Authentication of honey sample via test sample and principal component analysis

The use of principal component analysis (PCA) of large data sets for the authentication of honey samples is illustrated. The procedure uses a predetermined training set of the most characteristic honeys selected by PCA from a large collection of various honeys. The PCA solution of the training set and sample in question, results in a plot indicating honey position and membership to rape, heather, or honeydew honey. The procedure is general and can be applied and extended for authentication of other foodstuffs.     

Physicochemical properties and pollen spectrum of imported and local samples of blossom honey from the Pakistani market

Fifteen samples of different geographical origin including Pakistan were analysed for density, ash, water content, electrical conductivity, total acidity, pH, total solid, hydroxylmethylfurfural (HMF), minerals and trace metals. The physicochemical parameters were found to be within acceptable ranges (specific gravity 1.40–1.46, ash 0.03–0.21%, moisture 15.6–19.2, total solid 78.7–81.4%, free acidity 23.55–58.52 meq kg^?1, conductivity 0.27–0.37 mS cm^?1, pH 3.29–4.05, viscosity 33.4–136.4 poise). However, the analysis of HMF showed that imported samples were either exposed to a high temperature during processing or were overage. Greater attention is required, therefore, in the analysis of HMF and in deciding the shelf life, particularly for the imported samples before marketing. Pollen analysis revealed that all the analysed samples were of a multifloral type. All the data were statistically tested using principal component analysis (PCA) with the aim of characterizing the honeys and identifying the most significant parameters in the analysed samples.     

Geographical discrimination of honeys through antioxidant capacity,mineral content and colour

The assessment of geographical origin of honey is economically important for producers and consumers as every region may present particular quality characteristics. In this study, honeys from the seven different regions of Buenos Aires province (Argentina) were characterised by their antioxidant capacity (DPPH, FRAP), total phenolic content (TPC), mineral composition, colour and ash. Honeys showed significant differences among their antioxidant capacity (DPPH), ash, colour and mineral content (P ≤ 0.05). Besides, a good antioxidant activity and low amounts of Cu and Zn (<1.0–1.5 and 0.7–1.8 mg kg^?1, respectively) were found in the samples. Significant Pearson's correlations (P ≤ 0.05) among the different parameters were found. Moreover, the linear discriminant analysis allowed the classification of honeys in their original groups with a prediction success of 98%. The present results suggest that honeys could be correctly classified by their geographical origin through their TPC, colour, ash and mineral concentrations.     

Determination of some individual phenolic compounds and antioxidant capacity of mead produced from different types of honey

The aim of this study was to promote mead (honey wine) production by testing the appropriateness of different honey varieties which were obtained from the flora of Turkey for the production of mead. Cotton‐Mezda (Gossypium spp.), pine (Pinus spp.) and flower honeys were used in the fermentation studies. Pure culture Saccharomyces cerevisiae yeasts were used in the mead studies. While determining the phenolic contents of meads via HPLC method, five phenolic acids and two flavonoids were used as standards with known antioxidant properties. In addition, total antioxidant activity was analysed in meads using trolox equivalent antioxidant capacity (TEAC). Among the phenolic acids, the most abundant one was protocatechuic acid (75.12–179.03 μg/L) and among flavonoids it was catechin (10.38–125.55 μg/L). It was found out that total phenolic content ranged from 103.56 GAE to 167.89 GAE mg/L. Copyright © 2017 The Institute of Brewing & Distilling     

