Pistachio Hull Extract as a Practical Strategy to Extend the Shelf Life of Raw Minced Beef: Chemometrics in Quality Evaluation

The agricultural processing industry produces a notable quantity of by-products rich in bioactive compounds, which can be exploited for agri-food applications. From pistachio industrial processing, pistachio’s hull is one of the major by-products. This work aimed to evaluate the potential of pistachio hull, as a potential source of natural antioxidant, to preserve the meat quality. Here, we investigated the impact of aqueous pistachio hull extract (PHE) at 0.156% (PHE1), 0.312% (PHE2), and 0.625% (PHE3) on the quality of raw minced beef meat stored for 14 days at 4°C. At the end of storage, mesophilic total viable plate, psychotropic and Enterobacteriaceae counts, showed significantly lower ( P < 0.05 ) microbial count in PHE samples. PHE3 revealed a powerful inhibitory effect on lipid/protein oxidation, and sensory characteristics were positively ( P < 0.05 ) affected. Principal component analysis and heat map indicated complex and close synchronized relations among lipid/protein oxidation processes, microbial loads, and sensory attributes. Obtained results using univariate and multivariate statistical analysis underlined the importance of using different mathematical approaches, which are complementary to each other and could provide considerable information about the minced beef meat treated by PHE. Therefore, compared to synthetic antioxidants, PHE could be a clean-label alternative that can protect and enhance the quality of meat products.

The effect of storage on some chemical and microbial properties of apricots dried with a combined solar energy assisted air and hot air assisted radio frequency drying system

Innovative combined solar energy assisted air and hot air assisted radio frequency drying system was used to dry unsulphured, sulphured (1 kg/ton and 2 kg/ton sulphur) and pistachio hull extract treated apricots. Unsulphured and sulphured apricots dried under sun were used as the control samples. The effects of different storage temperatures (5, 20 and 35oC) on residual sulphur content, β-carotene and microbial stability characteristics of dried apricots were studied. Also, the effect of storage temperature on the total phenolic content of dried apricots pre-treated with pistachio hull extract was investigated. The obtained results showed that the loss of sulphur and β-carotene was less in the products stored at 5oC compared to the products stored at 20 and 35oC. Sulphur treatment significantly inhibited the loss of β-carotene during storage. The maximum decrease in phenolic content of dried apricots pretreated with extract, was observed in samples stored at 20°C. In addition, extract treatment provided an advantage in terms of storage considering the microbial quality. The combined drying system caused less sulfur loss compared to sun drying.