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.     

Consumer Liking of Fruit Juices with Different Açaí (Euterpe oleracea Mart.) Concentrations

ABSTRACT:  Overall liking, flavor, and perceived healthiness of one newly developed fruit juice with high açaí content (40% açaí) and 5 commercially available fruit juices with lower (4% to 20%) açaí concentrations were evaluated by consumers in Belgium. General trends for the overall sample were examined by means of analysis of variance, whereas individual consumer preferences were evaluated using internal preference mapping and hierarchical cluster analysis. The relative contribution of flavor and perceived health benefits as predictors of consumers' overall liking of the 6 açaí-based fruit juices was estimated through linear regression analysis. The results showed a negative relationship between the juices' overall liking and their açaí concentrations. Although the vast majority of consumers preferred the juices having a low açaí content (4% to 5% açaí), a small consumer segment liked the juice with 40% açaí. Flavor or taste experience superseded consumers' perceived health benefits as the primary determinant of the fruit juices' overall liking. The impact of perceived health benefits on the overall liking of the açaí juices decreased with higher taste dissatisfaction.     

雪莲果发酵酒的防褐变技术研究

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。     

Freeze Concentration of Pineapple Juice

Juice, extracted from fresh Costa Rican pineapples using a commercial extractor, was adjusted by finishing and centrifugation to two pulp levels, 12% and 2% by volume. Physical, chemical and sensory differences were measured in heat stabilized single strength juices, evaporator concentrated, and freeze-concentrated juices. Results indicated no significant differences between samples for Brix, % acid, total hexose, vitamin C, browning index, color, viscosity. Pulp content was lower in both freeze- and evaporator-concentrated samples. Significant (P < 0.01) flavor differences were detected between freeze-and evaporator-concentrated juices. Juices were ranked according to highest degree of fresh fruit taste as follows: (1) high pulp single strength, (2) freeze concentrate high pulp, and (3) evaporator concentrate high pulp. Flavor of reconstituted freeze-concentrated juice was comparable to single strength juice and preferable to evaporator concentrate.     

葡萄百香果酒的酿造工艺研究

以葡萄和百香果为原料,复合发酵开发一款风味独特的果酒。通过单因素试验和二次通用旋转组合试验优化复合果酒酿造工艺,并对产品质量进行评定。结果表明,葡萄百香果酒的最佳工艺参数为酵母添加量（葡萄酒活性干酵母∶耐高温活性干酵母=1∶1）0.4%、葡萄汁:百香果汁1∶4（V/V）,初始糖度24 °Bx、发酵温度23 ℃、发酵时间7 d,在此优化条件下,得到的葡萄百香果酒果味浓郁、色泽金黄、酸甜适中、口感清爽,感官评分为84.35分,其酒精度为（12.3±1.3）%vol,糖含量（3.08±0.38）g/L,总酸含量为（6.65±0.29）g/L,符合国家标准要求,是一款品质较佳的风味果酒。     

Grape,apple and pineapple juice characterisation and detection of mixtures

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.     

Development and optimisation by means of sensory analysis of new beverages based on different fruit juices and sherry wine vinegar

BACKGROUND: Despite the long history of sherry wine vinegar, new alternatives of consumption are being developed, with the aim of diversifying its market. Several new acetic‐based fruit juices have been developed by optimising the amount of sherry wine vinegar added to different fruit juices: apple, peach, orange and pineapple. Once the concentrations of wine vinegar were optimised by an expert panel, the aforementioned new acetic fruit juices were tasted by 86 consumers. Three different aspects were taken into account: habits of consumption of vinegar and fruit juices, gender and age. RESULTS: Based on the sensory analysis, 50 g kg^?1 of wine vinegar was the optimal and preferred amount of wine vinegar added to the apple, orange and peach juices, whereas 10 g kg^?1 was the favourite for the pineapple fruit. Based on the olfactory and gustatory impression, and ‘purchase intent’, the acetic beverages made from peach and pineapple juices were the most appreciated, followed by apple juice, while those obtained from orange juice were the least preferred by consumers. CONCLUSION: New opportunities for diversification of the oenological market could be possible as a result of the development of this type of new product which can be easily developed by any vinegar or fruit juice maker company. © 2012 Society of Chemical Industry     

Use of a multivariate approach to assess the incidence of Alicyclobacillus spp. in concentrate fruit juices marketed in Argentina: results of a 14-year survey

