橙汁中挥发性风味成分分析的研究进展

对橙汁的挥发性风味成分分析的研究进展作了简要概述.其中主要包括挥发性风味成分的定性定量以及香气感官阈值分析,以及采用多元统计方法对风味成分进行分析,为橙汁的生产以及品质判别提供参考.     

壳聚糖协同次氯酸盐对北碚447锦橙贮藏品质的影响

为探讨壳聚糖协同次氯酸盐对北碚447锦橙贮藏品质的影响,用壳聚糖、壳聚糖协同次氯酸钠、壳聚糖协 同次氯酸钙涂膜处理北碚447锦橙,每5 d测定1 次果实贮藏期间果肉中可溶性固形物、总糖、总酸质量分数和VC、 总黄酮、总酚含量等品质指标。结果表明：壳聚糖具有良好的果品品质保持作用,能较好地保持果实VC、总酚含 量以及总糖质量分数;同时,壳聚糖与次氯酸盐协同涂膜对北碚447锦橙品质保持作用明显优于单独使用壳聚糖, 其中0.01 g/mL壳聚糖＋200 mg/L Ca(ClO)2处理效果最显著,有效地延缓了贮藏期间果实品质的下降。说明壳聚糖协 同次氯酸钙能够有效提高北碚447锦橙的贮藏品质和延长其贮藏期。     

Inoculated fermentation of orange juice (Citrus sinensis L.) for production of a citric fruit spirit

The yeast Saccharomyces cerevisiae UFLA CA1174 was evaluated for its potential to produce an orange spirit, as a possible alternative to reduce waste and increase income to citrus farmers. The sugar concentration of the orange juice was adjusted to 16ºBrix and the pH to 4.5. The orange juice was inoculated at approximately 7 log CFU/mL, and the fermentation was performed at room temperature until ºBrix stabilization. The yeast used showed high values for the conversion factors of the substrates into ethanol (Y_p/s 0.50 g/g), the volumetric productivity of ethanol (Q_p 1.78 g/L/h), the biomass productivity (P_x 58.47 g/g) and the fermentation efficiency (E_f 97.83%). The sugars were converted quickly, and a high ethanol concentration (58.13 g/L) was achieved after 24 h of fermentation. The orange wine was distilled in a copper alembic, and the head, heart and tail fractions were collected. The orange spirit produced (heart fraction) had high concentrations of acetaldehyde, ethyl acetate, isoamyl alcohol and 2‐phenylethanol. The results showed that orange juice could be a good substrate for fermentation and distillation, and the sensory analysis performed revealed that the produced beverage had good acceptance by the tasters. Copyright © 2013 The Institute of Brewing & Distilling     

基于顶空-气相色谱-离子迁移谱法的酸橙枳实与甜橙枳实挥发性化学成分表征及鉴别研究

目的 对酸橙枳实与甜橙枳实的挥发性化学成分进行表征以甄别酸橙枳实与甜橙枳实,及鉴别两者与混伪品。方法 采用顶空-气相色谱-离子迁移法(HS-GC-IMS)对酸橙枳实、甜橙枳实、枳实混伪品中的挥发性成分进行分析,筛选特征性的挥发性物质,分别建立酸橙枳实、甜橙枳实的特征性GC-IMS指纹图谱,OPLS-DA法用于验证筛选结果的合理性。结果 基于HS-GC-IMS法共检测到174个峰,并对其中133个峰进行了定性分析,其中41个化合物为首次在枳实中鉴定并报道。筛选得到酸橙特征性挥发性化合物共12个,甜橙枳实特征性挥发性化合物共8个,分别绘制酸橙枳实与甜橙枳实特征性GC-IMS指纹图谱,结合OPLS-DA结果可明显区分酸橙枳实与甜橙枳实、酸橙枳实与混伪品、甜橙枳实与混伪品。结论 所建立的HS-GC-IMS特征性指纹图谱能够实现酸橙枳实与甜橙枳实的甄别以及两者与混伪品的鉴别,能够体现酸橙枳实与甜橙枳实的挥发性物质特征。     

