Compost supplementation with defatted pistachio meal in A. bisporus concerns mainly the quantitative parameters (size, texture, dry weight and protein). Based on the results obtained, this technique has greater potential of development for P. ostreatus commercial crops, basically due to expected increases in production, with a direct impact on benefits and crop profitability. © 2015 Society of Chemical Industry.

Pistachio is one of the preferred nuts worldwide due to the health benefits associated to its consumption. It contains 50–62% of oil that can be extracted with different methods: organic solvents, supercritical fluids, and pressure systems. The most common extraction methods to obtain virgin pistachio oils are the pressure methods (screw press or hydraulic press). Although slight variations can be found in the oil depending on the system used, the pistachio oil is characterized by the richness in unsaturated fatty acids. It also contains a high proportion of sterols compared to other nut oils, and exhibits a high antioxidant capacity. It can be used in many ways as a gourmet ingredient in the food industry and also in the cosmetic industry. Practical applications: Pistachio oil is a valuable product from the gastronomy point of view. Knowledge on the extraction process conditions may help to produce high quality oils with minimal losses in its nutritional value, and increase the organoleptic properties, maintaining the health benefits associated to its consumption. Changes in the extraction process conditions may originate changes in the organoleptic characteristics of pistachio oil. Thus, the modification of the extraction conditions may lead to the elaboration of different products that fit the consumers’ preferences.

Drying is an important operation in pistachio processing to ensure good quality. Study of drying parameters is important since they affect the quality, mainly in color, flavor and nutritional value. Hence, drying parameters could also affect pistachio oils. Pistachios of variety Larnaka were dried at different temperatures (room, 30, 50, and 70°C). Changes in physicochemical quality parameters, stability, and chemical composition of the extracted oils were evaluated. Sensory evaluation was also performed. An increase in the peroxide value was observed when pistachios were dried at 70°C or when screw press was used to extract the oil, remaining low in the rest of oils extracted with the hydraulic press. A similar pattern was observed for K 270 extinction coefficient. In addition, the oils from pistachios dried at higher temperatures (50°C, 70°C) showed an increase in polyphenol content and a decrease in stigmasterol. The oxidative stability was slightly higher when screw press was used. Changes in drying temperature and extraction system had no significant effects on fatty acid composition. Color sensory tests indicated a consumer preference for oils from pistachios dried at 70°C, which produced greenish oils. Pistachio oils with different characteristics are obtained depending on the drying temperature used, both of them acceptable by consumers.Practical applications Pistachios are considered nuts with the most nutritional value and a rich source of natural antioxidants. Drying is an important stage during pistachio processing, as it affects their oil fraction. The extraction system may also influence the characteristics of the final product. The combination of the drying temperature and extraction system may produce oils with different characteristics, which could be an interesting alternative in order to fit any consumer preferences.