基于有机酸HPLC指纹图谱的甜樱桃果汁掺假鉴定

根据甜樱桃果汁中有机酸的高效液相色谱（high performance liquid chromatography,HPLC）分析方法,利用“中药色谱指纹图谱相似度评价系统（V2.0）”软件建立甜樱桃果汁的有机酸HPLC指纹图谱,并通过相似度评价、主成分分析和聚类分析,对模拟在甜樱桃果汁中添加低价果汁（梨汁、苹果汁、杏汁和桃汁）和外源柠檬酸等掺假方式进行鉴别。结果表明：42 个甜樱桃果汁的有机酸指纹图谱与对照指纹图谱的相似度均在0.948以上,不同品种、不同采收时间的甜樱桃果汁的指纹图谱具有很好的一致性,甜樱桃果汁中添加其他果汁或柠檬酸可导致相似度降低;结合主成分分析和聚类分析等模式识别方法,可以实现对甜樱桃果汁与掺假低价果汁（梨汁、苹果汁、杏汁和桃汁）及外源柠檬酸样品的区分,而且掺假量越大,识别效果越好,而相似度评价仅能识别掺假量较高的样品。甜樱桃果汁有机酸HPLC指纹图谱结合化学计量学分析,对于掺假甜樱桃果汁具有较好的区分效果,可用于甜樱桃果汁掺假鉴定和质量控制。     

蓝莓汁有机酸高效液相色谱指纹图谱构建及其在掺假鉴定中的应用

根据蓝莓汁中有机酸的高效液相色谱(high performance liquid chromatography,HPLC)分析方法,利用"中药色谱指纹图谱相似度评价系统(V2.0)"建立蓝莓汁的有机酸HPLC指纹图谱,并通过相似度评价、主成分分析和聚类分析,对模拟掺假低价果汁(梨汁、苹果汁、杏汁和桃汁)和外源柠檬酸的蓝莓汁进行鉴别。结果表明:10个蓝莓汁样品的有机酸HPLC指纹图谱之间相似度均在0.950以上,与对照指纹图谱的相似度均在0.978以上,不同品种、不同产地的蓝莓果汁的指纹图谱具有很好的一致性,蓝莓果汁中添加其他果汁或柠檬酸可导致相似度降低;结合主成分分析和聚类分析等模式识别方法,可以实现对蓝莓汁与掺假低价果汁(梨汁、苹果汁、杏汁和桃汁)及外源柠檬酸样品的区分,而且掺假量越大,识别效果越好,而相似度评价仅能识别掺加量较高的样品。有机酸HPLC指纹图谱结合化学计量学分析,对于掺假蓝莓果汁具有较好的区分效果,可用于蓝莓汁掺假鉴定和质量控制。     

桑葚果实不同发育期品质测定及其相关性分析

本研究对湛江地区7个桑葚品种青果期、转色期、成熟期三个时期桑葚果的单果重、可溶性固形物、可滴定酸含量及糖和有机酸组成和含量进行了测定,并进行了相关性分析。结果表明,在成熟过程中桑葚果实的可溶性固形物和糖含量呈增加的趋势,而酸则呈降低的趋势;在桑葚果实品种中检测出柠檬酸、苹果酸、奎宁酸、琥珀酸、酒石酸、酮戊二酸、抗坏血酸、草酸共8种有机酸,其中柠檬酸的含量最高,其在不同品种不同发育期含量为44.84%~80.86%,其次为奎宁酸和苹果酸;果糖和葡萄糖是桑葚重要的糖组成,其含量在成熟期的台湾长果桑的含量分别达到57.79 mg/g和66.72 mg/g,并且只有在台湾长果桑中检测到蔗糖;通过相关性分析,可滴定酸与可溶性固形物、果糖、葡萄糖、果重呈负相关,且可溶性固形物、果糖含量、葡萄糖含量三者之间呈极正相关。     

