Determination of sustainable use potential of product extracted from pistachio (Pistacia vera L.) wastes

The soft outer shell produced during the processing of pistachios is largely discarded onto fields or dumped into water sources without undergoing any treatment, resulting in significant environmental problems. In order to explore the potential for sustainable utilization of processing industry waste and identify possible areas of use, samples of the uzun variety of pistachio soft outer shell waste (AFYDK-1) and shell-intact samples (AFYDK-2) were obtained from the province of Şanlıurfa and subjected to analysis. Essential oil content, bioactive content, antioxidant activities of volatile oils, amino acid and fatty acid contents, as well as moisture, dry matter, protein, oil, and ash values were determined in order to characterize the samples. The study revealed that the essential oil content and its main component in AFYDK-1 samples was α-pinene (18.46%), while in AFYDK-2 samples it was α-pinene (31.31%). The radical scavenging effect (IC50) values calculated from essential oil acids were determined to be 18.20 mg/L for AFYDK-1, 4.09 mg/L for AFYDK-2, and 6.31 µg/L for the synthetic antioxidant BHT. The dry matter content for AFYDK-1 and AFYDK-2 was found to be 30,99±0,60 and 12,31±0,52, respectively; protein contents were 10,81±0,44 and 11,93±0,14, respectively; oil contents were 9,23±0,53 and 6,94±0,60, respectively; and ash contents were 14,65±0,16 and 14,50±0,95, respectively. The results of the study suggest that the products obtained could be beneficial in various industrial processes and products. The findings also indicate that the use of pistachio shells could reduce the harmful effects on the environment. This study is considered to be an important step in the sustainable utilization of local resources and waste management.