Trends in Starches and Stabilizers for
Application in Organic Foods
By Jacqueline Andreas and Joe Lombardi
Reaching and satisfying a wider audience of consumers is a challenge facing manufacturers of processed organic foods. Today’s consumers are seeking clean-labeled, nutritionally balanced, easy-to-prepare meal solutions to meet the needs of a hectic lifestyle. That is why the rapid growth in refrigerated dairy, frozen and refrigerated meal solutions, snacks and bakery items in the mainstream food industry is reflected in the same categories of organic foods.
To be successful, organic foods must meet the demanding product quality standards for taste, texture and convenience expected by today’s consumers. One of the most important challenges facing the formulator in meeting these expectations is the appropriate selection of ingredients to thicken, texturize and stabilize organic foods. The choice of functional ingredients that are certified organic or simply approved for use in organic food is limited and defined by the U.S. Department of Agriculture (USDA) National Organic Program (NOP). This includes some native starches, flours and gums.
Starches, Stabilizers and the NOP
Formulators of prepared organic foods must meet strict labeling regulations that define what ingredients—from flavors to starches—are allowed in certified organic products. The labeling standards (www.ams.usda.gov/nop/IndexIE.htm), as defined by the Organic Foods Production Act and the NOP, are intended to assure consumers that the organic foods they buy are produced, processed and certified to consistent standards.
The organic labeling requirements of the standard are based on the percentage of organic ingredients in the product:
1. Products labeled as “100% organic” must contain (excluding water and salt) only organically produced ingredients.
2. Products labeled “organic” must consist of at least 95% organically produced ingredients (excluding water and salt). Any remaining product ingredients must consist of nonagricultural substances approved on the National List or non-organically produced agricultural products that are not commercially available in organic form.
3. Products meeting the requirements for “made with organic ingredients” must contain at least 70% organic ingredients and can list up to three of the organic ingredients or food groups on the principal display panel.
4. Products that contain less than 70% organic ingredients would be allowed to list the organic items in the ingredient panel only. These products cannot use the term organic anywhere on the principal display panel.
The National List aids food formulators in determining what ingredients may or may not be used in processed organic foods. Examples of ingredients on the National List that may be used for thickening and stabilizing in processed foods labeled as “organic” or “made with organic” include corn starch (native), Xanthan gum, pectin, and water-extracted gums such as arabic, guar, locust bean and carob bean. However, according to the guidelines, if an ingredient is commercially available as organic it must be used preferentially over the non-organic form of the ingredient. For example, native cornstarch is listed in the National List as allowed in foods labeled as “organic” or “made with organic”; however, because organic corn starch is readily available, processors are directed by regulation to use the organic form of the ingredient.
Modified food starches are not included on the list of approved organic ingredients and thus, formulators must use native starches and/or approved gums to thicken, texturize and stabilize their products.
Native, Modified and Functional Native Starches: Definitions and Differences
Native starch is the granular starch component recovered from the original plant source by typical milling and that has not undergone any additional treatment or modification. Common starches are obtained from variety of cereal grains such as corn, wheat and rice, and from tubers or roots such as potato and tapioca. Starches isolated from different sources will vary in taste, texture and thickening properties. Some of the more common types of native starches used are derived from corn, waxy maize and tapioca.
Figure 1 illustrates the textures associated with different native starch bases, including native corn starch, waxy maize, tapioca and functional native. Native corn starch forms an opaque, gelled paste that has a slight cereal flavor. Waxy corn starch results in a thin, cohesive paste with a slight cereal flavor. Tapioca starch produces a clear, cohesive paste that gels slowly over time, and a functional native starch contributes a short, smooth texture to a product.
Of course, these native starches are applied to a variety of food formulations, depending on the taste, texture and thickness the formulator wants in the final product. One might use a root-type starch, for example, if the formulator does not wish to add much additional flavor to the final product. For puddings or dessert creams, one might select a waxy maize starch, which yields highly viscous, clear pastes to attain the desired texture, whereas for ready-to-eat, prepared-frozen or canned foods, the formulator might opt to use a native corn starch for high thickening characteristics. Applications of organic potato starch to dehydrated soups and sauces can improve water binding and consistency in the product, or improve the suitability for extrusion in the case of snack foods. Simi-larly, native gums, when used as the sole stabilizer in a food, typically will not provide desired texture and performance in the product. Often, a starch/gum combination is preferred by the formulator to produce the ideal texture and stability in a food.
