Achieving the Leanest of Lean Ground Beef

Jaclyn Ellis

Introduction

Americans are becoming more and more health conscious, a trend increasingly apparent in the food choices they make each day. In a 2003 Gallup report, 74% of all adults polled were interested in reducing fat in their diets. Since 1999, 75-80% of consumers regularly consume low fat or fat-free products (1). Citing a poor diet as one of the major causes of morbidity and mortality, the 2005 Dietary Food Guidelines stress the importance of a diet low in fat. Total fat intake should represent 20 to 35% of calories; saturated fat should not exceed 10% of total caloric intake (8). Diets high in saturated fat are believed to increase risk of cardiovascular disease, certain cancers, and obesity (2). The guidelines also state that consumers should choose lean, low-fat, or fat-free options when selecting and preparing meats (8).

Beef is an integral part of the diet of many Americans. In 2004, the cattle and beef industry had a $79 billion retail equivalent value, and Americans consumed a total of 27.6 billion pounds of beef (9). Approximately 40% of beef eaten in the United States is consumed at ground beef (3). Ground beef is found in an endless list common dishes, including the “All American” hamburger, casseroles, pizzas, etc. Considering the prevalence of ground beef in the American diet and the heavy consumer demand for healthy products, one might think that a low fat ground beef product would be an attractive, marketable product.

Difficulties in Formulating Low-Fat Ground Beef Products

Translating idea into reality is not so simple a task. Negative sensory qualities have haunted low fat ground beef products. Research indicates that people prefer ground beef with 15-20% fat. Low fat products, with fat contents starting below 15%, tend to have less beefy flavor intensity, juiciness, and tenderness. It has been a challenge to formulate a low-fat ground beef product in which the texture, flavor, and appearance are not compromised. In addition to contributing valuable sensory qualities, fat functions to provide nutrients, namely the fat soluble vitamins A, D, E, and K (1). Another hindrance in the production of quality low fat ground beef has been the expense. Reduced fat meats often cost more to produce than their whole fat counterparts. Finding inexpensive ingredients is the primary obstacle. Some fat replacers are relatively costly (2).

Meat Extension

Meat manufacturers do have options. Adding water and binders to meat is known as meat extension. An economical way to increase yield, meat extension has been around since the 1950s. Nutritional properties remain intact, and the cost is relatively inexpensive. These two advantages make meat extension a practical choice for schools, the military, and other foodservice venues. Starch, gums, and proteins are common binders in meat extensions.

The substances added to meat extensions can contribute to the overall nutritional value of the product. Soy protein is an excellent quality protein and is gaining clout with the American public for its functional properties. Another potential binder, whey is an excellent source of branched-chained amino acids and leucine. Many carbohydrates have the ability to boost the total fiber content when added to meats (2).

Meat extension has some disadvantages. A down-side to water addition is the longer cooking times required. Fat assists in heat penetration. When water is replacing the fat, heat penetration slows, increasing the time needed to reach the proper internal temperature for an adequate thermal treatment. Also, a higher water activity corresponds to an increased risk of microbiological activity. Sugar alcohols may be added to lower the water activity and extend the shelf-life of such meat extensions (2).

The Key Ingredient

There are many fat replacers on the market. They are generally classified by their composition; there are protein-based, lipid-based, and carbohydrate-based. Little to no processing changes are needed to make a low fat ground beef product. The beef is ground twice. In the first grind, the beef is ground alone. In the second grind, the fat replacer, water, and any other ingredients are added.

