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对我国酱油酿造几项新技术应用之浅见 总被引:3,自引:0,他引:3
本文概述了三十年来我国酿造酱油工业开展研究的六项新技术在现阶段的投产可行性,及进一步研究方向的看法。 相似文献
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Contents of various elements in dyferent parts of the tea plant (shoot, mature leaf, small stem, thick wood and root), black tea manufactured by the crush-tear-curl and orthodox processes, and tea brew after 1 and 5 min of infusion were determined by inductively coupled plasma atomic emission spectrometry. From these, the amount of each element assimilated in the production of 1000 kg of marketable tea, as well as the quantity of each element brought into infusion and thus possib f y taken up through drinking tea, were calculated and discussed. Among the various elements assimilated by the tea plant, the shoot jraction (economically important for manufacturing commercial tea) contained high concentrations of N, P, K and Mg while the mature leaf accumulated Al, Bu, Ca, Cd, Mn, Pb and Sr. Of the dgerent elements brought into infusion while brewing black tea, the amount of K was found to be the largest (> 10000 μg g−1 tea) followed by P (700–1200 μg g−1), Mg (300–700 μg g−1), Ca and A1 (each 150–300 μg−1), Mn (60–150 μg g−1), Cu, Na, Si and Z n (each 6–50 μg g−1), B, Ba, Cr, Fe, Ni and Pb (each Id μg g−1), and Sr, Co and Gd (each <1μg g−1). The proportion of the totalamount of an element brought into infusion showed that the elements Ba, Ca, Fe and Sr were less soluble (<10 % of total amount), Al, B, Cd, Co, Cr, Cu, Mg, Mn, P, Pb, Si and Zn were moderately soluble (10–50 %), and K, Nu and Ni were highly soluble (>50%). The overall mean of the extent of solubility of all elements in 1 and 5 min showed that, out of the amount soluble in 5 min, about 68% was dissolved within 1 min. 相似文献
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研究得出葡萄酒生产时添加果胶酶、贝酵母发酵,温度28℃,明胶澄清,法国橡木桶陈酿,避光保存,所得白藜芦醇含量较高;采用高效液相色谱法测定,最佳测定条件为检测波长306nm,流动相为28%乙腈水溶液,流速为1.0mL/min,进样量为20μg,柱温25℃,测定结果的标准偏差为0.0158%~0.0212%,变异系数为5.20%~6.18%,加标回收率为99.2%~99.7%. 相似文献
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Bruno Zanoni Ella Pagliarini Claudio Peri 《Journal of the science of food and agriculture》1992,58(2):275-279
This work aims to study and model the extraction of soluble substances from coffee grounds having different particle sizes. The results demonstrate that coffee brewing cannot be considered a simple diffusion mechanism as reported in the literature. The phenomenon has two phases: a washing phase where surface soluble substances instantaneously dissolve and are transferred to the extract by a convection mechanism, and a diffusion phase involving the solubles within the porous particles. A model was set up to calculate extraction yield as the addition of the two phases. It was also demonstrated that the effect of washing shows a linear correlation with the external surface area of particles and that the composition of the extracts does not depend on extraction time. 相似文献
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目的:通过复配改善膨化玉米粉的风味及冲调性。方法:采用D-最优混料设计,向膨化玉米粉中加入不同比例的膨化小米粉、炒制红米粉、膨化大米粉和膨化黑米粉,从冲调结块率、黏度、感官评分、挥发性风味物质变化等角度对复合粉进行分析评价,并利用气相质谱技术分析不同样品的香味成分。结果:复合粉的配方为膨化玉米粉50.8%、膨化小米粉8.8%、炒制红米粉0.5%、膨化大米粉19.9%、膨化黑米粉20.0%。较单一膨化玉米粉而言,复合粉结块率降低为0.52%、黏度升高为2 880 mPa·s,感官评分87.84分,冲调性能得到极大的改善。复配后的膨化玉米粉具有青香和更浓的坚果香,风味物质增多,其中醛类物质增加最为明显。结论:复配后的膨化玉米粉冲调品质得到改善,挥发性风味物质增加。 相似文献
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Natarajan Manikandan Subbiah Seenivasan Muthukumar Navaneetha Krishna Ganapathy Narayanan Nair Muraleedharan Rajagopal Selvasundaram 《Food chemistry》2009
Tea is the most commonly consumed beverage in the world. It is prepared after infusing processed black tea in hot water. During the process of brewing, along with flavour and aroma, the residues of plant protection chemicals may also be transferred into the tea brew or infusion. The leaching of certain pesticides, such as ethion, endosulfan, dicofol, chlorpyrifos, deltamethrin, hexaconazole, fenpropathrin, propargite, quinalphos and lambdacyhalothrin from powdered black tea into the brew was studied. The rate of transfer of the pesticide residue from black tea to the hot brew was largely influenced by physicochemical parameters, such as water solubility and octanol-water partition coefficient. Tea brews prepared from untreated black tea samples were fortified with standard solutions of the respective pesticides, extracted and analysed using GC and HPLC by following standardised methods. Results revealed that the rate of leaching of residues of these pesticides into the tea brew was low due to their low solubilities in aqueous medium and high octanol-water partitioning coefficients. 相似文献
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以亚洲咖啡豆为研究对象,分别选取浅、中、深3 种烘焙度的中国云南和印度尼西亚苏门答腊产的卡蒂姆种咖啡豆,比较分析冷萃与热萃方式对萃取浓度、萃取率、可滴定酸、总酚、总糖、咖啡因、葫芦巴碱、绿原酸、抗氧化活性与挥发性成分的差异,并进行主成分分析,从而探究烘焙度对冷萃咖啡理化指标与风味成分的影响规律。结果表明,随着烘焙度增加,冷萃咖啡的萃取浓度、萃取率均显著上升,可滴定酸、总酚、葫芦巴碱、绿原酸、抗氧化活性均显著下降(P<0.05)。冷萃咖啡较热萃咖啡拥有更高的萃取浓度、萃取率与总糖含量(P<0.05),而可滴定酸、总酚含量、抗氧化活性较热萃显著偏低(P<0.05)。经顶空固相微萃取-气相色谱-质谱检测分析发现,浅烘咖啡豆萃取液中的挥发性成分含量显著低于烘焙度高的咖啡萃取液,深烘咖啡豆萃取液中挥发性成分种类与总含量最多。进一步通过主成分分析能较好区分冷萃和热萃咖啡,两者挥发性成分贡献率具有较大差异。2-丁酮、2-丁烯醛等花香类物质对浅烘冷萃咖啡贡献率更高,而2-甲基吡嗪、糠醇等呈现烘焙坚果类香气物质对浅烘热萃咖啡贡献率更高;2,6-二乙基吡嗪、川芎嗪等烘焙坚果类香气物质对中烘冷萃和热萃咖啡具有较高的贡献率;2-乙烯基呋喃、甲基糠硫醇、2,5-二乙基吡嗪、糠基甲基硫醚等物质对深烘冷萃咖啡有较高贡献率,二甲基二硫、对甲酚、1-甲基吡咯等物质对深烘热萃咖啡贡献率更高。相对于热萃咖啡,烘焙度对冷萃咖啡抗氧化能力与挥发性成分的影响更大。 相似文献