Abstract: In this study nisin was used in the preservation of refrigerated beef :This paper had two sections the first section was mainly to find out the effective preservative concentration ,throuth on factor experiment-designing 5 preservative solutions with different concentrations dipping each beef group into different solutions. then vacum packaging storing at 2 ±2℃ In the second section .by applying four factors quadratic rotating design. the reciprocity between nisin and calcium propionate .sodium lactate or postassium sorbate was studied. The major results of the study were 1 )Nisin had significant oil beef preservation .The higher the concentration the better the efficaes of the preservation Through statistic analysis the results suggested that the optimal concentration of nisin was 75ppm. 2)By applying four factors quadratic rotating design. we found that nisin had synergistic effect with sodium lactate but counteraction with potassium sorbate.

Key words: Nisin, Refrigerated beef, Preservation, Reciprocity