PCR and DHPLC methods used to detect juice ingredient from 7 fruits

To provide accurate and fast method for labeling regulation on fruit juice, conventional PCR, real-time PCR and DHPLC techniques were explored in this study to detect ingredient from 7 fruit species. ITS1-5.8S-ITS2, TrnL-TrnF from chloroplast genome and thaumatin-like protein gene from nucleus genome were targeted. Sensitivity of 6 primer (probe) pairs was determined to be 1–10 pg DNA. Orange and mandarin were universally amplified by the same primer pair and the 8 bp divergence of PCR products could be differentiated by DHPLC analysis. 30 Fruit samples collected from local market were tested and no mislabeling was discovered