Abstract

Thigh muscles were obtained from a batch of 120 broiler chickens fed diets containing 0, 1.5, 3.0, 4.5 and 6.0% dried Hibiscus sabdariffa calyces (diets A, B, C, D and E respectively). The thigh muscles were studied as uncooked and steam-cooked, and refrigerated for up to 9 days. Oxidative stability of muscle was measured using the thiobarbituric acid test and bacteria isolates were identified and quantified. Moisture and lipid contents of muscle were not affected (P>0.05) by dietary treatments. Oxidation of refrigerated meat decreased (P<0.01) with increasing levels of dietary H. sabdariffacalyces. Uncooked meat contained more bacteria load than cooked meat (P<0.001). With increasing levels of dietary H. sabdariffa calyces and length of refrigeration, bacteria load of meat decreased. Six types of bacteria (Staphylococus aureus,Bacillus subtilis, Corynebacterium sp., Escherichia coli, Salomnella sp. andLactobacillus salivarius) were isolated from the fresh-uncooked meat but only three (S. aureus, B. subtilis and Corynebacterium sp.) from the cooked meat. Bacteria type isolated decreased after 9 days of refrigeration. It was concluded that H. sabdariffacalyces contain potential antioxidant and antibacterial agents that need further investigation.

Key words: Oxidative and bacteria deterioration, Hibiscus sabdariffa calyces, broiler chicken meat.