国内初榨橄榄油品质特性研究

以国内种植的油橄榄为原料,研究了油橄榄品种、成熟度以及堆放时间对初榨橄榄油脂肪酸组成、酸值、过氧化值及风味的影响。结果表明：不同品种油橄榄的初榨橄榄油中油酸和亚油酸含量差异较大,油酸含量范围65.85%~80.08%,亚油酸含量范围2.61%~17.18%;初榨橄榄油的酸值随油橄榄成熟度的升高而降低,其中鄂植8号酸值（KOH）从0.35 mg/g下降到0.26 mg/g;紫果的初榨橄榄油过氧化值低于青红果和红果;油橄榄堆放时间延长会使初榨橄榄油的过氧化值略有增加,而酸值的增加程度因品种而异。不同形式的油橄榄初榨橄榄油在风味上均能很好地区分。     

初榨橄榄油在加热过程中品质变化研究

初榨橄榄油营养丰富且具保健价值,研究初榨橄榄油在烹调加热过程中品质的变化具有重要意义。采用仪器分析和化学分析法研究初榨橄榄油在加热过程中品质指标的变化。研究结果表明,初榨橄榄油在180℃加热过程中,脂肪酸值、过氧化值、羰基值、黏度逐渐增加,饱和脂肪酸和反式脂肪酸含量增加,不饱和脂肪酸含量下降。初榨橄榄油在180℃加热300 min时,过氧化值开始超标;加热480 min时,脂肪酸值、羰基值、反式脂肪酸含量仍未超标或超过推荐量。初榨橄榄油在180℃下加热烹调食品不宜超过240 min。如果要延长烹调加热时间,可以适当降低加热温度。该研究为初榨橄榄油在食品中的煎炸及含初榨橄榄油食品的高温处理提供科学参考。     

凉山州4个引进品种初榨橄榄油的品质分析

对凉山州4个引进品种(佛奥、奥托卡、豆果、城固32)初榨橄榄油的酸值、过氧化值、α-生育酚含量、豆甾醇含量和β-谷甾醇含量以及脂肪酸组成进行测定,并采用主成分分析综合评价了凉山州4个引进品种初榨橄榄油的品质。结果表明:4个品种初榨橄榄油的酸值和过氧化值均较低;城固32的α-生育酚含量和β-谷甾醇含量最高,分别为164.48 mg/kg和1 149.59 mg/kg,除奥托卡的豆甾醇含量较低外,其余3个品种差异较小;4个品种初榨橄榄油的脂肪酸组成差异较小,不饱和脂肪酸含量为77.34%~82.17%,饱和脂肪酸含量为17.09%~18.87%。综合评价表明4个品种初榨橄榄油中奥托卡的品质最好。     

初榨橄榄油风味化合物研究进展

阐述了初榨橄榄油风味的主要来源途径即脂氧合酶途径,对影响初榨橄榄油风味特征的若干因素如品种和地理环境,油橄榄果实成熟度,加工工艺,储藏条件等因素进行了讨论和分析.介绍了初榨橄榄油中挥发性化合物的分析检测方法,并且展望了橄榄油风味化合物研究的应用和发展前景.     

四川青川县初榨橄榄油营养成分及油脂特性分析

为摸清四川青川县主栽油橄榄品种初榨橄榄油的脂肪酸组成、营养成分和挥发性物质,利用气相色谱、气质联相色谱对油脂进行检测,结果显示:平均不饱和脂肪酸为82.82%,为豆果83.30%皮削利83.05%鄂植8号82.1%,其中品种间油酸和油酸含量间存在显著差异;平均值维生素E含量为28.78 mg/100 g,为鄂植8号32.7 mg/100 g!皮削利27.5 mg/100 g!豆果24.4mg/100g,品种间α-维生素E存在显著差异;平均值角鲨烯含量为4 512.48 mg/kg,为皮削利6 690.95 mg/kg!鄂植8号4 386.50 mg/kg!豆果2 460.00 mg/kg,品种间角鲨烯存在极显著差异;平均值β-谷甾醇含量为849.00 mg/kg,为鄂植8号1 161.30 mg/kg!皮削利946.35 mg/kg!豆果439.35 mg/kg,品种间β-谷甾醇存在极显著差异。油脂中鉴定出25种挥发性化合物,其中醛类4个,醇类2个,酯类5个,烯烃类7个和萜烯类5个,其他2种;鄂植8号和豆果橄榄油挥发性物质的主要为醛类,占总物质的55.88%和52.58%,皮削利挥发性物质主要为烯烃类物质,占总物质的53.68%。综上所述,青川初榨橄榄油营养物质丰富,挥发性物质独特,香味浓郁,存在明显的地域特征,具有良好的开发价值。     

