橄榄油掺假鉴别技术研究进展

本文简要介绍橄榄油掺假的现状,从常规理化检测法、色谱法、光谱法、核磁等方面对目前橄榄油掺假检测的国内外研究进展作一综述,并对橄榄油掺假检测技术的研究趋势进行展望。     

便携式激光拉曼光谱法快速鉴别橄榄油掺假

目的采用便携式激光拉曼光谱仪,建立激光拉曼光谱对橄榄油进行快速鉴别的方法。方法对橄榄油样品进行光谱扫描及基线校正后,以1440 cm-1作为参考波数,对拉曼光谱数据进行归一化处理。结果对80余份橄榄油样品进行统计分析,发现75%的样品在1265 cm-1的拉曼光谱强度值低于540。特级初榨橄榄油中掺加果渣油,会使1265 cm-1和1650 cm-1的特征峰增强,1525 cm-1处的精细结构变小直至消失。结论拉曼光谱具有便捷、快速、无损分析的特点,可作为橄榄油真伪鉴别在线初步筛查的工具。     

油脂同步荧光光谱检测及橄榄油掺假鉴别

采用同步荧光光谱仪,在激发波长250~720 nm,波长间隔Δλ=15 nm时,采集20种食用植物油和掺杂的特级初榨橄榄油的荧光光谱图,分析比较了各种植物油脂的同步荧光光谱图。结果表明,同步荧光光谱法能够将特级初榨橄榄油与其他17种植物油明显地区分开来。在橄榄油掺杂鉴别中,其中14种植物油掺兑量在1%的情况下,同步荧光光谱图与特级初榨橄榄油有着明显的差异。同步荧光光谱法对橄榄油掺假鉴别,无需复杂的样品前处理,本方法简便、快速、灵敏,适合快速筛查。     

蜡含量法鉴别初榨橄榄油的方法研究

研究了蜡含量法鉴别(特级和中级)初榨橄榄油的方法。采用色谱分离技术,通过柱色谱,洗脱出橄榄油中的蜡组分,再进行气相色谱分析,用内标法测得C40酯至C46酯总的蜡含量。结果表明:该方法C40酯检出限为0.106μg/mL,线性范围为0.001 06～0.106 mg/mL,加标回收率为98.8%～107.1%,试验过程中相对标准偏差(RSD)分别为3.7%和0.8%。该方法具有重复性好,回收率高等特点。通过测定橄榄油中蜡的含量,可用于鉴别(特级和中级)初榨橄榄油。     

橄榄油的质量分级检测技术研究进展

橄榄油是地中海饮食的特点之一,具有极高的营养价值。按照加工工艺橄榄油分为初榨橄榄油和精炼橄榄油。初榨橄榄油的品质较好营养价值较高,因此价格较为昂贵。精炼橄榄油由于品质较差,价格较低。橄榄油的质量分级与经济价值直接相关,已成为目前橄榄油研究的热点。掺伪、造假者的主要目标是特级初榨橄榄油,所以该产品标准的检测十分重要。但由于掺入的食用油在脂肪酸组成等方面与橄榄油非常接近,因此识别起来十分困难。为了规范橄榄油市场,维护消费者的合法权益,研究者采用了多种检测方法来对初榨橄榄油和精炼橄榄油进行鉴别。本研究从标志性成分、模式识别和组学技术3个角度对橄榄油的质量分级检测技术的最新进展情况进行了综述,并对橄榄油的质量分级检测技术的研究方向进行了展望。     

三维荧光光谱法快速检测橄榄油中掺假廉价油

目的 建立三维荧光光谱结合机器学习快速检测橄榄油中掺假廉价油的方法。方法 采集橄榄油及掺入大豆油、玉米油、棕榈油三种不同浓度梯度油的荧光光谱数据,利用标准差标准化（standardscaler）、标准正态变换（standard normal variate,SNV）、归一化（normalize）三种光谱预处理方法,基于K近邻(K-nearest neighbor,KNN)、随机森林(random forest,RF)、支持向量机(support vector machine,SVM)、偏最小二乘法(partial least squares,PLS)和卷积神经网络(convolutional neural network,CNN) 5种机器学习方法,构建5种橄榄油定量掺假模型。结果 在定性模型中,基于PLS算法构建的模型效果最好,对3种掺假橄榄油的准确率为79%~97%,其中,在鉴定掺假大豆油的橄榄油中正确率高达97%。在构建的掺假油定量模型中,Standardscaler预处理结合RF算法,构建的定量模型最优,Rc2、Rp2、RMSEC、RMSEP最高,分别为1.00、0.99、0.01、0.02。结论 构建橄榄油掺假3种油的定性定量模型,并建立一种快速、实时、低成本的橄榄油掺假检测方法,能够准确判断是否掺入廉价油,并量化掺假程度,提供更全面的橄榄油质量评估。     

