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To ascertain the role of natural fermentation and its associated microorganisms in the eating quality of fermented rice noodles, we compared changes in main chemical components, microorganisms, and eating qualities of fermented rice noodles compared with unfermented ones. The results indicated that noodles made from rice grains fermented at 40°C have higher tensile strength, hardness, springiness, and chewiness. Statistical analyses show that fermentation significantly changed the content and composition of the starch, lipid, protein, amylose, and ash of the indica rice. High-throughput sequencing analyses of the supernatant of the fermentation samples revealed the dynamic changes of the bacteria population during fermentation. Lactic acid bacteria are found to be the dominant bacteria (more than 90%) during the entire process. The relatively high abundance of Lactobacillus fermentum and L. delbrueckii at each phase of the fermentation suggests that the two species are likely to be the species that determ...

The pasting properties of rice flours and reconstituted rice flours from mixing a common starch with proteins extracted from different rice cultivars at different total protein content levels were studied. Results showed that not only the total protein content but also the protein composition had an effect on the pasting properties of the rice flours. Among the different strands of rice proteins, globulin had the strongest influence on the pasting properties, followed by glutelin, whereas prolamin had the least influence. At the subunit level of the proteins, proteins with a molecular weight of 17,000, most likely from globulin, had the strongest effect on the peak viscosity of the rice flour, followed by those of 33,000. In comparison with that of the rice starch, the influence of proteins in rice was limited. The effect of interactions between the rice proteins and the starch, such as the role of starch-granule-associated proteins, was not isolated in this study, and further investigation is re...

Response surface methodology (RSM) was used to study the effect of enzyme to substrate ratio (11.8–23.6 U α-amylase/g rice starch), hydrolysis temperature (90–100°C) and pH value (6.0–6.6) on the gel strength of rice starches-based fat substitute using α-amylase hydrolysis. The optimum conditions obtained from response surface analysis was 16.52 U/g enzyme dosage, 92°C hydrolysis temperature while the influence of pH was found insignificant in the range tested. Under these optimum conditions, the gel strength of this fat substitute was 113 g/cm2, very close to the gel strength of butter of 114 g/cm2, while the solubility of the substitute was 1.33 ± 0.01% and the swelling power 4.85 ± 0.02. There were no observable differences in the granular size distribution between the untreated rice starch and the hydrolyzed rice starch. Rheological properties of this rice starch-based fat substitute implied that it is easier for the substitute to form three-dimensional networks under 34°C.

The orthorhombic Pmnb polymorph of the title compound is prepared without significant impurities by solid state reaction of stoichiometric quantities of LiOH, MnCO3, and SiO2 together with 20 mol% adipic acid (1.

Drop-based crystallization techniques are used to achieve a high degree of control over crystallization conditions in order to grow high-quality protein crystals for X-ray diffraction or to produce organic crystals with well-controlled size distributions. Simultaneous crystal growth and stochastic nucleation makes it difficult to predict the number and size of crystals that will be produced in a drop-based crystallization process. A mathematical model of crystallization in drops is developed using a Monte Carlo method. The model incorporates key phenomena in drop-based crystallization, including stochastic primary nucleation and growth rate dispersion (GRD) and can predict distributions of the number of crystals per drop and full crystal size distributions (CSD). Key dimensionless parameters are identified to quickly screen for crystallization conditions that are expected to yield a high fraction of drops containing one crystal and a narrow CSD. Using literature correlations for the solubilities, growth, and nucleation rates of lactose and lysozyme, the model is able to predict the experimentally observed crystallization behavior over a wide range of conditions. Model-based strategies for use in the design and optimization of a drop-based crystallization process for producing crystals of well-controlled CSD are identified.