共查询到20条相似文献,搜索用时 31 毫秒
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以菠萝汁和牛肉为原料,研究菠萝汁中菠萝蛋白酶对牛肉的嫩化作用,得到了嫩化的最佳工艺:菠萝汁浓度6%、时间60min、温度50℃、pH7.0。在此条件下,牛肉剪切力可降低50% 左右。对菠萝汁、生姜汁、木瓜蛋白酶嫩化产品与对照组进行了风味、色泽、剪切力的对比,结果表明:菠萝汁较生姜汁能够显著(p ≤ 0.05)提高产品的风味,相比木瓜蛋白酶及对照组其风味也有不同程度提高;菠萝汁、生姜汁、木瓜蛋白酶都能极显著(p ≤ 0.01)的提高产品的嫩度,而三种嫩化产品之间嫩度没有显著差异;用菠萝汁嫩化牛肉,在牛肉腌制后,其色度的b 值和a/b 值相对于对照组有极显著(p ≤ 0.01)提高,而在煮制后,只有b 值和对照组有显著(p ≤ 0.05)差异,而a/b 值无显著差异,表明用菠萝汁嫩化牛肉不会对产品的色泽造成不良影响。 相似文献
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Efficacy of phytic acid as an inhibitor of enzymatic and non-enzymatic browning in apple juice 总被引:1,自引:0,他引:1
Browning decreases the commercial value of apple juice, and therefore colour preservation during processing and storage is the main objective of manufacturers. In this study, the efficacy of phytic acid as a browning inhibitor for use on apple juice was investigated. Browning of apple juice treated with phytic acid was monitored during processing and storage. 0.1 mM Phytic acid inhibited the polyphenol oxidase (PPO) from the apple juice by 99.2%. Consequently, the apple juice treated with phytic acid had significantly lower browning formation during processing and after 6 months of storage at room temperature compared with the control (p<0.05). Results indicate that this is a promising way to inhibit browning in apple juice. 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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苹果原浆抗氧化防褐变及稳定性试验 总被引:6,自引:0,他引:6
新鲜苹果加工成果汁,由于酶促褐变或非酶促褐变常变色,呈褐色,内色或黑色。加入一定量的Vc或L-cys会抑制其褐变,在新鲜汁中加入不同的增稠剂,会提高其稳定性。 相似文献
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《Food Reviews International》2013,29(2):112-133
Pineapple processing plays an important role in juice preservation. Because the quality of the pineapple juice is affected by the processing technology applied, the effects of pasteurization and other preservation methods on the overall juice quality were discussed. During juice processing, microorganisms are destroyed and chemical changes occur. To optimize processing conditions, knowledge of the kinetics of these reactions is needed, but as of yet, data on the degradation of the amino acids and vitamin C and the change in sugar contents during pineapple juice pasteurization are scanty. Furthermore, the kinetics of hydroxymethylfurfural production should be investigated by a precise technique such as high-performance liquid chromatography. 相似文献
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在不影响雪莲果果酒发酵过程和品质的前提下,通过添加抗坏血酸、柠檬酸、蜂蜜、菠萝汁等抗褐变剂来解决雪莲果果酒生产中的褐变问题,得到营养成分损失少、风味佳、色泽鲜亮的雪莲果果酒。结果表明,抑制雪莲果褐变程度的先后顺序为柠檬酸>抗坏血酸>菠萝汁雪莲混合比,蜂蜜在雪莲果酒陈酿期会产生深色物质,不适宜作为雪莲果果酒的抗褐变剂。影响感官的顺序分别为菠萝汁雪莲混合比>抗坏血酸>柠檬酸,最后得出抑制雪莲果酒褐变的最佳组合为抗坏血酸的添加量1.00%,柠檬酸的添加量0.75%,菠萝雪莲混合比为1:4。 相似文献
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为研究不同褐变抑制剂对苹果多酚氧化酶(PPO)活性的抑制机理,采用磷酸缓冲液构建苹果汁模拟体系,选取苹果中含量较多的酚类物质绿原酸作为试验对象,以磷酸缓冲液为苹果汁模拟体系,选取4-己基间苯二酚(4-HR)、草酸、苯甲酸和对甲氧基苯甲酸为抑制剂,通过模拟试验研究抑制剂对绿原酸模拟苹果汁酶促褐变特性的影响,揭示抑制剂对苹果汁PPO的作用机理。结果表明,抑制剂对PPO的抑制机理差异较大,其中4-HR和草酸对PPO的抑制作用为竞争性抑制,植酸为混合性抑制,而苯甲酸为非竞争性抑制。该研究可为利用抑制剂控制苹果汁褐变提供理论依据。 相似文献
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为研究氧化白藜芦醇(oxyresveratrol,OXY)对苹果褐变的抑制作用,采用不同浓度的OXY对鲜切苹果、苹果汁进行处理,探讨在不同储藏阶段切片色度和果汁褐变度变化情况及OXY对苹果汁内多酚氧化酶(polyphenol oxidase,PPO)和过氧化物酶(peroxidase,POD)活性的影响。结果表明:OXY可改善苹果切片的感官品质,显著延缓切片L*值的降低(P<0.05),抑制a*、b*、ΔE值的升高(P<0.05)。同时,OXY还能显著降低苹果汁褐变度(P<0.05),显著抑制苹果汁内PPO和POD活性(P<0.05)。综上,OXY能有效抑制鲜切苹果片及苹果汁褐变,其作用机制可能是通过抑制苹果内PPO和POD活性实现。 相似文献
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以苹果中含量较多的儿茶素为研究对象,以磷酸缓冲液为苹果汁褐变模拟体系,在多酚氧化酶(polyphenol oxidase,PPO)酶促诱发儿茶素后,钝化PPO,通过色差仪连续测定模拟体系亮度(L*)值、红度(a*)值、黄度(b*)值及总色差(ΔE*)值的变化趋势,研究酶促诱发条件对模拟果汁体系非酶褐变特性的影响。结果表明:酶促诱发时间及诱发体系温度对儿茶素参与的非酶褐变无显著性影响(P>0.05),而酶促诱发体系pH值以及儿茶素浓度对模拟体系褐变程度影响显著(P<0.05),pH 4.0时,模拟果汁体系褐变程度较大,褐变程度随儿茶素浓度的增大而增强;本实验同时发现,PPO诱发儿茶素发生非酶聚合,并与聚合产物相互作用而沉淀,导致果汁产生后浑浊。 