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1.
The purpose of this work was to develop a procedure based on protein analysis by free zone capillary electrophoresis (FZCE) that can be used as an alternative to other methods in the determination of the technological quality of vegetable rennet to use in “Torta del Casar” cheese-making. Samples of cardoon flowers (Cynara cardunculus) grouped according to location, harvest year, and ripening stages were used in the study. For the FZCE, a protocol for extracting the methanol-soluble proteins was tested. This method was found to give good repeatability of the corrected migration time (CMT), and showed higher effectiveness in discriminating the technological properties (milk-clotting and casein degradation activities) of vegetal rennets than the SDS–PAGE technique. In addition, three peaks found in the FZCE electropherograms were examined as a good tool to predict the impact of vegetable rennet on the creaminess and overall acceptability of the “Torta del Casar” cheese.  相似文献   

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Ruyi Wu  James A. Kennedy  Yanyun Zhao 《LWT》2010,43(8):1253-1264
The effects of refrigerated storage at 2 °C and 95% RH and processing treatments on the bioactive compounds and antioxidant capacities of ‘Marion’ and ‘Evergreen’ blackberries were investigated. During refrigerated storage, total phenolics (TPC), total monomeric anthocyanins (ACY), and radical scavenging activity (RSA) fluctuated in ‘Marion’, but TPC and ACY continuously declined in ‘Evergreen’. Oxygen radical absorbance capacity (ORAC) and ferric reducing antioxidant power (FRAP) decreased by 20% and increased by 19% in ‘Evergreen’, respectively after 7-d refrigerated storage, while no changes (P > 0.05) in ‘Marion’ were observed. Compared with frozen samples, freeze-dried ‘Evergreen’ had higher TPC (21%), ACY (5.5%), and RSA (14%), while hot-air dried “Marion” had lower ACY (56%), ORAC (37%), and FRAP (27%) and hot-air dried ‘Evergreen’ had lower TPC (37%), ACY (84%), and RSA (13%). ORAC and FRAP in canned ‘Marion’ was 21-61% lower than that of frozen samples. Jam also had lower TPC and ACY (67-84%), RSA (˜80%), and ORAC and FRAP (65-77%) values than frozen ones in both varieties (P < 0.05). The 6-mo post-process room storage had little effect on the bioactive compounds of frozen and freeze dried samples, but reduced ACY in hot-air dried, canned, and jam samples, and antioxidant capacities of all samples (P < 0.05).  相似文献   

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Near infrared reflectance (NIR) spectroscopy combined with chemometrics was used to discriminate wheat varieties. A total of 249 samples of different wheat varieties from the 2003–2004 harvest were used to develop the best discriminant equation, by applying various scatters and mathematical treatments in the range of 400–2500 nm. Wheat varieties from Spain were ‘Sarina’, ‘Bolero’, ‘Berdún’, ‘Soisson’, ‘Chamorro’, ‘Artur Nick’, ‘Berdun’, ‘Marius’, ‘Anza’, ‘Kalifa’, and wheat varieties from France were ‘Galibier’ and ‘Quality’. The equation developed with the highest accuracy had an applied scatter of weighted multiplicative scatter correction, a math treatment of 2, 15, 8 (order of derivative, gap data points over which the derivative was taken, number of data points used in performing average smoothing). The percentage of correctly identified varieties was 99.5% for the calibration sample set and 94% for the validation sample set. The results demonstrated the usefulness of NIRS combined with chemometrics as a rapid method for discrimination of European wheat varieties. Although the application of the discriminant equation developed for the 2003–2004 harvest yielded a high rate, further test measurements are necessary to evaluate the robustness of the equation.  相似文献   