甘肃武都区5个主栽品种初榨橄榄油的品质分析

以甘肃武都区主栽的5个品种初榨橄榄油(佛奥、莱星、鄂植8、科拉蒂、皮削利)为研究对象,分析了其外观品质、风味特征、酸值、过氧化值、生物活性成分含量和脂肪酸组成。结果表明:5种初榨橄榄油的色泽和风味有一定关系,色泽较深的科拉蒂口味较重,佛奥、皮削利次之,莱星和鄂植8的色泽较浅、口味也较淡;5种初榨橄榄油的酸值(KOH)和过氧化值分别在0.21~0.49 mg/g和4.82~9.65 mmol/kg之间,均符合国家标准要求;5个品种初榨橄榄油中总黄酮和总多酚的含量分别在459.94~708.08μg/g和108.66~257.22μg/g之间,其中科拉蒂的均最高;主要脂肪酸组成及含量为棕榈酸(C16∶0)7.04%~14.31%、棕榈油酸(C16∶1)0.14%~1.27%、硬脂酸(C18∶0)0.98%~1.82%、油酸(C18∶1)74.73%~82.91%、亚油酸(C18∶2)6.77%~9.27%、亚麻酸(C18∶3)0.16%~0.35%,其中科拉蒂的油酸含量最高;5个品种初榨橄榄油的角鲨烯含量在0.07%~0.27%之间。综合分析表明,5个品种初榨橄榄油均具有优良品质,其中科拉蒂的综合品质最佳。     

陇南两种单品种初榨橄榄油的化学性质和脂肪酸组成随成熟度的变化

分析了陇南2个品种初榨橄榄油的化学性质和脂肪酸组成随成熟度增加的变化规律。结果表明：随着成熟度的增加2个品种的鲜果出油率增加且存在显著性差异。初榨橄榄油风味成分中氮氧化合物、含硫以及烷烃类化合物变化幅度较大,通过电子鼻可以区分不同品种不同成熟度的橄榄油。恩帕特雷和科拉蒂的k232、270值最高分别为1.85和1.91、0.18和0.14,多酚、黄酮含量变化范围分别为2.39～4.53和7.47～10.39、0.07～0.40和0.75～2.84 mg/g。氧化稳定时间在第6（6.28 h）和第5(16.71 h)成熟度为最高。酸价的变化范围分别为0.37～1.02和0.19～0.38 mg/g,过氧化值的变化范围分别为2.92～8.32和2.38～5.19 mmol /kg,油酸含量分别为72.36%～77.76%和59.23%～65.73%,亚油酸含量分别为7.70%～11.81%和9.74%～15.86%,SFA含量分别为11.81%～13.15%和14.25%～20.99%,PUFA含量分别为8.34%～12.36%和10.92%～16.84%,MUFA含量为72.69%～78.50%和62.36%～68.20 %。同一品种的MUFA/PUFA、C18:1/C18:2和MUFA含量变化趋势一致,与PUFA呈相反的变化趋势,2个品种之间各种脂肪酸含量差异明显,上述测定指标完全符合GB 23347—2009中特级初榨橄榄油的标准。科拉蒂的出油率、多酚、黄酮、油酸含量和氧化稳定时间明显大于恩帕特雷,而酸价、过氧化值低于后者。综合考虑认为科拉蒂的初榨橄榄油品质优于恩帕特雷,恩帕特雷和科拉蒂分别在第6和第5成熟度的初榨橄榄油品质最好。     

