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81.
Gustavo González‐Neves Graciela Gil Guzmán Favre Milka Ferrer 《International Journal of Food Science & Technology》2012,47(5):900-909
The anthocyanin composition of Tannat red wines obtained with four winemaking techniques was evaluated in different years. The wines were elaborated with traditional maceration (TM), cold pre‐fermentative maceration, delayed extraction of anthocyanins and extended maceration. Two vinifications were carried out for each technique, employing 70 kg of grapes in each one. The anthocyanin composition of wines was analysed by high‐performance liquid chromatography–diode array detection. The results confirm the fundamental role of the grape composition on the anthocyanin composition of the wines. The winemaking had an important effect on the total concentration of anthocyanins and also may modify the anthocyanic profile of wines. The wines obtained with TM had higher or similar content of anthocyanins than those elaborated with the other techniques. Canonical discriminant analysis of data showed that vintage has a greater effect on anthocyanin concentration than winemaking techniques. 相似文献
82.
Y. L. Machado A. A. Dantas Neto J. L. C. Fonseca T. N. C. Dantas 《Journal of the American Oil Chemists' Society》2014,91(7):1139-1145
The PetroOXY method was used to evaluate the kinetics of oxidation of two edible vegetable oils, extracted from moringa and passion fruit. This method, which uses pure oxygen at 700 kPa is effective and fast and our experiments were carried out at temperatures 110–140 °C with BHA antioxidant additive concentration ranging from 0 to 500 ppm. Moringa and passion fruit oils followed first-order kinetics although, in the case of passion fruit oil, mathematical approximations in the first-order kinetic expression resulted in a final equation that could also be interpreted as deriving from zero-order kinetics. The higher stability of moringa oil was characterized by an activation enthalpy ca. 50 % higher than the one related to passion fruit oil. 相似文献
83.
《Food Control》2014
As a traditional alcoholic beverage, Chinese rice wine is quite popular for its unique flavor and high nutritional value. In this study, we investigated the changes of flavor compounds in varying stages of fermentation by HS-SPME-GC-MS and HPLC. In addition, 16s rDNA-PCR was utilized to analyze the changes of bacterial communities during fermentation of Chinese rice wine from the Shaoxing region. It was noted that the content of flavor compounds including esters, higher alcohols, amino acids and organic acids was different in varying stages of fermentation. In general, the flavor compounds of Chinese rice wine were mainly produced after pre-fermentation. The results also showed that the bacterial community structures and diversity of Chinese rice wine varied significantly during different fermentation stages, and more than 10 genera of bacteria was detected in Chinese rice wine fermentation broth. Among these specific bacteria identified in the study, Lactobacillus (the predominant genus) and Bacillus might take an active part in flavor development in Chinese rice wine. This implied that these bacteria might play significant contributions on the flavor of Chinese rice wine. 相似文献
84.
Fast headspace-enantioselective GC-mass spectrometric-multivariate statistical method for routine authentication of flavoured fruit foods 总被引:1,自引:0,他引:1
Cecilia CaglieroCarlo Bicchi Chiara CorderoPatrizia Rubiolo Barbara SgorbiniErica Liberto 《Food chemistry》2012,132(2):1071-1079
This study describes a rapid total analysis system (TAS) to detect the authenticity of fruit-flavoured foods and beverages by on-line combining headspace solid phase microextraction (HS-SPME) with enantioselective GC-MS (Es-GC-MS) and statistical multivariate methods (PCA, HCA). Peach, coconut, apricot, raspberry, as fruits mainly characterised by γ- and δ-lactones as chiral markers, strawberry (α-ionone, linalool, nerolidol, ethyl 2-methylbutyrate, 2-methylbutyric acid and γ-lactones) and melon (ethyl 2-methylbutyrate and 2-methylbutanol) were investigated. The system was developed by (a) optimising non-equilibrium HS-SPME sample preparation, (b) speeding-up ES-GC using cyclodextrin derivatives as chiral selectors with conventional and narrow-bore columns and (c) elaborating data by multivariate methods. The resulting TAS affords a reduction of the time needed for the whole analytical process from about 150 min to 20-50 min (67-87% of the current routine method) depending on matrix, sampling and analysis conditions and Es-GC columns. 相似文献
85.
《Journal of the Institute of Brewing》2017,123(2):268-276
An infusion of tea leaves was prepared using 4 g tea/100 mL of the apple juice, ameliorated with different sugar sources, supplemented with different nitrogen sources and inoculated with 5% incola (Saccharomyces cerevisiae var. ellipsoideus , consortia 1 and consortia 2). The highest rate of fermentation and ethanol were found in the apple tea wine having sucrose as a sugar source, while apple juice concentrate as a sugar source gave the highest total phenols, caffeine content and overall acceptability. Higher alcohols, volatile acidity and antioxidant activity were the highest in honey as a sugar source. Apple tea wine having DAHP as a nitrogen source documented the highest ethanol, caffeine content and overall acceptability, lowest higher alcohols, whereas peptone as a nitrogen source had the highest total phenols. Among the different types of inocula, for most of the parameters there were non‐significant differences. However, must inoculated with S. cerevisiae var. ellipsoideus for the preparation of apple tea wine resulted in the highest fermentation efficiency, ethanol and overall acceptability but the lowest volatile acidity. Apple tea wine prepared by ameliorating the apple tea must with apple juice concentrate, DAHP and inoculated with S. cerevisiae var. ellipsoideus was rated as the best. Copyright © 2017 The Institute of Brewing & Distilling 相似文献
86.
