Corn starch changes during tortilla and tortilla chip processing.

Objective: The present study aimed to investigate effect of addition date seed powder on the chemical composition, rheological properties, diffraction scanning colorimetric, x-ray diffraction, infra-red (IR), flavonoid, antioxidant activity, total phenolic compounds and sensory evaluation of snack from them. Methodology: Raw materials (oat and date seed flour) and snacks were analyzed for their proximate composition, rheological (rapid viscoanalyzer and following number), physical properties, color and texture were subjected to measurements using Differential Scanning Calorimetery (DSC). Each sample was tested for its color, flavor, taste, crispness, appearance and overall acceptability. Results: The obtained results revealed that, incorporation of date seed powder resulted in a significant increase in fibre and ash contents and in a decrease in protein content. Increasing DS levels in snacks led to increase the falling

Sugar uptake by the solventogenic clostridia

The acetone–butanol–ethanol fermentation of solventogenic clostridia was operated as a successful, worldwide industrial process during the first half of the twentieth century, but went into decline for economic reasons. The recent resurgence in interest in the fermentation has been due principally to the recognised potential of butanol as a biofuel, and development of reliable molecular tools has encouraged realistic prospects of bacterial strains being engineered to optimise fermentation performance. In order to minimise costs, emphasis is being placed on waste feedstock streams containing a range of fermentable carbohydrates. It is therefore important to develop a detailed understanding of the mechanisms of carbohydrate uptake so that effective engineering strategies can be identified. This review surveys present knowledge of sugar uptake and its control in solventogenic clostridia. The major mechanism of sugar uptake is the PEP-dependent phosphotransferase system (PTS), which both transports and phosphorylates its sugar substrates and plays a central role in metabolic regulation. Clostridial genome sequences have indicated the presence of numerous phosphotransferase systems for uptake of hexose sugars, hexose derivatives and disaccharides. On the other hand, uptake of sugars such as pentoses occurs via non-PTS mechanisms. Progress in characterization of clostridial sugar transporters and manipulation of control mechanisms to optimise sugar fermentation is described