Postharvest Biology and Technology
Samane Mollaei; Seyed Hossein Mirdehghan; Mahdi Shariat; Fatemeh Nazoori
Abstract
Purpose: This study evaluated the effects of cold plasma (CP) treatment using argon (Ar), nitrogen (N₂), and oxygen (O₂) gases at two voltages (5 and 8 kV) on the postharvest quality and shelf life of fresh in-hull pistachio (Pistacia vera L.) during cold storage. Research Method: Treatments were ...
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Purpose: This study evaluated the effects of cold plasma (CP) treatment using argon (Ar), nitrogen (N₂), and oxygen (O₂) gases at two voltages (5 and 8 kV) on the postharvest quality and shelf life of fresh in-hull pistachio (Pistacia vera L.) during cold storage. Research Method: Treatments were applied, and the samples were stored at 4°C for 25 and 50 days. Key parameters, including decay index (DI), water activity, total phenolic content (TPC), total flavonoid content (TFC), total chlorophyll content, electrolyte leakage (EL), and sensory attributes, were assessed. Findings: Decay index (DI) measurements demonstrated that CP treatments significantly inhibited microbial spoilage, and argon-CP reduced decay by up to 40% compared to untreated controls. Water activity declined from 0.957 in the controls to as low as 0.952 in the argon-treated samples, indicating reduced free water available for microbial growth. Biochemical analyses revealed that total phenolic content (TPC) increased the most under nitrogen-CP (0.485 mg GAE/100 g at 50 days vs. 0.350 mg in controls). Total chlorophyll content was highest in N₂-treated pistachios (2.96 g kg⁻¹), and electrolyte leakage (EL), an indicator of membrane integrity, was lowest in argon-CP samples (74.82% vs. 88.67% in controls), reflecting reduced cellular damage. Sensory analysis confirmed that CP-treated samples, particularly those treated with Ar, improved texture, taste, color, and aroma. Research limitations: This study was limited to laboratory-scale conditions and storage durations. Originality/Value: This research provides new insights into non-thermal postharvest preservation of pistachios and highlights cold plasma, particularly Ar-treatment, as a practical, chemical-free method to enhance quality and extend shelf life.
