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Victor Falguera Jorge Fernando Vélez‐Ruiz Verónica Alins Albert Ibarz 《International Journal of Food Science & Technology》2010,45(10):2194-2200
Several rheological properties of concentrated mandarin juice were investigated, quantifying thixotropic behaviour and fitting experimental data to the Hahn, Weltman, and Figoni–Shoemaker equations. The latter one proved best for modelling the time dependency response. Pseudoplastic behaviour fitted well with the Herschel–Bulkley model in the interval between ?12 and 6 °C, in which yield stress and the flow behaviour index scarcely changed with temperature. The consistency coefficient and apparent viscosity both decreased as temperature increased. Fitting these consistency data to the Arrhenius‐type equation, a value of 33 kJ mol?1 for activation energy was obtained. Concentrated mandarin juice displayed viscoelastic properties in the temperature range between ?12 and 6 °C, with the elastic character (determined by the juice’s pectin content) predominating over the viscous nature at low frequency values, but with this behaviour being inverted for high values. Furthermore, as the temperature became higher, the elastic character became more important than the viscous nature. 相似文献
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银杏叶菠萝汁保健饮料的制作 总被引:1,自引:0,他引:1
主要介绍了银杏叶中有效成分黄酮类化合物的提取方法及将其添加到菠萝澄清汁中,配制成保健饮料的工艺操作过程。采用醇-水溶液提取法提取银杏叶有效成分,提取率高。长期饮用该产品可以有效地预防冠心病、心绞痛、高血压等脑血管疾病。 相似文献
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对比不同澄清剂对菠萝汁的澄清效果。选择单宁与明胶复合澄清剂进行单因素分析和正交实验。结果表明,单宁和明胶复合澄清剂澄清菠萝汁的主要因素为温度,其次为添加量、单宁∶明胶质量比和p H;菠萝汁澄清的最佳工艺条件为加热温度55℃,单宁∶明胶(质量比)1∶2,添加量0.09 g/100 m L,p H3.0。在此条件下,得到澄清后菠萝汁的透光率为94.8%,所得的菠萝汁澄清透明,色泽自然。 相似文献
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Marta Dizy Pedro Jesus Martín-Alvarez María Dolores Cabezudo M. Carmen Polo 《Journal of the science of food and agriculture》1992,60(1):47-53
Several multivariate statistical methods (principal component, cluster, stepwise discriminant and multiple linear regression analysis) were applied to analytical data obtained by conventional methods and to analytical data for free amino acids, in an attempt to distinguish between grape, apple and pineapple juice. Analysis for methionine, proline, asparagine, arginine and glutamic acid made it possible to differentiate among the 34 samples of grape, apple and pineapple juices studied. Multiple linear regression analysis of computer-simulated mixtures of grape and apple juices made it possible to detect the proportion of each fruit within the blend. 相似文献
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蓝莓浓缩汁流变特性及化学组成的变化 总被引:1,自引:0,他引:1
流体的流变学可为工艺设计提供有关数据,并有助于找出产品组成及加工工艺对流变性质的影响。本研究采用AR1000型流变仪研究了浓缩蓝莓汁(60°Brix)在(20~60℃)范围内的流变特性。通过回归分析发现,在研究的温度和浓度范围内,浓缩蓝莓汁表现为牛顿型流体,温度对粘度的影响可用阿雷尼乌斯(Arrhenius)方程来表示,浓度对粘度的影响可用指数方程来表示。推导出了温度和浓度对浓缩蓝莓汁粘度综合影响的方程式并比较了浓缩前后蓝莓汁化学组成的变化。 相似文献