The purpose of this study was to determine the incidence of Alicyclobacillus spp. in fruit/vegetable juices (concentrated pulps and clarified and non-clarified juices) marketed in Argentina between 1996 and 2009.The presence of Alicyclobacillus was determined in a total of 8556 samples of fruit and vegetable juices (apple, pear, grape, peach, blend of juices, tangerine, pineapple, orange, mango, plum, guava, apricot, lemon, banana, kiwi, carrot, strawberry, grapefruit, and beetroot) collected in seven Argentinean provinces. Multiple factor analysis (MFA) was carried out on a data matrix that contained the percentage of positive samples, type of juice, raw material and production year.Except for kiwi and orange, Alicyclobacillus was found in juices from all the evaluated raw materials. The highest percentage of positive samples was found for beetroot, strawberry, banana, peach, mango, carrot and plum juices. The percentage of positive samples for these juices ranged from 100% to 24%.Furthermore, the application of multivariate techniques provided an insight on the relationship between the incidence of Alicyclobacillus and production variables. This approach enabled the identification of the most relevant variables that increased the percentage of positive samples among the juices, which could help in developing strategies to avoid the incidence of this bacterium.By means of hierarchical cluster analysis seven groups (clusters) of juices which showed different percentages of positive samples for Alicyclobacillus spp. were identified. This analysis showed that pineapple, peach, strawberry, mango and beetroot juices had higher rates of positivity for Alicyclobacillus than the rest of the evaluated juices. MFA analysis also showed that some clear relationships could be highlighted between the percentage of samples positive for Alicyclobacillus and five types of fruit juices (strawberry, beetroot, grapefruit, pineapple and mango). It was observed that a large proportion of juices produced in 2000, 2005 and 2008 were located in clusters with higher incidence of Alicyclobacillus spp., whereas a larger proportion of clarified concentrate juice and concentrate pulp samples showed higher probability of incidence of Alicyclobacillus in these products. Data presented in this study brings a contribution to the ecology of Alicyclobacillus in fruit/vegetable juices marketed in Argentina. This information would be useful to enhance the microbiological stability of fruit juices regarding the presence of Alicyclobacillus spp.     

Impact of Multicolored Asian Lady Beetles on the Sensory Properties of Concord and Niagara Grape Juice

ABSTRACT: The presence of Multicolored Asian Lady Beetles (MALB) in grape juice is increasingly problematic. The overall objective of this study was to determine the specific sensory impacts of MALB on Concord and Niagara grape juice. The aroma threshold for MALB-taint in both juices was determined and expressed as the best estimate threshold (BET). The aroma BET for MALB-taint in Concord grape juice was 1.8 and 0.65 MALB/L Niagara grape juice. The specific sensory attributes of the grape juices influenced by the presence of MALB were then described. In Concord grape juice, trained panelists (n = 9) found significant increases in vegetal aroma and earthy flavor as MALB concentration increased from 0.45 to 7.2 MALB/L. In Niagara grape juice, with increasing MALB concentration, trained panelists (n = 8) indicated significant decreases in honey and sweetness with corresponding increases in sourness, astringency, and vegetal and earthy aromas and flavors (P < 0.05). For both aroma and flavor, consumer rejection studies were performed using paired preference comparisons of control juice to MALB-tainted grape juice. For Concord grape juice, consumers (n = 60) rejected the aroma of MALB-tainted juice at 1.8 MALB/L and the taste/flavor of the MALB-tainted juice at 3.6 MALB/L. For Niagara juice, consumers rejected the aroma of the juice at 3.6 MALB/L. This study demonstrated the presence of MALB negatively impacts the sensory properties of Concord and Niagara grape juice. Grape juice processors may use this research for quality control measures and for establishing tolerance limits. Practical Application: The Multicolored Asian Ladybeetle (MALB), initially used for biocontrol, has been shown in previous literature to impact the sensory properties of wines. The presence of MALB in grape juice is now becoming problematic; however, there is little research describing the specific sensory impacts of MALB on grape juice. This study examined the sensory impact of MALB on both Concord and Niagara grape juice. While the threshold and trained panel evaluations from this study provide valuable sensory profile information, grape juice processors may be particularly interested in the consumer rejection of MALB-tainted grape juice as they can use this research for quality control measures and for establishing tolerance limits.     

