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Aqueous enzymatic extraction of corn germ oil was investigated. By applying hydrothermal pretreatment of corn germ, it was possible to inactivate native enzymes present in the germ and to loosen its structure. The corn was then ground and treated with enzymes. After the oil had been released by the enzyme reaction, it was separated by centrifugation. The quality of oil obtained by enzymatic extraction (Pectinex Ultra SP‐L at 37°C, pH 5.2, for 6 h) was good. The oil had 1.5% free fatty acids; a total content of oxidation product value of 8.1; light yellow color (AOCS photometric color, 12.7; dominant wavelength λD=575 nm); 0.022% phosphatides; 1350 mg/kg total tocopherol; and an oxidative stability value (Rancimat test, 100°C) of 14.6 h.

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Physico-chemical properties of milled rice grains of 13 japonica varieties were evaluated. The rice varieties differed in appearance. One sample had long grains (6.61 mm), two had short grains (5.27-5.32 mm) and the rest had grains of medium length (5.52-6.55 mm). The shape (length/width) of grains varied from bold (1.58-1.9) to medium (2.06-2.37). The protein content was high in all samples (7.82 to 9.72% on dry mass). Almost all, with exception of one cultivar (Osogovka), which had intermediate amylose content (23.3%), were low amylose varieties (12-19.4% amylose). Their minimum cooking time varied from 17.5 to 22.5 min. Significant correlations (P < 0.05) were established between some physico-chemical characteristics of evaluated rice culti-vars. Elongation during minimum cooking time was correlated with protein content (r = 0.6899), shape (-0.7137), thickness (0.7234) and width (0.9134) of grains. The rice flour paste viscosity correlated significantly with shape (0.6148) and length (0.7353) of grains. On the basis of the established results, it was concluded that appearance of milled rice could be used as indicator for predicting gelatinization behavior: elongation ratio (length after minimum cooking time/length of the grains) of the rice grains and viscosity of rice flour during cooking. 3 Corresponding Results from this research constitute a useful tool to predict the gelatini-zation behavior of milled grains and flour of japonica rice varieties, on the basis of grain appearance. The appearance is critical in acceptability of rice varieties by the consumers. The possibility to predict rice grain behavior during cooking on the basis of its appearance could be an additional attribute or market value for consumer choice. The results could be used in selection of rice variety for rice grits or flour production and use in special applications.

Peppermint, creeping thyme, and sage herbs, as well as yarrow flowers were extracted with supercritical and liquid carbon dioxide at 9-13 MPa and 25-60?C. Two extraction periods were distinguished except in the case of thyme extraction. Almost pure essential oil was extracted in the first, fast period. The extraction was retarded in the second period controlled by essential oil-matrix interaction, and waxes and water prevailed over the essential oil in the extract. To estimate the effect of essential oil-vegetable oil interaction during the extraction of essential oils from seeds, the limonene + vegetable oil + CO2 equilibrium was investigated using thermodynamic modeling. Changes in the composition of the essential oil in the extracts are demonstrated on the example of sage oil. Compared to hydro distillation, the extracts contained less monoterpenes, the most volatile components, because the separation of the extract from gaseous ??2 in the cold trap was incomplete. The yield of sesqui- and di-terpenes in the extracts, however, was higher than their yield by hydrodistillation. The extraction of sage essential oil was most efficient at 13 MPa and 50?C, when the yield of diterpene manool was more than two times higher than its yield by hydrodistillation.

The evolution of individual anthocyanins during vinifi cation of Merlot and Pinot Noir grapes was studied using two different winemaking procedures for each grape variety. Additionally, the effect of the applied vinifi cation on the anthocyanin composition of the obtained wine at the end of maceration and wine aged 6 months was investigated and compared with the anthocyanin patterns of the original grape. The dynamics of the extraction process was monitored daily during maceration by analysing the anthocyanins in the must using HPLC. The results showed that the anthocyanin composition of young wines was different from that of the grapes. The proportions of malvidin-3-glucoside and malvidin-acetate were higher in wines than in the grape skins, but this was not the case for malvidin coumarate. Application of different vinifi cation procedures to the same raw material resulted in wines with similar anthocyanin patterns. However, the anthocyanin profi les changed with the ageing of the wines.

Wines of three different grape varieties, Vranec, Cabernet Sauvignon and Merlot were examined for their characterisation in terms of anthocyanin and chromatic profiles, total polyphenols and antioxidant potential. Total, monomeric, polymeric and copigmented anthocyanins were determined by spectrophotometry and the individual anthocyanin compounds were quantified using HPLC-DAD. Chromatic profile was evaluated according to colour density, hue, % red, % blue, % yellow and brilliance (% dA). The established data were submitted to analysis of variance and principle component analysis in order to evaluate their potential for differentiation of wines according to variety and vintage. Vranec wines have shown distinctive characteristics, with the highest content of anthocyanins and values of colour intensity, % red and % dA, compared to the other two studied varieties. The content of petunidin-3-glucoside, peonindin-3-glucoside and anthocyanin acetates were established as possible markers for differentiation of Vranec wines from Cabernet Sauvignon and Merlot wines. However, none of the assayed parameters could be used for differentiation of Cabernet Sauvignon from Merlot wines. It was observed that wine age limits successful classification of the wines by variety according to anthocyanins. The chromatic parameters allowed distinguishing of young (aged up to 1 year) from old Vranec wines