保健食品菌落总数测定中国标方法与培养基稀释法的比较研究

Comparison of GB method and medium dilution method in aerobic plate count (APC) determination in health food

目的分别用国标方法与培养基稀释法对保健食品菌落总数进行测定,并对结果进行比较,选出更适合保健食品菌落总数测定的方法。方法对7批本身存在微生物并且含一种或多种抑菌成分的保健食品,分别采用国标方法和培养基稀释法进行菌落总数的测定,并对结果进行比较。结果国标方法测定结果中,出现了稀释级之间不成10倍关系的情况,这是由于保健食品中含有的抑菌成分使微生物的生长受到了抑制,从而使计数结果不准确。国标方法测定结果低于培养基稀释法测定结果。结论在采用国标方法对保健食品进行菌落总数测定时,如果出现稀释级之间的菌落数不成10倍关系的情况,建议采用培养基稀释法进行测定,并将培养基稀释法结果作为最终结果。

Objective To determine aerobic plate count（APC） in health food by GB method and medium dilution method respectively,and compare the detection results to select a better determination method of aerobic plate count in health food.Methods Seven batches of health foods containing their own microorganisms and one or more antibacterial ingredients were collected for aerobic plate count using GB method and medium dilution method,respectively,and the results were compared.Results The ratio of aerobic plate count between dilution levels had large difference with the theoretical value（10） when using GB method,because the growth of microorganism was inhibited by antibacterial ingredients contained in health food,making the inaccurate count.The counting of GB method was lower than that of medium dilution method.Conclusion It is suggested to use medium dilution method for aerobic plate count in health food when the ratio of aerobic plate count between dilution levels was not close to 10（the theoretical ratio） by GB method,and the result of medium dilution method was regarded as the final result.