Yan Yin¹, Lu-juan Xing¹, Guang-hong Zhou¹, Wan-gang Zhang^1,

The effects of different amounts of rosemary extract (RE) on total bacterial counts, lipid and protein oxidation, pH, color, textural attributes, cooking yield and sensory attributes of raw ground pork patties during 10 d of chilled storage were assessed. The contents of carnosic acid, carnosol and rosmarinic acid in RE used in the current study were 53, 33 and 55 g kg^-1 respectively. Patties containing RE exhibited significantly lower lipid oxidation compared to control samples during chilled storage (P < 0.05). Both protein oxidation and total bacterial counts were reduced by RE at 4, 7 and 10 d of storage (P < 0.05). Compared to control, patties containing RE had higher hardness, resilience and chewiness values and samples with the addition of 0.2 g kg^-1 RE had higher a* values at 4 and 7 d of storage (P < 0.05). Patties blended with 0.2 g kg^-1 and 0.3 g kg^-1 RE displayed lower pH values during chilled storage and higher cooking yield at 4 and 7 d of storage (P < 0.05). No significant differences were detected for the sensory attributes (P > 0.05). The results indicate that RE had significant antioxidative and antibacterial properties when added to raw ground pork patties. Supplementation with RE improved the physicochemical qualities of pork patties without deteriorating the sensory qualities.

rosemary extract, raw ground pork patties, lipid oxidation, protein oxidation, antibacterial activity, antioxidative activity