高压脉冲电场处理对初榨橄榄油得率和品质的影响

为开发一种能提高初榨橄榄油(VOO)得率、对品质无不利影响且适用于工业化生产的新工艺,以甘肃陇南产区莱星、鄂植8号品种油橄榄鲜果为原料,采用高压脉冲电场(PEF)处理辅助传统工艺提取VOO,通过与传统提取工艺比较,研究PEF处理对VOO得率、理化性质、总多酚含量和脂肪酸组成及相对含量的影响。结果表明:与传统提取工艺相比,采用PEF处理VOO得率平均增幅为15.38%,果渣含油率平均降幅为22.28%,对VOO的色泽、酸值、过氧化值、总多酚含量和脂肪酸组成及相对含量等总体无显著性影响。研究认为,在VOO传统提取工艺的基础上,鲜果破碎之后增加PEF处理环节,可显著提高VOO得率,而且对VOO品质无不利影响,该技术在VOO工业化生产中有良好的应用潜力。     

我国油橄榄果及初榨橄榄油品质研究

研究了我国8个品种包括鄂植8、城固32、皮削利、莱星、佛奥、阿贝奎纳、皮瓜尔和奇迹油橄榄果及初榨橄榄油的品质。油橄榄果成熟指数介于2.28~6.44,果实纵径和横径分别为15.53~27.18 mm、11.09~19.93 mm,果质量为0.92~5.59 g,果肉率为78.08%~86.82%,含水率为42.39%~63.23%,含油率为15.11%~30.55%。8个品种橄榄油的饱和脂肪酸为14.72%~18.41%,单不饱和脂肪酸和多不饱和脂肪酸质量分数分别为63.93%~80.79%、3.29%~20.03%。橄榄油主要脂肪酸为油酸(62.47%~79.28%)、棕榈酸(11.41%~15.06%)以及亚油酸(2.60%~19.09%)。主要甘油三酯分别为OOO(24.73%~48.24%)、POO(19.25%~27.91%)、LOO(6.63%~21.03%)以及POL+SLL(3.14%~12.99%)。α-生育酚含量为126.18~292.77 mg/kg,β-生育酚与δ-生育酚均不超过10 mg/kg,γ-生育酚分布于8.85~42.50 mg/kg之间。角鲨烯含量为2 709.7~7 856.5 mg/kg;城固32甾醇总量最高,接近3 000 mg/kg。     

西班牙和意大利进口特级初榨橄榄油品质比较

为了系统研究我国主要进口的特级初榨橄榄油性质,比较分析了我国主要进口的8种西班牙和意大利特级初榨橄榄油的脂肪酸组成、酸值、过氧化值及微量成分含量,并对其进行了挥发性成分分析及感官评价。结果表明：西班牙特级初榨橄榄油的C18∶1（77.22%）和C23∶0（0.94%）含量平均值高于意大利样品（分别为72.46%和0.64%）,西班牙特级初榨橄榄油的酸值、过氧化值低于意大利样品;西班牙特级初榨橄榄油中含有γ-生育酚和δ-生育三烯酚,而意大利样品中未检出这两种,且西班牙特级初榨橄榄油中α-生育酚含量平均值（189.58 mg/kg）高于意大利样品（161.26 mg/kg）,角鲨烯含量平均值（6 127.83 mg/kg）远高于意大利样品（4 083.50 mg/kg）,两者甾醇含量差异很小。虽然西班牙特级初榨橄榄油的醛类含量平均值低于意大利样品,但酯类含量更高。感官评价发现,西班牙特级初榨橄榄油的果味、苦味、辣味评分皆高于意大利样品。综上,西班牙特级初榨橄榄油的酸值、过氧化值较低,α-生育酚、角鲨烯含量高于意大利样品,且感官评分较高。     

Influence of the malaxation time and olive ripening stage on oil quality and phenolic compounds of virgin olive oils

The main objective of this study was to evaluate the influence of the malaxation time (Mt) and ripening stage on oil quality and phenolic compounds of Hojiblanca and Picual virgin olive oils. In both varieties of oil, phenolic content and oxidative stability decreased as ripening progressed. The total level of tocopherols diminished by up to 40% as fruit ripened. The compositions of palmitic, stearic, lignoceric, oleic, linoleic and linolenic acids were significantly influenced by the ripening process. The present work shows that an increased Mt promoted the increase of free acidity (up to 13.3%) and tocopherols (up to 11.6%) and negatively affected the oxidative stability and the concentration of phenols. Further research is required to determine ripening stages and malaxation conditions for all olive oil varieties to achieve a satisfactory balance between the improvement of both oil yield and oil quality and composition.     