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Children’s food intakes are important for their health and it is their parents that mainly decide what foods are available at home. The purpose of this study was to examine the relationships between parental family food choice motives (FFCMs) and children’s intakes of ‘nutrient-dense’ and ‘energy-rich foods’. In 2008, Finnish children, aged 10-12 years, completed a 16-item food frequency questionnaire and their parents completed a 27-item questionnaire to assess the FFCMs. Matching data existed for 564 child-parent pairs. Principal component analysis was conducted. The following eight dimensions of FFCM were found: ‘health and natural content’, ‘ethical concerns’, ‘mood’, ‘convenience’, ‘price’, ‘sensory appeal’, ‘weight control’ and ‘familiarity’. The association between FFCM and children’s food intakes was analyzed by Spearman correlations and logistic regression corrected for gender, school class, gender of respondent parent, living with one parent and parental education. The results based on logistic regressions showed that the FFCMs ‘health and natural content’ and ‘sensory appeal’ were positively associated, ‘convenience’ was negatively associated with ‘nutrient-dense foods’ and ’ethical concern’ was negatively associated with ‘energy-rich foods’. Parents’ FFCMs should be considered when promoting healthy eating among children.  相似文献   

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Tocochromanols composition in apple seeds, obtained as a by-product during the fruit salad and juice production, of twelve varieties - seven crab apple (‘Kerr’, ‘Kuku’, ‘Quaker Beauty’, ‘Riku’, ‘Ritika’, ‘Ruti’ and K-8/9-24) and five dessert apples (‘Antej’, ‘Beforest’, ‘Kent’, ‘Sinap Orlovskij’ and ‘Zarja Alatau’) were studied. Tocopherols and tocotrienols were isolated using the micro-saponification method of high precision and accuracy and they were analysedanalysed by rapid RP-HPLC/FLD and RP-UPLC-ESI/MSn. Four tocopherols, with predominance of homologues α and β, were detected in each tested sample. The seeds from two apple cultivars ‘Antej’ and ‘Beforest’ were characterized by unique and similar ratios of all four tocopherol homologues α:β:γ:δ (1.7:1.5:1.3:1.0 and 2.1:2.0:1.3:1.0, respectively). The concentration range of individual tocopherol homologues (α, β, γ and δ) in apple seeds were as follows: 17.22–25.79, 7.53–29.05, 0.61–13.82 and 0.16–10.79 mg/100 g dry weight basis (dwb), respectively. Moreover, three tocotrienols (α, β and γ) were identified in lesser amounts (0.02–0.74 mg/100 g dwb). Use of apple seeds to isolate tocopherol homologues can ensure better environmental sustainability and effective use of natural plant material.  相似文献   

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Bitterness is considered as an undesirable taste of carrots. Quantitative chemical analysis of potential bitter compounds of different carrot genotypes was combined with sensory analysis in order to identify key compounds likely to be responsible for the bitterness of carrots. Eight carrot genotypes (‘Bolero’, ‘Mello Yello’, ‘Nairobi’, ‘Tornado’, ‘Purple Haze’, ‘Line 1’, ‘Line 2’, and ‘Line 3’) representing extremes in sensory-perceived odour, flavour, and taste. Potential bitter compounds like polyacetylenes, isocoumarins and phenolic acids were quantified in the peel and the corresponding peeled carrot, and their contribution to bitterness in raw carrots was analysed by sensory profiling using multivariate data analysis. Falcarindiol and a di-caffeic acid derivative were highly related to bitterness in contrast to falcarinol and other potential bitter compounds. Falcarindiol and the di-caffeic acid derivative were primarily present in the peel whereas falcarinol was almost evenly distributed in the root. Investigation of bitterness revealed that high sugar content to some extent could mask the bitter perception of carrots. As falcarinol is the most bioactive of the carrot polyacetylenes the results of the present study indicate that there is a basis for improving the health effects of raw carrots without affecting sensory quality.  相似文献   

