Effect of postharvest storage temperatures on the quality parameters of pistachio nuts

Abstract

Arena E., Ballistreri G., Fallico B. (2013): Effect of postharvest storage temperatures on the quality parameters of pistachio nuts. Czech J. Food Sci., 31: 467-473.Pistachios from Italy and Turkey were stored at different temperatures (10, 20, and 30°C) and the moisture of the pistachios, the free fatty acids (FFA) content, the peroxide value, and triacylglycerols (TGs) composition of the extracted oils were evaluated. The content of FFA decreased during storage at 10°C and increased at 20 and 30°C. No differences between the peroxide values were found during storage at 10°C. A significant increase in the peroxide values was observed after 20 days at 20°C and 5 days at 30°C in both the Italian and Turkish samples. The main TGs found in the pistachio oil of both origins were OLO, OLL, OLP, LLL, LLP, OOP, OLLn, and OOO; these accounted for approximately 85% of the total TGs content. A decrease was observed in the amounts of TGs esterified with polyunsaturated fatty acids, such as LLP, OLP, LLL and OLL, and an increase of the relative amounts of TGs with monounsaturated and saturated fatty acids, such as OOO and OOP, with the increasing storage time and temperatures in both samples.

Drying and decontamination of raw pistachios with sequential infrared drying, tempering and hot air drying

“…However, the FFA values of pistachios dried with IR heating for 1 and 2 h followed by tempering and hot air drying were not significantly different from each other, nor from the FFA values of samples dried with hot air only. The FFA values of the kernels after treatment in our study were comparable with that of 0.6% for sundried pistachios (Arena et al, 2013) and that of 0.27 -0.30% of pistachio nut cream containing 5-15% of pistachio nuts (Gamli and Hayoglu, 2012).…”

“…Longer periods of IR drying and tempering increased the PV as the oxidation of oil increases at higher temperatures (Kashaninejad et al, 2003). Greater PVs (5)(6)(7) Meq/kg) than those reported here were measured for raw walnut oils of three different varieties grown in New Zealand (Akbas and Ozdemir, 2006). Most importantly, the pistachios dried with the SIRHA technology had PVs less than 2.54 Meq/kg, which is lower than the nut industry specification (Almond Board of California), which states that the PV of fresh almond oils be less than 5.0 Meq/kg.…”

Lipid Oxidation Kinetics of Pistachio Powder During Different Storage Conditions

“…Various varieties of this nut has different tastes and flavors and its annual production in 2012 in three major producing countries (Iran, USA and Turkey) were close to 472,000, 231,000 and 150,000 metric ton, respectively (FAO ; Arena et al . ). Lipid oxidation of pistachio due to the seasonal weather variations (temperature and relative humidity) reduces its quality and shelf life.…”

Qualitative analysis of enzyme-assisted traditionally extracted shea butter from different pretreated shea kernel substrates

“…Chemicals unlike enzymes are harsh and unspecific in their attack of chemical bonds following the principle of dissolution and this can result in the formation of more saturated fats or FFAs. In addition, FFA increases with increasing temperature (Arena et al, 2013). The FFA was lowest in shea butter from raw kernels (RASK) by enzyme-assisted extraction and lowest in the butter from RASK from the other methods of extraction: 1.85% by the traditional method and 3.85% by solvent extraction method (Table 3).…”