Determination of Gibberellin A3 residue in fruit samples by liquid chromatography–tandem mass spectrometry

A fast, simple, low cost, and high throughput method has been developed for the determination of Gibberellin A3 residue in fruit samples (apple, orange, peach, pear and grape). Analysis is performed by LC–MS/MS operated in the multiple reaction monitoring (MRM) mode, acquiring two specific precursor-product ion transitions per target compound. The method has been validated showing good linearity and selectivity. Limits of quantification (LOQs) were 10 μg kg⁻¹ for apple, orange, peach, pear and grape samples. The average recoveries, measured at three concentration levels (10, 20 and 200 μg kg⁻¹) were in the range 77.8–96.2% for the compound tested with relative standard deviations below 13.7%. The proposed method is rapid, simple and could be utilised for the routine analysis of Gibberellin A3 in fruit samples.     

百香果—苹果复合发酵型乳饮料工艺优化及抗氧化性研究

目的:制作一款新型百香果、苹果发酵乳饮料。方法:以百香果、苹果和纯牛奶为原料,以感官评价、蛋白质含量为指标,利用模糊数学评价法,考察苹果汁添加量、百香果汁添加量、蔗糖添加量、发酵时间、菌种接种量对百香果—苹果风味发酵乳感官品质的影响,并对发酵乳的抗氧化性及各项指标进行检测。结果:百香果—苹果风味发酵乳的最佳配方为纯牛奶82.59%,百香果汁2.35%,苹果汁8.00%,蔗糖7.00%,增稠剂0.06%,菌种0.002 06%,发酵时间6.50 h。此条件下,发酵乳的感官评分为8.99,蛋白质含量为3.12 g/100 g,其理化指标和卫生指标均符合相关国标要求。抗氧化性结果表明,百香果—苹果乳饮料发酵后对DPPH自由基和羟自由基的清除率均比发酵前有所提升,分别为77.7%,45.7%。结论:最佳配方下得到的发酵乳呈淡黄色,具有良好的组织状态,无乳清析出,不分层,具有百香果和苹果的清香和发酵乳特有风味,酸甜比例合适。     

LC with Evaporative Light-Scattering Detection for Quantitative Analysis of Organic Acids in Juices

In this work, a performing LC method with evaporative light-scattering detector was described for the analysis of tartaric, malic, ascorbic, citric and succinic acids in fruit juices. The method was optimized and validated in comparison with LC-UV, in terms of accuracy, LODs, LOQs and precision. The successive application to ACE, orange, pear, peach, mulberry and apple juices allowed separation and quantitative determination of organic acids in about 20 min just diluting and filtering the sample before LC determination. In the analysed juices, citric, malic and ascorbic acids were always present, and in all the samples, citric acid was the prevailing acid followed by malic acid except for peach and apple juices where an opposite trend was found. Tartaric and succinic acids were detected at lower concentrations and more rarely, except for peach juices, all containing tartaric acid, and ACE and orange juices, all containing succinic acid.     

中国果蔬饮料生产与市场

中国果蔬饮料业与整个饮料业几乎是同时发展，但发展缓慢，一直处于对市场的不断摸索阶段。经过近二十年的曲折发展，开始成熟，在苹果，橙，桃，杏，山楂，芒果，菠萝、西番莲、胡萝卜、黑加仑、草莓、树莓等果蔬饮料的加工上形成了一定的基础或优势，制定了部分产品检测标准，2001年全国果蔬饮料产量为146万吨，比上年增长了49．87％，成为增幅最大加工，全方位提高质量管理，进一步提高出口产品质量，拓宽市场，是中国果蔬饮料业需迫切解决的问题和发展方向。     

