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Abstract: A useful procedure for the qualitative determination of edible vegetable oils adulteration has been developed. A CE-SSCP (Capillary Electrophoresis-Single Strand Conformation Polymorphism) method based on PCR (Polymerase-Chain-Reaction) technology was established to distinguish olive, soybean, sunflower, peanut, sesame, maize and corresponding edible oils, which are the most common edible oils in China. Two rbcL (ribulose 1,5-bisphosphate carboxylase large subunit) gene fragments were amplified from these 6 oil plants by 2 pairs of universal primers (uni4 and rbcl1) respectively and the amplicons were identified by CE-SSCP on ABI 3100 automatic sequence analyzer. Six oil plants were successfully differentiated by combined pattern of uni4 and rbcl1. Sensitivity of the method detecting DNA and oil mixture at different ratio was at level as low as 10% (V/V). The method developed was very suitable for the determination of modeled adulterants but it may also reveal an adulteration even if it does not derive from the adulterants employed in this study. [Copyright &y& Elsevier]

Chinese steamed bread (CSB) is one of the traditional staple foods of Chinese people, and its quality is mainly affected by wheat gluten and starch. Herein, four different ratios of wheat gluten and starch were selected to investigate its effects on the properties of CSB. It was observed that the surface of CSB gradually became darker, yellower, and shrank with increasing gluten-starch ratio. The hardness and chewiness of CSB decreased with the increasing of gluten-starch ratio, as well as the network structure of CSB was dense and porous. The increase of gluten content could effectively control the migration of water in the CSB. Moreover, with increasing gluten-starch ratio, the crystallinity of starch was reduced from 9.95% to 2.03%. As a result, the ratio of gluten-starch mainly affected the development of gluten network structure and starch gelatinization through the competition of water between gluten and starch in the system, which in turn affected the quality of CSB. Thus, it will provide the basis for the adaptability of wheat flour from different origins as the raw material of CSB processing, and also provide guidance for consumers to select flour with different gluten protein content to prepare steamed bread according to their preferences., (Copyright © 2020 Elsevier B.V. All rights reserved.)