2个品种不同成熟度油茶果实品质差异比较

为明确油茶果实的最佳采收期,以赣石83-4和赣石447油茶鲜果为原料,测定其不同成熟度下果实品质相关的表型性状、营养物质和种仁油中脂肪酸组成及含量的变化,并采用主成分分析法对2个品种不同成熟度油茶果实品质进行综合评价。结果表明：随着成熟度的增加,2个品种油茶果实的单果质量、含水率总体呈下降趋势,而鲜果出籽率、干籽出仁率则总体呈上升的趋势;赣石83-4种仁含油率在第四成熟度达到最大值(44.16%),而赣石447种仁含油率在第二成熟度达到最大值(48.56%);赣石447和赣石83-4种仁可溶性糖含量随成熟度变化趋势不一致,前者在第四成熟度达到最大值(11.35%),后者在第五成熟度达到最大值(13.05%);2个品种不同成熟度的油茶种仁蛋白质含量较低且总体上较稳定;2个品种油茶种仁油中脂肪酸组成及含量存在差异,随着成熟度的增加,油酸和单不饱和脂肪酸含量持续增加,而亚油酸和多不饱和脂肪酸含量降低,饱和脂肪酸和不饱和脂肪酸含量的变化幅度较小,分别维持在11%和89%左右;主成分分析结果表明,赣石83-4和赣石447的最佳采收期分别在第五成熟度和第四成熟度。综上,赣石83-4和赣石447油茶...     

贵州蓝莓蜜营养成分分析

该文以贵州麻江3个不同产地蓝莓蜜为研究对象,采用国标方法测定氨基酸、维生素和矿物质含量,研究其营养价值.结果显示3个产地蓝莓蜜样品中均检测到14种氨基酸、5种维生素和5种矿物质.蓝莓蜜中氨基酸含量为146.70 mg/100 g～167.00 mg/100 g,以苯丙氨酸、谷氨酸和天冬氨酸为主,其中药效氨基酸占比70....     

不同护色处理的枇杷果酒挥发性风味成分对比

以万州大五星枇杷为研究对象,采用不同的护色工艺酿造枇杷果酒。分别采用液相色相仪、氨基酸自动分析仪与顶空固相微萃取（HS-SPME）结合气相色谱-质谱（GC-MS）联用技术检测不同果酒样品中有机酸、氨基酸及挥发性风味物质,并结合主成分分析（PCA）和聚类分析（CA）对其挥发性风味物质进行分析。结果表明,添加抗坏血酸、柠檬酸结合热处理的护色处理酿造枇杷果酒护色效果最佳,与未经护色处理样品相比,该护色处理有利于增加果酒中有机酸（苹果酸、柠檬酸、丁二酸）、氨基酸（苦味、芳香族及甜味氨基酸）含量;共检出挥发性风味物质38种,其中酯类、醇类、酮类、其他类物质分别增加2种、3种、1种、1种;PCA结果表明,不同枇杷果酒样品中主要挥发性风味物质为辛酸乙酯、乙酸苯乙酯、癸酸乙酯、苯乙醇等,聚类分析将样品聚集为三大类。     

月季花瓣营养成分评价及主成分和聚类分析

为探明不同品种月季花瓣营养成分间的差异和相关性,该研究对河南南阳地区10个不同栽培品种月季花瓣中的基本营养成分进行了测定,并结合化学计量学对各营养成分进行了分析评价.结果表明,所测品种中蛋白质和脂肪的平均含量分别为8.93％、1.28％(质量分数);矿物元素K、Ca、Mg、Na、Fe、Mn、Cu、Zn、Se等的平均含量...     

黑龙江不同产地北苍术中氨基酸的组成特征及营养评价

目的 探究黑龙江不同产地北苍术中氨基酸的组成特征,并对其营养价值进行评价。方法 收集黑龙江5个产地(大兴安岭、齐齐哈尔、哈尔滨、牡丹江和佳木斯)共24批次北苍术,采用氨基酸自动分析仪对其氨基酸的组成与含量进行测定,通过氨基酸比值系数法对其进行营养价值评价,按照氨基酸的含量进行聚类热图分析。结果 24份北苍术中至少含有17种氨基酸,总氨基酸含量介于(2.557±0.053)～(8.093±0.031) g/100 g,其中必需氨基酸、非必需氨基酸、儿童氨基酸、药用氨基酸、支链氨基酸、抗菌氨基酸和伯氨基氨基酸含量分别为(0.586±0.024)～(1.502±0.106)、(1.919±0.064)～(6.653±0.290)、(1.184±0.059)～(3.647±0.145)、(1.516±0.075)～(5.304±0.131)、(0.265±0.005)～(0.694±0.044)、(0.162±0.004)～(0.425±0.036)和(1.751±0.076)～(6.306±0.228) g/100 g;鲜味氨基酸、甜味氨基酸、苦味氨基酸和芳香族氨基酸的含量分别占总氨基酸含量...     

