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Evaluation of colour parameters and antioxidant activities of fruit wines

The evaluation of oenological colorimetric indexes, CIELAB parameters, total phenols and antioxidant activities has been studied in different fruit wines made from black mulberry, blackberry, quince, apple, apricot, melon, red raspberry, bilberry, sour cherry and strawberry. The highest value of antioxidant activities and total phenolic contents were determined in bilberry, blackberry and black mulberry wines (61.80%, 1161 mg/l gallic acid equivalents; 60.00%, 1232 mg/l gallic acid equivalents; 58.10%, 1081 mg/l gallic acid equivalents), respectively. The highest values for A420 nm, A520 nm, A620 nm, the proportion of blue, wine colour, wine total colour of pigments, wine polymeric pigment colour and K-K values logarithmic colour intersity) were determined in bilberry fruit wine. Positive correlation was found between antioxidant activities and total phenols (r=0.958, P = 0.001). The results of grouping of different parameters in n-dimensional space with different fruit wines demonstrated the importance of bilberry, blackberry and black mulberry wines as natural antioxidants and colourants.The evaluation of oenological colorimetric indexes, CIELAB parameters, total phenols and antioxidant activities has been studied in different fruit wines made from black mulberry, blackberry, quince, apple, apricot, melon, red raspberry, bilberry, sour cherry and strawberry.The highest value of antioxidant activities and total phenolic contents were determined in bilberry, blackberry and black mulberry wines (61.80%, 1161 mg/l gallic acid equivalents; 60.00%, 1232 mg/l gallic acid equivalents; 58.10%, 1081 mg/l gallic acid equivalents), respectively. The highest values for A420 nm, A520 nm, A620 nm, the proportion of blue, wine colour, wine total colour of pigments, wine polymeric pigment colour and K-K values logarithmic colour intersity) were determined in bilberry fruit wine. Positive correlation was found between antioxidant activities and total phenols (r=0.958, P = 0.001). The results of grouping of different parameters in n-dimensional space with different fruit wines demonstrated the importance of...

Protection capacity against low-density lipoprotein oxidation and antioxidant potential of some organic and non-organic wines

Current research suggests that phenolics from wine may play a positive role against oxidation of low-density lipoprotein (LDL), which is a key step in the development of atherosclerosis. Considering the effects of different wine-making techniques on phenols and the wine consumption preference influencing the benefical effects of the product, organically and non-organically produced wines were obtained from the grapes of Vitis vinifera origin var: Carignan, Cabernet Sauvignon, Merlot, Grenache, Columbard and Semillon. Levels of total phenols [mg/l gallic acid equivalents (GAE)], antioxidant activity (%) and inhibition of LDL oxidation [%, inhibition of diene and malondialdehyde (MDA) formation] were determined. Some phenolic acids (gallic acid, p-hydroxybenzoic acid, syringic acid, 2,3-dihydroxybenzoic acid, ferulic acid, p-coumaric acid and vanillic acid) were quantified by high-performance liquid chromatography equipped with an electrochemical detection carried at +0.65 V (versus Ag/AgCl, 0.5 μA full scale). The highest concentrations of gallic, syringic and ferulic acids were found in organic Cabernet Sauvignon; 2,3-dihydroxybenzoic acid in organic Carignan and p-coumaric and vanillic acids in non-organic Merlot wine. High levels of antioxidant activity (AOA), inhibition of LDL oxidation and total phenol levels were found in non-organic Merlot (101.950% AOA; 88.570% LDL-diene; 41.000% LDL-MDA; 4700.000 mg/l GAE total phenol) and non-organic Cabernet Sauvignon (92.420% AOA; 91.430% LDL-diene; 67.000% LDL-MDA; 3500.000 mg/l GAE total phenol) grape varieties. Concentrations of some individual phenolic constituents (ferulic, p-coumaric, vanillic) are correlated with high antioxidant activity and inhibition of LDL oxidation.The best r value for all examined characteristics was determined for gallic acid, followed by 2,3-dihydroxybenzoic, syringic, ferulic and p-coumaric acids. Negative correlation of vanillic with MDA and p-hydroxybenzoic acid with LDL were confirmed by principal component analysis (PCA) analyses. Red wines display a higher antioxidant activity (81.110% AOA) than white ones (19.512% AOA). The avarage level of LDL inhibition capacity in red wine was determined as 87.072% and for the white as 54.867%.

Influence of different maceration time and temperatures on total phenols, colour and sensory properties of Cabernet Sauvignon wines

Maceration and fermentation time and temperatures are important factors affecting wine quality. In this study different maceration times (3 and 6 days) and temperatures (15 ℃ and 25 ℃) during production of red wine (Vitis vinifera L. Cabernet Sauvignon) were investigated. In all wines standard wine chemical parameters and some specific parameters as total phenols, tartaric esters, total flavonols and colour parameters (CD, CI, T, dA%, %Y, %R, %B, CIELAB values) were determined. Sensory evaluation was performed by descriptive sensory analysis. The results demonstrated not only the importance of skin contact time and temperature during maceration but also the effects of transition temperatures (different maceration and fermentation temperatures) on wine quality as a whole. The results of sensory descriptive analyses revealed that the temperature significantly affected the aroma and flavour attributes of wines. The highest scores for ‘cassis’, ‘clove’, ‘fresh fruity’ and ‘rose’ characters were obtained in wines produced at low temperature (15 ℃) of maceration (6 days) and fermentation.

