Nov. 1, 2011
by Laurie Gorton
Usually, steady supply and good availability characterize the market for gums and hydrocolloids. But unusually, current circumstances have sent formulators scrambling to replace one of these useful natural materials: guar. Such conditions will likely persist for a long time to come, and that fact changes the way formulations will be balanced.
Food gums manage moisture and texture in a broad spectrum of baked goods and snacks. The ability of these specialized ingredients to build structure also helps satisfy demand for gluten-free products, yet there may be even bigger roles for such highly functional materials.
“No question, the future for innovation in hydrocolloids lies beyond simply thickening, gelling or stabilizing,” observed Dennis Seisun, principal, IMR International, San Diego, CA. He summarized developments described at this year’s Hydrocolloid Conference: “Nutritional aspects, along with physiological effects on satiety, cholesterol control, probiotic and prebiotic effects, are all being researched intensively.”
Guar’s tight supply is the only black cloud on the horizon. Normally plentiful, guar recently was adopted by the oil and gas industry as an aid to horizontal drilling. It thickens drilling solutions just as well as it thickens foods, and it has become a game-changer in drilling technology. “Oilfield demand for guar is definitely the prime cause of its tightness in supply,” Mr. Seisun said. (See web exclusive “What About Guar?”
Food gums act as water-control agents by altering the viscosity, or resistance to flow, of a system or by forming gels. Also known as hydrocolloids, these ingredients come from plant exudates, plant and seaweed extracts, plant seed gums, plant cellulose, microbial fermentation and animal tissue. Gelatin, derived from animal collagen, is a protein, but all other common hydrocolloids are polysaccharides.
Depending on their use, gums act as stabilizers, film formers, suspending agents, whipping agents, coating agents or crystallization inhibitors. These materials operate over a broad range of functionalities. Some form gels; others do not. Some are soluble at room temperatures; others require heat. Some are stable at low pH; others work better under neutral to alkaline conditions. Still others require the presence of potassium or calcium ions to achieve the desired results. Most, but not all, are thermo-reversible.
Typical usage levels come to less than 1%, often in the range of 0.1 to 0.3%. “But there is no one-size-fits-all answer,” said Harold Nicoll, marketing manager, TIC Gums, White Marsh, MD. “As far as limits, there are some. Overuse of gums will literally weigh a product down.”
The newest is flax. OptiSol 5000, a flaxseed-based ingredient system offered by Glanbia Nutritionals, Fitchburg, WI, can manage moisture, extend shelf life and give dough more workability and extensibility in applications such as tortillas, pizza dough, fresh breads, baked bars, cookies and muffins.
“Not only does it have these functional properties, it can also be considered a health-and-wellness ingredient,” said Marilyn Stieve, Glanbia Nutritionals’ business development manager. Its flaxseed source confers high levels of alpha-linolenic acid (ALA), an omega-3 fatty acid. Foods that contain 0.65 g OptiSol 5000 per serving can make a “good source” claim for ALA on package labels.
Also new — or rather, newly recognized — is the role of gums as dietary fiber. For example, Nexira (previously known as Colloides Naturels), Somerville, NJ, selected a specific range of acacia gum that guarantees 90% soluble dietary fiber content, according to Teresa Yazbek Pereira, the company’s vice-president and sales director. “In bakery, Fibregum delivers technical and nutritional benefits at the same time,” she said.
Acacia in this form is a proven prebiotic at 6, 10 and 15 g per day and exhibits a high degree of gastrointestinal tolerance, promoting “gut comfort” and well-being, according to Ms. Yazbek Pereira. Usage levels of less than 1% provide the technical benefits of moisture stability, freshness and dough conditioning. Its film-forming properties protect against moisture loss and oxidation.
Co-processed acacia gum and wheat fiber, Equacia from Nexira, mimics fat’s texture and, at 1 to 1%, can substitute for half the fat in cookie, muffin, cake and bread formulations and extend eggs, according to Ms. Yazbek Pereira.
Polydextrose, a randomly oriented polymer composed of glucose chains, has a water-binding effect similar to hydrocolloids in baking applications and assists in management of water activity, according to a team of food experts from Danisco USA, New Century, KS: Helle Tornas, industry manager; Steve Mallory, application specialist, bakery; Troy Boutte, manager, bakery, fats and oils; and Janelle Crawford, manager, industry marketing. Benefits cited for the company’s Litesse polydextrose include gastrointestinal tolerance compared with other soluble fibers. It can support prebiotic content claims and is easy and cost-effective to use in bread, bars, cereals and other applications.
Psyllium, extracted from the plant’s seed coat, is well-recognized for its dietary fiber content — two-thirds soluble and one-third insoluble — but it is also a gelling agent. “It forms a biphasic system upon hydration, where the soluble fraction creates a viscous solution, and the insoluble fraction will eventually settle,” said Firth K. Whitehouse, PhD, global applications and marketing manager, Caremoli USA, Inc., Ames, IA. She recommended that it be dry-blended with other ingredients prior to hydration. At 1%, it will retard staling in bread applications.
Significant interest in gums centers on gluten-free formulations. “Gums can mimic some of the functions of gluten in bakery applications,” Mr. Nicoll said. “Gums will help the formulation from just falling apart.”
