Advancements and Impacts of Cold Plasma Technology on Dried Nuts and Related Products
In this review, various dried nuts such as almonds, pistachios, peanuts, walnuts, hazelnuts, mixed nuts, and others were subjected to different cold plasma (CP) techniques under varying processing parameters (e.g., voltage, current, frequency, time). The review examines the impact of these treatments on microbial reduction, sensory attributes, and physicochemical properties of the dried nuts. The results showed that CP treatment led to a 1–5 log reduction in microbial species on the surfaces of almond slices, pistachio nuts, peanuts, dried walnut kernels, and mixed nuts. While the peroxide value of the dried nuts remained largely unchanged, a slight increase was observed in peanuts, pistachios, and mixed nut snacks, accompanied by an improvement in antioxidant capacity. The texture of almond slices became harder, while the texture of other dried nuts remained unchanged. There were no significant alterations in the original color, flavor, or appearance of the dried nuts. The CP treatment significantly reduced the levels of toxin-releasing aflatoxins in the dried nuts. The moisture content, which is linked to microbial activity, was significantly decreased. CP also notably enhanced the water-holding capacity in some dried nut products, minimized insect/pest damage, and reduced the allergenicity (Ara h1 and Ara h2) of peanuts and cashew nuts.
https://doi.org/10.1111/jfpe.70080
A meta‐analysis of the effects of ultrasonic pretreatment on the characteristics of dried fruits and vegetables
Parameter selection in ultrasonic pretreatment is closely related to the quality of dried fruits and vegetables, so it is essential to investigate the impact of various parameters of ultrasonic pretreatment on the product quality. In this paper, data from 67 relevant literatures were collected to evaluate the effects of ultrasonic pretreatment on dried fruits and vegetables through meta-analysis. Overall, the findings indicated that ultrasonic pretreatment could shorten drying time, reduce hardness and improve color appearance of dried products. Subgroup analysis showed that high power ultrasound (P ≥ 300 W) could increase total phenol content and antioxidant activity of dried fruits and vegetables. Additionally, applying short-duration ultrasound (t < 15 min) increased antioxidant activity, while medium-duration ultrasound (15 min < t < 30 min) simultaneously enhanced flavonoid content and antioxidant activity. In summary, the application of ultrasonic pretreatment has a positive impact on processing high quality dried fruits and vegetables and obtains better-quality products in a shorter time compared to direct drying technology. https://doi.org/10.1111/jfpe.14689