阿克苏灰枣营养及挥发性成分分析

以新疆阿克苏地区新鲜灰枣为试材,采用HPLC、GC/MS等方法对其营养成分及香气成分进行了分析。结果表明:新疆阿克苏地区灰枣水分含量低,总糖含量高,含有丰富的VC、cAMP及必需氨基酸,营养价值高;采用GC-MS技术共鉴定出40种化合物,其主要成分为酯类、烷烃类、醛酮类和醇类。     

Obtaining fruit segments from a traditional orange variety (Citrus sinensis (L.) Osbeck cv. Sangrina) by enzymatic peeling

A process for obtaining fruit segments from a traditional orange of Sangrina variety by enzymatic peeling was optimized. Enzymatic peeling was carried out by fruit infusion under vacuum conditions in a commercial preparation of pectinases and cellulases (Peelzym II). For the optimization of vacuum conditions, the potential enzymatic saturation of albedo was determined. To obtain a final product with good quality, it was necessary to prove the effectiveness of different concentration of Peelzym II for the degradation of the fruit albedo and also the incubation time of the fruits with the enzymatic solution. The best condition to obtain Sangrina segments by enzymatic peeling was 1 ml L⁻¹ of Peelzym II applied at 67 kPa with two vacuum pulses of 2 min and a subsequent period of 40 min in the enzymatic solution at atmospheric pressure. The reuse of the enzyme preparation in an industrial peeling process was also studied. Results show that it is possible to reuse the enzymatic preparation in an industrial peeling process, although a 30% decrease in the pectinase activity occurred after four peeling cycles.     

锦橙皮膳食纤维抗氧化活性研究

目的:提取锦橙皮膳食纤维,研究其对O2-·、·OH、DPPH·三种自由基的清除作用。方法:采用复合酶法对膳食纤维进行提取,采用邻苯三酚自氧化法和Fronton反应对清除O2-·、·OH、DPPH·的效果进行了研究。结果:对O2-.清除率最高为46.28%,对.OH的IC50为3.27mg/mL,对DPPH.的IC50为5.66mg/mL。综上所述,锦橙皮膳食纤维对三种自由基都具有一定的清除作用。     

顶空固相微萃取-气相色谱-质谱法分析脐橙中挥发性成分

目的 探究脐橙果皮和果肉中挥发性成分的种类、相对含量及其风味的差异。方法 将脐橙洗净后切分为果皮及果肉部分, 经粉碎后, 通过顶空固相微萃取(headspace solid phase microextraction, HS-SPME)技术分别富集果皮和果肉的挥发性成分, 再经气相色谱-质谱法(gas chromatography-mass spectrometry, GC-MS)分析其挥发性成分的种类及相对含量, 同时计算各物质的相对气味活度值(relative odor activity value, ROAV)。结果 脐橙中鉴定出烯烃类、醛类、醇类、酮类、酯类和酸类等挥发性成分共82种, 果皮中有59种, 果肉中有51种, 两者共有成分28种, 其中果皮特有挥发性成分31种, 果肉23种; 对果皮风味起关键作用和修饰作用的挥发性成分分别有20种和7种, 果肉分别有9种和7种。脐橙果皮和果肉中相对含量最高的成分均为D-柠檬烯, 分别达到43.97%和41.25%, 果皮次主要成分为芳樟醇, 含量为5.38%, 果肉次主要成分为巴伦烯亚橘烯, 含量为18.50%; 对果皮风味贡献最高的物质为芳樟醇, 主要提供麻香、青香和花香, 对果肉贡献最高的物质为β-紫罗酮, 主要提供花香; 此外果皮和果肉的木调香和清香差异不大, 但果皮的果香、花香、甜香和脂香更加丰富。结论 脐橙果皮和果肉中挥发性成分的种类和含量差异较大, 且造成其关键香气的物质有明显区别。     

柚皮苷酶对琯溪蜜柚果汁脱苦效果工艺优化

以琯溪蜜柚果汁为对象,研究在不同条件下柚皮苷酶对蜜柚果汁的脱苦效果。采用HPLC 测定柚皮苷含量,通过单因素试验分别考察加酶量、温度、酶解时间及pH 值对柚皮苷酶酶解反应的影响,在单因素试验基础上以柚皮苷脱除率为指标进行正交试验,确定最佳工艺条件：酶解温度60℃,酶活7.4U/mL 柚汁,酶解时间100min,pH3.6。在此条件下琯溪蜜柚果汁的柚皮苷脱除率达97% 以上。     