添加新鲜橄榄叶和复合果胶酶压榨对油橄榄果出油率和初榨橄榄油品质的影响

为提高油橄榄果出油率、改善初榨橄榄油(VOO)品质,以甘肃陇南主栽的成熟度为7的莱星品种油橄榄鲜果为原料,考察压榨过程中新鲜橄榄叶(0、3%、5%)和复合果胶酶(0、0.01%、0.02%)添加量(以油橄榄果质量计)对油橄榄果出油率和VOO色泽、叶绿素含量、基本理化性质、总酚含量、脂肪酸组成及含量的影响。结果表明：添加适量的新鲜橄榄叶可提高出油率及总酚含量,降低酸值,但色泽加深,叶绿素含量和过氧化值升高;添加适量的复合果胶酶在提高出油率的同时,VOO的总酚含量上升,叶绿素含量和过氧化值降低,但酸值升高,色泽加深;压榨过程中添加新鲜橄榄叶和复合果胶酶对VOO脂肪酸组成没有影响,但对油酸、亚油酸、棕榈酸和棕榈烯酸等主要脂肪酸含量有一定影响。在压榨制取VOO时添加适量的新鲜橄榄叶与复合果胶酶可提高出油率,获得富含多酚的VOO。     

Contribution of olive seed to the phenolic profile and related quality parameters of virgin olive oil

BACKGROUND: Conflicting results have been reported about the effect of fruit de‐stoning on the virgin olive oil (VOO) phenolic profile. The aim of the present study was to determine whether olive seed plays any role in the synthesis of this oil phenolic fraction. RESULTS: Increases of around 25% of total phenolic compounds were observed in oils obtained from de‐stoned olive fruits in three main Spanish cultivars. To investigate the involvement of olive seed in determining the phenolic profile of VOO, whole intact olive fruits were added with up to 400% olive stones. Excellent regression coefficients were found in general for the decrease of total phenolic compounds and, particularly, of o‐diphenolics in the resulting oils. On the other hand, it was found that olive seed contains a high level of peroxidase (POX) activity (72.4 U g^?1 FW), accounting for more than 98% of total POX activity in the whole fruit. This activity is able to modify VOO phenolics in vitro, similar to the effect of adding stones during VOO extraction. CONCLUSION: Olive seed plays an important role in determining VOO phenolic profile during the process to obtain an oil that seems to be associated with a high level of POX activity. Copyright © 2007 Society of Chemical Industry     

Optimisation of extra virgin olive oil quality

This study investigated the correlation between total polyphenol content and the stability (ie induction time by Rancimat) of oil samples according to different regions, cultivars, extraction technologies and ripening times of raw material. Results indicate a correlation of oil stability with total polyphenols, (r=0·88), a chemical variable easy to determine. We have set up an oil quality index as a measure of desirability including legal parameters, especially the Council Olive Oil International score (COI Score), stability (phenol content) and process yield into account. The study of the effects of olive ripening and storage prior to processing and olive paste mixing times and temperatures on the quality index using an experimental factorial design (2⁴) were investigated. The process variables selected in the experimental factorial design were studied and the main effects on desirability were identified. Based on this information, the extraction process was optimised for quality index in relation to fruit ripening and olive paste mixing time using a response contour to identify optimal experimental conditions. This innovative procedure shows that process conditions can be optimised as a function of D_tot, evaluated according to scientific determinations. © 1998 SCI.     

Influence of O2 on the quality of virgin olive oil during malaxation

The aim of this work was to investigate the effect of malaxation operating conditions on virgin olive oil quality. Legal, sensory and nutritional parameters of olive oil were evaluated by identifying the role played by enzymes. A comparison was made between oil obtained from a traditional malaxation plant and oil obtained from malaxation equipment (LOM) able to work at low oxygen level and temperature. Research results showed that, during malaxation, oxygen had an effect on both phenolic compounds and fatty acids, mainly favouring enzyme phenomena. Malaxation at a low oxygen level was found to be selective for the formation of both phenolic and C₆ compounds. Oil obtained from malaxation LOM equipment was shown to be richer in both aldehydes such as trans‐2‐hexenal and phenolic compounds than oil obtained from traditional processing. Copyright © 2006 Society of Chemical Industry     