湖南野生酸橙株系的品质分析及评价

搜集了湖南省14个野生酸橙株系,通过与3个果园实生繁殖栽培株系熟果的品质指标包括色度（L^*值、a^*值、b^*值）、出汁率、可溶性固形物、可滴定酸、固酸比、黄酮类物质（芸香柚皮苷、柚皮苷、橙皮苷、新橙皮苷）、抗坏血酸进行比较分析,并对上述12项品质指标进行主成分分析和聚类分析的综合品质评价,结果表明:野生株系之间以及野生与实生株系之间在品质上存在显著性差异。主成分分析得出排名前5的株系包括野生株系‘宜章-Ⅰ’、‘长沙-Ⅰ’和‘衡东-Ⅰ’和实生株系‘湘阴-Ⅰ’和‘湘阴-Ⅱ’。聚类分析将14个酸橙株系聚为3类,其中主成分综合得分在前2位的株系‘宜章-Ⅰ’和‘湘阴-Ⅰ’聚为了一类,得分排名3⁵位的株系‘长沙-Ⅰ’、‘衡东-Ⅰ’和‘湘阴-Ⅱ’聚为了一类,与主成分分析的结果一致。通过综合得分评价筛选出了3个野生株系‘宜章-Ⅰ’、‘长沙-Ⅰ’、‘衡东-Ⅰ’综合品质较好,可作为较理想的加工型酸橙株系进行推广繁殖与驯化栽培。      

冬虫夏草水提物HPLC指纹图谱及模式识别分析

目的:通过建立不同产地冬虫夏草的高效液相色谱(HPLC)指纹图谱,评价不同产地冬虫夏草质量差异,比较冬虫夏草与冬虫夏草菌丝体质量差异,为冬虫夏草药材的质量鉴别提供科学依据。方法:采用HPLC法,以甲醇-0.3%乙酸溶液为流动相进行梯度洗脱,检测波长260 nm,对10批冬虫夏草和9批冬虫夏草菌丝体进行指纹图谱研究。通过相似度评价结合主成分分析、聚类分析对冬虫夏草指纹图谱进行综合评价。结果:建立了冬虫夏草HPLC指纹图谱,标定18个共有峰,指认出其中5个共有峰,分别为胞苷、尿苷、肌苷、鸟苷和腺苷;方法的精密度、稳定性和重复性的峰面积RSD分别小于2.99%、3.04%和3.16%,符合指纹图谱分析要求。10批冬虫夏草相似度均大于0.92;冬虫夏草与冬虫夏草菌丝体相似度为0.563~0.693,通过指纹图谱特征可实现有效区分,表明二者化学成分存在较大差异。主成分分析和聚类分析将样品分为3类,冬虫夏草单独为1类,该结果与相似度分析结果基本一致。结论:建立的HPLC图谱结合主成分分析和聚类分析,可以快速进行冬虫夏草的真伪鉴别,为冬虫夏草质量控制提供理论参考。     

Characterisation of Serbian unifloral honeys according to their physicochemical parameters

The characterisation of three unifloral Serbian honeys (acacia, sunflower and linden) was carried out based on some common physicochemical parameters (water content, electrical conductivity, free acidity, optical rotation and pH). A total of 201 honey samples, collected during the 2009 harvesting season, were analysed. Principal component analysis (PCA) and linear discriminant analysis (LDA) were used to highlight the data structure and to find the relationships between the physicochemical parameters and the botanical origin of honey. The variables that best discriminated the samples were electrical conductivity (ranging from 0.10 to 0.76 mS/cm), free acidity (ranging from 7.80 to 42.70 meq/kg) and pH (ranging from 3.17 to 5.85). LDA resulted in a classification model with a high predictive power, allowing further assessment of unknown samples of the three unifloral honeys. Determination of geographic origin of acacia honey samples based on physicochemical properties and chemometrics was attempted.     

