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The compositon of olive oil results from a multivariate interaction in which genotype, environment, and agronomic-dependent factors are involved. The genotype controls genetic traits accounting for the rate pattern of fruit growth, oil accumulation in mesocarp cells and fruit ripening, while the genotype x environment interaction changes the rate of fruit growth, oil accumulation and fruit ripening pattern. The latter accounts for large changes in oil composition and sensorial features. The influence of genotype is linked to differences in the fruit growth and ripening patterns, though all those factors that may have an influence on fruit size, flesh/pit ratio and relative growth rate have a lower and more erratic influence on the olive oil composition. The genotype is the principal source of sensorial differences and this has been proved for most of the cultivars, giving them a specific role in gastronomy. The influence on olive oil composition of environmental factors, such as temperatures during fruit growth and ripening or water availability, may also be a function of changes in the fruit growth and ripening patterns and of the oil accumulation rate pattern. Some facts have been generally recognized, such as the changes of saturated vs insaturated fatty acids ratio in relation to temperature and latitude or the progressive reduction of polyphenols content in the oil along with fruit ripening or with the increase of water availability. Crop load influences the fruit ripening rate pattern and the rate pattern of oil accumulation and this may account for differences in oil composition, related to polyphenols and fatty acid content. This review covers different sources of variability of olive oil composition and overall quality, such as genotype, environment, bearing capacity, stage of fruit ripening during harvest and cultural management (irrigation, fertilization, harvest). None of these aspects can be underestimated in order to reduce the site- and year-dependent fluctuactions of olive oil quality of specific genotype.

Recent approaches about food quality have stressed the social processes by which “quality conventions” prevailing on the market are achieved. The present work investigates these conventions on the supply side, focusing on the “styles” characterizing the management of a group of firms. More specifically, the research analyzes a group of oil-press plants localized in Molise, an Italian region the name of which is also the “brand-name” of a PDO recently registered by EU. In the first part the essay outlines the scenario of both olive oil market and local context. In the second section the paper shows the results of a direct survey. Applying factorial analysis to the data collected in the survey, four main “quality factors” were identified: safety and health; localization and scale; product differentiation; technological heritage. On the basis of these factors it was possible to point out three main styles characterizing the sample firms: the “endogenous”, the local, and the “fordistic” one.

Several wild yeast strains isolated from spontaneous must fermentation were tested for use in wine-making. The ability of Saccharomyces cerevisiae GR7 and GR3 to produce a regular fermentation process, complete fermentation, and produce ethanol and low volatile acidity at both 12 degrees C and 20 degrees C indicate that both strains are promising as starter cultures in winemaking. The effect of wild yeast strains on the relative composition of several volatile compounds in wines fermented at 12 degrees C or 20 degrees C was also studied. Pinot Grigio must fermentation was carried out using selected yeast strains. In addition, Debina and Roditis wines were made by spontaneous must fermentation. Experimental wines were analyzed for volatile compounds using solid phase microextraction and GC-MS analysis. In all wines fermented at 12 degrees C, most acetate esters, ethyl esters, higher alcohols and fatty acids were lower than in those fermented at 20 degrees C. Food Science and Technology Research