采用PCR-CE-SSCP技术快速筛查梅花鹿产品的鹿种真伪

梅花鹿副产品是重要的保健品原料,但市场中造假掺假商业欺诈行为屡屡发生,损坏消费者利益的同时给产业的发展带来负面影响。目前基因检测技术在食品药品物种鉴定领域得到广泛应用,但针对不同鹿种的真伪检测报道不多。研究采用的PCR-CE-SSCP技术突破了单纯PCR方法对引物探针体系的要求,仅通过一对引物便可检测到梅花鹿、马鹿、麋鹿等不同的品种,方法特异性强,重现性好,灵敏度高,很适合市场快速筛查。     

基于近红外光谱的橄榄油中玉米油掺杂量检测

利用近红外光谱和模式识别技术建立了橄榄油中掺杂玉米油的快速鉴别方法。对191个橄榄油样本及混合油样本(玉米油和橄榄油)进行近红外光谱扫描,并对近红外光谱进行一阶导数和平滑处理,利用主成分分析法(PCA)对数据进行降维,通过前三个主成分的载荷图确定了相关性较大的特征波段(7520~6927cm-1、6270~5440cm-1和4970~4400cm-1),分别在3个波段内利用偏最小二乘回归(PLS)方法建立了玉米油含量的预测模型。结果表明在6270~5440cm-1波段内,因子数为7,建立的模型精密度和稳定性最好,在玉米油质量分数为0.5%~100%的范围内,校正集样本和检验集样本的R2均能达到0.9999,标准偏差在0.126~0.139之间。因此,利用近红外光谱可以实现橄榄油品质的快速无损分析,以合频波段(6270~5440cm-1)为建模区域可以得到更好的预测效果。     

基于近红外光谱的橄榄油中玉米油掺杂量检测

利用近红外光谱和模式识别技术建立了橄榄油中掺杂玉米油的快速鉴别方法。对191个橄榄油样本及混合油样本（玉米油和橄榄油）进行近红外光谱扫描,并对近红外光谱进行一阶导数和平滑处理,利用主成分分析法（PCA）对数据进行降维,通过前三个主成分的载荷图确定了相关性较大的特征波段（7520⁶927cm-1、6270⁵440cm-1和4970⁴400cm-1）,分别在3个波段内利用偏最小二乘回归（PLS）方法建立了玉米油含量的预测模型。结果表明在6270⁵440cm-1波段内,因子数为7,建立的模型精密度和稳定性最好,在玉米油质量分数为0.5%¹00%的范围内,校正集样本和检验集样本的R2均能达到0.9999,标准偏差在0.126⁰.139之间。因此,利用近红外光谱可以实现橄榄油品质的快速无损分析,以合频波段（6270⁵440cm-1）为建模区域可以得到更好的预测效果。      

意大利推出检验假橄榄油新方法

地中海饮食有益健康,特级初榨橄榄油受热捧,然而一些商家以次级橄榄油混充,牟取高额利润。对此意大利波隆那大学推出一项可检测假油品的新方法。     

橄榄油在中式菜点制作中的运用

橄榄油在地中海沿岸国家有着几千年的食用历史。研究表明,长期食用一定量的橄榄油,可有效降低罹患溃疡性肠炎、心脏病等疾病的风险。由于受到人们的饮食习惯、认识等因素影响,橄榄油在我国的菜肴制作中还没有得到广泛的使用。为了让更多的人们能够享受这种健康食用油,针对中式菜肴的制作特点及中国人的饮食、口味习惯,研究了橄榄油的合理运用方法。     

Proteins in Olive Fruit and Oil

This paper is a comprehensive review grouping the information on the extraction, characterization, and quantitation of olive and olive oil proteins and providing a practical guide about these proteins. Most characterized olive proteins are located in the fruit, mainly in the seed, where different oleosins and storage proteins have been found. Unlike the seed, the olive pulp contains a lower protein content having been described a polypeptide of 4.6 kDa and a thaumain-like protein. Other important proteins studied in olive fruits have been enzymes which could play important roles in olives characteristics. Part of these proteins is transferred from the fruit to the oil during the manufacturing process of olive oil. In fact, the same polypeptide of 4.6 kDa found in the pulp has been described in the olive oil and, additionally, the presence of other proteins and enzymes have also been described. Protein profiles have recently been proposed as an interesting strategy for the varietal classification of olive fruits and oils. Nevertheless, there is still a lot of knowledge without being explored requiring new studies focused on the determination and characterization of these proteins.     