Descriptive Analysis of Red Wines From Different Grape Cultivars in Turkey

A total of 15 red wines produced from 8 grape varieties were evaluated and profiled by quantitative descriptive analysis. The results of wine aroma characteristics demonstrated the following major descriptors for each wine type: grape juice, flowery (Cinsaut), flowery, dust (Calkarası), raisin, wet wood (Boğazkere), raisin, caramel (Cabernet sauvignon), raisin, dust (Gamay), cornel cherry, pineapple (Syrah), caramel, grape juice (Kalecık karası), and medicinal, caramel (Karasakız). Flavor profile of red wines revealed specific flavor descriptors for each wine type, namely: sour cherry, medicinal, grape juice (Cinsaut), medicinal, hot wood, grape juice (Calkarası), raisin, cornel cherry, dry apricot (Boğazkere), raisin, medicinal, plum (Cabernet sauvignon), sour cherry, tobacco, raisin (Gamay), cornel cherry, grass, pineapple (Syrah), sour cherry, green, wood (Kalecik karası), and sour cherry, medicinal (Karasakız).

Application of Artificial Neural Networks (ANNs) in Wine Technology

In recent years, neural networks have turned out as a powerful method for numerous practical applications in a wide variety of disciplines. In more practical terms neural networks are one of nonlinear statistical data modeling tools. They can be used to model complex relationships between inputs and outputs or to find patterns in data. In food technology artificial neural networks (ANNs) are useful for food safety and quality analyses, predicting chemical, functional and sensory properties of various food products during processing and distribution. In wine technology, ANNs have been used for classification and for predicting wine process conditions. This review discusses the basic ANNs technology and its possible applications in wine technology.

Descriptive Profiling of Flavor Attributes of White Wines From Different Grape Varieties

The aim of the present study was to determine the effect of using different grape varieties on the sensory flavor characteristics of Turkish white wines. 17 commercial white wines from 5 grape varieties (Emir-5, Narince-4, Semillon-4, Muscat-2, Chardonnay-2) of 2001 vintage, obtained from local market were analyzed by quantitative descriptive analysis. Graphical representation of the sensory profiles including aroma and flavor characteristics were provided as spider-web diagrams by plotting the mean values for the sensory descriptors. Least significant differences between wines for each descriptor were calculated by analysis of variance (ANOVA) using the SPSS program. It was observed that characteristics such as alcohol, sulphur, and raisin were present in the aroma and flavor of all wine varieties, while some characters seemed to be specific for wines produced from certain types of grapes (grape juice- Emir-1, 2, 3, 4; rose-Muscat-1,2; green plum-Semillon-1, 2; melon-Narince-3; banana- Chardonnay-1; tobacco- Chardonnay-2).

Changes of Phenolic Acids During Aging of Organic Wines

Grapes (Vitis vinifera L. origin var: Carignane, Cabernet Sauvignon, Merlot, Grenache, Columbard, and Semillon) were cultivated and processed according to accepted organic agriculture and organic wine techniques. Aged wines (5 years) were evaluated for changes of their phenolic acids. The highest reduction of gallic acid concentrations were determined in Cabernet Sauvignon (24.36 mg/L) and Carignane (16.00 mg/L) wines. The quantities of p-hydroxybenzoic acid decreased mostly in Carignane (22.47 mg/L) and Columbard (20.84 mg/L) wines. The decreases of syringic acid were dominant in Cabernet Sauvignon (2.34 mg/L) and Carignane (1.69 mg/L) wines. In the case of ferulic acid, the highest reduction was determined in Cabernet Sauvignon (3.97 mg/L) wines. The decreases of p-coumaric acid contents were the same and mostly in Merlot (1.06 mg/L) and Grenache (1.035 mg/L) wines. The principal component analyses results demonstrated the relations among aged wines produced from different grape varieties and their phenolic acids. The distribution of data was accumulated into two groups. The first group included total phenols, gallic acid, p-hydroxybenzoic acid, syringic acid, p-coumaric acid, and Merlot/Carignane/Grenache wines. The second one included ferulic acid and Cabernet Sauvignon wine.

Effect of blueberry tea on lipid and antioxidant status in children with heterozygous familial hypercholesterolemia: pilot study

Abstract Aim: The aim of the study was to determine whether 6-month regular ingestion of blueberry tea could improve the lipids and oxidative biomarkers in children with heterozygous familial hypercholesterolemia (HeFH). Materials & methods: Pulverized blueberry tea brewed for 5 min (PBTB5; 32 mg/kg/day anthocyanins) was consumed for 6 months by ten patients with HeFH (group A) and results were compared with group B (ten patients with HeFH who did not receive PBTB5). Lipids, lipid peroxidation products and antioxidative status were measured at baseline, 1 and 3–6 months on PBTB5, and after a washout period (12 months). Results: After 1 month of treatment, there was no significant difference in the lipids, peroxidation and antioxidative status between groups. Reductions in total and LDL-cholesterol in group A were found after 3 (p < 0.05) and 6 months (p < 0.01). After 6 months of treatment, HDL-cholesterol of group A increased (48.78%; p < 0.01). There were significant increases in antioxidants and decreases in lipid peroxidation products of group A at the end of 6 months. At the end of the washout period the difference between group A and B lipids, lipid peroxidation and antioxidative status did not reach statistical significance. Conclusion: PBTB5 had a positive effect on plasma lipid profiles and antioxidant status in children with HeFH when consumed daily and for a long time.