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1.
《LWT》2003,36(6):585-590
The Vitis vinifera Albariño is a considerably acid white Galician variety, with an important aromatic potential. The composition of the grape at the harvest date during four consecutive years is reflected in this paper. The normal parameters of total acidity, pH, and sugar and malic acid contents, were determined according to the official methods of the OIV. Aromatic compounds extracted from the grape sample using C18 cartridges were identified and quantified by gas chromatography/mass spectrometry. The results obtained demonstrate a high content of bound form aromatic compounds and that, of the responsible compounds for the varietal aroma, linalool, geraniol, benzyl alcohol and 2-phenylethanol predominate. This supports the observation of the floral character of the variety.  相似文献   

2.
The Kōfu Basin in Yamanashi Prefecture is at the center of table grape and wine production in Japan. This article traces the historical geographies of the growing and fermentation of Delaware grapes in this region. Data were gathered from over 145 interviews with stakeholders across the table grape and wine industries, extensive archival research and participant observation as a grape farmer in the Kōfu Basin for over one and a half years. Emphasis is placed on intertwining that history to overarching developments in local viticulture and winemaking. This includes tracing the arrival of the cultivar from the USA to Japan at the start of the Meiji Restoration in 1868, early fermentation and later rapid diffusion linked to its popularity as the first commercially available seedless cultivar. Delaware reached the pinnacle of its popularity as a grape for the table and wine in the 1960s and 1970s, before changes in consumer demands to higher value table grapes and away from sweet wines led to its fairly rapid decline. Although significantly less Delaware is grown or fermented today, this introduced grape was and surprisingly continues to be highly influential on the developmental trajectories of Japanese grape growing and winemaking.  相似文献   

3.
Berry size and crop yield are widely recognized as important factors that contribute to wine quality. The final berry size indirectly affects the phenolic concentration of the wine due to skin surface-to-berry volume ratio. The effects of different irrigation levels, soil management and plant crop level on growth of ‘Trincadeira’ berries were studied. In order to test the influence of different irrigation levels (rainfed, pre-veraison and post-veraison), different soil management (tillage and natural cover crops) and different plant crop levels (8 and 16 clusters per vine), leaf water potential, skin anthocyanin, polyphenols, berry skin and seed fresh weight were measured in fruits. The segregation of berries into three different berry classes: small, medium and large, allowed to identify different levels of contribution of soil management and irrigation level into berry, skin and seeds ratios. As expected, higher water availability due to irrigation and soil tillage management during berry development induced an increase in berry flesh weight and this was more evident in larger berries; however, berry skin and seed fresh weight remained unchanged. Also, anthocyanins did not show significant differences.  相似文献   

4.
This research was undertaken to determine biochemical properties of β-glucosidase (β-d-glucoside glucohydrolase, EC 3.2.1.21) isolated from Muscat of Bornova grape. The optimum pH for β-glucosidase activity was found to be 5.0, and the enzyme showed high activity over a broad pH range of 4.5–6.0. However, due to low activity at pH 3.0, the enzyme is expected to exhibit only a fraction of the maximum activity during grape juice fermentation due to low pH of grape juice. As the temperature increased from 30 to 55 °C, the activity increased, too, the maximum activity occurring at 55 °C which implies that the enzyme is expected to exhibit a low activity at grape juice fermentation. According to thermal inactivation studies, k D values increased as the temperature increased, whereas half-life and D values decreased. Energy of activation (E a) and Z values were found to be 120.99 kj mol?1 (r 2 = 0.9776) and 18.08 °C (r 2 = 0.9750), respectively. d-glucose and ethyl alcohol inhibited the enzyme at varying degrees depending on the concentration.  相似文献   

