Search

Light downconversion films can modulate incident light wavebands on crops, converting less utilised wavebands in an efficient way. In this experiment, red (conversion of green into red light wavebands), pink (conversion of UV and green into blue and red light but to a smaller degree than red film), and blue (conversion of UV into blue light) light downconversion films were used to cover blackberry plants throughout all phenological stages (from leaf emergence to fruit harvesting). The plants’ physiological and biometric performance, and fruit yield and quality were evaluated. Plants under blue and red films showed a higher net photosynthetic rate with +23.1% and +14.9%, respectively, and a higher stomatal conductance with +56.0% and +23.6%, respectively, with respect to controls, maintaining stability across stages, except for a decrease under the red film during fruiting. Both films significantly boosted the fruit yield, with the red film increasing the fruit number (+49.8%) and the blue film enhancing the berry shape (+10.7) and fresh weight (+36.6). Notably, no significant differences in nutraceutical quality, including total flavonoid and anthocyanin content, were observed. These findings suggest that light downconversion films, particularly red and blue films, can effectively enhance the photosynthetic performance and fruit production in blackberry plants without compromising the fruit quality. Future research on this topic should focus on balancing plant growth, fruit productivity, and enhancing fruit nutraceutical properties.

The growth of agricultural mechanization has promoted an increase in raspberry production, and for this reason, the best postharvest storage and processing techniques capable of maintaining the health beneficial properties of these perishable berry fruits have been widely studied. Indeed, raspberries are a rich source of bioactive chemical compounds (e.g., ellagitannins, anthocyanins, and ascorbic acid), but these can be altered by postharvest storage and processing techniques before consumption. Although there are clear differences in storage times and techniques, the content of bioactive chemical compounds is relatively stable with some minor changes in ascorbic acid or anthocyanin content during cold (5 °C) or frozen storage. In the literature, processing techniques such as juicing or drying have negatively affected the content of bioactive chemical compounds. Among drying techniques, hot air (oven) drying is the process that alters the content of bioactive chemical compounds the most. For this reason, new drying technologies such as microwave and heat pumps have been developed. These novel techniques are more successful in retaining bioactive chemical compounds with respect to conventional hot air drying. This mini-review surveys recent literature concerning the effects of postharvest storage and processing techniques on raspberry bioactive chemical compound content.