Each has its unique properties, but all have one thing in common: Native starches lack processing (cooking) tolerance, which can result in a loss of viscosity, unpredictable yields and poor end-product textures in those types of food formulations that require cooking. Since native starches typically do not possess the functionality of modified starches, organic food formulators who wish to develop ready-to-eat, retort and similarly processed products face a challenge. Additionally, there is variation involved with different types of food processing that the formulator must take into account when developing an organic final product. For example, food processing can range from an instant process that does not involve any heat or shear such as with an instant soup, to an easy-to-cook stovetop preparation such as a stovetop pudding, to a high-heat sterilization process such as yogurt. Table 1 lists different types of food applications along with process conditions typically associated with that application and indicates what attributes the starch would contribute to the final product.
The functional properties of native starches are improved by modification. This explains why the majority of products placed on grocery store shelves contain modified food starches. The modifications enable the starch to better withstand the heat applied to food products for sterilization, the shear associated with various types of processing equipment, and the acid content of food systems such as the acids from fruits in pie fillings or the vinegar in salad dressings. In addition, certain starch modifications enhance the refrigeration and freeze/thaw stability of starches so that water separation does not occur while the food product is being stored in the retail market.
It is sometimes assumed that the word “modified” in modified food starch refers to a genetic modification of the starch. This is not the case. The term “modified food starch” does not imply that the source plant’s genes have been altered in any way. Rather, it refers to a number of USDA/U.S. Food and Drug Administration (FDA) approved chemical modifications that are applied to the starch granule after extraction from the plant. The most common type of modification is a treatment of the native starch with extremely small levels of these food-approved reagents. For example, one, called “crosslinking,” controls granular swelling and produces a starch that can withstand high temperatures, high amounts of shear and acidic conditions. However useful and safe they may be, modified food starches of any type are not allowed in any category of organic labeled foods.
As noted, it is critical that starches used in manufactured foods exhibit process tolerance because of the high heat applied to sterilize foods, the shear associated with various types of equipment, and the acid content of food systems. A recent trend in organic product formulation is the availability and application of functional native starches, which offer a solution to the challenge of formulating prepared foods with native starches. These starches differ from the common native starches by offering the process tolerance and viscosity consistency typical of modified food starches while not being modified themselves.
Starches that do not have process tolerance will lose their viscosity very quickly during cooking and result in poor product. Studies show that traditional native starch reaches its peak viscosity and breaks down very rapidly with the application of steady heat, resulting in thin viscosity. Functional native starch has been shown to hold up to the steady heat over time and maintain a consistent viscosity. Due to this ability to withstand processing, functional native starches result in a smooth, short texture.
Since functional native starches are produced through a physical process, they can be applied to a variety of native starches—rice starch, corn starch, tapioca starch and potato starch—to take advantage of their unique characteristic.
Cold-water-swelling starches, which do not require heat to become functional, also are available for making easy-to-prepare dry products such as soups, puddings and sauces. In addition, because these products are minimally and only physically processed and since functional native starches are now available in certified organic versions, they are considered approved for use without usage limitation in all categories of organic foods.
Effective Starch Selection
Selecting the appropriate ingredient and/or combination of ingredients to thicken, texture and stabilize the food system can be challenging and very time-consuming for the formulator. Ingredient suppliers within the organic food industry can be a great help in providing support throughout the development stages and assist processors in launching new products in the quickest and most efficient way possible.
Jacqueline Andreas is a food scientist in the Food Products Division of National Starch, a leader in the development of starches for foods for more than a century. Andreas can be reached via e-mail at email@example.com.
Joe Lombardi is Marketing Program Manager, Natural Polymers Group with National Starch. He can be reached at firstname.lastname@example.org.