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The purpose of this paper is to present a study of the development of the principal bioactive compounds and the physicochemical properties of the ‘Ambrunés’ Picota sweet cherry cultivar during its ripening. 5 categories of edible ripeness (termed ’ripening stages’) were determined according to the skin colour. The results show significant increases during ripening in weight, calibre, soluble solids content, fructose, total phenols, total anthocyanins and total antioxidant activity; a non-significant decrease in firmness; and significant decreases in the colour parameters of both skin and flesh and in glucose. The following compounds were identified and quantified using HPLC-DAD/ESI-MS: 5 anthocyanins, of which the most abundant was cyanidin-3-O-rutinoside; 3 hydroxycinnamic acids, principal of which was p-coumaroylquinic acid; a flavonol (rutin); and a flavan-3-ol (epicatechin), which was the least abundant of all the phenolic compounds. Because of the increased levels of bioactive compounds associated with it, ripening stage 5 was considered to represent the highest nutritional and functional quality.  相似文献   

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Quality properties of wine from Korean kiwifruit new cultivars   总被引:2,自引:0,他引:2  
Several domestic varieties of kiwifruit including Actinidia deliciosa cv. ‘Hayward’, ‘Daeheung’, ‘Monty’, ‘Arimold’, ‘Jinmi’, ‘Hyangrok’ and A. chinensis cv. ‘Haenam’ and ‘Golden King’ were utilized for the processing of wines. Kiwifruit wines were analyzed for sugar content, alcohol, acidity, pH, color, total phenols and antioxidant activity by radical scavenging assay ABTS. The soluble solid content of the kiwifruit must ranged between 22 and 25% and then was fermented at 14 °C during 4 months. The amount of alcohol productions differed especially during the first week of fermentation. Among cultivars, ‘Haenam’ and ‘Arimold’ were relatively slower than other wines with regard to alcohol production rate. The yield of wine production was increased from 63.35% to 66.19% in weight by using processing with pectinase.The ‘L’ values of wine made from ‘Hayward’ and ‘Monty’ were lower and darker than those of wines prepared from other cultivars. Wine made from ‘Daeheung’ had total phenols of 790 mg L−1, which was the highest among wines, followed by ‘Haenam’ and ‘Golden King’. ‘Daeheung’ also showed the highest antioxidant activity (22.55 mM TE L−1), while ‘Arimold’ showed the lowest one (10.91 mM TE L−1). The mean overall acceptability scores among kiwifruit wines ranged between 3.8 and 4.5. The sensory evaluations were higher in ‘Golden King’, ‘Monty’, ‘Daeheung’, ‘Arimold’, and ‘Hayward’ than those of ‘Haenam’, ‘Jinmi’, and ‘Hyangrok’. However, for commercial kiwifruit wine production not only overall sensory acceptance, but also functional properties such as total phenols and antioxidant activity, and fruit cultivation volume should be concerned. Therefore, three of kiwifruit cultivars which are ‘Golden King’, ‘Daeheung’, and ‘Hayward’ had the most desirable characteristics suitable for kiwifruit wine production.  相似文献   

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The paper reports the composition of some quality characteristics of five blackberry varieties (“C. Thornless”, “Bursa 2”, “Navaho”, “Jumbo” and “Loch Ness”). Main soluble sugar and acid contents of experimental varieties were separated, identified and quantified using high-performance liquid chromatography with photo diode array spectrophotometric and refractive index detection, for organic acids, ascorbic acids and soluble sugars, respectively. According to the results, malic acid was detected as the main organic acid while citric acid was not detected in blackberry fruits. Ascorbic acid content was found very low quantity and also was not detected in all the cultivars. As for the sugars, fructose was found as the most abundant sugar and highly detected in “Navaho”. However, the highest total sugar/malic acid ratio was found in cv. C. Thornless.  相似文献   

