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1.
Apostolos Kiritsakis Pericles Markakis 《Journal of the science of food and agriculture》1984,35(6):677-678
The titratable acidity and the peroxide value of olive oil extracted from olives harvested by shaking the trees over subtented nets increase rapidly as the residence of the fruit on the nets is prolonged. It is recommended that the extraction of the oil from the fruits is not delayed for longer than 2 to 3 weeks. 相似文献
2.
An experimental investigation was carried out to evaluate the influence the different temperatures at which olives are hammer-crushed and paste kneaded had on the quality of oil and particularly on the phenolic components. The results obtained showed that temperature influenced the diffusion of phenolic compounds in oil. Greater amounts of hydroxytyrosol, tyrosol, caffeic acid, hydroxycaffeic acid and oleuropeine were measured in oils obtained from previously refrigerated olives. Kneading brought about a reduction of total phenols when it was performed on olives crushed at a higher temperature (18vv°C) while it led to a slight increase when it was executed on pastes of previously refrigerated olives (6vv°C). 相似文献
3.
张劲松 《中外食品工业信息》2012,(4):42-42
生产企业:深圳市巨万阳光食品股份有限公司关键字:高端品类时尚消费群体扩大2010年之前的数年里,进入中国市场的橄榄油品类,在市场培育方面一直表现的不温不火,那是有许多因素制约的,比如在那些年里,花生油占主导,是因为消费者的口感需求要高于健康需求,再有一点是橄榄油属高端品类,消费者经济水平有待提高。 相似文献
4.
Raquel B. Gómez-Coca María del Carmen Pérez-Camino Wenceslao Moreda 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2016,33(3):391-402
Olive fruits contain an n-alkane series of saturated hydrocarbons mainly in the pulp. Lower amounts of a complex mixture of paraffins, unresolved by gas chromatography (UCM – unresolved complex mixture), have been found in cuticle, stone (woody shell and seed), olive leaves, and talc used as an aid to olive oil extraction. The amounts of both kinds of hydrocarbons are related to the olive cultivar and are transferred to oils in a proportion depending on the oil-obtaining process (centrifugation or solvent extraction). In olive oil obtained by centrifugation, only n-alkanes were detected. However, in olive oil extracted by second centrifugation, small amounts of UCM paraffins were detected together with the n-alkanes. Olive pomace oils showed a very variable content of both types of hydrocarbons according to the different obtaining process, such as double centrifugation, solvent extraction or centrifugation followed by solvent extraction. ‘White mineral oil’ used in oil extraction machinery is the source of the high concentrations of UCM paraffins found in some olive and olive pomace oils. In the case of second centrifugation olive oil, a maximum limit of 50 mg kg?1 of UCM is suggested, whereas in the case of crude olive pomace oil, it amounts to 250 mg kg?1 plus an additional minimum of 1.0 for the n-alkanes/UCM ratio. 相似文献
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橄榄油的化学组成及对人体的营养价值 总被引:24,自引:1,他引:23
0前言油橄榄(OleaeuropaeaL)又称洋橄榄 ,是世界名贵常绿木本油料和果用树科 ;在植物学上属于木犀科 ,木犀科属 ;原产于小亚细亚 ,主要分布在地中海沿岸地区 ,以西班牙、意大利、葡萄牙及阿尔巴尼亚为集中产地 ,现在世界各国引种栽培 ,总面积已达600多万hm2。1978年甘肃省陇南地区开始引种 ,其表现适应性强、生长快、结果早、产量高、油质好、没有病虫害等特点 ,其油质量符合国家标准 ,为我国油橄榄最佳适应区。从油橄榄果实中榨取的油称为橄榄油 ,鲜果含油率一般为20 %~30 % ,其油年总产量约为200万t,… 相似文献
6.
