Non-digestible hydrocolloids such as xanthan, guar and pectins are also suitable replacements for simple carbohydrates that help control moisture in soluble and non-soluble applications such as pie fillings and processed meats.
Modern manufacturing practices are practically built around flour, making it a difficult ingredient to substitute for in the production of low-carb foods.. Its solubility is excellent for the right level of thickening and managing emulsification without making the food product too thick or tasteless.
For other hydrocolloids that are difficult to dissolve or disperse in limited moisture conditions, polyols and humectants such as sorbitol and glycerin are often used to aid in dispersion.
Whole grains and fibers
Replacing refined grains with whole grains can provide a concentrated source of important nutrients and dietary fiber while also reducing the glycemic load. Educated consumers are beginning to seek out the words stone ground, whole wheat or whole grain (not whole meal) on the ingredient list of products.
But a word of caution: Just because a food is made from whole grain ingredients does not mean it is also lower in glycemic index than its counterpart made from refined ingredients. For instance, pasta made from refined traditional semolina has a lower glycemic index than whole wheat pasta. Light rye flour, cornmeal and rice flour have high glycemic values and are more likely to raise blood sugar. Plus, rice flour has virtually no dietary fiber.
Spelt is an obscure but good whole grain, low-glycemic replacement for refined flour. Spelt flour contains more protein and fiber than wheat and may substitute for whole wheat flour because it is lighter â€“ a fact that is being capitalized on by Barilla America Inc. (www.barilla.com), Iowa City, Iowa, with its new Barilla Plus pasta.
A new line of dietary fibers from the hulls of Canadian yellow peas is another healthful alternative to refined flour in low glycemic foods. Parrheim Foods (www.parrheim.com), Winnipeg, Manitoba, has created Centara III, Centara IV and Centara 5, natural food-grade vegetable fiber products that offer an means of fiber enrichment.
GTC Nutrition (www.gtcnutrition.com), Golden, Colo., offers Natureal oat bran concentrate, which provides 15 percent oat beta-glucan for glycemic control. Natureal can be used to replace more quickly metabolized grain flours in a wide variety of applications for a minimal cost impact.
The science and art of substitution
Food formulators face daunting challenges in the current environment in which their employers are focused on replacing, reducing and eliminating many ingredients in an attempt to create “healthful foods” that appeal to consumers. But food reformulation is a complex process and requires more than simply replacing the incumbent with a new ingredient.
Seasoned formulators are cautious about suppliers’ promises of “volume for volume” or “weight for weight,” and they review each substitution in terms of its impact on functional ingredients such as texturizing, leavening and flavoring agents and quality of the end product. The key is not in finding mere equivalents for flour but to understand exactly what is happening in the food system and how best to replace all functionality and quality aspects with the replacement ingredients.
Fiber, while a nice alternative to simple carbohydrates, can greatly affect the texture of the end product because of how it interacts with water. Processing conditions can, for example, affect ingredient functionality â€“ finer particle size can increase its affinity for water; heat treatment can decrease its affinity. Processing also can impact how the ingredient interacts with other ingredients, such as spices and flavors. Fiber of fine particle size generally requires additional spices.
Even crop conditions can affect the proportion of soluble to insoluble fibers in natural plant-based ingredients, and small shifts in these ratios can have a major impact on the formulation. Formulators also need to understand the role and status of water with the various components of dietary fiber â€“ soluble, insoluble or colloidal â€“ for each phase during manufacturing so as to ensure duplication at the appropriate stages and a final product that matches the traditional counterpart.
Complexity of food ingredients renders the process of formulation largely empirical and accompanied by trial and error. Ignoring this essential concept can cause tremendous failures and costly delays during reformulation. Modern reformulation calls for more than traditional bakery skills â€“ mapping ingredient functionality and interaction with other ingredients is even more critical for successful substitution.