亚临界萃取回收橄榄果渣油的工艺研究

以1,1,1,2-四氟乙烷作萃取溶剂,利用亚临界萃取技术,考察了提取橄榄果渣油提取回收最佳实验条件.采取单因素和三因素三水平正交实验,研究了不同原料粒度、萃取温度和时间对提取率的影响.结果表明当原料粒度为60目,温度为30℃,时间为45 min时萃取效果最好,提取率为93.75％.     

橄榄油对再制奶油干酪品质的影响

以奶油干酪为基料,研究不同比例橄榄油替代黄油在再制奶油干酪中的应用。测定干酪的质构、色度、油脂析出性及感官评定,并进行比较分析。实验结果表明,25%替代水平的干酪在质地和色度方面都与对照组无显著性差异(P>0.05);在油脂析出性和感官评分方面,添加25%橄榄油的干酪均优于对照组。综上,2 5%替代水平的干酪样品与对照组在各项指标上相似度最高,是最合适的替代比例。     

橄榄油加工工艺及品质控制的探讨

研究了橄榄油加工新工艺 ,对橄榄油的质量控制进行了深入探讨 ,出油效率平均达84 7% ,产品质量完全达到国内和国际特级初制橄榄油标准 ,并具有良好的稳定性。该工艺技术成熟、可靠 ,有良好的推广应用价值     

Substituting Olive Oil for Pork Backfat Affects Quality of Low-Fat Frankfurters

Low-fat frankfurters (10% fat), formulated for 10%, 12% and 14% protein, were made with olive oil. Compared to control (27.6% all animal fat, 10.9% protein) they had similar flavor, lower (P<0.05) TBA values and reduced (44.7–47.6%) caloric content, but had lower (P<0.05) processing yield (5.5–6.5%) and overall palatability. Among low-fat treatments, samples with 12% protein had better quality characteristics. The 12% protein frankfurters compared to the control (exccpl for palatability), had similar (P>0.05) sensory attributes and higher (P<0.05) skin strength and improved texture. The treatment with 10% protein had undesirable color and was very soft. That with 14% protein had the same (P>0.05) red color as the control but higher (P<0.05) firmness, skin strength and textural traits and lower (P<0.05) juiciness.     

The Historical Development and Nutritional Importance of Olive and Olive Oil Constituted an Important Part of the Mediterranean Diet

The olive tree (Olea europaea) is widely cultivated for the production of both oil and table olives and very significant because of its economic value. Olive and olive oil, a traditional food product with thousands of years of history, are the essential components of the Mediterranean diet and are largely consumed in the world. Beside of their economical contribution to national economy, these are an important food in terms of their nutritional value. Olive and olive oil may have a role in the prevention of coronary heart disease and certain cancers because of their high levels of monosaturated fatty acids and phenolic compounds. In addition, olives (Olea europaea L.) and olive oils provide a rich source of natural antioxidants. These make them both fairly stable against auto-oxidation and suitable for human health. The aim of this paper is to define the historical development and nutritional importance of olive and olive oil constituted an important part of the Mediterranean diet.     

Authentication of Extra Virgin Olive Oil from Sesame Oil Using FTIR Spectroscopy and Gas Chromatography

The presence of sesame oil in extra virgin olive oil has been investigated using Fourier transform infrared spectroscopy and gas chromatography. Frequencies of 1207–1018, 1517–1222, and 3050–2927 cm^?1 were chosen for quantification of sesame oil in extra virgin olive oil. Using Fourier transform infrared normal spectra coupled with a partial least square model, the root mean standard error of calibration and root mean standard error of prediction obtained were relatively low, i.e., 0.331 and 1.01% (vol/vol), respectively. Using fatty acid profiles as determined by gas chromatography, the levels of palmitic and oleic acids were decreased linearly with R² of 0.969 and 0.934, meanwhile the levels of stearic and linoleic acids were increased with R² of 0.930 and 0.959, respectively, with the increasing levels of sesame oil. From level 10% sesame oil (vol/vol), all these fatty acids are significantly different (p < 0.05).     

Sensory Authentication of European Extra-Virgin Olive Oil Varieties by Mathematical Procedures

Multidimensional scaling and a fuzzy filter qualifier were used together for authenticating and characterising four olive oil varieties—Picual and Arbequina (Spain), Coratina (Italy) and Koroneiki (Greece)—representative of the most important producer countries. Twenty four samples were evaluated by five panels of different nationalities—British, Greek, Italian and Spanish—these being representatives of traditional and potential consumers of virgin olive oil. Each sample was initially characterised by 74 sensory attributes. The paper analyses the most outstanding attributes and their evaluation intensities that characterise the varieties and gives the sensory profiling of each variety. Green attributes characterise Koroneiki variety, Arbequina variety is characterised by sweet–fruity sensory attributes, the bitter–pungent sensory attributes can identify Coratina while a strong fruity odour explains the sensory characteristics of Picual variety.