Determination of heavy metals in different honey brands from Iranian markets

A variety of elements are present in honey at different concentrations. Although some of these heavy metals and trace elements are useful nutrition, at higher levels they could cause health problems. In order to achieve confidence about food safety, regular monitoring of food quality is necessary. In this study, heavy metals and trace element contents were determined by inductively coupled plasma atomic emission spectrometer in 10 different honey brands from Iranian markets. All heavy metal contents in these samples were within ranges as reported in literature, except for Hg, Al and As. Compared with recommended daily intakes, it is concluded that heavy metals or trace elements intoxication following honey consumption in Iran is unlikely.     

不同产地库尔勒香梨生育期果实品质变化规律及综合评价

目的 分析库尔勒香梨果实外观品质与营养品质的时空变化规律,比较果实品质的区域差异,对不同产地商品果的品质进行综合评价。方法 采集花后60d~140d内不同产区（新疆库尔勒、阿克苏、甘肃酒泉）的10个果园共计90份库尔勒香梨样品,用常规方法测定单果重、纵径、横径等外观品质指标,通过直接滴定法测定还原糖和总酸的含量,用高效液相色谱法分析果实中的柠檬酸、苹果酸、酒石酸、富马酸、丁二酸和山梨糖醇、果糖、葡萄糖、蔗糖,采用方差分析比较生育期产地的品质差异,通过主成分分析法综合评价果实的品质优劣。结果 库尔勒香梨果实在花后60~140d,随着果实的不断成熟,硬度呈快速下降的趋势,由7.19 N/cm2下降至2.91 N/cm2。还原糖的含量由1.1g/100g上升到7.3g/100g,总酸由3.63g/kg下降到0.71g/kg。成熟期4种糖中果糖、葡萄糖、山梨糖醇占比为99%,5种有机酸中苹果酸和酒石酸占比为96%。果糖∶葡萄糖∶山梨糖醇含量比值由花后60d时的1∶1.5∶7.5上升为花后140d的1∶0.9∶0.6,苹果酸∶酒石酸∶柠檬酸含量比值由花后60d时的1∶0.37∶0.03变化为花后140d的1∶0.27∶0.13,糖酸比由花后60d的24上升到花后140d的174。成熟期三个产地糖类含量无显著差异,横径、果形指数、柠檬酸新疆与甘肃产地存在显著差异（P＜0.05）。主成分分析结果表明,前四个主成分累计方差贡献率为89.14%,果形指数、果糖、横径、山梨糖醇、葡萄糖、苹果酸、总酸可作为库尔勒香梨品质评价的重要指标。结论 库尔勒香梨在花后60d~140d的生育期内,果实中山梨糖醇的比例随着成熟度的增加逐渐降低,果糖和葡萄糖比例显著增加,有机酸以苹果酸和酒石酸为主,呈显著下降趋势,花后140d糖酸比最大,风味最好。在采样果园中库尔勒4个果园的品质最好,酒泉3个果园次之,阿克苏3个果园品质较差。     

