A perspective on production and qualify of argentinian nut oils

Abstract

Nuts arerecommended constituents of the daily diet, although their real intake differs remarkably. In particular, they are part of healthy diets such as the Mediterranean diet. In the traditional Mediterranean population, mortality rates from coronary heart disease and cancer are low (Simopoulos, 2001). Emerging proofs indicate that nuts may be a source of health promoting compounds that elicit cardioprotective effects (Kris-Etherton et al., 1999).Nuts are crops of a high economic interest for the food industry. Nut fruits contain high levels of oil (50 - 70%) and they are consumed fresh, toasted or salted, alone or in other edible products. Among the by-products of nuts industry, in general, the oil has not yet obtained popularity, although it has been demonstrated that its consumption has a lot of nutritional benefits. The composition of nuts oils from different geographic origins have been reported extensively. Their major constituents are triglycerides, in which unsaturated fatty acids are present in high amounts. The presence of other bioactive minorcomponents, such as tocopherols and phytosterols, has been also documented. A major goal in nuts oils production is to find an appropriate method to recover oil from the seeds. To get high quality virgin oils, the process includes the selection of the fruits, the conditions of their transport and storage, the choice of the steps of the mechanical processing and finally the control of the storage and packaging conditions of the virgin oils. In recent years, there has been a resurgence of interest in the use of continuous, mechanicals crew-presses to recover oil from oil seeds. Although screw pressing will not extensively replace solvent extraction in commodity oilseeds - because it recovers a lower proportion of oil; in the case of new specialty edible oils, screw pressing provides a simple and reliable method of processing small batches of seed. Moreover, mechanical pressing oil extraction is technically less extensive and less labor-intensive than the extraction solvent method. The safety and simplicity of the whole process is advantageous over the more efficient solvent extraction equipment. Furthermore, materials pressed outgenerally have better preserved native properties, end products are free ofchemicals and it is a safer process.