Qualitative and quantitative detection of adzuki bean ingredient in rice bean processed foods

Abstract

ObjectiveIn order to achieve the authenticity and quality identification of rice bean processed food, qualitative real-time fluorescent polymerase chain reaction (PCR) and quantitive droplet digital PCR (ddPCR) methods were established for adzuki bean ingredients misused or mixed in rice bean processed food.MethodsSpecific primers and probes for qualitative real-time fluorescent PCR were designed according to their conserved sequences in genomic DNA, as well as universal primers and probe for quantification of adzuki bean ingredient in rice bean processed foods using duplex droplet digital PCR. Then a linear formula of mass ratio-DNA copy was established.ResultsThe LODs of real-time fluorescent PCR for rice bean and adzuki bean were 0.1 and 0.01ng/μL separately, and the LOQs of ddPCR for both were 6 copies/μL. Accurate quantification of adzuki bean ingredient with a mass ratio from 5% to 80% in rice bean processed foods therefore could be achieved.ConclusionThis method could be used for qualitative and mass ratio quantification determination of adzuki bean ingredients in rice bean processed food.

Keywords

• rice bean
• adzuki bean
• real-time polymerase chain reaction
• droplet digital polymerase chain reaction
• qualitative
• quantification