蓝莓果实外观与糖、酸、酚组成特征

以21个蓝莓品种果实为试材,观测外观特点,检测可溶性糖、有机酸营养组成,旨在为育种、栽培、鲜食品种选择提供依据。结果表明,蓝莓果型指数均小于1,大多呈不同程度扁球形,少数近球形和饼形;单果重为0.52 g～2.63 g,其中‘达柔’超过2.5 g,是少有的大型果;果实多呈蓝色且表面附着果粉,‘粉红佳人’为稀有的红色少果粉品种,‘黑珍珠’是罕见的黑色无果粉种质;果实越大果形越扁含水量越高。果实含有果糖、葡萄糖2种可溶性糖和草酸、奎尼酸、苹果酸、莽草酸、柠檬酸5种有机酸以及绿原酸、儿茶素2种酚类物质,3类物质含量依次递减、差异显著。同一品种中两种糖含量相当且葡萄糖含量（48.81 mg/kg）略高于果糖含量（44.41 mg/kg）,果糖甜度（7 771）显著高于葡萄糖甜度（3 661）,属于己糖积累型果实,果糖、葡萄糖、总糖含量及甜度变化趋势和幅度极为相似,果糖含量越高,葡萄糖含量越高,果实越甜,‘喜来’、‘日出’是优良的高糖品种。柠檬酸含量最高（6.31 mg/kg）,占总酸的76.52%,显著高于其它有机酸,属于柠檬酸优势型果品,不同品种间奎尼酸含量差异巨大,相差1 000余倍,‘北...     

基于原料与果汁品质的蓝莓果实加工性能评价

以‘蓝金’、‘瑞卡’、‘N5’等12个辽南露地栽培蓝莓品种果实为试材,通过果实外观、营养品质及加工性能指标的观测与分析,筛选加工适宜品种。结果表明,蓝莓果实以蓝色为主,呈不同程度扁球形,表面附着果粉,单果重0.95~2.63 g;含水量>80%,果越大,含水量越高,果型越扁,果实中均含有果糖、葡萄糖、草酸、奎尼酸、苹果酸、莽草酸和柠檬酸,果糖与葡萄糖含量相当,柠檬酸含量显著高于其它有机酸（P<0.05）,属于已糖积累型、柠檬酸优势型果品。供试品种果实中均含有钾、镁、钙、铁、锰、锌和铜元素,含量依次递减,钾含量最高（5786 mg?kg?1）,极显著高于其它元素（P<0.01）,‘达柔’果实中钾含量（7400 mg?kg?1）最高。不同品种果实不添加果胶酶处理出汁率差异极大（变异系数达60.42%）,添加果胶酶处理出汁率差异很小（变异系数仅3.88%）,添加果胶酶处理出汁率及果汁可溶性糖、可滴定酸含量明显提升,添加果胶酶处理能够提高果汁产率和质量。果实中果糖和葡萄糖含量越高,果汁中可溶性糖含量越高（相关系数为0.96和0.98）;果实中柠檬酸和奎尼酸含量越高,果汁中可滴定酸含量越高（相关系数为0.81和0.71）。‘日出’、‘蓝金’和‘北卫’3个品种可溶性糖（>90 mg?g?1）、有机酸含量（>10 mg?g?1）和出汁率（>74.6%）均较高,是较好的加工品种。综上,‘日出’、‘蓝金’和‘北卫’3个品种果实营养丰富、出汁率高,是加工的理想原料。     

HPLC法测定10个引自北美蓝莓品种果实中的糖酸组分及含量

采用HPLC法对10个引自北美的蓝莓品种果实中糖、酸组分及含量进行测定。结果表明,蓝莓果实中的可溶性糖以果糖和葡萄糖为主,果糖含量在18.916~73.899 mg/g之间,葡萄糖含量在19.194~79.521 mg/g之间;有机酸组分有草酸、奎宁酸、苹果酸、维生素C和柠檬酸,其中以柠檬酸为主,含量在1.174~15.069 mg/g之间,草酸最低,含量在0.018~0.046 mg/g之间。不同品种蓝莓果实的糖、酸含量存在明显差异,其中果糖和葡萄糖含量最高的品种是北空,柠檬酸含量最高的品种是伊丽莎白。糖酸比和甜酸比是影响果实风味的重要因素,10个蓝莓品种果实的糖酸比在2.342~27.488之间,甜酸比在285.953~3393.854之间,表现为北空芝妮圣云友谊美登北陆蓝光爱国者布丽吉塔伊丽莎白。     