Jonathan Sampath Franklyne Swati Iyer Andrew Ebenazer Amitava Mukherjee Natarajan Chandrasekaran 《International Journal of Food Science & Technology》2019,54(9):2802-2810
Many human acid tolerant bacterial and fungal pathogens can be transmitted through the consumption of the contaminated fruit juices. We aim to formulate essential oil nanoemulsions (basil, black seed, turmeric, clove & cinnamon), determine their ability to clear contamination by food borne bacterial pathogens from fruit juices. The antibacterial activity of the optimised formulations was tested in the fruit juices against bacterial pathogens causing gastrointestinal tract infections. The minimum bactericidal concentration (MBC) of clove emulsions ranged from 15.6 to 25 μL mL−1. Cinnamon oil emulsion had an MBC ranging between 15 and 31 μL mL−1. At MBC, cinnamon oil emulsions caused a 6log10 decrease in viable counts by 8 h and maintained the sterility of fruit juices for 7 days at ambient temperature. Thus, clove and cinnamon microemulsions can be used as juice additives to control food borne bacterial pathogens and maintain the bacterial sterility of fruit juices. 相似文献
87.
88.
Giuseppe Grosso Stefano Marventano Justin Yang Agnieszka Micek Andrzej Pajak Luca Scalfi 《Critical reviews in food science and nutrition》2017,57(15):3218-3232
Many studies have reported that higher adherence to Mediterranean diet may decrease cardiovascular disease (CVD) incidence and mortality. We performed a meta-analysis to explore the association in prospective studies and randomized control trials (RCTs) between Mediterranean diet adherence and CVD incidence and mortality. The PubMed database was searched up to June 2014. A total of 17 studies were extracted and 11 qualified for the quantitative analysis. Individuals in the highest quantile of adherence to the diet had lower incidence [relative risk (RR): 0.76, 95% confidence intervals (CI): 0.68, 0.83] and mortality (RR: 0.76, 95% CI: 0.68, 0.83) from CVD compared to those least adherent. A significant reduction of risk was found also for coronary heart disease (CHD) (RR: 0.72, 95% CI: 0.60, 0.86), myocardial infarction (MI) (RR: 0.67; 95% CI: 0.54, 0.83), and stroke (RR: 0.76; 95% CI: 0.60, 0.96) incidence. Pooled analyses of individual components of the diet revealed that the protective effects of the diet appear to be most attributable to olive oil, fruits, vegetables, and legumes. An average reduced risk of 40% for the aforementioned outcomes has been retrieved when pooling results of RCTs. A Mediterranean dietary pattern is associated with lower risks of CVD incidence and mortality, including CHD and MI. The relative effects of specific food groups should be further investigated. 相似文献
89.
以龙眼、贵人香、雷司令和玫瑰香甜白葡萄酒为参照对象,采用气相色谱、液相色谱及感官品评等技术分析小芒森甜白葡萄酒质量指标的特点。结果表明,小芒森葡萄酒中的2-甲基-1-丁醇、3-甲基-1-丁醇、乙酸乙酯、丁二酸二乙酯、咖啡酰酒石酸含量高于其他类型的甜白葡萄酒;咖啡酸、酒石酸、苹果酸、对位香豆酸和对羟基苯甲酸在小芒森甜白葡萄酒中的含量也相对偏高,上述成分是影响小芒森甜白葡萄酒风味的关键性指标。感官品评结果表明,在色泽和香气方面,小芒森甜白葡萄酒明显优于其他几种类型的甜白葡萄酒,很可能与其含量较高的酸类、醇类和酯类等成分有关。 相似文献
90.
Natalia Brossard Beatriz Gonzalez-Muñoz Carolina Pavez Arianna Ricci Xinmiao Wang Fernando Osorio Edmundo Bordeu Giuseppina Paola Parpinello Jianshe Chen 《International Journal of Food Science & Technology》2021,56(10):5382-5394
Astringency is a sensory attribute, related to the quality and mouthfeel of red wines. However, the origin of astringency sub-qualities, such as the typical drying astringency found in immature grapes, is still unknown. Astringency of red wines with similar tannin content but different astringency sub-qualities, from different harvest dates, is studied. Astringency was characterised in terms of friction coefficient, polyphenol content, sensory analysis and tannin/salivary–proteins aggregates characterisation. A different evolution during ripening was found for both Cabernet Sauvignon and Carménère, and tannin–protein aggregates showed differences in size, shape and surface. The velvety sub-quality appears to be related to aggregates with low precipitation, and with specific surface characteristics as roundness and Feret diameter. Results from this work propose an effect of aggregates on sensory perception and opens the possibility to explore their effect on oral lubrication. 相似文献