Antioxidant Properties of Lotus Leaf (Nelumbo nucifera) Powder and Barley Leaf (Hordeum vulgare) Powder in Raw Minced Pork during Chilled Storage

The effects of additions of lotus leaf (0.1 and 0.5%) and barley leaf powder (0.1 and 0.5%) on the lipid oxidation and microbiological analysis of raw minced pork were investigated after 1, 4, 7, and 10 d at chilled storage. Days of storage caused (p<0.05) decreases in pH values in samples with lotus leaf (LP) and barley leaf powder (BP). L * and a * values decreased, and b * values increased in the treatments with increasing lotus leaf and barley leaf powder contents, respectively. The decrease in a * values was lowest (p<0.05) in the treatment with 0.1 % BP. Thiobarbituric acid reaction substance values and free fatty acids in 0.5 % LP were lowest (p<0.05) on day 10. Thus, the addition of lotus leaf powder significantly improved lipid oxidative stability in the raw minced pork during chilled storage of 10 d. Furthermore, the raw minced pork treatments with LP and BP presented low peroxide values and total microbes as compared to control (-) (without LP and BP). These results indicate that LP and BP can be incorporated into raw minced pork as natural additives to retard oxidation. Key words: lotus leaf, barley leaf, lipid oxidation, microbiological analysis, minced por