Protein-based Fat Replacers

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Proteins can be denatured by heat or enzymes so that they behave as good fat replacers (1). Textured vegetable and soy proteins are popular choices, but they are not the only options. Wheat protein, pea protein, and even peanut protein may be textured and used as a fat replacer. Whey protein is showing particular promise as a fat replacer in low fat meat formulations. Whey protein concentrates tend to be less expensive than other fat-replacers. WPCs have good gel-forming characteristics and water-binding properties that blend well with and add moistness to the meat matrix. In sensory tests, low fat ground beef patties formulated with WPC have performed better than other low fat formulations and equal to full-fat patties (4). WPCs may also maximize cooking yield and minimize shrinkage in low-fat formulations. Additions of tripolyphosphates and lactose to the WPC formulations may also improve juiciness and overall acceptability of these low-fat meat products(5). Consumers unaccustomed to soy often complain of an aftertaste when it is used in formulations; in contrast, whey is relatively bland and absorbs fat and binds flavor chemicals readily (2). WPC can be ground in beef directly with water in the powdered form or mixed with the water before grinding. In either case, a drastic alteration in processing methods is not necessary (4).

Fat-based Fat Replacers

Fat-based replacers tend to be either emulsifiers or lipid analogues. Emulsifiers stretch the functionality of low fat levels or can even replace function of fat in combination with other ingredients. Lipid analogues are modified slightly. Usually a substituent is added to the triacyglcerol that makes the fat either partially or completely unabsorbable, resulting in a decrease in caloric content. Fat analogues closely resemble normal fats. They are believed to replace fat weight per weight. Examples include Olestra, Benefat, Enova, and Neobee MLT-B. These products tend to be rather costly.

Carbohydrate-based Fat Replacers

Carbohydrate-based fat replacers mimic fat by binding water, adding bulk, texture, and mouthfeel to products. Processed starches and fibers are often used (1). Starches of various origins appear in processed meats. Cornstarch, rice starch, modified potato, and tapioca are common in meat formulations. Starches chosen must be stable in chilling, freezing, and heating temperatures and at the appropriate pH, and must also have a particle size that delivers the appropriate mouthfeel (1). Fibers are in many ways believed to be functional in that they are associated with a decrease in blood cholesterol levels, and a decrease in blood glucose and insulin response. Fibers also add bulk to the diet, contributing little caloric value (10). They are good ingredients to consider in formulation of low fat ground beef patties. One particular fiber, inulin, is often used in meatless dishes, but can easily be used in meat products. It works well with hydrocolloids, assisting in hydration and contributing to proper mouthfeel (2).

Oatrim, Nu-Trim X, and Z-Trim are newly developed fibers that can be used in processed meats. Oatrim contains a mixture of beta-glucans and amylopectins, and trace amounts of lipids, proteins, and minerals. Nu-Trim X contains solubilized beta-glucans from oat and barley endosperm with reduced cellulose. Z-trim is a zero-calorie fat replacer made from low cost agricultural by-products like the hulls of oats, rice, corn, soybeans, and peas or bran from corn and wheat. The particle sizes of the components are reduced so that they form gels with a smooth texture (2). Rice bran has antioxidant properties and when added to ground beef may retard lipid oxidation, extending the shelf-life of ground beef patties (6). Z-Trim/Oatrim blends may be used in combination to yield acceptable low fat ground beef products. In Warner and Inglett, a blend produced a beef patty with less chewiness and more juiciness than the 89% fat control. In frozen beef patties, no significant difference was observed in beefy flavor intensity or fatty flavor intensity between the control sample and the samples with fat-replacers. Chalkiness remained relatively low for the products made with fat-replacers. A 90g beef patty made with Z-Trim fat replacer, added at 1.5% levels with 10% water, reduced fat of a comparable 89% fat patty from 10g to 6g and calories from 190 to 140, respectively (3). Gums, such as alginates, carrageenan, guar, and xanthan are also used in low fat meat formulations, often in combination with starches and proteins.

