超滤和反渗透技术在果汁生产中的应用

根据超滤膜和反渗透膜的特点，介绍了超滤(UF)和反渗透(RO)膜技术在苹果汁、橘子汁、山楂汁等果汁生产中的应用。     

果汁浓缩技术概述

介绍了果汁浓缩技术的发展现状,包括真空蒸发技术、冷冻浓缩技术、膜技术在果汁浓缩过程中的应用,以及各浓缩技术的研究的现状;膜技术中,重点介绍了渗透蒸馏、膜蒸馏及集成膜技术的发展现状;比较了各浓缩技术的优缺点。从果汁市场的扩大和产品质量要求的角度指出了膜技术在果汁行业中的应用前景。     

膜分离技术在食品工业中的应用

阐述了主要的几种膜技术的分离原理，特性及其在食品工业中的应用，重点介绍了膜技术在乳品加工，果汁加工，酒类生产中的应用。     

膜技术及其在水果加工中的应用

论述了膜技术在水果加工中的应用,对果汁浓缩、果汁澄清、芳香物质及色素的提取、果汁的脱苦脱酸以及微生物检验等方面的应用效果和特点作了介绍.膜技术的应用给我国水果深加工和市场带来了巨大商机.     

膜技术及其在水果加工中的应用

论述了膜技术在水果加工中的应用，对果汁浓缩、果汁澄清、芳香物质及色素的提取、果汁的脱苦脱酸以及微生物检验等方面的应用效果和特点作了介绍。膜技术的应用给我国水果深加工和市场带来了巨大商机。     

膜分离技术及其在农产品加工中的应用分析

正膜分离技术有其显著的技术应用有效性,本文主要分析超滤(UF)膜技术、微滤(MF)膜技术、反渗透(RO)膜技术,重点介绍膜分离技术在牛初乳加工和果汁加工中的应用,以期提高其技术应用有效性。常见的膜分离技术超滤(UF)膜技术超滤分离技术目前是膜分离技术中应用最广泛的一种分离手段。在国外,超滤膜分离技术在农产品加工行业已成功地应用在植物蛋白的分离、果汁的澄清、蔬菜汁的浓缩、酶精制、发酵液和菌体的浓缩及乳制品等方面。微滤(MF)膜技术     

壳聚糖固定化果胶酶在枇杷果汁澄清中的应用

以戊二醛为交联剂,壳聚糖为载体固定化果胶酶,对其在枇杷果汁澄清中的应用进行研究。结果表明:固定化果胶酶澄清枇杷果汁的工艺条件为:固定化酶浓度为50 g/L(果汁),果汁pH值为3.8,果汁体积分数为60%,酶解温度和时问分别是50℃和2 h。固定化果胶酶比游离酶处理枇杷果汁的澄清效果好,固定化酶酶解后果汁的糖度没有变化,酸度略有下降,渣汁分层速度加快,果汁色泽由褐色转变为黄色,冷热稳定性也提高了。     

果汁饮料混浊，沉淀的原因及稳定性的探讨

随着改革开放,我国引进了国外的先进生产设备和技术,使我国的果汁加工工业得已迅速的发展,加工的果汁品种也随之增多。如浓缩苹果汁、柑桔汁、刺梨汁、阳梨汁、葡萄汁、哈密瓜汁、山楂汁、猕猴桃汁、黑加仑汁、沙棘汁等相继问世。部分用国产设备生产的浓缩果汁也随之投入市场。以天然果     

球形交联壳聚糖固定化果胶酶在枇杷果汁澄清中的应用

以戊二醛为交联剂,NaOH与乙醇为凝结液组成成分,壳聚糖为载体制备了球形交联壳聚糖固定化果胶酶,对其在枇杷果汁澄清中的应用进行了研究。结果表明,固定化果胶酶澄清枇杷果汁的工艺参数为:固定化酶质量浓度为50 g/L(果汁),果汁pH值为3.0,果汁浓度为40%,酶解温度和时间分别是50℃和1.5 h,在重复使用7次后果汁透光率仍保留有75.8%。固定化果胶酶比溶液酶处理枇杷果汁的澄清效果好,酶解后果汁的糖度与酸度没有变化,汁渣分层速度快,果汁色泽为淡黄色,冷热稳定性也有所提高。     

复合龙眼汁运动饮料的研制

对以龙眼汁、三华李汁为主要原料经复配生产一种复合果汁运动饮料进行了研究,确定了不同果汁的添加比例、生产工艺及产品的质量标准。试验表明,当龙眼汁为30%、三华李为20%时生产的复合龙眼汁运动饮料综合评价质量最好。     

