Healthier functional beef burgers

Abstract

Beef burgers were traditionally associated with nutrients and nutritional profiles that are often considered negative including high levels of saturated fatty acids, cholesterol, sodium, and high fat and caloric content. However, meat is a major source for many bioactive compounds including iron, zinc, conjugated linoleic acid, and B vitamins. By selection of lean meat cuts, removal of adipose fat, including oils of vegetal or marine origin (with high content of polyunsaturated fatty acids), and addition of phytosterols, this type of products could become into healthier functional foods. To obtain a product with similar characteristics to the ?classical? beef burgers emulsifiers or binding agents are needed, as well as antioxidants to control lipid oxidation. Low-fat beef burgers with high oleic sunflower, deodorized fish oil, and phytosterols were formulated including whey proteins or egg white and natural antioxidants (tocopherols and/or oregano-rosemary extract). Products were characterized and the effect of frozen storage at -20ªC on the quality of the cooked hamburgers was studied. Cooking yield, moisture and lipid retention, press juiciness, texture profile analysis, microstructure, oxidative stability, color, fatty acid profile, phytosterols contents, microbiological counts, and sensory acceptation were determined. Cooking yields ranged between 79.4 and 84.5 % for all the formulations, and became slightly lower with frozen storage. Press juiciness also diminished with storage time while hardness increased, for both emulsifiers used. Lipid retention was higher than 95 % while water retention was higher than 70 %, for whey proteins or egg white and these parameters did not change during frozen storage. Whey proteins protected better from oxidation than egg white, and tocopherols demonstrated an adequate antioxidant effect in formulations with egg white. For all the formulations unsaturated/saturated fatty acids ratio was higher than 5.8, showing a good lipid balance in the products. Global acceptability for all the formulations presented sensory scores higher than 7 (in a 1 to 9 scale). More than 82.3 % of the panelists liked the taste of the products, 78.7 % liked the texture, and over 86.8 % of the panelists liked the products, considering the overall acceptability of the burgers. These results showed that the presence of the high oleic sunflower and deodorized fish oil did not adversely affect the low-fat beef burgers. The consumption of 100 g of the cooked product would provide 6% of the recommended daily intake of phytosterols to decrease cholesterol and heart disease risk.