海南省人心果营养价值综合评价

本文以海南省市售人心果为研究对象,参照食品安全国家标准,测定蛋白质、糖、酸、水分和矿物元素含量等多项指标,对其进行综合评价。结果表明,海南人心果中含有丰富的蛋白质、糖和有机酸,各成分含量均存在显著性差异（P <0.05）;果肉可溶性糖主要由葡萄糖、果糖、蔗糖组成,其中果糖含量略高于葡萄糖和蔗糖;果肉有机酸主要由丁二酸、柠檬酸、苹果酸、乳酸和己二酸组成,不同品种人心果不同有机酸之间存在显著性差异（P <0.05）;K、Ca、Na、Mg、P、Fe、Zn、Mn、Cu、Se是人心果中主要的矿物元素,不同品种人心果不同部位矿物元素含量差异显著（P <0.05）。研究表明,海南人心果具有较高的营养价值,开发利用前景广阔。     

不同芒果品种果实可溶性糖组分含量特征分析

分析研究芒果主产区（海南、广西）的3种主要芒果品种（台农、金煌、贵妃）的可溶性糖组分含量与差异。以3种芒果主栽品种为材料,对果实中可溶性固形物（total soluble solid,TSS）、总糖、甜度值进行测定;利用高效液相色谱法对成熟期的芒果果实中的可溶性糖及含量进行分析测定。结果表明：芒果果实可溶性糖主要由蔗糖、果糖、葡萄糖组成,其中蔗糖含量最高,均值为79.07 mg/g FW;台农果实的总糖、甜度值、蔗糖和果糖含量最高,葡萄糖含量最高的是金煌,可溶性固形物含量最低的是贵妃;芒果果实中蔗糖和果糖含量高低表现为台农＞金煌＞贵妃（品种）、海南＞广西（产地）。相关性分析显示,3种可溶性糖中对果实甜度呈正相关的是蔗糖和果糖。聚类分析可将芒果样品分为蔗糖积累型、中间积累型和己糖（葡萄糖和果糖）积累型。     

果啤与果汁组分差异的比较

采用气相色谱和高效液相色谱,分析了市售菠萝果啤、菠萝香精及菠萝果汁的风味成分、有机酸、糖的组成及含量。分析结果表明,果啤中酯类含量相对果汁与香精组成丰富,含量协调;果汁中含量较高的酸(苹果酸与草酸)发酵成果啤后有很大的降低;糖含量中,蔗糖消耗大,而果糖和葡萄糖含量有所升高。     

部分市售果汁果糖含量的快速检测

本文旨在通过检测果糖快速鉴别果汁是否掺假。方法:根据国家标准方法进行果汁样品中果糖的测定。利用班氏试剂快速检测果汁中的还原糖,来辨别真假果汁。结果:果汁中果糖的快速检测结果准确,操作方便。结论:果汁中果糖的快速检测是未来发展的趋势。     

Factors influencing quantities of sugars and organic acids in blackcurrant concentrates

 Use of endogenous non-volatile flavour components, i. e. sugars and organic acids, in fruit juice products is desirable. A study of 133 blackcurrant concentrates from three seasons examined variation in sugars and acids arising from storage of fruit at freezing or sub-ambient temperature, seasonal differences, geographical origin and choice of conventional thermal-evaporative or freeze concentration technology. Compared with freeze concentrates, conventional concentrates had significantly higher contents of total sugars and acids, notably malic acid, and higher fructose/glucose, lower malic/citric acid and similar sugar/acid ratios. Concentrates from frozen fruit generally had smaller amounts of fructose, total sugars and fructose/glucose ratios than those from fresh fruit, as well as less citric, ascorbic and total acids and lower sugar/acid ratios. Principal component analysis of 40 randomly chosen concentrates showed that variance is dominated by differences in fructose, total sugars and ascorbic acid contents and sugar/acid ratios. Geographical origin and concentration technology were major sources of variance but changes in post-production sub-ambient storage could not be excluded. Received: 4 July 1997 /  Revised version: 14 October 1997     

