Hydrocolloids: Gum control in a low-carb world
Formulators turn to hydrocolloids for their useful functional properties without contributing to "net carbs."
By Kantha Shelke, Ingredients Editor
The growing demand for food products that not only control calories but also nourish and taste good has created newfound respect for gums and hydrocolloids among food formulators.
Made up of proteins or carbohydrates, these multifunctional ingredients compound with water (as their name suggests) to achieve their functionality and help resolve a myriad of formulation issues. Generally colorless and bland, gums and hydrocolloids are convenient and versatile solutions for sensory enhancement, calorie reduction, shelf-life extension and cost reduction.
Food formulators today are challenged to remove, reduce or replace a ingredients to create foods that go beyond the low-carb or trans-fat free demands resulting from emerging regulations, changing trends in nutrition and growing consumer awareness of what's healthful. But food reformulation entails much more than simply replacing an ingredient or two -- as one would when replacing raisins with cranberries in a granola mix. Developers must ensure the substitute ingredient matches the functional and nutritional requirements of the one that is being replaced without negatively impacting the taste of the original food product.
The anticipated sensory pleasure conveyed by the appearance and packaging may entice consumers to try foods for the first time, but taste constitutes the real seal of approval and the reason for repeat purchase.The right gum for the job
"Starch, particularly modified starch, is the most widely used hydrocolloid in the food industry and accounts for more than three-fourths of total hydrocolloid use by volume," says Dennis Seisun, CEO of IMR International (www.hydrocolloid.com
), San Diego. "Gelatin, a unique protein, ranks a distant second in this ingredient category made up predominantly of polysaccharides. Gelatins and starches account for more than 50 percent of hydrocolloid value in North America."
Sophisticated manufacturing has created a number of novel functional proteins and polysaccharides as part of tailored texturizing and stabilizing systems.
Why hydrocolloids are ideal
for low-carb applications
Food processors acknowledge that controlled-carbohydrate diets certainly have passed the "fad" test and are becoming a way of life for many. But these diets challenge not only the beliefs of modern nutritionists, but also the skills of food product developers.
Just as diets such as the Atkins (www.atkins.com), South Beach (www.southbeachdiet.com) and the Hamptons (www.hamptonsdiet.com) solve several problems for consumers battling the bulge, hydrocolloids solve problems in formulating products to meet these diets.
1. Dieters experience rapid weight loss, first from body water and then from stored fat, without loss of muscle tissue. [These diets are based on the premise that limiting carbs that supply blood with glucose compels the metabolic pathway to break down fat to provide basic fuel to the brain.] Most hydrocolloids are non-digestible polysaccharides and fit in nicely in low-carb formulations.
2. The higher fat and protein content of these diets satisfy appetites so low-carb dieters rarely experience hunger pangs between meals. [Protein and fat remain in the stomach longer than do carbs; and proteins convert to glucose more slowly than starches do to maintain blood sugar levels.] The soluble fiber content of hydrocolloids slows transition rate in the gastrointestinal tract and helps with the feeling of satiety.
3. Most important of all, low-carb diets have reintroduced taste and pleasure from foods that often were forbidden to those wishing to lose weight. [But consumers, wary of the long-term effects of consuming high protein foods, are demanding healthful foods that will not make them fat.] By contributing smooth mouthfeel and slowing flavor release, hydrocolloids help enhance the taste of low-carb/low-fat versions of traditional foods.
Many food industry analysts continue to be surprised by the growing popularity and success of the reduced-carb segment. Sales of low-carb products and related weight loss products and services are currently estimated at more than $40 billion. Marketdata Enterprises Inc. (www.mkt-data-ent.com), Tampa, Fla., estimates this market to reach almost $50 billion by 2006.
The unique and unifying characteristic of hydrocolloids is their ability to interact with water and form gels at very low concentrations. Gels are essentially three-dimensional interconnected molecular networks that exhibit varying degrees of strength, stability and ability to entrap water and manage its migration.
Another common characteristic of hydrocolloids is their tendency to form colloidal solutions. Distinctly different, colloidal solutions are relatively stable and generally viscous. In colloidal solutions the hydrocolloid particles retain a measurable size and may be separated from their dispersing solution by passing through a semi-permeable membrane.
The food industry has a wide range of hydrocolloids to choose from including agar, alginates, gum arabic, carrageenan, cassia, carboxy methyl cellulose, gelatin, gellan, guar, karaya, konjac flour, locust bean gum, methyl cellulose and hydroxypropyl methyl cellulose, microcrystalline cellulose, pectin, starch, tara, tragacanth and xanthan. They can be used alone or in tailored blends.