Application of Membrane Separation in Fruit and Vegetable Juice Processing: A Review

Fruit and vegetable juices are used due to convenience. The juices are rich in various minerals, vitamins, and other nutrients. To process the juices and their clarification and/or concentration is required. The membranes are being used for these purposes. These processes are preferred over others because of high efficiency and low temperature. Membranes and their characteristics have been discussed in brief for knowing suitability of membranes for fruit and vegetable juices. Membrane separation is low temperature process in which the organoleptic quality of the juice is almost retained. In this review, different membrane separation methods including Microfiltration, Ultrafiltration, and Reverse osmosis for fruit juices reported in the literature are discussed. The major fruit and vegetable juices using membrane processes are including the Reverse osmosis studies for concentration of Orange juice, Carrot juice, and Grape juice are discusses. The Microfiltration and Ultrafiltration are used for clarification of juices of mosambi juice, apple juice, pineapple juice, and kiwifruit juice. The various optimized parameters in membranes studies are pH, TAA, TSS, and AIS. In this review, in addition to above the OD is also discussed, where the membranes are used.     

Potential of Membrane Distillation for Production of High Quality Fruit Juice Concentrate

Fruit juices are generally concentrated in order to improve the stability during storage and to reduce handling, packaging, and transportation costs. Thermal evaporation is the most widely used technique in industrial fruit juice concentrate production. In addition to high energy consumption, a large part of the characteristics determining the quality of the fresh juice including aroma, color, vitamins, and antioxidants undergoes remarkable alterations through the use of high operation temperatures. Increasing consumer demand for minimally or naturally processed stable products able to retain as much possible the uniqueness of the fresh fruit has engendered a growing interest for development of nonthermal approaches for fruit juice concentration. Among them, membrane distillation (MD) and its variants have attracted much attention for allowing very high concentrations to be reached under atmospheric pressure and temperatures near ambient temperature. This review will provide an overview of the current status and recent developments in the use of MD for concentration of fruit juices. In addition to the most basic concepts of MD variants, crucial suggestions for membrane selection and operating parameters will be presented. Challenges and future trends for industrial adaptation taking into account the possibility of integrating MD with other existing processes will be discussed.     

Bergamot: A source of natural antioxidants for functionalized fruit juices

Bergamot is a common Italian citrus fruit, cultivated almost exclusively to produce essential oils; the juice is considered a waste product, which represents a serious environmental and economic problem for the industries. The aim of this study was to re-evaluate bergamot juice through its chemical characterization and its use to enrich and fortify fruit juices. To investigate this, apples and apricots were used for the laboratory-scale production of fruit juice, following both the traditional industrial recipe and those with the addition of bergamot juice at 10% or 20%, together with or in order to replace the synthetic additives normally used in the industrial process (ascorbic acid and citric acid). The ascorbic acid content and the antioxidant activity were measured during the different steps of juice production and after storage at 37 °C for 15 days to evaluate juice shelf-life. Apricot and apple juices fortified with bergamot juice showed a significant increase in their antioxidant properties and a decreased reduction in ascorbic acid content after the typical production steps. All of the results obtained support the hypothesis that the addition of bergamot juice to juices preserves their ascorbic acid content from thermal degradation and contributes to enhance the antioxidant activity, ensuring a product much richer in antioxidants and ascorbic acid. A preliminary consumer test encouraged the production of bergamot fortified fruit juices. Finally, this is the first time that isorhoifolin and rutin have been detected in bergamot juice.     

膜分离技术在果蔬汁生产中的应用

介绍了膜分离技术在果蔬菜汁澄清，脱苦，浓缩等方面的应用，探索了利用膜联合过程生产高品质质果蔬汁的实际可能性。     

Ultraviolet radiation as a non-thermal treatment for the inactivation of microorganisms in fruit juice

Fruit juices can be processed using ultraviolet (UV-C) light to reduce the number of microorganisms. The UV-C wavelength of 254 nm is used for the disinfection and has a germicidal effect against microorganisms. A novel turbulent flow system was used for the treatment of apple juice, guava-and-pineapple juice, mango nectar, strawberry nectar and two different orange and tropical juices. In comparison to heat pasteurization, juices treated with UV did not change taste and color profiles. Ultraviolet dosage levels (J L^− 1) of 0, 230, 459, 689, 918, 1 148, 1 377, 1 607 and 2 066 were applied to the different juice products in order to reduce the microbial load to acceptable levels. UV-C radiation was successfully applied to reduce the microbial load in the different single strength fruit juices and nectars but optimization is essential for each juice treated. This novel UV technology could be an alternative technology, instead of thermal treatment or application of antimicrobial compounds.