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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The kinetics of non-enzymatic browning in apple juice concentrates were investigated. The effect of aw (in the range of 0.74–0.99) and/or reactant concentration on brown pigment formation was monitored under isothermal heat treatment at four temperatures (60, 70, 80 and 90 °C) in apple juice solutions having either the same or different concentrations of reactant solutes. The extent of the Maillard reaction was evaluated by spectrophotometric measurements at 420 nm (A420). The absorbance–time curves were fitted to five different kinetic models (zero and first order, weibull, logistic and the parabolic model) and estimates of browning rate constants and other model parameters were obtained. Regression analysis revealed that the logistic model was the most appropriate for describing browning in apple juice. The initial reactant concentration, but not water activity, had a significant effect on the colour change of apple juice. The processing temperature also had a strong impact on browning kinetics. Secondary models, expressing the dependence of the best fitted primary model parameters on temperature and aw, were further developed and validated by comparing the predicted model parameters with the values observed in independent isothermal experiments. Finally, the derived model was further evaluated against the observed browning responses of apple juice under dynamic heating conditions, underlining the applicability of the developed model as a practical prediction tool for the study of non-enzymatic browning. 相似文献
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菠萝汁腌制牛肉,既可以满足牛肉的嫩化效果,提升牛肉品质,又可以增加牛肉的风味,同时符合当前人们对健康追求的趋势。实验选用牛后腿肉,从剂量、温度、时间三个方面研究菠萝汁对牛肉的嫩化效果。通过质构仪测量,对比牛肉嫩化后咀嚼性、弹性、硬度的大小变化,以及感官评定,分析得出菠萝汁嫩化牛肉的最佳方案。 相似文献
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This research studied the influence of treatment with ascorbic acid, citric acid, and calcium lactate dipping and cassava starch edible coatings on quality parameters and shelf life of fresh-cut pineapple in slices during 12 d at 5 °C. After previous tests, the treatments selected for this study were samples dipped into antibrowning solution with 0.5% of ascorbic acid and 1% of citric acid, with and without 2% of calcium lactate and coated with 2% of cassava starch suspensions. Changes in weight loss, juice leakage, mechanical properties (stress at failure), color parameters (L* and H*), ascorbic acid content, sensory acceptance, and microbial growth of fruits were evaluated. Samples only treated with antibrowning agents were used as control. Edible coatings with and without calcium lactate were efficient in reducing weight loss, juice leakage, and maintaining firmness during storage. However, these samples showed more browning and the ascorbic acid content was reduced. All treatments presented good sensory acceptance (scores above 6). The determining factor of shelf life of pineapple slices was the microbial spoilage. A shelf life of 8 d was obtained for pineapple slices only treated with antibrowning agents. On the other hand, coated samples showed a reduced shelf life of 7 d and higher yeast and mold growth. Thus, although cassava starch coatings were efficient in reducing respiration rate, weight loss, and juice leakage and maintained mechanical properties, these treatments were not able to increase the shelf life of minimally processed pineapple. Practical Application: Pineapple fruit is highly appreciated for its aroma, flavor, and juiciness, but its immediate consumption is difficult. Therefore, pineapple is a potential fruit for minimal processing. However, shelf life of fresh-cut pineapple is very limited by changes in color, texture, appearance, off-flavors, and microbial growth. The use of edible coatings as gas and water vapor barrier and antibrowning agents can extend the storage time and maintain the quality of fresh-cut produce. Cassava starch and alginate coatings are alternative to preserve minimally processed pineapples without changing the quality parameters of fresh fruit. Thus, this study is useful for consumers and fresh-cut industry interested in knowing factors affecting shelf life and quality of fresh-cut pineapple. 相似文献