Combinations

Starch-lipid composites may work well in low fat beef formulations. A new type of composite, trademarked Fantesk^TM, prepared by passing starch-lipid mixtures through an excess-steam jet cooker creates a stable product, with lipid particles dispersed in a starch/water matrix from 1-10 micrometers in diameter. The mixture can be drum dried and milled in dry powders. When rehydrated, the powders yield an emulsion that is similar to the original cooked mixture. Because of their lipid content, logic dictated that the starch-lipid composites may make good fat-replacers, having the ability to imitate the flavor delivery and mouthfeel of full-fat products. The starches used may be of various origins such as corn, wheat, rice, and potato and the lipids may be oils or fats from either animal or vegetable sources. Proteins can also be added to the starch-lipid composites. Proteins are believed to prevent crumbling, keeping the beef patty intact. Combinations of starches, lipids, and proteins may be developed to act as effective fat replacers in low fat ground beef patties (7).

Conclusion

Although the demand is present for low-fat meat products, formulating a low-fat ground beef product equal in quality to its unadulterated, full-fat counterpart is a difficult task. Choice of ingredients is critical to developing a juicy, flavorful, low-fat product that is inexpensive to produce. Water stretches the functionality of the fat and increases yield. The key ingredient in a low-fat meat formulation is the fat replacer or combination of fat replacers chosen. They can be either protein-based, fat-based, or carbohydrate-based. Good fat replacers have a particle size and water binding capacity that mimics the mouthfeel and juiciness of real fat. They should be intrinsically bland, but have the ability to bind flavor chemicals and deliver flavor intensely to the consumer. Many formulations should be adequately tested by sensory panels. The final product should be equal to the full-fat product in all aspects, except for fat. In the end, the consumer declares the product a success or failure.

References

1.) Cooper, Kathyrn and John Michaelides. “Fat Replacers and Extenders.”

www.gftc.ca/articles/2004/fat-replacers-extenders.cfm.

2.) Wade, Marcia, ed. “Ingredient Challenges: Losing Fat, Formulating Back.”

www.preparedfoods.com/CDA/ArticleInformation/features/BNP_Features_Item/0,12

31,135765,00.html

3.) Warner, K. and G.E. Inglett. “Flavor and Texture Characteristics of Foods Containing

Z-Trim Corn and Oat Fibers as Fat and Flour Replacers.” Cereal Foods World. Oct.

97; vol. 42, issue 10, 821-825.

4.) “Whey Protein Concentrate Usage in Lowfat Meat.” Dairy Management, Inc. 1999

www.extraordinarydairy.com/archive/fs_lowfat_meat.pdf

5.) Salwa, B., S. Laroia, and P.M.T Hansen. “Flavor and Texture Characteristics of Low

Fat Ground Beef Patties Formulated with Whey Protein Concentrate.” Meat Science.

1996. Vol. 42, issue 2. 179-193.

6.) Shih, F.F. and K.W. Daigle. “Antioxidant Properties of Milled-Rice Co-Products and

Their Effects on Lipid Oxidation in Ground Beef.” J. Food Science. 2003. Vol 68,

Issue 9, 2672-2675.

7.) Warner, Eskins, Fanta, Nelsen, and Rocke. “Use of Starch-Lipid Composites in Low

Fat Ground Beef Products.” Food Technology. Feb. 2001, Vol. 55, issue 2. 36-41.

8.) Dietary Guidelines 2005, Executive Summary. www.health.gov/dietaryguidelines/dg

a2005/document/html/executivesummary.htm

9.) US Beef and Cattle Industry Stats. www.ers.usda.gov/news/bsecoverage.htm

10.) Benefits of Fiber. http://yourmedicalsource.com/library/fiber/FIB_benefits.html

Pictures-

11.) www.foodsubs.com/photos/ricebran.jpg

12.) www.bellebrook.com/images/burger_patty.jpg

13.) www.tracklements.co.uk/images/meatballs.jpg

14.) www.ccmoore.com/images/whey%20proteinconcentrate.jpg

15.) www.ars.usda.gov/is/ar/archive/feb01/fan0201.htm

16.) http://hyperphysics.phy-astr.gsu.edu/hbase/organic/carb.html

17.) www.cnn.com/health/9608/25/fat.substitute/ztrim.jpg