苹果-绿茶复合饮料的研制

以苹果和绿茶为主要原料,采用单因素和正交试验优化苹果-绿茶复合饮料的制作工艺,并进行质量评价。研究结果表明:苹果绿茶复合饮料的最佳配方为:苹果汁与茶汁体积比为25∶75、柠檬酸添加量0.15%、蔗糖添加量8%,食盐的添加量0.04%。在最佳条件下得到的苹果绿茶复合饮料产品为黄绿色,澄清度高、酸甜适口、果香和茶香风味兼具,其检验结果符合GB/T 21733-2008《茶饮料》标准要求。     

复合果汁饮料的生产工艺研究

研究了苹果汁、香蕉汁复合饮料的生产技术条件,并对影响复合饮料稳定性的稳定剂进行了探讨.结果表明,12.5%的苹果汁、18.75%的香蕉汁、蔗糖7%、柠檬酸0.10%、蜂蜜6%为最佳原料配方;添加0.06%黄原胶 0.04%海藻酸钠 0.10% CMC-Na构成的复合稳定剂可以达到较理想的稳定效果.该工艺生产的复合饮料具有与新鲜香蕉果肉相似的香气、色泽,饮料质地均匀,口感滑爽.     

八种水果多酚的定量分析与抗氧化活性研究

本文对比研究了8种水果的果皮、果肉、果汁及全果中维生素C与总酚含量,采用高效液相色谱法测定其多酚种类及含量,并评价其抗氧化活性。8种水果Vc含量从高到低,依次为:番石榴脐橙菠萝=木瓜青苹果=皇冠梨=金桔=芒果;总酚含量最高的水果为芒果;从8种水果中共鉴定出16种多酚类化合物,以绿原酸、儿茶素、表儿茶素、芦丁、杨梅酮和根皮苷含量较高。根据8种水果全果中多酚物质种类与含量,分为4类:(1)脐橙;(2)芒果;(3)金桔;(4)青苹果、皇冠梨、番石榴、菠萝和木瓜;DPPH自由基清除能力从强到弱,依次为芒果番石榴青苹果皇冠梨=金桔=脐橙=菠萝=木瓜;氧自由基吸收能力从强到弱,依次为脐橙番石榴皇冠梨=芒果青苹果=金桔=菠萝=木瓜。本研究可为水果精深加工及功能性食品开发提供理论指导。     

Stability of enterocin AS-48 in fruit and vegetable juices

Enterocin AS-48 is a candidate bacteriocin for food biopreservation. Before addressing application of AS-48 to vegetable-based foods, the interaction between AS-48 and vegetable food components and the stability of AS-48 were studied. Enterocin AS-48 had variable interactions with fruit and vegetable juices, with complete, partial, or negligible loss of activity. For some juices, loss of activity was ameliorated by increasing the bacteriocin concentration, diluting the juice, or applying a heat pretreatment. In juices obtained from cabbage, cauliflower, lettuce, green beans, celery, and avocado, AS-48 was very stable for the first 24 to 48 h of storage under refrigeration, and decay of activity was markedly influenced by storage temperature. In fresh-made fruit juices (orange, apple, grapefruit, pear, pineapple, and kiwi) and juice mixtures, AS-48 was very stable for at least 15 days at 4 degrees C, and bacteriocin activity was still detectable after 30 days of storage. Gradual and variable loss of activity occurred in juices stored at 15 and 28 degrees C; inactivation was faster at higher temperatures. In commercial fruit juices (orange, apple, peach, and pineapple) stored at 4 degrees C, the bacteriocin was completely stable for up to 120 days, and over 60% of initial activity was still present in juices stored at 15 degrees C for the same period. Commercial fruit juices stored at 28 degrees C for 120 days retained between 31.5% (apple) and 67.71% (peach) of their initial bacteriocin activity. Solutions of AS-48 in sterile distilled water were stable (120 days at 4 to 28 degrees C). Limited loss of activity was observed after mixing AS-48 with some food-grade dyes and thickening agents. Enterocin AS-48 added to lettuce juice incubated at 15 degrees C reduced viable counts of Listeria monocytogenes CECT 4032 and Bacillus cereus LWL1 to below detection limits and markedly reduced viable counts of Staphylococcus aureus CECT 976.     