Sugar composition of apple juices

Fifty-one samples from 12 geographic growing regions of Turkey and 3 varieties common for production of apple juice concentrate were processed to apple juice and analysed for their sugar composition. Enzymatic analyses was used to determine soluble sugars of apple juice. Glucose, fructose, sucrose, total sugar concentrations (g/l) and total soluble solids (%) of apple juices were ranged, respectively, as follows: 9.30-32.2, 66.10-96.00, 8.5-55.10, 110.90-164.40, 11.80-18.60. Cultivar significantly influenced the content of all the sugar analysed. Significant differences in fructose and sucrose concentrations have also been found between some growing areas.     

Antioxidant activity and total phenolic,organic acid and sugar content in commercial pomegranate juices

Pomegranate fruit and pomegranate juices (PJs) have taken great attention for their health benefits in the last years. The purpose of this study is to analyse the antioxidant activities, along with the organic acid and sugar contents of pomegranate juices sold in the Turkish markets. In the present study, we evaluated total phenolics (TPs), free radical scavenging capacity by 2,2-diphenyl-1-picrylhydrazyl (DPPH), and ferric reducing capacity of seven commercial PJs. Organic acid and sugar contents of juices were determined by capillary zone electrophoresis. The results showed that commercial pomegranate juices had markedly high total phenolic contents and antioxidant capacity. Fructose (F) and glucose (G) were found as the major sugars. The major acids were citric and malic. From the F/G ratio, organic acid profiles, TPs, and antioxidant capacity values, a possible adulteration was detected in one of the juices.     

Sugars and acids of strawberry varieties

The sugar and acid compositions of six strawberry (Fragaria×ananassa Duch.) varieties from 1997 and 1998, grown in different conditions, 26 samples in all, were investigated by GC as trimethylsilyl derivatives. The major sugars were glucose (1.89–4.52?g/100?ml), fructose (2.14–4.14?g/100?ml) and sucrose (0.90–3.87?g/100?ml), the major acids being citric (0.73–1.58?g/100?ml) and malic (0.22–0.69?g/100?ml). Total sugar content (glucose+fructose+sucrose) varied from 5.35?g/100?ml to 10.96?g/100?ml in accordance with soluble solids (°Brix). The correlation between them showed a linear regression y=0.873x-0.420, the percentage of determination of the regression model being 82.1%. Among one variety only, ‘Senga Sengana’, the percentage of the model was 86.9%. No significant differences were found between the strawberries from conventional versus those from organic farms. Contents of sugars and soluble solids were lower in varieties ‘Jonsok’ and ‘Honeoye’ than in ‘Korona’, ‘Bounty’ and ‘Polka’. The concentrations of malic acid were significantly higher in Senga Sengana, Jonsok and Bounty than in other varieties.     

Determination of volatile, phenolic, organic acid and sugar components in a Turkish cv. Dortyol (Citrus sinensis L. Osbeck) orange juice

BACKGROUND: Orange flavour is the results of a natural combination of volatile compounds in a well‐balanced system including sugars, acids and phenolic compounds. This paper reports the results of the first determination of aroma, organic acids, sugars, and phenolic components in Dortyol yerli orange juices. RESULTS: A total of 58 volatile components, including esters (nine), terpenes (19), terpenols (13), aldehydes (two), ketones (three), alcohols (four) and acids (eight) were identified and quantified in Dortyol yerli orange juice by GC‐FID and GC‐MS. Organic acids, sugars and phenolic compositions were also determined by HPLC methods. The major organic acid and sugar found were citric acid and sucrose, respectively. With regard to phenolics, 14 compounds were identified and quantified in the orange juice. CONCLUSION: Terpenes and terpenols were found as the main types of volatile components in Dortyol yerli orange juice. In terms of aroma contribution to orange juice, 12 compounds were prominent based on the odour activity values (OAVs). The highest OAV values were recorded for ethyl butanoate, nootkatone, linalool and DL ‐limonene. When we compare the obtained results of cv. Dortyol orange juice with the other orange juice varieties, the composition of Dortyol orange juice was similar to Valencia and Navel orange juices. Copyright © 2011 Society of Chemical Industry     