Giuliani A Cerretani L Cichelli A 《Critical reviews in food science and nutrition》2011,51(7):678-690
The chlorophylls are responsible for the characteristic green color of the olive fruits and their products. Virgin olive oil (VOO) is obtained from processing olives only by mechanical and physical means under conditions ensuring that the natural characteristics of the fruit composition are maintained as far as possible. In terms of the total chlorophyll content of oil, the extraction process entails a loss of chlorophyll of up to 80%. Many factors, both agronomical and technological, can affect the presence of green pigments in VOO. The analysis of green pigments in olives and/or oil requires an initial phase of extraction of these compounds from the solid and fluid matrix, followed by the selective separation and subsequent identification of the different components of the chlorophyll fraction. The aim of this review article is to summarize and critically analyze the available information about chlorophylls in VOO. 相似文献
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This paper presents the investigation of the chlorophyll and carotenoid pigments composition in monovarietal virgin olive oils produced from the five main olive varieties (Minuta, Ottobratica, Calabrese, Ogliarola, Baddarica) cultivated in Sicily (southern Italy), from four main olive varieties (DolceAgogia, Moraiolo, Leccino, Frantoio) cultivated in Umbria (central Italy), and from three main olive varieties (Leccino, Oliva Nera di Collecorto, Noccioluta) cultivated in Molise (central Italy). Reversed-phase high performance liquid chromatography using a C-30 column with photodiode array detection was used for pigments analyses. In all, 19 compounds were identified and quantified in 60 olive oils samples. The qualitative pigments pattern was similar among the varieties investigated, whereas quantitative differences were found among the different cultivars; among the varieties investigated in this work, the oils from Umbria showed the highest pigment content (34.19 ppm in average), followed by the oils from Molise (18.61 ppm in average) and the oils from Sicily which showed the lowest pigment contents (13.38 ppm in average). In general, pheophytin a was the major component (range 0.49–19.42 ppm), followed by β-carotene (range 1.27–9.30 ppm) and lutein (range 0.44–5.12 ppm). Those differences may be due to genetic factors and/or geographical differences. Moreover, auroxanthin was detected for the first time in olive oils and was detected only in olive oils from Umbria and Molise regions. The ratio between the two isochromic pigment fractions, namely the ratio between the chlorophyll and carotenoid fractions showed an average value close to unity. The lutein/β-carotene ratio was less than one in the majority of the cases. These parameters, along with other analytical parameters, could be used as indicators of typicality in olive oils. The presence of a specific pigment profile in olive oils could infact be used to guarantee the genuineness of the product, since the quality control of food requires a precise knowledge of the pigments composition of the original products. 相似文献
8.
Daniele Giuffrida Francesco SalvoAndrea Salvo Lara La PeraGiacomo Dugo 《Food chemistry》2007,101(2):833-837
This paper presents the first investigation of the chlorophyll and carotenoid pigments composition in sicilian monovarietal virgin olive oils from the three (Cerasuola, Nocellara, Biancolilla) main olive varieties cultivated in Sicily (Italy). In all, 19 compounds were identified and quantified in 24 olive oil samples. The application of reversed-phase liquid chromatography with photodiode array detection using a C-30 column in the simultaneous qualitative–quantitative analysis of virgin olive oils pigments, has been shown. The qualitative pigment pattern was similar among the varieties investigated, whereas quantitative differences were found among the different cultivars, which can all be considered as having an high pigment content. Pheophytin a, was the major component (19.36–25.04 ppm), followed by β-carotene (8.06–16.27 ppm). Pheophytin a′ (2.92–4.17 ppm), lutein (2.28–4.49 ppm) and neoxanthin (1.54–2.11 ppm) were also well represented. The presence of carotenoid esters was also detected. The neoxanthin and β-carotene contents were higher compared to reports present in the literature for other olive oil varieties. This may be due to genetic factors and/or geographical differences. The ratio between the two isochromic pigment fractions, namely the chlorophyll and the carotenoid fractions, was around one in all varieties, showing that they were in balance. The lutein/β-carotene ratio was less than one in all cases. These parameters, along with other analytical parameters, could be used as indicators of typicality in olive oils. The presence of a specific pigment profile in olive oils could in fact be used to guarantee the genuineness of the product, since the quality control of food requires a precise knowledge of the pigments composition of the original products. 相似文献