Effect of a health claim on consumer acceptance of exotic Brazilian fruit juices: Açaí (Euterpe oleracea Mart.), Camu-camu (Myrciaria dubia), Cajá (Spondias lutea L.) and Umbu (Spondias tuberosa Arruda)

This study evaluates the influence of information on the health benefits for acceptance of four exotic tropical fruit juices: açaí, camu-camu, cajá and umbu. One hundred and six evaluators participated in the tests and sensory acceptability of the four juices in relation to the overall impression was assessed using a hedonic scale of nine points. Testing was conducted in three stages: the first with no information, the second with the information on juice flavor and the last with the information on health benefits from consumption of such juice. Between the second and third session the evaluators were asked to fill out a questionnaire in order to obtain its socioeconomic and cultural profile. It was observed by internal preference mapping that the cajá and umbu juices showed higher sensory acceptance in all sessions. Camu-camu juice had the highest sensory rejection. It was found that the information on the taste of açaí and cajá juices positively influenced consumer acceptance. However the influence of information on health benefits can be observed for all evaluated juices, but despite this information the camu-camu juice continued in the area of sensory rejection (hedonic scores below 5). In the questionnaire it can be observed that the main factor of motivation for consumption of fruit juice is taste, and not the health benefits. It was concluded that the information of health benefits can positively influence sensory acceptance, provided there is sensory pleasure.     

Cashew apple juice: its use in fortifying the nutritional quality of some tropical fruits

The physico-chemical properties of some tropical fruits (pineapple, orange, grape, mango and lemon) were analyzed and compared with those of cashew apple. Cashew apple juice was found to contain the highest amount of vitamin C (203.5 mg/100 ml) of edible portion. Orange, grape, pineapple, mango and lemon contained average values of 54.7 mg, 45.0 mg, 14.70 mg, 30.9 mg and 33.7 mg vitamin C per 100 ml of juice respectively. Obviously, cashew apple juice contains almost four times the amount of vitamin C in the popular citrus fruits and more than four times as much vitamin C as in other fruits. Hence, when cashew apple was blended with other tropical fruits it boosted their nutritional quality. On the other hand, these fruits improved the acceptability of cashew juice in terms of taste and flavour. The blends, even though significantly different (P <0.05) in taste, colour and mouthfeel, were all acceptable to consumers with no significant difference (P>0.05) in overall acceptability. Received: 16 August 1999 / Revised version: 2 November 1999     

Free sugars determination by HPLC in pineapple products

Free sugars have been determined by HPLC in fresh pineapple fruit, freshly extracted pineapple juice (home-made), pineapple juice concentrate (for industrial use), commercial pineapple juices and nectars. In natural samples, intermediate products and commercial juices the dominant sugar was sucrose, followed by fructose and glucose, both of which were found in similar concentrations. However, the sugar content of nectars analyzed was highly variable. The presence of maltose in nectar samples is a clear indication of the addition of sugars from corn syrup. We have found a fructose/glucose ratio close to 1, and the coefficient fructose plus glucose/sucrose close to 1, both of which are a good index of authenticity of pineapple juices.     

蕴含热带风情的美味——西番莲

<正> 厄瓜多尔的西番莲果(热情果)以其独特的风味,芬芳的香气,赢得了国际市场的欢迎。而热带气候,则给予了西番莲果行天独厚的生长条件,没有季节性的限制,使其成为世界上较大的西番莲果生产国之一。厄瓜多尔的西番莲浓缩果汁,在世界市场上占有极大的份额。此外,它还出口新鲜的西番莲果、西番莲籽和果香。     

菠萝-香蕉复合纯果汁生产工艺及冻藏研究

为了研究菠萝-香蕉复合纯果汁饮料的生产工艺,以菠萝和香蕉为主要原料经打浆、过滤和调配后,添加适量的纯奶,以蔗糖为调味剂配制成复合纯果汁。通过正交试验确定了该复合纯果汁的最佳配方为：菠萝：香蕉为6：1,纯奶添加量为10％,蔗糖添加量为8％,果汁具有色泽美观、甜酸可口和风味独特等特点。但对最佳配方产品进行冻藏试验,发现产品在冻藏期问褐变程度增大,香气变淡,口感略微变差。     