基于主成分及聚类分析的不同产地红枣功能成分品质分析

目的 比较不同产地的红枣功能成分品质差异。方法 选取新疆不同产地的12个红枣原料,对其多酚、总糖、总黄酮、皂甙、环磷酸腺苷(cyclic adenosine monophosphate, cAMP)和维生素C含量进行测定,通过主成分分析和聚类分析对红枣功能成分的品质进行综合评价。结果 多酚含量排名前3的红枣产地分别是伊吾县、和田县和沙雅县,总糖含量排名前3的红枣产地分别是伊吾县、若羌县和莎车县,总黄酮含量排名前3的红枣产地分别是伊吾县、巴楚县和沙雅县,皂苷含量排名前3的红枣产地分别是麦盖提县、莎车县和轮台县, cAMP含量排名前3的红枣产地分别是沙雅县、麦盖提县和疏勒县,维生素C含量排名前3的红枣产地分别是疏勒县、图木舒克市和阿拉尔市。红枣功能成分指标评价可简化为4个主成分,累积方差贡献率达到92.359%。根据功能成分的综合得分,功能成分综合品质排名前3的红枣产地是伊吾县、沙雅县、麦盖提县。当欧氏距离为15时, 12个产地红枣按功能成分可以分为三类。结论 基于主成分分析和聚类分析的分析方法简便、科学、有效,可用于分析不同产地红枣品质。     

响应面实验优化红肉蜜柚果酒发酵工艺

为优化红肉蜜柚果酒发酵工艺,以红肉蜜柚果汁为原料,在对发酵温度、二氧化硫添加量、果酒干酵母添加量、发酵时间、初始糖度和初始p H单因素实验基础上,应用Box-behnken中心组合实验设计,并进行响应面分析优化红肉蜜柚果酒发酵工艺。结果表明,红肉蜜柚果酒发酵最佳工艺条件为:发酵温度28℃、二氧化硫添加量61 mg/L、果酒干酵母添加量61 mg/100 m L、发酵时间15 d,在此优化条件下,红肉蜜柚果酒的酒精体积分数为13%,与响应面预测值13.25%拟合性较好,其残留总糖为1 g/L左右、酒呈淡橙红色,澄清透明,气味芳香,酒香浓郁,带有明亮的柚子风味,口感柔和,对实际生产有一定指导意义。      

Investigation of the aroma impact volatiles in Turkish pine honey samples produced in Marmaris,Datça and Fethiye regions by SPME/GC/MS technique

The aroma impact volatiles of twenty‐four pine honey samples produced in Marmaris, Datça and Fethiye regions of Turkey were evaluated by solid phase micro extraction/gas chromatography/mass spectrometry (MS) technique and the results were evaluated by using the analysis of variance and Duncan tests. A total of eight common volatiles nonanal, nonanol, decanal, octanal, 16‐oxosalutaridine, dodecanal, nonadecane and pentadecane were detected in three regions. The total area of the common volatiles were 73.01%, 78.10% and 73.91% in Marmaris, Datça, and Fethiye regions, respectively. There were not significant differences (P < 0.05) between the common volatiles detected in pine honey samples from three different regions. The major contributers to the pine honey aroma seems to be nonanal (aldehyde, citrus, fatty, floral, green, piny), nonanol (green, sweet, oily), decanal (soap, orange peel, tallow), and octanal (fat, soap, lemon, green). Nonanal seems to be the principal volatile component in all samples having average values of 46.82% in Marmaris, 51.67% in Datça and 48.63% in Fethiye regions.     

直立独龙蔓不同高度结果部位对葡萄酒香气物质成分的影响

以宁夏玉泉营农场直立独龙蔓整形方式下酿酒葡萄梅鹿辄、赤霞珠和霞多丽为试验材料,研究不同高度结果部位对葡萄酒香气物质成分及含量的影响。结果表明,梅鹿辄、赤霞珠、霞多丽三个供试品种不同结果部位葡萄酒中香气物质总量均表现为上层结果区＞中层结果区＞下层结果区,其中主要香气物质酯类和醇类的相对含量占比均为上层结果区＞中层结果区＞下层结果区。通过对香气成分进行主成分分析,初步确定了各品种不同高度结果部位葡萄酒特征性香气成分。建议改变宁夏产区整形方式,使结果部位保持在同一高度,以获得香气物质含量一致的优质葡萄酒。