Incidence of patulin in fruits and fruit juices marketed in Campinas, Brazil

One hundred and eleven samples of processed fruit juices (apple, grape, pineapple, papaya, guava, banana and mango) and 38 samples of sound fruits (apple, papaya, mango, pear and peach) produced and marketed in Brazil, were analysed for patulin by HPLC. Only one out of 30 samples of apple juice was found positive at 17 mug/l. Patulin was not detected in the other foodstuffs. It was found in 14 samples of spoiled fruit samples of apple (150-267 mug/kg), pear (134-245 mug/ kg) and peach (92-174 mug/kg). Confirmation of the identity of patulin was based on the UV spectrum obtained by the HPLC diode array detector, compared with thatof standard patulin, TLC developed by several solvent systems and sprayed with 3-methyl-2-benzothiazolinone hydrazone , and by acetylation with acetic anhydride.     

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     

温控辅助离子液体分散液液微萃取-高效液相色谱检测果汁中杀菌剂残留

建立温控辅助离子液体分散液液微萃取结合高效液相色谱-二极管阵列检测器法检测果汁中7 种杀菌剂农药残留的新方法。对影响萃取效果的因素萃取剂和分散剂类型及体积、溶解温度、萃取时间和离心时间进行优化。在优化后的方法条件下,7 种杀菌剂富集倍数可达64～101;方法检出限在4.3～13.0 μg/L之间;在0.02、0.05 mg/L和0.10 mg/L三个水平下加标,果汁（苹果汁、梨汁、葡萄汁、桃汁和橙汁）的平均加标回收率在70.0%～116.2%范围内,相对标准偏差均小于9.8%,能满足多种果汁中杀菌剂农药多残留检测的要求。     

Consumer acceptance of natural sweeteners in protein beverages

Protein beverage consumption by Americans has increased in recent years. Coupled with this increased consumption is an interest in natural sweeteners. The objective of this study was to evaluate the sensory properties of naturally sweetened ready-to-mix (RTM) whey protein beverages using 3 temporal methods and to formulate a natural noncaloric sweetener blend that could be added to RTM protein beverages to provide sweetness while still appealing in flavor to consumers. Iso-sweet concentrations of sweeteners (sucralose, sucrose, fructose, stevia, monk fruit) in RTM vanilla whey protein beverages (25 g of protein/360 mL of water) were established using magnitude estimation scaling and 2-alternative forced-choice testing. Temporal sensory profiling was then conducted on each beverage by a trained panel using time intensity, temporal dominance of sensations, and temporal check-all-that-apply. These findings were used to formulate natural sweetener blends that closely matched the temporality of sucrose-sweetened RTM vanilla protein beverages for consumer testing. One sugar-free blend (25% stevia/75% monk fruit) and 1 reduced-sugar blend (25% stevia/25% monk fruit/50% fructose) were selected for consumer testing (n = 150 consumers) in addition to 3 control RTM beverages containing sucralose, stevia, or monk fruit. Two distinct consumer clusters were identified. The label-conscious segment of consumers preferred beverages sweetened with natural blends when primed. The flavor-driven segment of consumers conceptually preferred naturally sweetened beverages but preferred sucralose-sweetened beverages when primed. An all-natural label claim was most preferred across all consumers. Application of these findings to commercially produced RTM protein beverages aids in the development of naturally sweetened protein beverages with reduced calories and desirable sensory properties and highlights the importance of label claims to consumers overall but to a label-conscious segment of consumers in particular.     