沙田柚不同组织部位酚类物质组成及其抗氧化活性研究

摘 要：目的 揭示沙田柚不同部位酚类物质组成和抗氧化活性的差异。方法 提取沙田柚油胞层、白皮层、囊衣和籽中游离酚和结合酚,测定其总酚、总黄酮含量,单体酚组成和抗氧化活性,并采用皮尔森相关性分析确定酚类物质含量与抗氧化活性之间的相关性。结果 沙田柚各部位酚类物质主要以游离酚为主,其总酚、总黄酮含量变幅分别为2.01~13.28 mg GAE/g DW和3.79~15.2 mg RE/g DW,油胞层和白皮层总酚、总黄酮含量均高于囊衣和籽。从沙田柚各部位鉴定出柚皮苷、橙皮素、甜橙黄酮、对羟基苯甲酸、对香豆酸和阿魏酸共6个单体酚,柚皮苷是各部位中最主要的黄酮类化合物且以白皮层中含量最高。沙田柚各部位铁离子还原能力(ferric reducing antioxidant power,FRAP)和氧自由基吸收能力(oxygen radical absorbance capacity, ORAC)变幅分别为7.6336~69.26 mmol TE/g DW和116.9~625.111.69~62.51 μmol TE/g DW,甜橙黄酮是各部位发挥FRAP活性的重要成分,而柚皮苷是各部位发挥ORAC活性的重要成分。结论 沙田柚副产物,尤其是果皮(油胞层和白皮层),是天然酚类物质的来源。     

Discriminant and principal component analyses to classify commercial orange juices based on relative amounts of volatile juice constituents†

Pasteurised orange juices and two types of commercial orange juice from frozen concentrate were differentiated based on the combined levels of 15–25 volatile constituents monitored in each of 44 juice samples. Multivariate analysis programs were used to calculate discriminant and principal component analyses and to display the results graphically. Since this group of samples was part of a nutritional database study, other parameters were included in an effort to improve discrimination of the types of juice samples monitored. Addition of °Brix and acid values improved the separation by principal component analysis of the three types of juice studied. Discriminant analysis provided better separation of juice types than did principal component analysis.     

橙汁的果汁含量测定及与其6种特征指标相关性的比较

测定了19个橙汁样品的果汁含量,并比较了GB/T16771-1997《橙、柑、桔汁及其饮料中果汁含量的测定》中所规定的6个特征指标(钾、总磷、氨基酸态氮、L-脯氨酸、D-异柠檬酸、总黄酮)含量与果汁含量的相关性。结果表明,6个特征指标的含量和果汁含量都具有不同程度的相关性,其中钾含量与果汁含量相关性最大,相关系数达0.6873;氨基酸态氮含量与果汁含量相关性最小,相关系数为0.3768,但均未达到显著相关水平。     

Characteristics of immobilised β‐glucosidase and its effect on bound volatile compounds in orange juice

In this study, bound volatile compounds were isolated and extracted with Amberlite XAD‐2 resin and then hydrolysed by free or immobilised β‐glucosidase. The released bound volatiles were analysed by GC‐MS. In addition, the optimisation of immobilisation method on sodium alginate and the characteristics of immobilised β‐glucosidase were studied. The results showed that crosslinking‐entrapment was the best method. The optimal conditions of this method were as follows: sodium alginate concentration 3.5%, glutaraldehyde concentration 1%, crosslinking time 3 h, immobilisation time 2 h and CaCl₂ concentration 3%. The optimum temperature for β‐glucosidase (65 °C) was decreased by 10 °C after immobilisation, while the optimum pH values for free and immobilised β‐glucosidase were both at pH 5.0. The K_m values of free and immobilised β‐glucosidase were 14.89 and 0.59 m , respectively. In total, thirteen and six bound volatile compounds were detected in orange juice hydrolysed by free and immobilised β‐glucosidase, including benzenic compounds, terpenic compounds, hydroxy esters, C₁₃‐norisoprenoids and alcohols.     