Industrial relevance

This novel UV-C system can be applied successfully to the Food Industry. UV-C can be effectively used to reduce the number of spoilage and pathogenic bacteria, as well as yeasts and moulds in different kinds of fruit juices.     

Variety‐based discrimination of apple juices by an electronic nose and gas chromatography–mass spectrometry

The variety of raw material plays a crucial role in the quality and authenticity of fruit juices and juice products. To characterise and classify apple juices according to variety on the basis of their volatile compounds, electronic nose (EN) and gas chromatography–mass spectrometry (GC‐MS) were applied to detect the apple juices prepared by eight different varieties. The EN was used to analyse the mixture of volatile compounds as a whole and enabled rapid classification of juice samples when coupled with linear discriminant analysis (LDA). LDA showed a perfect discrimination of apple juices based on varieties. GC‐MS was utilised to illustrate the differences of volatile compounds among juice samples. Identification of volatile compositions and their contents provides useful access to differentiate juices from different varieties.     

果汁发酵生产细菌纤维素

为提高果汁发酵生产细菌纤维素的产量,开发特色纤维素功能性食品,以葡糖醋杆菌CGMCC 3917为实验菌种,以苹果汁和梨汁为发酵培养基生产细菌纤维素(BC),研究果汁用量和酵母膏添加量对细菌纤维素产量的影响,比较分析两种果汁生产的细菌纤维素在产量、结构和性质方面的差别。结果表明：梨汁发酵生产的细菌纤维素产量明显高于苹果汁,可达46.343g/100mL;其BC干膜复水率显著高于苹果汁,BC干膜的总糖含量稍高于苹果汁。两种果汁发酵生产的细菌纤维素在湿膜持水量及干膜的纤维素含量、蛋白质含量、脂肪含量以及微观结构上没有明显差异。     

OPTIMUM QUALITY PARAMETERS OF MUSCADINE GRAPE JUICES, BEVERAGES, AND BLENDS

Cold- and hot-pressed juices from black and bronze muscadine grapes were tested to determine optimum Brix/acid ratios, optimum juice level in beverages, and optimum blend ratios with other fruit juices. The optimum Brix/acid ratio, regardless of cultivar or process, was approxi-mately 30 with. an acceptable range from 25. to 35. Increased sweetness due to sugar addition was perceptible, even when balanced with addition of acid. Optimum dilution was dependent upon cultivar and process. Red hot-pressed juice was most acceptable at a 25% juice level, when Brix/acid was adjusted to 30. Optimum blends with fruit juices varied with muscadine juice color and process. Best blends were muscadine juices and commercial grape juices, orange juice, and pineapple juice. Muscadine grape-grapefruit juice blends had poor acceptability.     

Survey of South African fruit juices using a fast screening HILIC-MS method

Adulteration of fruit juices – by the addition of sugar or other less expensive fruit juices as well as preservatives, artificial sweeteners and colours – was tested for by using a developed screening method. The method employs hydrophilic interaction liquid chromatography-mass spectrometry (HILIC-MS) using electrospray ionisation in the negative mode and ultraviolet light detection. Different fruit juices can be differentiated by the content of marker compounds like sorbitol, certain phenolic molecules and their saccharide profile. This method was used to test 46 fruit juice samples from the retail market as well as 12 control samples. The study focused on the main types of fruit juices consumed on the South African market including apple, orange, grape and blends of these juices with other fruits like mango, pear and guava. Overall, the 46 samples tested mostly agreed with label claims. One grape juice sample was adulterated, probably with apple juice. Natamycin above the legal limits was found in two samples. In addition, two samples contained natamycin and one sample benzoate without it being indicated on the label. The method is well suited as a quick screening method for fruit juice adulteration and if used routinely would reduce fruit juice adulteration without the cost of the current array of tests needed for authenticity testing.     

果蔬饮料发展空间广阔

<正> 果蔬汁及菜蔬汁饮料是饮料工业的重要组成部分,随着食品工业的发展,人们生活习惯和饮食结构的改变,果蔬汁饮料在人们生活中所占的位置日益突出。 行业现状分析 自20世纪20年代起,果蔬原汁的消费量开始迅速增长。1971年,世界果蔬汁罐头生产量为350万吨,约占罐头食品产量的10%。据世界银行统计,1970～1986年问,世界果汁的年增长率为2.9%;到了20世纪90年代,提高到3.7%。1990年,世界果汁的产晕为7,200万吨,总贸易量为900万吨;1995年和2000年,世界果蔬汁的总产量分别为8,680万吨和1亿吨,总贸易量分别达到1,050万吨和1,200万吨。