Department of Health of approved foods and ingredients for which enough scientific evidence supports their health claims. The FOSHU list includes several pro- and prebiotic ingredients, and many containing prebiotics are now on the Japanese market; however, no foods containing probiotics have yet received approval.
In the US, however, this trend has been slow to catch on, but it seems that the market is now ripe for change. According to consumer research reported by Susan Potter, Ph.D., R.D., vice-president, health and nutrition sciences, Tate & Lyle, Decatur, IL, 67% of US respondents rated fiber as useful in helping to maintain or control digestive health and the immune system. Also, Tate & Lyle’s consumer research showed that 62% of US consumers found the concept of products that promote a healthy digestive system appealing. Furthermore, consumers were receptive to a range of products that helped boost the immune system through an optimum combination of vitamins, minerals and fiber: 67% of US consumers found that attractive. In addition, 72% of US consumers were attracted to products that contained an effective mix of vitamins, minerals, fiber and protein to aid children’s development. However, it is important to note that 72% of people surveyed in the Yankelovich Monitor Perspective (Food for Life, 2006) said that if food didn’t taste good they wouldn’t eat it, no matter how healthy or nutritious it was. The same survey found that 79% believed food companies should develop healthier foods that taste better.
WORKING PREBIOTICS IN
The typical prebiotic is a fermentable fiber, and there are many choices, both soluble and insoluble, that find use and also provide the health benefits associated with fiber. However, formulating with these ingredients may be a balancing act between adding enough to achieve the functional properties without a negative impact on the sensory characteristics of the product. In addition, to perform as a prebiotic, the ingredient should be able to withstand, first, food processing and, second, digestion in the upper gastrointestinal tract.
One formulation challenge to overcome is that fiber absorbs a large amount of moisture and forms a matrix with it. This may affect the quality of the final product as well as the processing parameters. When insoluble fibers are used, moisture levels and mix times should be increased to account for the fiber’s ability to trap moisture. In addition, increased baking times and temperatures will be needed to drive off the lingering moisture.
According to Joseph O’ Neill, executive vice-president, sales and marketing, Orafti Active Food Ingredients, Malvern, PA, formulating high-fiber bread products with traditional fibers will often result in significant water uptake and the formation of sticky doughs. Orafti recently introduced Beneo HPX and Beneo L95, high performance inulin ingredients for bakery and snack applications. Mr. O’Neill stated that standard Beneo inulin may be slightly hydrolyzed by yeast enzymes; however, Beneo HPX undergoes less hydrolysis by yeast enzymes compared to standard inulin. It also allows controlled water uptake in high-fiber bread with improved dough handling. Standard Beneo inulin is slightly sweet, while Beneo HPX has no sweet taste which is of particular benefit in highfiber breads where the use of classical fibers may be limited, continued Mr. O’Neill. Beneo L95 may be used in cereals and snack foods. It is a sweet fiber syrup with excellent browning characteristics. Fibers such as inulin and oligofructose work very well in conjunction with high-intensity sweeteners such as polyols and contribute to Maillard browning, which is often lost in reduced-sugar or sugar-free products.
One concern about formulating with prebiotic fibers is the risk of gastrointestinal discomfort. However, Mr. O’Neill countered, "Prebiotic fibers like Beneo inulin and oligofructose improve digestive regularity and are used to relieve constipation. Fiber intake in the US is low compared with our counterparts in Europe; therefore, as one increases the fiber load, our bodies need to adapt to the increased fiber levels. When formulating, a good guideline is to stay within the ‘good source’ and ‘excellent source’ parameters for fiber, which is 2.5 to 5 g per serving size.
"All fibers when fermented produce gas as a by product of microbial fermentation," he continued. "Longer chain length inulin such as Beneo HP, HP Gel and HPX is slower fermenting than oligofructose and therefore has improved tolerance. Formulators will often use a combination of fiber sources for improved tolerance. In addition, tolerance is often a function of water activity in the finished products. High-solids formulations like snacks, cookies and breads when made with high fiber levels will be better tolerated than beverage products with equivalent fiber levels."