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Five varieties of Spanish dry cured ham were studied to assess their nutritional value in relation to fatty acids. Ten hams of the Traditional Speciality Guaranteed (TSG) “Jamón Serrano”, and the Protected Designations of Origin (PDO) “Jamón de Teruel”, “Dehesa de Extremadura”, “Jamón de Huelva” and “Guijuelo”, were analysed. Iberian hams (“Dehesa de Extremadura”, “Jamón de Huelva” and “Guijuelo”) were characterised by a lower proportion of saturated fatty acids (SFA) and a significantly higher percentage of monounsaturated fatty acids (MUFA) than white hams (“Jamón Serrano” and “Jamón de Teruel”). The Iberian varieties also showed a high proportion (approximately 50%) of C18:1 n − 9, while “Jamón Serrano” showed the highest percentage of C18:2n−6. The PUFA/SFA (P/S) ratio of the five varieties was ? 0.19, with the highest ratio corresponding to “Jamón Serrano” (0.3). The n−6/n−3 ratio was in the order of 13/1 in “Jamón Serrano” and “Jamón de Huelva”, and ranged from 9.3/1 to 10.3/1 in the other varieties. The most favourable hypocholesterolemic/Hypercholesterolemic (h/H) ratio (?2.5) was found in the Iberian varieties. TSG “Serrano” was shown to supply the lowest percentage of the recommended daily intake of MUFA, the Iberian varieties showed the highest percentage of the daily intake of long-chain PUFA, and PDO “Dehesa de Extremadura” showed the highest percentage of the intake of C18:3n−3. The higher MUFA proportion and h/H ratio observed in the Iberian hams, together with their contribution to the recommended daily intake of fatty acids, would make these products more suitable for healthier diets, although consumption must be recommended in moderation.  相似文献   

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1H nuclear magnetic resonance (NMR) was applied for the metabolic profiling of grapes from three Portuguese cultivars including ‘Trincadeira’, ‘Aragonês’, and ‘Touriga Nacional’, at four developmental stages. Two kinds of extraction methods including deuterated NMR solvent extraction and solid phase extraction (SPE) were used for the metabolomic analysis and all the metabolites detected in 1H NMR were elucidated by two-dimensional NMR techniques as well as the in-house NMR chemical shift database. Multivariate data analyses were also performed to identify overall metabolic differences. Trincadeira was found different from the other two cultivars, having low phenolic contents as compared to other cultivars. The initial stages showed comparatively high phenolics and organic acid contents like caftaric and malic acid while the later stages showed higher glucose and fructose levels. Veraison was found to be a metabolically critical stage of berry development. On the basis of these findings distribution of metabolites among different cultivars at different developmental stages is discussed.  相似文献   

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The flavonoid composition of flavedos and juices from four Chinese pummelo cultivars (Citrus grandis ‘Shatianyu’, C. grandis ‘Guanximiyu’, C. grandis ‘Yuhuanyu’, and C. grandis ‘Cuixiangtianyu’) and one grapefruit cultivar (Citrus paradisi ‘Changshanhuyu’), was investigated using high-performance liquid chromatography diode array detection electrospray ionisation mass spectrometry (HPLC-DAD-ESI MS/MS). Twenty-eight flavonoids were identified. Naringin was the predominant flavanone in these pummelo varieties, whereas naringin and neohesperidin were the principal flavanones found in C. paradisi ‘Changshanhuyu’. The four pummelo cultivars had higher levels of flavones when compared with the grapefruit. Based on the flavonoid profiles in flavedos and juices, four pummelo cultivars and one grapefruit cultivar were well separated.  相似文献   

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The primary objective of this work was to evaluate whether sweet cherries could make an acceptable fresh-cut fruit product. The concept was to develop a cherry product cut such that the pit and associated tissue from stem bowl to the nose of the fruit were removed in a single cutting operation, leaving a cherry with a ‘hole’ which could be filled with various foodstuffs (much like a pitted olive). Secondary objectives were to determine if the design of the cutting tube, storage at low temperature before cutting or preharvest treatment with gibberellic acid (GA: used to improve firmness in commercial production) could influence the quality of packaged fresh-cut sweet cherries. Most cultivars of sweet cherries tested appeared to be suitable for cutting, and quality was not impacted significantly if GA was used on the fruit prior to harvest. Low temperature of the fruit at the time of cutting appeared to lead to greater deterioration than warm temperatures and so perhaps a warm-up time is required if the fruit are held in cold storage before cutting. Finally, the design of the cutting tube was of great importance with a scalloped-edge resulting in a lower cutting force, and hence less injury and better quality, than a straight-edge design.  相似文献   

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