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El Riachy M Priego-Capote F León L Luque de Castro MD Rallo L 《Journal of the science of food and agriculture》2012,92(12):2524-2533
BACKGROUND: The progressive transformation of olive growing and the increasing demands for high‐quality monovarietal virgin olive oil (VOO) have triggered interest in olive breeding programs, in which the evaluation of the new genotypes is the basis for obtaining new olive cultivars. In this work, the phenolic composition of VOOs from two progenies from crosses between ‘Arbequina’, ‘Arbosana’ and ‘Sikitita’ has been evaluated along two years. RESULTS: A higher degree of variation was observed in segregating population as compared to genitors. The results also showed that the variability within crosses constitutes the major contribution to total variance for all considered parameters (>92% of total sum of squares). All compounds under study were present in oils obtained in both years; however, clear differences in their concentrations were observed between years. CONCLUSION: Olive breeding can indeed provide genotypes that produce oils with improved phenolic profiles as compared to traditional cultivars. In addition, the data showed that selection as a function of tyrosol content could be achieved in only one crop year. Finally, p‐coumaric acid was the unique component able to discriminate between both crop years under study. Copyright © 2012 Society of Chemical Industry 相似文献
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Antonio M. Inarejos-García G. Fregapane M. Desamparados Salvador 《European Food Research and Technology》2011,232(3):441-451
The present study focuses on the influence of the olive crushing technique on the minor composition of olive pastes and their
corresponding virgin olive oils since these compounds are strongly related to their quality and characteristics. Two different
cultivars, Arbequina and Cornicabra—known for their different minor component composition—were processed at laboratory scale
using hammer mills at various breakage forces and grid hole diameters, a blade cutter and a mortar. Crushing and kneading
produce a profound change in the composition of the phenolic compounds in the olive paste and in the final oil. Hydroxytyrosol
derivatives in virgin olive oil were most affected by the crushing conditions. The stronger the crushing conditions (i.e.
hammer crushers using smaller grid holes and a higher rotation speed), the higher the phenolic content in both olive paste
and oil in both varieties. Interestingly, the effect on volatile compounds of milder or stronger crushing conditions was opposite
to that described for the phenolic compounds. 相似文献
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Syrian Kaissy cv olive fruit (SKOF) was irradiated (0, 1, 2, and 3 kGy). Oils were extracted from irradiated and un-irradiated olive fruits. Fatty acid profiles of Syrian Kaissy cv olive oil (SKOO) were measured by gas chromatography immediately after irradiation and after 6, 12, 24, and 36 months of storage. Results of the study showed that composition of fatty acids of SKOO were determined as palmitic (C16:0) (14.69%), palmitoleic acid (C16:1) (1.18%), stearic (C18:0) (2.19), oleic (C18:1) (68.94%), linoleic (C18:2) (12.22%), and linolenic acid (C18:3) (0.79%). The fatty acid composition of SKOO contains a healthy mixture of all the types of saturated mono-unsaturated and poly-unsaturated fatty acids. The data showed an increase (p < 0.05) in the percentage of the total saturated fatty acids and decrease (p < 0.05) in the percentage of the total unsaturated fatty acids of SKOO during storage. In general, there were no significant (p > 0.05) differences in fatty acids compositions of both oils extracted from irradiated and un-irradiated SKOF. 相似文献
15.