The use of a combination of prebiotics with slow fermentation rates may also help reduce negative side effects such as gas and bloating. For example, arabinogalactan (at 2 to 10% in bakery products) ferments very slowly, so discomfort is not evident. Polydextrose also has sustained fermentation throughout the colon helping avoid the side effects. The approach taken by Cargill, Minneapolis, MN, is to combine fibers for multipurpose functionalities. A recent project at Cargill developed Fiber Krunch, a high-fiber inclusion (35%) that resembles crisped rice. The primary fiber source is resistant starch, but the product also includes inulin. The use of an ingredient such as Fiber Krunch can be a convenient way to add both insoluble and soluble fiber to bars and cereals without significantly altering the overall formulation or negatively impacting product quality.
According to Wendy Erickson, the bakery, snacks and cereal technical manager for Cargill Texturizing Solutions, prebiotics have been used in bakery and snack products to increase fiber content (soluble fiber or resistant starch). However, work is needed to link clinical health benefits to prebiotics. Probiotics have typically been used in dairy applications continued Ms. Erickson. Preand probiotics may have overlapping functions, but their roles are different. A combination of pre- and probiotics may prove synergistic.
Recently, Danisco developed strawberry yogurt-filled confections and vanilla wafers that contain the company’s probiotic culture, HOWARU Dophilus, and its prebiotics, Litesse and Lactitol, which are marketed by Danisco Sweeteners, Elmsford Park, NY. The combination creates a synbiotic effect with digestive health benefits. Danisco’s Mind Body Synbiotic Confections and Wafers also have the benefit of Litesse polydextrose, which is high in fiber. Litesse and Lactitol can help reduce sugar, lower glycemic response and reduce calories. HOWARU Dophilus is a probiotic strain shown to balance intestinal microflora, improve digestive health, and ferment prebiotics.
Tate & Lyle recently launched a new service that enables food and beverage manufacturers to create products that are packed with additional nutrients but taste as good as regular brands. Tate & Lyle’s ENRICH service is focused on three main areas: digestive health and immunity, obesity and weight management and children’s health. ENRICH for digestive health and immunity comprises a range of ingredients, including prebiotic fibers, probiotics, vitamins and minerals that can be used in consumer products that help to promote healthy digestion and may boost the immune system. Tate & Lyle is also developing a broad range of dietary fiber ingredients for inclusion in ENRICH systems. The ENRICH solutions also include a range of vitamins and minerals and are formulated to provide synbiotic benefits, for example, prebiotic fiber in combination with probiotic cultures.
Until very recently, addition of probiotics was limited to refrigerated products to ensure viability of the live bacteria. However, new technologies such as encapsulation make it possible to develop synbiotic products in other categories, including baked foods. In a recent review published in the May 2007 issue of Trends in Food Science & Technology (Vol. 18, No. 5, Pages 240-251), authors Anil K. Anal and Harjinder Singh showed that various hydrocolloids can have potential as probiotic encapsulators. These included alginate, chitosan, carboxymethyl cellulose (CMC), carrageenan, gelatin and pectin. These ingredients are applied using spray- and freeze-drying techniques. The reviewers noted that, while such techniques may yield large quantities of material, the encapsulated bacteria are not well protected from temperature and extremes of external water concentration. However, the use of ingredients such as trehalose can improve bacterial survival in processing conditions.
Another approach for probiotic encapsulation is the use of lipids with high melting points that provide lowmoisture conditions and an anaerobic environment for probiotic bacteria that may improve thermal stability. Soy peptides, whey protein and prebiotic fibers can also be used for bacterial encapsulation.
Commercially, Lallemand, Montreal, QB, has developed a way to use coated probiotics in chocolate, which could be used as a filling in biscuits, nutrition bars or chocolate drops for addition to breakfast cereals. Crucially, the bacteria need to be added after cooking because they do not survive heat. Moreover, the chocolate vector is said to be ideal since chocolate does not require much processing and can be added to several finished products. Chocolate has also been a focus for DSM Food Specialities, Parsippany, NJ; a nutrition bar under the Attune brand contains DSM’s Lafti probiotic ingredients recently launched in the US and carries five times the amount of probiotics as yogurt.
As research continues in this area, new alternatives will be available for the baking and snack industry. The opportunities in this area are undeniable. In fact, the market of products with prebiotics and/or probiotics continues to figure strongly as consumer awareness of good digestive health continues to grow. Whether these products are used for increasing fiber intake, improving calcium and magnesium absorption, improving bone health, promoting weight loss and satiety or improving the immune function — or a combination of all of the above — the inclusion of these ingredients in the bakery will definitely prove to be healthy business.