Analysis of sugars,organic acids and vitamin C contents of blackberry genotypes from Turkey

The paper reports the composition of some quality characteristics of five blackberry varieties (“C. Thornless”, “Bursa 2”, “Navaho”, “Jumbo” and “Loch Ness”). Main soluble sugar and acid contents of experimental varieties were separated, identified and quantified using high-performance liquid chromatography with photo diode array spectrophotometric and refractive index detection, for organic acids, ascorbic acids and soluble sugars, respectively. According to the results, malic acid was detected as the main organic acid while citric acid was not detected in blackberry fruits. Ascorbic acid content was found very low quantity and also was not detected in all the cultivars. As for the sugars, fructose was found as the most abundant sugar and highly detected in “Navaho”. However, the highest total sugar/malic acid ratio was found in cv. C. Thornless.     

基于品质指标的苹果浊汁品种与产地差异性分析

以来自7?个不同主产区的21?个主栽品种,共41?份苹果鲜果为研究对象,对每个品种鲜榨浊汁的出汁率、浊度、果汁颜色、褐变度、透光率、可溶性固形物、可滴定酸、总酚、糖、有机酸、VC、矿物质、抗氧化性等品质指标进行测定。运用描述性分析、逐步线性判别分析进行数据处理。结果表明：不同品种或不同产地的苹果浊汁,品质差异较大。总体来看,a*值、原始浊度、褐变度、可滴定酸、葡萄糖、蔗糖、苹果酸等指标的变幅均较大,分别为94.07%、70.41%、42.86%、35.26%、42.02%、42.40%、37.69%。对于不同品种的苹果浊汁,由于褐变度、总酚、抗氧化性等色泽品质指标以及糖、酸等营养品质指标间具有较大差异,其分布呈现分散状态。其中新红星品种的褐变度、总酚含量、DPPH自由基清除率等品质指标普遍居高,色泽品质差异最显著。富士品种大部分样品的果糖、葡萄糖、蔗糖、苹果酸等指标含量较高,具有较好的营养品质。然而对于不同产地间的样品,其浊度、可滴定酸、可溶性固形物等加工品质指标具有较大差异,样品分布较为分散。河北省样品的出汁率、原始浊度、可滴定酸等指标普遍较低,加工品质较差。来自山东省不同品种苹果浊汁的样品以及来自不同产地富士苹果浊汁的样品间均具有较大差异,并且分别获得了77.8%和72.7%的判别准确率。以上结果表明,不同产地、不同品种苹果原料制得的苹果浊汁存在较大差异,通过对其品质指标进行差异性分析,可为上游育种与种植产业结构调整提供数据基础;通过判别模型的建立实现品种与产地的识别与预测,可以指导企业对苹果原料进行制汁专用化筛选。     

Influence of the cultivar on the organic acid and sugar composition of potatoes

BACKGROUND: Citric, malic, tartaric, oxalic, ascorbic, aconitic and fumaric acids, and sucrose, fructose and glucose, were determined in ten potato cultivars (Azucena negra, Bonita, Bonita negra, Borralla, Colorada de baga, Mora, Negra, Palmera lagarteada, Peluca blanca and Terrenta) from the Canary Islands in order to differentiate them. The influence of the production zone was also considered. RESULTS: Citric acid and sucrose were the most abundant organic acid and sugar, respectively. There were significant differences in all the analysed sugars and organic acids between the potato cultivars, except for oxalic and malic acids. Differences associated with the production zone were found in the contents of organic acids for some cultivars. Linear discriminant analysis is a useful tool to differentiate the potato samples according to the cultivar and the zone of production. CONCLUSIONS: Seven organic acids (citric, oxalic, malic, tartaric, aconitic, fumaric, and ascorbic acids) were identified and quantified in potatoes. The main sugars (sucrose, glucose and fructose) were also determined. The genetic information of the cultivars determines marked differences in sugars and organic acid contents among the analysed potato cultivars. The soil and climatic conditions affect the organic acid and sugar contents of some potato cultivars. Copyright © 2010 Society of Chemical Industry