Changes in quality attributes of pulsed light and thermally treated mixed fruit beverages during refrigerated storage (4 °C) condition

The effect of batch pulsed light (PL) irradiation (3000 J cm⁻²) on the shelf-life of the beverage blend comprising apple ber (Indian jujube), carambola (star fruit), and black table grapes was investigated. The equivalent thermally treated beverage (90 °C|5 min) exhibited greater stability from microbial and enzymatic spoilage but retained 27% less antioxidants and 14% less vitamin C than PL-treated juice. Thermally and PL-treated blends possessed sensory scores of 5.8 and 7.2, respectively. The beverage's microbial shelf-life (population ≤ 6-log₁₀ cfu/mL) was extended to 45 days at 4 °C after the PL treatment. The PL exposure did not alter the pH and soluble solids during storage. The PL-treated juice, after 45 days, was placed on par with the freshly prepared juice by the sensory panel. The PL-treated juice preserved 61% more antioxidants, 38.8% more phenolics, and 68.2% more vitamin C than the thermally pasteurized beverage after 45 days of refrigerated storage.Industrial relevanceWhile the fruit processing industry demands microbial safety and enzymatic stability, today's consumer demands juices of high nutritional quality. This study utilizes under-explored fruits like apple ber (Indian jujube) and carambola (star fruit) to make a shelf-stable mixed fruit beverage. This study will help the industry understand the potential of PL treatment in accomplishing microbial safety, enzymatic stability, and nutritional quality, along with the utilization of under-explored fruits.     

Consumer perception of d'Anjou pear classified by dry matter at harvest using near-infrared spectroscopy

Dry matter is increasingly recognised as a reliable indicator of fruit quality and consumer acceptance for numerous commodities. To establish dry matter as an at-harvest metric predictive of post-storage and ripening consumer acceptance in pear, cv. d'Anjou fruits were segregated into low (<13%), moderate (13–15.99%) and high (≥16%) predicted dry matter classifications at harvest using near-infrared spectroscopy and evaluated by untrained consumer panels following cold storage and ripening. Consumers significantly favoured higher dry matter fruits over lower dry matter fruits in terms of perceived firmness, crunchiness, juiciness, sweetness, flavour and overall liking. Consumers were willing to pay premium prices for higher dry matter fruits at an estimated $0.20/lb above average retail prices. Sorting fruit by dry matter at harvest via near-infrared spectroscopy may overcome issues of variation in fruit maturity and quality to produce more consistent consumer experiences in pears following post-storage ripening.     

苹果玫瑰复合果醋饮料配方优化及营养成分测定

为开发苹果玫瑰复合果醋饮料新产品,采用L₉(34)正交实验进行配方优化,对优化配方产品进行理化指标、微生物指标及氨基酸、单体酚、矿物质等营养成分测定分析。结果显示:苹果玫瑰复合果醋饮料的最佳调配比例为:饮料用苹果醋8 mL/100 mL,玫瑰提取液20 mL/100 mL,蔗糖5 g/100 mL,浓缩苹果汁3 g/100 mL。产品理化指标、微生物指标符合国家标准要求。与单一苹果醋饮料相比,复合果醋饮料中含氨基酸16种,总量达到441.47 μg/mL,必需氨基酸总量为273.35 μg/mL,占总氨基酸含量的61.92%;单体酚总含量达266.97 μg/mL,物质浓度提高164倍。此结论可为复合果醋的开发研究提供理论依据。     