5.
Phenolic compounds, related to antioxidative and antifungal properties of ethanolic extracts from five commercial grape cultivars (three red and two white) grown in Turkey were determined. A reversed-phase high performance liquid chromatography (RP-HPLC) procedure was developed, and a total 18 different phenolic compounds were identified. Total phenolic contents of the extracts were determined using Folin–Ciocalteau method. Antioxidant activities of the extracts were evaluated by using DPPH radical scavenging and phosphomolybdenum methods. All extracts exhibited strong antioxidant and antiradical activity. Phenolic compounds and antioxidant activities of the extracts were variety dependent. Antifungal activities of the pomaces and extracts were screened by both in vitro agar-well diffusion assay and antifungal activity in apple and orange juices in situ using Zygosaccharomyces rouxii and Z. bailii. Antifungal activities revealed that the pomaces and extracts of Gamay and Kalecik karasi could be more effective antifungal agents than those of Emir, Narince and Okuzgozu grape cultivars.  相似文献   

6.
7.
A multi-residue method for the analysis of 175 pesticides was developed by online gel permeation chromatography–gas chromatography/mass spectrometry (GPC–GC/MS) to study pesticide distribution and migration between peel and pulp in grape. The separated peel and pulp samples were extracted by acetonitrile after fortified with chlorpyrifos-d10 isotope internal standard. The extract was first purified by solid phase distribution sorbent of primary secondary amine (PSA) and then detected by online GPC–GC/MS. At the spiking levels of 10, 50 and 200 μg kg−1, 73.7%, 94.3% and 98.9% of the pesticides, respectively, presented recoveries between 70% and 120%. The ratios were 91.4%, 94.9% and 92.0%, respectively, for the relative standard deviations (RSDs) bellow 15%. Limits of detection (LODs) for the pesticides in pulp were below 10 μg kg−1. Pesticides were separated to four groups according to the distribution ratios (peel/whole grape) of 100%, 80–99.9%, 50–80% and 0–50% in peel. Relationship between the pesticide distribution and corresponding regulation of EU maximum residue level (MRL) was discussed. Six factors influencing the pesticides distribution and migration between peel and pulp were discussed. Weak linear correlation between the pesticide solubility in water (20 °C) and the distribution ratios (lowest and average) in peel was found for most of the detected pesticides with solubility less than 200 mg L−1.  相似文献   

8.
9.
The efficiency of grape stem extracts to express antiradical activity was assessed using two different approaches and DPPH as the radical probe. In addition, the mixture effects when the extracts were combined with ascorbic acid (AA) and α-tocopherol (α-Tcp) were also evaluated. The approaches included a simple linear regression analysis between the response (antiradical activity) and concentration, but also a response surface methodology, which permitted the monitoring of the response upon simultaneous variation of both the concentration of the total polyphenols of the extracts and either of the antioxidants (AA and α-Tcp). The deployment of linear regression poses important constraints with regard to concentration ranges, whereas response surface methodology might be a valuable statistical tool for similar assessments and credible modelling of binary mixtures of antioxidants. In all combinations tested it was found that an antagonism was manifested, presumably as a result of AA and α-Tcp regeneration by the extract polyphenols, at the expense of the latter.  相似文献   

10.
Volatile aroma compounds are one of the important characteristics determining fruit quality. Evaluation of volatiles at the germplasm level is useful for future breeding efforts, aimed at improvement of fruit quality, via effects on fruit aroma. The composition and concentration of volatiles in berries of forty-two grape cultivars belonging to seven genotypic groups were evaluated by headspace solid-phase microextraction with GC–MS. Sixty volatiles were detected, of which C6 compounds were the dominant volatiles in V. amurensis grape, neutral cultivars V. vinifera grapes and hybrid grapes between V. vinifera with V. thunbergii or V. amurensis. Alcohols and carbonyls were relatively low in all Vitis germplasm studied. Terpenoids were abundant in V. vinifera with muscat aroma, while esters were dominant in V. labrusca and its hybrids with V. vinifera or V. amurensis. Via principal component analysis, all the grape germplasm studied could be divided into three groups: (1) V. labrusca and its hybrids with V. vinifera or V. amurensis, (2) V. vinifera with muscat aroma and (3) the others, including V. vinifera without muscat aroma plus V. amurensis, and hybrids between V. vinifera and V. thunbergii or V. amurensis. Seasonal quantitative variations of volatiles were observed, but the qualitative volatile composition of the cultivars was consistent.  相似文献   