Susana M Cardoso Sylvain Guyot Nathalie Marnet Jos A Lopes‐da‐Silva Catherine MGC Renard Manuel A Coimbra 《Journal of the science of food and agriculture》2005,85(1):21-32
Methanol extracts of olive pomace (two‐phase olive oil extraction) and olive pulp were analysed by reverse phase HPLC and the eluted fractions were characterised by electrospray ionisation mass spectrometry. This technique allowed the identification of some common phenolic compounds, namely, verbascoside, rutin, caffeoyl‐quinic acid, luteolin‐4‐glucoside and 11‐methyl‐oleoside. Hydroxytyrosol‐1′‐β‐glucoside, luteolin‐7‐rutinoside and oleoside were also detected. Moreover, this technique enabled the identification, for the first time in Olea europaea tissues, of two oleoside derivatives, 6′‐β‐glucopyranosyl‐oleoside and 6′‐β‐rhamnopyranosyl‐oleoside, and of 10‐hydroxy‐oleuropein. Also, an oleuropein glucoside that had previously been identified in olive leaves was now detected in olive fruit, both in olive pulp and olive pomace. With the exception of oleoside and oleuropein, the majority of phenolic compounds were found to occur in equivalent amounts in olive pulp and olive pomace. Oleoside was the main phenolic compound in olive pulp (31.6 mg g?1) but was reduced to 3.6 mg g?1 in olive pomace, and oleuropein (2.7 mg g?1 in the pulp) almost disappeared (<0.1 mg g?1 in the pomace). Both these phenolic compounds were degraded during the olive oil extraction process. Copyright © 2004 Society of Chemical Industry 相似文献
16.
Jelena Milosevic David S. Ashton & Michael J. Cocksedge 《International Journal of Food Science & Technology》2002,37(5):523-526
Olive oil is a major constituent of many food preparations and is used in margarine and as a cooking oil. Olive oil consists of lipidic components, mainly fatty acids, in differing proportions depending on the source of the olive and the method of preparation. Although several studies have been made on the lipid composition of the extracted oil, no detailed analysis has been made on olive skin as a discrete entity. Analysis by gas chromatography (GC) of an olive skin extract showed oleic acid (61.45%), palmitic acid (15.28%) and linoleic acid (11.69%) to predominate. Smaller amounts of other fatty acids, not previously detected in olive fruit, were also found to be present in olive skin. 相似文献
17.
Yosra Allouche Antonio Jiménez Marino Uceda M. Paz Aguilera José Juan Gaforio Gabriel Beltrán 《Food chemistry》2010
The influence of olive paste preparation conditions on the triterpenic content of virgin olive oils from Arbequina and Picual cultivars was investigated. For this purpose, three sieve diameters of the hammer mill (4, 5, and 6 mm), two malaxation temperatures (20 and 30 °C), and two malaxation times (20 and 40 min) were tested. Results obtained showed that for Arbequina oils, a finer crushing level resulted in higher maslinic acid and erythrodiol content. Increasing malaxing temperature and time lead to a rise in both oleanolic and maslinic acid concentration, whereas erythrodiol content increased only for the longer malaxation time. For Picual oils, higher concentrations of oleanolic acid, maslinic acid, and uvaol were obtained by prolonging the paste malaxation time. A finer crushing level resulted also in an increase of maslinic acid content. These findings suggest that virgin olive oil triterpenic composition can be improved by regulating olive paste preparation conditions. 相似文献
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Effects of ultrasound-accelerated debittering (UAD) at different NaOH concentrations (1.50, 1.75, and 2.00% w/v) and temperatures (25, 30 and 35 °C) on physicochemical and textural properties of olive fruits were investigated and compared with conventional debittering (CD). In UAD, processing time decreased up to 48% in comparison with CD method. During debittering, increasing moisture and decreasing nitrogen and ash contents of the samples were observed. In UAD, reduction rate of phenolic compounds and as a result the speed of debittering process increased in comparison with CD method. UAD was able to reduce textural hardness at a higher rate than CD method. Fatty acid compositions of UAD and CD samples were similar. Both UAD and CD methods similarly caused considerable damages to the structure of olives as observed on micrographs. Overall, UAD method was able to debitter olive fruits at a higher rate without causing any undesirable changes. This can have practical implications in reducing NaOH and water usage for olive processing.Industrial relevanceIn this research, the efficacy of ultrasound-assisted debittering (UAD) of olive fruit was evaluated. UAD increased the rate of sodium hydroxide penetration into the olive flesh, leading to a higher rate of oleuropein hydrolysis and significant reduction of processing time of up to 48% in comparison with CD method. Therefore, ultrasound-assisted debittering was found to be a suitable and applicable technique in minimizing debittering time of olive fruits and reducing NaOH concentration. It is also possible to reduce the number of wash-cycles required for the completion of debittering resulting in substantial reduction in water usage. 相似文献