STORAGE STABILITY OF A STIMULANT COCONUT WATER-CASHEW APPLE JUICE BEVERAGE

Besides flavor, appearance and overall impression, food consumers seek foods rich in nutrients. Fruits are a rich source of nutrients and minerals, and fruit juices are a popular way of consuming them. Development of new products, where two or more kinds of fruit juices are blended to obtain a product that combines the nutritional value of both fruits, which present a different and pleasant taste, has been encouraged by the food industry and has been well accepted by consumers. In this work, the storage stability of a coconut water‐cashew apple juice (87.5:12.5 v/v) beverage was evaluated. Caffeine addition (100 mg/L) conferred stimulating properties to the blend. The physicochemical, microbiological and sensory stability of this blended beverage was evaluated during 6 months. The results showed that the beverage presented good stability for all parameters that were analyzed except for vitamin C, which presented a loss of 58% from the initial content.     

PINEAPPLE JUICE CONCENTRATED BY OSMOTIC EVAPORATION1

Pasteurized pineapple juice was concentrated by osmotic evaporation to produce a 51 d?Brix concentrate that was reconstituted to single strength juice for evaluation. Headspace gas chromatography (HSGC) showed that the concentrate retained an average of 62% of the volatile components present in the initial juice. A sensory panel preferred initial juice over reconstituted concentrate, and noted a decrease in desirable flavor top notes as well as development of some processed flavor in the concentrate. Similar HSGC analysis of four other commercial juice samples showed a wide range of quantitative values for volatile components, with the initial juice being similar to the weakest of these commercial juices. Analysis of concentrated juice extracts permitted identification of additional less‐volatile components not monitored directly by HSGC of the juice. Relatively low levels of these components were also present in the initial juice. Although this nonthermally produced concentrate retains more volatile components than when traditional thermal processing methods are used, addition of aqueous aroma to the concentrate may be required for satisfactory flavor.     

Fortification of set yogurt with passion fruit juice: Effects on fermentation kinetics,physicochemical properties,and functionality

With the purpose of developing an alternative set yogurt with high consumer acceptability, passion fruit juice, at levels that varied from 0 to 10%, was incorporated into set yogurt, and the effects on the fermentation kinetics, physicochemical properties, and functionality of set yogurt were evaluated. The results showed that the addition of passion fruit juice was simultaneously propitious for milk acidification in earlier fermentation stages and reduced the fermentation rate at later stages of fermentation. The phenolic compounds and pectin in passion fruit juice interacted with caseins to form soluble complexes, enhancing the gel strength of set yogurts by 7.5%. The aroma and flavor of the set yogurt was improved as well. However, with the addition of 10% passion fruit juice, the gel structure was destroyed, and the quality of the set yogurt was very degraded. More importantly, the addition of passion fruit juice increased the polyphenol content and significantly enhanced the antioxidant activity of the set yogurt. This investigation demonstrated the feasibility of fabricating passion fruit juice-enriched set yogurt and its superior quality compared with the corresponding normal product.     

百香果全果与果汁发酵酒滋味成分及香气成分对比

目的：提升百香果酒品质。方法：以百香果全果和果汁为原料酿制百香果酒,分别测定其有机酸、氨基酸和挥发性化合物含量,并结合电子舌试验结果评价百香果酒风味成分。结果：2种百香果发酵酒中主要有机酸为酒石酸、柠檬酸、乳酸和苹果酸,但全果酒的前3种有机酸含量均显著高于果汁酒中的（P<0.05）,全果酒和果汁酒中含量最多的有机酸分别为酒石酸（27.20 mg/mL）和柠檬酸（12.49 mg/mL）;除半胱氨酸未检出外,全果酒和果汁酒中16种游离氨基酸总含量分别为88.16,68.88 mg/100 g,且全果酒中4类呈味氨基酸含量高于果汁酒;电子舌测试发现,2种百香果发酵酒中咸味信号强度差异性最大,且全果酒中的鲜味、咸味最强,酸味、涩味和甜味最弱;HS-SPME-GC-MS共检出179种香气成分,全果酒中挥发性风味化合物种类比果汁酒多4种,但其萜烯类物质含量和种类分别比果汁酒的多1,3倍。结论：相比于果汁酒,新型百香果全果酒整体风味（鲜味、咸味、萜烯类物质等）较突出,提升了百香果资源的综合利用度。