Effect of the skin contact on the Aroma composition of the must of the white Emir grape variety [Kabuk Maserasyonunun Beyaz Emir Üzümünden Eide Edilen Şiranin Aroma Maddeleri Bileşimine Etkisi]

The effect of the skin-contact on the composition of free and glycosidically bound aroma components of the must of Vitis vinifera cv. Emir was investigated. Aroma components were analysed by GC-MS. Seventeen free (3 six-carbon alcohols, 2 terpenols, 2 alcohols, 5 acids, 3 phenols, 2 C-13 norisoprenoids) and 30 bound aroma components (3 six-carbon alcohols, 4 terpenols, 5 alcohols, 5 acids, 9 phenols, 4 C-13 norisoprenoids) were identified. The skin-contact treatment increased amounts of free and glycosidically bound aroma components, potassium, total phenolic compounds and the browning index and the pH value, whereas it decreased the amount of total acidity

The effects of storage temperature on the chemical composition of hop pellets

The effects of storage temperature on the composition of hop pellets of the varieties Brewers Gold, Efes Aroma, Galena, Northern Brewer and Saaz were studied. The hop pellets were stored at 3°C and room temperature for 6 months in the dark. Chemical analyses showed that there were substantial losses of alpha- and beta-acids, soft resins and hop oil in all hop varieties stored at room temperature. These hop varieties showed a significant increase in hard resins at room temperature storage. Storing these varieties at 3°C did not stop but slowed down these detrimental changes in hop composition. Changes in hop composition during storage were also dependent on the variety of hops used. © 2001 Elsevier Science Ltd

The effect of yeast strain, immobilisation, and ageing time on the amount of free amino acids and amino acids in peptides of sparkling wines obtained from cv. dimrit grapes

In this study, the influence of yeast strain, immobifisation, and ageing time with yeast were examined in relation to the amount of free amino acids and amino acids in the peptides of wines. Free and immobifised Saccharomyces bayanus and Saccharomyces cerevisiae yeasts were used in sparkling wine production. Samples from the base wine and sparkling wines were taken at 20, 40,90, 180, 270 and 365 days of ageing with yeast. It was observed that the majority of differences between wine samples in terms of the amount of free amino acids and amino acids in peptides were due to ageing time. The amount of total free amino acids in wine made with Saccharomyces cerevisiae was higher than in that made with Saccharomyces bayanus. In addition, no differences were observed between free and immobifised yeast in terms of amino acids and amino acids in peptides

Effect of cold maceration treatment on anthocyanins in red wine production of öküzgözü grapes [Öküzgözü üzümlerinden kırmızı şarap üretiminde soguk maserasyon uygulamasının antosiyaninler üzerine etkisi]

In this study, anthocyanin compounds of wines made from cv. Öküzgözü and effects of by cold maceration on the anthocyanin profiles of these wines were investigated. Anthocyanin composition was detected by high performance liquid chromatography (HPLC) coupled with diode array detector. Fourteen different anthocyanins, including five glucosides, five acetyl glucosides, and four coumaroyl glucosides were identified and quantified. Total concentration of these compounds was 284.15 mg l-1 for cold maceration wines and 243.62 mg l-1 for control wines. Malvidin-3- glucoside was the most abundant and cyanidin-3-glucoside was minor anthocyanins in both wines. Total colour intensity, phenolic and tannin content of wines produced with cold maceration were clearly higher than control wines. Based upon sensory analysis, the wines obtained from cold maceration had higher colour, flavour, body, astringency aftertaste and harmony character than that the one produced from traditional maceration. © Ankara Üniversitesi Ziraat Fakültesi

