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本实验尝试从马铃薯中提取蛋白质等成份,并适当添加姜汁,制成一种新型饮料,对饮料生产的工艺条件作了详细探讨,成功地解决了马铃薯褐变及沉淀等问题,确定了最佳配方及工艺。 相似文献
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酶法提取树莓汁的研究 总被引:8,自引:1,他引:7
本试验以澳洲红、早红、美国22三个品种树莓为原料,通过不同的酶处理方法来制原果汁,优选适于制汁的品种和酶处理方法。 相似文献
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Grard J Martin Doubou Danho Claude Vallet 《Journal of the science of food and agriculture》1991,56(4):419-434
More than 500 carbohydrate samples have been characterised by hydrogen, carbon and oxygen isotopic parameters measured on ethanol and water resulting from controlled fermentation. Different chemical states of the carbohydrate pool have been considered: polysaccharides from cereals, tubers and leguminosae (maize, sorghum, rice, wheat, barley, potato, bean), glucose, fructose and sucrose from fruits (pineapple, citrus, apple, soft fruits), sucrose from sugar plants (beet, cane). The overall carbon-13 content of ethanol and the deuterium and oxygen-18 contents of water before fermentation were determined by mass spectrometry of isotope ratios whereas the investigation of site-specific natural isotope fractionation by deuterium NMR has provided access to the deuterium contents in the methyl (I) and methylene (II) sites of ethanol. The results have been analysed in the multidimensional space of these isotopic variables. Hierarchical clustering, principal component and discriminant analyses have been performed. Among fruits, for example, the pineapple group exhibits a 100% discrimination with respect to the apple and citrus groups which are themselves well distinguished. A still higher discrimination is reached between the three groups, citrus, cane and beet, and the addition of 10% exogenous cane or beet sucrose to citrus juice is unambiguously detected. 相似文献
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Alfalfa juice was extracted from plants during the graving phases of the first and second crops. The alfalfa juice was dried and solute concentrations were measured periodically during the process using freezing point depression (FPD) as an indicator. Solute/solvent weight ratios were calculated from the freezing point depression of fresh unconcentrated 'uice extracted from both firsc and second crops. At the time of harvest, tie FPD was a function of this ratio. The first and second crops behaved distinctively different during the drying process, with the second having a larger soluce concentration and a greater FPD at a given moisture content. The appearance of preci itate during the drying process and the general1 large FPD makes this materiay a questionable product for drying vitg low temperature processes. 相似文献
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One of the major problems in spray drying of fruit juices such as lime juice is stickiness and thermoplasticity of their compositions. Lime juice consists of invert sugars and citric acid, which have low glass transition temperatures. Due to this characteristic, the particles stick on the dryer wall upon their collision with it. As a result, drying of these materials is very difficult. In order to solve this problem, various percent of silicon dioxide and maltodextrin (DE5), based on total soluble solid content of lime juice, have been used to reach a suitable drying condition. A cool chamber wall spray dryer was used in this investigation in order to decrease the probability of particles stickiness on the wall. Our investigation revealed that an addition of 10% silicon dioxide and 20% maltodextrin (DE5) to lime juice is the optimum amount for a complete and successful drying of lime juice. Sampling of particles from different longitudinal distances in the dryer tower is carried out to find the particle moisture contents as they fly downward in the dryer. The results show a very fast decrease in entrance moisture contents. Based on our experimental data, the variation of moisture contents are presented as a function of radial distance from central line and longitudinal distance from the entrance region. 相似文献
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为了改善苹果酒生产中酸度低、单宁少的缺陷,以红富士苹果为原料,经榨汁、护色、海红果汁调整成分、发酵、澄清等工艺生产苹果酒,并与柠檬酸调整苹果汁成分的发酵进行对比,得出海红果汁调节苹果汁酸度酿造苹果酒优于传统的柠檬酸调酸,其优化工艺条件为:初始pH3.6,初始糖度24°Brix,发酵温度20℃,酵母接种量为0.3‰,在此条件下所得苹果酒金黄色,果香酒香协调浓郁,酒体复杂丰满. 相似文献
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本文研究了聚丙烯酰胺澄清苹果汁时的主要成分变化。结果表明:澄清后果汁的透光率在98%以上;主要果汁成分的保存率均在95%以上。这一结果与果胶酶澄清法和超滤澄清法有所不同。这种差异是由于澄清机理不同所致。 相似文献
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开发管式膜,用于苹果汁在线澄清处理,结果显示,国产管式膜分离性能优良,膜通量保持稳定,且定时清洗可以恢复膜通量,能满足实际生产要求。 相似文献