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用正交试验探讨了菠萝醇化果汁生产中酒基、醇糖比、勾兑方式等因素对菠萝醇化果汁的典型香气和滋味的影响,从而确立了醇化菠萝果汁生产的适宜工艺条件. 相似文献
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以浊度、色差和透光率为指标,壳聚糖和黄原胶为澄清剂,研究了壳聚糖/黄原胶对菠萝汁的澄清效果,确定了最佳的工艺参数,并在单因素实验的基础上,通过正交实验,得出澄清菠萝汁的最适工艺为:温度35℃,时间70min,壳聚糖(10g/L)与黄原胶(10g/L)的比例1∶1,果汁pH3.4,验证实验结果表明,此时浊度为0.93NTU,透光率高达98.5%,菠萝汁的色差b*=14.47,在此工艺条件不但能得到满意的澄清效果,还能呈现菠萝原汁的亮黄色。 相似文献
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菠萝果汁分别接种干酪乳杆菌、植物乳杆菌、嗜酸乳杆菌和肠膜明串珠菌进行发酵,研究菠萝果汁发酵过程中理化品质和感官品质的变化规律。结果表明,4种乳酸菌在菠萝果汁中生长良好,发酵24 h,植物乳杆菌和肠膜明串珠菌的活菌数对数值均已超过8.3;经乳酸菌发酵后,菠萝果汁的pH、维生素C(VC)含量均显著降低,而总酸、可溶性固形物、总酚、1,1-二苯基-2-三硝基苯肼(DPPH)自由基清除率显著升高。其中,植物乳杆菌具有较强的产酸能力,肠膜明串珠菌能够延缓VC的流失。在对感官品质影响方面,4种发酵菠萝果汁之间存在差异,经肠膜明串株菌发酵的菠萝果汁感官评价较优(79.79分),而经嗜酸乳杆菌能够更好地保留菠萝果汁特有的挥发性香气成分。研究结果为益生菌菠萝果汁产品的开发提供参考依据和技术支持。 相似文献
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菠萝果汁抑制香蕉加工过程中酶褐变的初步研究 总被引:4,自引:0,他引:4
对菠萝果汁抑制香蕉片和香蕉果浆的酶褐变效果进行了研究。以蒸馏水、pH3.9柠檬酸溶液、10mmol/L异抗坏血酸溶液、5mmol/L亚硫酸氢钠溶液、新鲜菠萝果汁和热处理菠萝果汁分别对香蕉片和香蕉果浆进行处理,然后在不同时间测定香蕉片和香蕉果浆的L值。结果表明,新鲜菠萝果汁和热处理菠萝果汁具有相同的酶褐变抑制效果,而且显著优于蒸馏水、pH3.9柠檬酸溶液和10mmol/L异抗坏血酸溶液,与5mmol/L亚硫酸氢钠溶液的效果相似;其抑制酶褐变的机理不是单一的抗坏血酸或低pH值或柠檬酸或蛋白酶的作用,可能是多因素综合作用的结果。 相似文献
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采用植物乳杆菌(Lactobacillus plantarum)和酿酒酵母(Saccharomyces cerevisiae)分别进行单菌与混菌发酵菠萝汁,并比较分析不同接菌方式下菠萝汁的发酵性能及发酵体系中的产物。结果表明,相同接种量发酵72 h后,植物乳杆菌单独发酵活菌数可达108 CFU/mL,分别约为酿酒酵母单独发酵和二者混合发酵活菌数的3倍和10倍;植物乳杆菌的接入使发酵液pH降至3.21,而酿酒酵母的接入使菠萝汁中氨基酸态氮降至3.15×10-4 mg/L,糖类物质几乎被消耗殆尽。发酵产物分析结果发现,植物乳杆菌单独发酵产生大量乳酸(每升增加12.02 g/L)和少量乙酸(每升增加0.40 g/L),影响了口感,而酿酒酵母单独发酵则使菠萝汁中原有的香气物质损失较多(4种)。综合分析,采用二者混合发酵,既可保有菠萝本身的营养物质和特有香气,又可赋予其一定的发酵风味,获得口感良好的菠萝发酵饮品。 相似文献
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Rosnah Shamsudin Chia Su Ling Noranizan Mohd Adzahan Wan Ramli Wan Daud 《Journal of food engineering》2013
The rheological behaviour of Yankee pineapple juice was examined for the effect of ultraviolet (UV) irradiation (53.42 mJ/cm2) and compared with untreated juice and a thermally pasteurized (80 °C for 10 min) juice. A rheological test was performed on all types of juice in the temperature range 5 °C to 25 °C using a concentric cylinder rheometer at a shear rate range of 10–290 s−1. The comparative analysis found that the best flow curves were described by the Bingham model with an initial shear stress. The entangled pulps in the juices prevented free flow at zero shear rate. There was no significant variation between the plastic viscosities of the untreated and UV-irradiated juice at all temperatures. The activation energy (Ea) of the untreated, UV-irradiated and thermally pasteurized juice was 6.80, 8.19 and 8.50 kJ/mol respectively. 相似文献
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通过测定饮料的混浊稳定性,比较几种亲水胶体对香蕉饮料的稳定作用,选择其中几种稳定效果较好的胶进行复配实验,最终确定添加0.1%的胶体组合A∶D∶B=2∶1∶2作为香蕉饮料的稳定剂。 相似文献