Hydrolysis of starches and flours by sorghum malt amylases for dextrins production

The biochemical changes in legumes during high-temperature micronization

The article considers the change in chemical and biological characteristics in some legumes grains, under conditions of high-temperature micronization with different moisture contents during heat treatment with infrared rays. The heat treatment of grains was carried out on a laboratory apparatus with a quartz radiant infrared panel. The temperature variation in the heat treatment zone occurred due to changing the distance between the panel and the surface of grains. The grain temperature was determined using a laser thermometer, and with a timer. To determine chemical and biological characteristics, we used a special optical density metering device. We have studied: 1. The dependence of starch content on the temperature in the changing initial moisture content. We found that after 30 seconds of high-temperature micronization of, “Tsanava“ beans at a grain moisture content of 12.7%, the starch content in the grain increases from 39.65% to 40.12%, then gradually decreases, and at 18.3% moisture content, it increases from 38.71% to 41.2%, with a moisture content of 28.6% it increases from 37.36% to 42.42%. Similar processes are also observed for the beans “field red“ and “white lupine“; 2. The dependence of glucose content on the temperature in the changing initial moisture content. As the mass fraction of starch decreases, the percentage of sugar (in terms of the equivalent amount of glucose) at a moisture content of 12.7% at the initial stage increases from 1.36% to 1.46%, and then the percentage of sugar increases relatively quickly to 1.64%, at a moisture content of 18.3% it increases from 1.3% to 1.38%, and then increases to 1.51, with a moisture content of 28.6%, it increases from 1.28% to 1.35% and then increases to 1.54. Similar processes are also observed for the beans “field red“ and “white lupine“.

A Comparative Analysis of Methods for Quantitation of Sugars during the Corn-to-Ethanol Fermentation Process

The quantitation of sugars, including glucose, the primary fermentable sugar; maltose (DP2); and maltotriose (DP3), is a standard procedure during the corn-to-ethanol fermentation process. The quantitation of glucose by the Megazyme Assay utilizing glucose oxidase and peroxidase enzymes (GOPOD) and UV-Vis detection, high-performance liquid chromatography with refractive index detection (HPLC-RID), and liquid chromatography mass spectrometry (LC-MS) with electrospray ionization (ESI) and selected ion monitoring (SIM) was studied. Three biological flask fermentation replicates were analyzed every 12 h beginning at 14 h of fermentation (T14) until near completion of fermentation (T62).The method comparison results for glucose quantitation showed that the LC-MS SIM analysis had the lowest limit of quantitation (LOQ) at 2 ppm and the widest dynamic range of 2.7 orders of magnitude. The HPLC-RID analysis had a linear dynamic range (LDR) of 1.5 orders of magnitude with an LOQ of 1500 ppm. The Megazyme GOPOD analysis had an LDR of 0.9 orders of magnitude with an LOQ of 120 ppm.The HPLC-RID method was ideal for glucose quantitation when it was present in high concentrations. In contrast, maltose and maltotriose components were found to be present in lower concentrations, such that simultaneous quantitation of the three analytes is difficult during fermentation. The LC-MS method was the only method able to quantify the concentration of glucose successfully and simultaneously with DP2 and DP3 in all the fermentation broth samples collected from T14 through T62 during the corn-to-ethanol fermentation process.

Enzymatic Synthesis and Structural Characterization of Theanderose through Transfructosylation Reaction Catalyzed by Levansucrase from Bacillus subtilis CECT 39

This work addresses the high-yield and fast enzymatic production of theanderose, a naturally occurring carbohydrate, also known as isomaltosucrose, whose chemical structure determined by NMR is α-d-glucopyranosyl-(1 → 6)-α-d-glucopyranosyl-(1 → 2)-β-d-fructofuranose. The ability of isomaltose to act as an acceptor in the Bacillus subtilis CECT 39 levansucrase-catalyzed transfructosylation reaction to efficiently produce theanderose in the presence of sucrose as a donor is described by using four different sucrose:isomaltose concentration ratios. The maximum theanderose concentration ranged from 122.4 to 130.4 g L^-1, was obtained after only 1 h and at a moderate temperature (37 °C), leading to high productivity (109.7-130.4 g L^-1h^-1) and yield (up to 37.3%) values. The enzymatic synthesis was highly regiospecific, since no other detectable acceptor reaction products were formed. The development of efficient and cost-effective procedures for the biosynthesis of unexplored but appealing oligosaccharides as potential sweeteners, such as theanderose, could help to expand its potential applications which are currently limited by their low availability.

Quantification of sugars in wheat flours with an HPAEC-PAD method

An HPAEC-PAD method has been developed and validated for the simultaneous determination and quantification of six sugars (glucose, isomaltose, maltose, maltotriose, maltotetraose and maltopentaose) in wheat flours, by extraction with water and precipitation of proteins with Carrez II. Analyses were carried out on a Hamilton RCX-30 column with a gradient elution of NaOH 50mM (A) and NaOH 50mM+NaAcO 500 mM (B). Total run time was 38 min. Detector conditions were as follows: E1, +100 mV; E2, +550 mV; E3, -100 mV. The method was validated, with LODs ranging between 0.03-0.21 mg L(-1) and LOQs between 0.10-0.71 mg L(-1), R(2) between 0.9941 and 0.9983; recoveries were from 74.16% to 110.86% and RSDs for intraday repeatability, interday repeatability and reproducibility between 0.35-8.34%, 2.34-6.64% and 1.90-5.68%, respectively. The method was successfully applied to quantification of these sugars in wheat flours.