基于气相色谱-离子迁移谱法构建不同产地沙田柚挥发性物质指纹图谱

为建立一种快速、准确地鉴别沙田柚产地及品质的方法,本文采用顶空气相-离子迁移谱(Head Space-Gas Chromatography-Ion Mobility Spectrometry, HS-GC-IMS)对广东梅县和广西容县产的沙田柚果皮及汁胞的挥发性物质进行了分析,构建了不同产地沙田柚挥发性物质的指纹图谱,比较了不同产地沙田柚的特征挥发物之间的差异及其变化。结果表明,沙田柚汁胞中挥发性有机物的种类,如柠檬烯、芳樟醇、蒎烯等主要香气成分的含量均明显少于果皮。不同产地沙田柚含有的特征挥发性物质的种类及其含量存在差异,通过将果皮或者汁胞的特征挥发物进行PCA分析,均可对广西和广东的柚果进行区分。本研究表明,基于GC-IMS技术结合数据可视化的相似度对比和化学计量学方法,不同产地沙田柚的柚皮挥发物可得到快速、准确地区分,为沙田柚的产地区分、溯源和品质评价提供了一种新的分析方法。     

Radical scavenging activity and phenolic compounds in persimmon (Diospyros kaki L. cv. Mopan)

ABSTRACT:  The Mopan persimmon ( Diospyros kaki L. cv. Mopan) is the major cultivar of astringent persimmon in northern China. This study investigates the radical scavenging activity against ABTS and DPPH radical, and the content of total and individual phenolics (catechin, epicatechin, epigallocatechin, chlorogenic acid, caffeic acid, and gallic acid) with apple, grape, and tomato as controls. The radical scavenging activities against ABTS and DPPH radicals of the Mopan persimmon are 23.575 and 22.597 μm trolox eq/g f.w., respectively. These findings suggest that the Mopan persimmon's antioxidant activity is significantly ( P < 0.05) stronger than that of reference materials. The Mopan persimmon showed the highest content of total phenolics among the 4 materials tested. Significant correlations ( R ²= 0.993, P < 0.05, ABTS radical; R ²= 0.980, P < 0.05, DPPH radical) are found between the total phenolics and the radical scavenging activities. The total content of these 6 kinds of phenolics (catechin, epicatechin, epigallocatechin, chlorogenic acid, caffeic acid, and gallic acid) is significantly correlated ( R ²= 0.831, P < 0.05, ABTS radical; R ²= 0.745, P < 0.05, DPPH radical) with the individual radical scavenging activity of the 4 materials, although the total content of the 6 phenolics accounts for no more than 20% of the total phenolics in the Mopan persimmon. Gallic acid exhibits the strongest antioxidant activity in all 6 kinds of phenolics and its content is the largest in the Mopan persimmon, presumably being responsible for its much higher antioxidant activity as compared to apple, grape, and tomato.     

杀菌贮藏过程中橙汁功能成分降解规律的研究进展

橙汁中富含维生素C、类胡萝卜素和类黄酮等功能成分,具有抗氧化、抗癌、抗炎症、抗过敏以及抗菌等作用。在橙汁的杀菌、贮藏过程中,这些功能成分会发生降解。综述了维生素C、类胡萝卜素和类黄酮等功能成分在杀菌和贮藏过程中的降解规律,以期对橙汁中功能成分的保持和货架期的平衡提供帮助。     

Determination of phenolic composition and antioxidant capacity of blood orange juices obtained from cvs. Moro and Sanguinello (Citrus sinensis (L.) Osbeck) grown in Turkey

The phenolic compounds and antioxidant capacities of orange juices obtained from cvs. Moro and Sanguinello (Citrus sinensis (L.) Osbeck) were determined. A high-performance liquid chromatographic method coupled with diode-array detection was used to identify and quantify phenolic compounds of the orange juices. A total of 18 phenolic compounds were identified and quantified in Moro and Sanguinello orange juices, including hydroxybenzoic acids (2), hydroxycinnamic acids (5), flavanones (5), and anthocyanins (6). It was observed that total phenolic content of Moro juice was higher than that of Sanguinello juice. Ferulic acid was the most dominant hydroxycinnamic acid and cyanidin 3-(6″-malonyl glucoside) and cyanidin 3-glucoside were the most dominant anthocyanins in both cultivars. Antioxidant activities of orange juices were measured using the DPPH^· (2,2-diphenyl-1-picrylhydrazyl) method. According to DPPH^· assays, the antioxidant capacity of Moro juice was found to be higher than that of Sanguinello juice.