Viscoelastic gums like xanthan can replace strength and elasticity lost when formulating without gluten, he explained. Additionally, xanthan gum traps air produced during fermentation and baking bread. The trapped air helps give the bread its form and support structure. Gums also help replace cohesiveness and flexibility of dough lost without gluten — characteristics that assist preparation of pie dough, biscuits, pasta and cereals, among others.
In gluten-free applications, Mr. Nicoll reported, combinations of konjac and xanthan or locust bean gum produce viscoelastic gels capable of replacing some of the strength normally provided by gluten. Sodium alginate forms thermally irreversible gels with calcium, which benefits both gluten-free and gluten-containing bakery applications.
“Any baker working with gluten-free applications knows that working without gluten is problematic,” said Josh Brooks, vice-president, sales, Gum Technology Corp., Tucson, AZ. The company’s specially developed stabilizer replaces gluten’s elasticity, making the dough or batter easier to work and providing the structure that entraps the gas responsible for leavening the product. “Stabilizer ST-101 imparts an appealing texture to the finished product versus what might have been a cardboard-like baked good,” he said.
The Danisco experts also identified xanthan and xanthan/alginate blends that help create the structural network needed when replacing gluten in baked foods.
“Addition of xanthan gum will increase moisture retention for better mouthfeel and delayed staling,” said John Reidy, market development manager, health and nutrition, Jungbunzlauer, Inc., Newton Centre, MA. Its viscoelasticity helps increase volume and develop fine, uniform crumb structure. He observed that the gum’s pseudoplastic flow eases handling during processing.
The choice of hydrocolloid affects more than just gluten-free formulating; it’s also key to meeting growing demand for vegetarian and vegan foods as well as products that support health and wellness. “The challenge of substituting for gelatin,” explained Rodger Jonas, director of national sales, P.L. Thomas, Morristown, NJ, “and supporting moisture control in gluten-free bakery goods, meeting organic application needs and addressing new application development for nutritional products have been the critical areas of our focus in bakery.”
In blends, gums often exhibit synergistic effects. “Individual gums such as xanthan, tara, guar, fenugreek, alginate, konjac and carrageenan can all be used in baked goods to help the baker solve a variety of issues,” Mr. Brooks said. “Typically, combining one or more of these individual gums creates a more highly functional stabilizer.”
For example, Gum Technology’s Coyote Brand Stabilizer ST-101 combines xanthan and guar. The blend’s functionality exceeds that of its components and improves texture in the dough and cell structure in the finished products as well as retaining moisture and extending shelf life, all at very low usage levels: typically 0.05 to 0.35%.
Such control over moisture seems to counteract starch retrogradation in muffins and cakes and prevents sugar bloom, Mr. Brooks observed. Controlling moisture also supports freeze-thaw stability and extended shelf life in frozen baked goods.
Konjac and tara react synergistically in the company’s Coyote Brand Kt-MS to provide a creamy and smooth texture in cheesecakes and cream pie fillings, according to Mr. Brooks. Carboxymethyl cellulose (CMC) and acacia gums combine well in fondants to improve pliability and prevent drying and cracking. Agar and locust bean gums work well together in glazes to prevent drying, and since agar has a high melting point, it helps stabilize glazes on products such as donuts or pastries that sit under heat lamps.
As sustainably sourced products of nature, food gums lend themselves to finished products labeled natural. They also enable clean-label formulations. Ms. Yazbek Pereira explained that Nexira’s Fibregum functions as an emulsifier, eliminating chemical or GM-containing ingredients, thus cleaning up product labels. In addition, the acacia-based systems reduce breakage of tortilla chips, crackers, pita chips and other thin snacks. “They improve stability and increase crunchiness,” she said.
Specialty cellulosic gums such as CMC, hydroxypropylmethyl cellulose (HPMC) and microcrystalline cellulose (MC) feature high water-holding capacity. “This allows greater moisture in cakes, breads, tortillas and other bakery items leading to greater softness and less drying and cracking, thus prolonging the shelf life,” said Laurie Kronenberg, new product leader, food and pharmaceutical, Ashland Specialty Ingredients, Wilmington, DE. And yield increases because gums permit greater water addition to batters and doughs.
Two such gums, Ashland’s Benecel MC and HPMC, provide unique thermal gelling activity, according to Ms. Kronenberg. They also promote and stabilize foams, suiting their use in whipped toppings and egg reduction or replacement. These properties also work well in gluten-free baking to add aeration and stabilize volume in the absence of gluten.
A structurally modified form of cellulose, UltraCel from Watson, Inc., West Haven, CT, is dissembled to the level of microbfibril, a nano structure that readily participates in the formation of polymer gels, according to Michael K. Weibel, Watson’s vice-president, R&D. This alteration helps it interact with most gums and, in particular, with the hydrated gluten network in dough.
UltraCel gums are particularly useful as shortening replacements for flatbreads such as tortillas, pizza crust, pita bread and wraps as well as cookie and cake products, Mr. Weibel observed. “Typically, fat reduction requires mass replacement with water and textural augmentation with gums,” he explained.
Describing gums and hydrocolloids on food packaging is fairly simple. “In general, all of these gums are labeled as their name implies — for example, as guar gum, xanthan gum, tara gum, psyllium husk fiber and locust bean gum,” Dr. Whitehouse explained.