特色蟠桃西瓜苹果醋饮料的研究

文中介绍了苹果醋的酿制方法及最佳工艺条件，并以苹果醋为酸味剂，辅以蟠桃汁，西瓜汁，苹果汁，蜂密等，研制出集营养，保健，风味于一体的果醋果汁饮料。     

Utilization of cereal and fruit fibres in low fat dry fermented sausages

The effect of addition of cereal and fruit dietary fibres on the sensory properties of reduced-fat, dry fermented sausages was studied. Dry fermented sausages with 6 and 10% pork backfat were manufactured, with addition of cereal (wheat and oat) and fruit (peach, apple and orange) dietary fibres, at 1.5 and 3% concentrations. The energy value reduction of the final products was close to 35% and their final fibre contents, after ripening, were 2 and 4%, respectively. The ripening process was monitored by physico-chemical and microbiological analysis. Sensory properties were analyzed using triangular and hedonic tests and, a texture profile analysis was carried out. A correlation principal component analysis was performed. The results showed that the sensory and textural properties of batches with 3% dietary fibre were the worst, due to their hardness and cohesiveness. The best results were obtained with sausages containing 10% pork backfat and 1.5% fruit fibre especially those with orange fibre, which gave organoleptic characteristics similar to conventional high fat products. Thus, reduced fat sausages fortified with dietary fibre can be obtained with an acceptable sensory profile.     

甘肃河北两地皇冠梨果实品质比较研究

目的为了解甘肃省皇冠梨的品质特点,对甘肃武威、河北赵县两地皇冠梨、雪花梨果实品质进行分析。方法在甘肃武威、河北赵县等地采集梨果样品80个,测定其品质指标并进行对比分析。结果对于不同的梨品种,皇冠梨和雪花梨的可溶性固形物、葡萄糖、蔗糖等指标差异不显著,但雪花梨的直径、单果重量、硬度等物理指标均显著大于皇冠梨,而果糖、总糖、可滴定酸则显著小于皇冠梨。对于同样的皇冠梨品种,河北赵县皇冠梨的可溶性固形物显著大于甘肃武威市。而对于果实单果重量、直径、硬度、水分、葡萄糖、果糖、蔗糖、总糖、可滴定酸、糖酸比等指标,甘肃皇冠梨和河北皇冠梨并无显著性差异。结论梨的品种和产地均对其品质有影响,与皇冠梨优势产区河北相比,甘肃武威市凉州区的皇冠梨也具有较好的品质。     

Effects of apple and pear varieties and pH on patulin accumulation by Penicillium expansum

BACKGROUND: Accumulation of patulin in apples and pears and subsequently in their by‐products is caused mostly by Penicillium expansum which causes blue mould. Fruit pH and other parameters are sometimes characteristic of a certain variety and thus the use of particular varieties might affect patulin content in the final products. The aim of this study was to evaluate the influence of fruit variety and pH on patulin accumulation. Patulin accumulation in both apple and pear juices at different pH and also in different apple varieties (Golden, Gala and Fuji) and pear varieties (Blanquilla and Conference) was assessed. RESULTS: The pH of juices significantly influenced patulin accumulation, especially in apple juice in which the highest amounts of patulin were detected at pH 3.5. In fruits, the pH values of the substrate were determinant only under cold storage. Thus, Golden apples, which presented a lower pH, accumulated more patulin at 1 °C. However, this trend was not observed at other temperatures in which varieties with higher amounts of organic acids (Golden and Fuji apples) accumulated most patulin. In the pear varieties, significant differences in pH did not lead to significant differences in patulin accumulation. CONCLUSION: Although pH influences patulin accumulation, other factors such as organic acid content may play an important role. Concerning the apple and pear varieties we studied, it seems that rather than variety, other parameters like pH or acidic content may be more important. These parameters vary significantly depending on the degree of ripeness of the fruit. Gala apple, which is used in Spanish juice production, was the only variety that accumulated dramatically higher amounts of patulin. Copyright © 2008 Society of Chemical Industry     

苹果梨果醋饮料的研制 苹果梨果醋饮料的研制

以苹果梨为原料,经过酒精发酵、醋酸发酵和调配等工艺,研制出苹果梨果醋饮料。通过正交试验确定酒精发酵的工艺条件为：发酵时间6d、发酵温度22℃、发酵液pH4.5;醋酸发酵的工艺条件为：pH4.5,发酵温度30℃、发酵时间5d、醋酸菌接种量8%;果醋饮料的配方为：果醋原液添加量12%、果醋液含糖量12%、食盐添加量0.5%。