11.
Berry shrinkage in ripening grapes cv. Shiraz is systemic within a given grapevine and coincident between grapevines in any given season. In this present study on weight loss in ripening berries, ripening curves of non-solutes per berry (largely water) were similar to curves for berry weight (as a function of time). Both sets of curves were equivalent with respect to timing of maximum weights and subsequent rates of weight loss. However, curves of solutes per berry (largely sugar) increased steeply up to the time of maximum berry weight, then slowed and plateau-ed. We suggest that phloem sap is the sole source for water and solutes that enter grape berries subsequent to veraison, and accumulate until maximum berry weight. We further suggest that phloem flow becomes impeded at maximum berry weight.
As berry ripening proceeds, continuation of berry transpiration leads to berry shrinkage and a concentration of solutes; i.e. any increase in juice Brix depends on shrinkage. One implication is that assimilates enter a berry up to the onset of shrinkage, whereafter accumulation of non-anthocyanin glycosides (including glycosides of flavour compounds) depends upon their synthesis in situ.  相似文献   

12.
The influence of noble rot on the quality of Recioto di Soave, a “passito” sweet white wine, is greatly variable depending on the occurrence of favourable seasonal conditions for the mould infection. Botrytized wines were produced from grapes inoculated with conidia suspensions to evaluate the effects of noble rot on volatile compounds profile of Recioto di Soave wine. Different development stages of Botrytis cinerea and degree of grape withering were ascertained by must analysis. Several volatile components were involved in marked changes depending on the infection and grape withering level. Fruity esters, carbonyl compounds, phenols, lactones and acetamides greatly changed among botrytized wines. The results demonstrated that the level of B. cinerea infection and the degree of grape withering exert considerable influence on the volatile composition of this sweet wine. Strain-dependent effects were also preliminary ascertained. The process of induction of grape botrytization presented in this study could be recommendable for the industrial production of botrytized Recioto di Soave wine.  相似文献   

13.
A fast and sensitive multi-residue analysis method is reported for simultaneous determination of 25 pesticides of chemical classes which are spiked into fresh grape. The sample pretreatment method involves extraction and clean-up in one step with SiO2 hollow fibre from 1.0 mL fresh grape slurry to minimise the matrix effects, and determination by gas chromatography–mass spectrometry with selective ion monitoring mode. The validation of the optimised method in terms of linearity, precision, recovery and repeatability showed that the proposed procedure is sensitive (the limits of detection were in the range of 0.0009–0.0084 μg mL−1 for 25 pesticides), precise and repeatable (average recoveries were between 61% and 108% with relative standard deviations from 4.0% to 12.4 %). The proposed method was also applied to the analysis of these groups of pesticides in fresh grape sample purchased from the local markets of Lanzhou (China), while no residues of the selected pesticides were detected in the sample.  相似文献   

14.
Wine quality is evaluated by sensory attributes and physicochemical properties whose relationship is intensely investigated. This work aimed to analyze the physicochemical properties and sensory attributes of wines from Bordô and Isabel American grapes elaborated by a traditional and two novel winemaking processes: pre-drying and submerged static pomace. It was possible to observe significant differences between the samples in all physicochemical properties (P < 0.001), except in volatile acidity. Bordô and Isabel pre-drying wines presented the highest values of dry extract (43.00 and 33.66 g L?1) in comparison with the other wines which presented dry extract below 30 g L?1. Furthermore, pre-drying wines showed the highest phenolic content (1340.80 and 908.80 mg L?1) in comparison with static pomace (998.02 and 433.46 mg L?1) and traditional treatments (983.96 and 560.26 mg L?1). Sensory analysis showed significant differences between the samples in all attributes, except in appearance acceptance. Cluster analysis and multidimensional scaling was successfully applied and allowed to observe the relationship between physicochemical properties and sensory attributes. Total phenolic content and color indexes were associated with the appearance of wines, as well as alcohol content and acidity on aroma. The results also revealed the connection between dry extract and total and reducing sugars with the body of wines from innovative vinification. The flavor was associated with several physicochemical properties and also influenced the global acceptance of the samples. The innovative wines showed great acceptance in all sensory attributes, and the employment of these treatments on an industrial scale should be considered once providing wines with unique characteristics.  相似文献   