Effect of extra virgin olive oil substitution for fat on quality of pork patty

BACKGROUND: Extra virgin olive oil (EVOO) is well known for its beneficial effects on human health. Thus, the purpose of this study was to investigate the effect of EVOO substitution for backfat on qualities of pork patty to avoid high consumption of animal‐originated fat, because it is closely related to development of cardiovascular disease and obesity. RESULT: Water‐holding capacity was higher in control (lean pork + 10% backfat) and T3 (lean pork + 5% backfat + 5% EVOO + 0.5% isolated soy protein + 0.5% carrageenan + 0.5% maltodextrin) than T1 (lean pork + 5% backfat + 5% EVOO + 0.5% isolated soy protein) and T2 (lean pork + 5% backfat + 5% EVOO + 0.5% isolated soy protein + 0.5% carrageenan). Hardness was higher in EVOO substitution for backfat patty samples than control. In sensory evaluation, the control was significantly higher in overall acceptability compared with EVOO substitution for backfat pork patty samples. CONCLUSION: The physical properties of pork patty made by EVOO substitution for backfat were stable as a commercial pork patty (control). However, sensory evaluation scores were higher in control compared to EVOO‐substituted pork patty samples. Copyright © 2008 Society of Chemical Industry     

Distribution of dimorphic yeast species in commercial extra virgin olive oil

Recent microbiological research has demonstrated the presence of a rich microflora mainly composed of yeasts in the suspended fraction of freshly produced olive oil. Some of the yeasts are considered useful as they improve the organoleptic characteristics of the oil during preservation, whereas others are considered harmful as they can damage the quality of the oil through the hydrolysis of the triglycerides. However, some dimorphic species can also be found among the unwanted yeasts present in the oil, considered to be opportunistic pathogens to man as they have often been isolated from immunocompromised hospital patients. Present research demonstrates the presence of dimorphic yeast forms in 26% of the commercial extra virgin olive oil originating from different geographical areas, where the dimorphic yeasts are represented by 3–99.5% of the total yeasts. The classified isolates belonged to the opportunistic pathogen species Candida parapsilosis and Candida guilliermondii, while among the dimorphic yeasts considered not pathogenic to man, the Candida diddensiae species was highlighted for the first time in olive oil. The majority of the studied yeast strains resulted lipase positive, and can consequently negatively influence the oil quality through the hydrolysis of the triglycerides. Furthermore, all the strains showed a high level of affinity with some organic solvents and a differing production of biofilm in “vitro” corresponded to a greater or lesser hydrophobia of their cells. Laboratory trials indicated that the dimorphic yeasts studied are sensitive towards some components of the oil among which oleic acid, linoleic acid and triolein, whereas a less inhibiting effect was observed with tricaprilin or when the total polyphenols extracted from the oil were used. The observations carried out on a scanning electron microscope (SEM), demonstrated the production of long un-branched pseudohyphae in all the tested dimorphic yeasts when cultivated on nutrient-deficient substrates.     

Effects of olive paste fast preheating on the quality of extra virgin olive oil during storage

The olive paste obtained after crushing was fast preheated under different time/temperature conditions and then malaxed in an industrial oil mill (600 kg Frantoio/Leccino olive blend). Legal parameters (peroxides, free acidity and sensory panel), oil yield, total phenolic content, oxidative stability and phenolic profile were monitored during 12 months of storage of the virgin olive oil (VOO) kept in closed bottles in the dark. A fast preheating not longer than 72 s at 38 °C without malaxation lead to an extra VOO with a shelf-life of at least 12-months, similarly to the traditional EVOO obtained with malaxation. A fast preheating not longer than 72 s at 38 °C followed by 10 min malaxation lead to an EVOO with a ‘mild’ sensory profile and a shelf life of at least 12-months. Thus, the use of a specific designed fast preheater instead or before (a shortened) malaxation allows to obtain an EVOO with a low bitter/pungent attribute from olives which are rich of (sometimes unpleasant) phenolic compounds with the aim to meet the preference of targeted groups of consumers. Time and temperature of fast preheating are the critical parameters of the process.