Effect of bottle colour and storage conditions on browning of orange wine

PubMedID: 12017992We investigated the effect of bottle colour, storage temperature and storage time on the browning of orange wine. Kozan orange variety was used for the production of wine. The fermentation was performed spontaneously at 20°C. The wine was bottled in three differently coloured bottles: clear white, green and brown. Then each was divided into two parts: one part was stored at 13-14°C in the cellar and the other at 23-26°C in the laboratory for 150 days. During the storage, browning index and ascorbic acid content of the wines were measured at day 0, 75 and 150. The results showed that the use of brown bottles and the short-time storage reduced the browning in orange wines, however, storage at two different temperatures did not significantly affect the browning index

Effect of use of pure yeast culture (Saccharomyces cerevisiae-K1) on aromatic compounds of emir wine [Emir üzümünün şaraba i·şlenmesinde saf maya (Saccharomyces cerevisiae-K1) kullaniminin aroma maddeleri üzerine etkisi]

In this study, aroma compounds of the wines obtained from white Emir grapes grown in Nevşehir-Ürgüp region by spontanous fermentation and by use of pure culture of "Saccharomyces cerevisiae-K1" were investigated. Aroma compounds were extracted by Amberlit XAD-2 resin and were eluted by pentan/dichloromethane (2/1) solvent and then analysed by gas chromatography and identified by gas chromatography mass spectrometry (GC-MS). A comparison of the aroma compounds of the wines obtained by spontanous fermentation and by use of pure culture showed that the latter contained higher amount of high alcohols and carbonyl compounds, and lower amount of volatile phenols, esters being at the same level. Additionally, it was found that 4-vinylphenol and 4-vinylguaiacol formed by "Saccharomyces cerevisiae-K1" was very low because of the poor decarboxylase activity of this strain. Statistical analysis of sensory evaluation showed that there was a significant difference between the wines. However, the difference between the wines in terms of the preference of the panel members was not significant

A traditional Turkish lactic acid fermented beverage: Shalgam (Salgam)

Shalgam is a traditional lactic acid fermented beverage in which black carrot, bulgur flour, sourdough, salt, turnip, and water are used for production. It is a red coloured, cloudy and sour soft drink mainly consumed in southern Turkey, however, its consumption is currently increasing in other parts, as well. Shalgam is produced on an industrial scale. Although there is no standard production technique in industry, it could be stated that there are two methods for shalgam production: the traditional method and the direct method. The traditional method comprises sourdough fermentation and carrot fermentation. In the direct method, however, the sourdough fermentation is omitted and only the carrot fermentation is applied. During fermentation, mainly lactic acid bacteria give shalgam its typical taste and flavour by producing lactic acid, ethanol, and some other organic compounds. This article reviews some aspects of shalgam production

Influence of Saccharomyces cerevisiae strains on fermentation and flavor compounds of white wines made from cv. Emir grown in Central Anatolia, Turkey

PubMedID: 12080424The effect of inoculation with selected Saccharomyces cerevisiae strains was studied on fermentation and flavor compounds of wines made from Vitis vinifera L. cv. Emir grown in Central Anatolia, Turkey. Flavor compounds were analysed and identified by GC-FID and GC-MS, respectively. The total concentrations of flavor compounds did not increase with the addition of indigenous and commercial wine yeasts, but differences were noted in individual volatile compounds. Cluster and factor analyses of flavor compounds also showed that wines produced were different depending on the wine strain used. Wines were completely fermented to less than 1.4 g/l residual sugar. Yeasts other than S. cerevisiae survived longer than previously reported. Inoculation with selected strains increased the ethanol level

Contribution by Saccharomyces cerevisiae yeasts to fermentation and flavour compounds in wines from cv. Kalecik karasi grape

The effect of indigenous and commercial S. cerevisiae yeasts on fermentation and flavour compounds of wines was examined in pasteurised grape juice. The flavour compounds were analysed and identified by GC-FID and GC-MS, respectively and in general, the amounts of these volatiles were increased by the use of both indigenous and commercial yeasts. The levels of isoamyl alcohol, isoamyl acetate, ethyl octanoate and ethyl deconoate exceeded flavour thresholds. All grape juices were fermented to dryness. Selected yeasts produced higher ethanol concentrations compared to spontaneous fermentations