15.
16.
Ek?ikara (Vitis vinifera L.) is a poorly known native Turkish grape cultivar, which is being cultivated for thousands of years for table consumption, raisin, and grape molasses production. The aim of this study was to investigate the phenolic profile of whole berry, skin, and seeds of the cultivar and to determine the effect of harvesting year and altitude of the vineyard location. The grape samples were collected from two vineyards, located at 1000 and 1500 m of altitude in year 2014 while it was collected from 1500 m of altitude in year 2015. In addition to phenolic profile, antioxidant activity, total phenolic, anthocyanin, and tannin contents, and fatty acid profile of seed oil were also analyzed. In this study, anthocyanins, resveratrol, rutin, and isorhamnetin-3-glucoside were mainly found in skin while monomers and dimers of flavan-3-ols were present mainly in the seed. Altitude had a drastic effect on phenolic compounds as well as on the antioxidant activity of whole berry, skin, and seeds.  相似文献   

17.
18.
In industrialized countries, the epidemiology of infec- tious diseases with indirect transmission through water and foodstuffs has undergone considerable changes over the past decades with the almost total disappearance of some traditional pathogen microo…  相似文献   

19.
《Journal of dairy science》2022,105(5):4116-4127
Whether supplemental dietary β-carotene affects periparturient cows and vitamins A and E in cows when dietary vitamin A is adequate remains uncertain. Our objective was to assess the effect of β-carotene supplementation during the close-up dry period in a herd with adequate status of vitamins A and E but low in β-carotene. The study was conducted on a large commercial dairy farm in Indiana during early summer of 2015. Ninety-four multiparous Holstein cows were assigned to either control (CON; n = 47) or β-carotene (BC; n = 47) treatments. When locked in headgates each morning, each cow received a topdress of β-carotene (Rovimix, 8 g/d; provided 800 mg of β-carotene) or carrier from 21 d before expected calving until calving. Blood samples were collected at 21 ± 1 d (mean ± standard deviation) before expected calving (before treatments began), 7 ± 1 d before calving, immediately following parturition, and 7 ± 1 d postpartum. Blood serum was analyzed for vitamins A and E, β-carotene, cholesterol, and other metabolites and enzymes. Data were analyzed using the MIXED procedure in SAS (SAS Institute Inc.). Cows had low β-carotene concentrations (0.85 μg/mL) in blood serum before treatments began. Compared with CON cows, BC cows had higher overall mean concentrations of β-carotene (2.87 μg/mL vs. 0.73 μg/mL) and retinol (165 vs. 143 ng/mL). Cows fed BC had lower α-tocopherol in serum than cows fed CON (2.26 vs. 2.46 µg/mL). Cows fed BC had lower peak milk than cows fed CON (50.9 vs. 55.3), but total lactation milk yield did not differ significantly. No effects of BC were observed on days to conception (100 d) or times bred (2.4). Treatments did not affect incidences of ketosis, retained placenta, displaced abomasum, off feed, lameness, footrot, mastitis, or metritis. In conclusion, in pregnant cows already receiving adequate vitamin A but with low serum β-carotene concentration, supplementation of β-carotene increased concentrations of β-carotene and vitamin A in blood serum, but did not affect production, reproduction, or health.  相似文献   

20.
In this study the feasibility of a LLE–GC–EI-MS method for the analysis of 43 phenolic acids belonging to different chemical structure families which have been described in the literature as microbial-derived metabolites after consumption of dietary polyphenols was proved. In addition, the method was applied for the characterisation of phenolic metabolites resulting from the incubation, in anaerobic conditions, of a commercial grape seed extract (GSE) and their corresponding flavan-3-ol monomeric (GSE-M) and oligomeric (GSE-O) fractions with human faeces from healthy volunteers (n = 3). The method showed average values of repeatability and reproducibility of 5.0% and 6.3%, respectively, adequate and low detection (1.8–30.8 μg L−1) and quantification limits (6.0–102.8 μg L−1) and good recovery values (95%, as average value). A total of 27 phenolic acids were identified in the faecal solutions after incubation with the grape seed extracts. In general, faecal samples incubated with GSE and GSE-M (monomeric fraction) yield a higher formation of phenolic acids compared to the samples incubated with the oligomer fraction (GSE-O).  相似文献   

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