Indirect detecting bacillus spores in skim milk by ultraviolet photometric method

Based on the liner relationship between the spore concentration and the content of dipicolinic acid (DPA), a special component found in spores, a special component found in spores, a rapid method has been developed for the indirect determiantion of spores in skim milk. The dipicolinic acid released from bacterial spores in skim milk was determined by using ultraviolet photometry. The detection accuracy and recovery of DPA were also studied. Good correlation was obtained between the counts of spores and the content of DPA. The regression equation is y=0.2084x-0.9363, R2=0.6998. The validate test (P < 0.05) shows that the method can be applied to forecast the counts of spores in skim-milk effectively.