Effect of Plant Extracts on Lipid Oxidation and Changes in Nutritive Value of Protein in Frozen-Stored Meat Products

Abstract

This study investigated the effect of antioxidants on lipid stability and changes in protein nutritional value of frozen-stored meat products. The extracts from thyme, green tea, rosemary were used to enrich fried meatballs from ground pork. During 180-day storage of meat products, the lipid oxidation (peroxide and TBARS value), methionine and lysine availability and protein digestibility were periodically monitored. The results were compared with BHT. The addition of extracts limited lipid oxidation in stored meatballs. The extracts from tea were superior to the others from thyme and rosemary. Moreover, the extracts reduced changes in amino acids content, as well as protein digestibility, during storage time. The highest ability to lower the losses in the nutritional value of proteins was demonstrated for rosemary extract. These results indicate that plant extracts can be utilized to prolong shelf-life of the products by protecting them against lipid oxidation and deterioration of their nutritional quality. Practical Applications Nutritional and health aspects shed new light on the use of antioxidants in food technology and give rise to a broad-based introduction into nutritional practice of new foods rich in (or enriched with) natural antioxidants. Further research is required in order to understand the composition and content of these compounds in plant foods and to recommend the introduction of polyphenol-rich products of high antioxidant activity in human diet. These products may constitute an important group of health-oriented food products, which are additionally characterized by high stability.