جستجوی مقالات مرتبط با کلیدواژه « واکنش زنجیره ای پلیمراز زمان واقعی » در نشریات گروه « صنایع غذایی »

One of the common adulterations in milk and dairy products, is the addition of low-priced vegetable oils such as palm oil in order to increase the profitability of products. Therefore, there is an urgent need to develop accurate, fast and reliable identification techniques to protect consumers against this type of adulteration. The aim of the present study was DNA barcoding with real-time PCR as a reliable method for detecting palm oil fraud with levels of 2, 3, 4, 5, 10, 30, 50 and 100 % and positive and negative control samples in yogurt. According to the results, the highest and lowest concentrations of DNA extracted belonged to the palm oil sample of 100 % and 3% , respectively, while among all samples, the concentration of DNA extracted in sesame oil and then in the control oil sample was lower. It was determined from other samples. The lowest and highest adsorption rates (10mm) between the samples were control oil (excluding palm) and 100 % palm oil, respectively. There was no significant difference in absorption rate between 4%, 5% and sesame oil samples. The range for detecting palm oil adulteration was from 0.05% to 100% palm oil. LOQ and LOD were 0.1 % and 0.05 % of palm oil, respectively.

Detection of the residual meat or other components of pork in halal food products particularly in Muslim countries is of prime importance. In this study, real-time polymerase chain reaction based on SyberGreen dye was used for detection of pork DNA in meats and highly processed products such as pork gelatin and gelatin-containing products. SyberGreen based real-time polymerase chain reaction was designed for an assay that can detect pork DNA in meats and highly processed pork derivatives including gelatin and gelatin containing products. The proposed method uses the newly specific primers designed by AlleleID7 software that amplify a 114 bp fragment of porcine mitochondrial D-loop region. After optimization of mixture composition and thermal program for achieving maximum fluorescence and minimum threshold cycle, standard curve of serially diluted DNA extracted from pork meat showed power for detection of 0.001 diluted DNA compared with starting DNA material with the efficiency of 92%. Specificity of this method was evaluated by testing the extracted DNA from sheep, cow, chicken and fish which had no amplification for negative control samples. To analyze the method for detecting highly processed pork derivatives, several pork gelatin powders and sheets were selected and the real-time polymerase chain reaction based on SyberGreen dye proved to successfully detect the traces of the pork residues in the samples tested.