Method for detecting amount of coliform in food by utilizing digital PCR (polymerase chain reaction)

The invention discloses a method for detecting the amount of coliform in food by utilizing a digital PCR (polymerase chain reaction). The method comprises steps as follows: 1), bacteria in to-be-detected food are enriched, enrichment and DNA (deoxyribonucleic acid) conjugate are jointly incubated, a PCR amplification template is obtained, and the DNA conjugate is a substance which cannot penetrate through a complete cell membrane, but can be combined with DNA exposed after the cell membrane is damaged; 2), a PCR system is prepared for digital PCR and contains the PCR amplification template, a universal primer pair for coliform, fluorescent dye, dNTP (deoxyribonucleoside triphosphate) and DNA polymerase; and 3), the amount of coliform in the to-be-detected food is calculated according to a fluorescence signal generated through the reaction. According to the method, bacteria in the food are not required to be subjected to isolated culture, and the detection time is as short as 3-4 hours; simultaneously, interference of background DNA and matrixes is reduced, and the sensitivity is decreased to one copy; and according to the method, a standard curve is not required to be set, the amount of coliform in a sample can be directly intercepted according to a result, and the operation step is simplified greatly.