Effects of short-wave ultraviolet light, ultrasonic and microwave treatments on banana puree during refrigerated storage

Abstract

Enzymatic browning is a major problem in minimally processed banana puree; it reduces consumeŕs acceptability and affects nutritional quality. The objective of this work was to evaluate the effects ultrasound (40 kHz/10 min), microwave (800 W/ 25 s) and UV-C radiation (1.97 kJ/m2) applied to banana puree. Colour parameters (L*, a*, b*, chroma and hue), browning index (BI), polyphenol oxidase (PPO) and peroxidase (POD) activities, total phenolic compounds (TPC), antioxidant capacity (AOC) and microbiological counts were monitored throughout storage at 4°C. Ultrasound (US) and microwave (MW) treatments achieved a significant (p < 0.05) reduction in PPO activity and BI; moreover, ultrasound effectively retained phenolic compounds content (75% of initial value). The AOC was in coincidence with TPC values. POD activity was partially inhibited by UV-C while MW and US increase its activity. Although UV-C treatment was not effective to control browning development, it was effective to maintain microbiological stability after 20 days of storage (1.48 ± 0.01 log CFU/g). The evaluated treatments have the advantage of being less aggressive than conventional thermal treatments while maintaining fresh characteristics of the product.

The Stability of Phenolic Compounds in Fruit, Berry, and Vegetable Purees Based on Accelerated Shelf-Life Testing Methodology

“…In addition, as consumers are becoming more aware of sustainable packaging, industries must provide it to keep up with the demand, ensuring there is no loss in product quality and storage time [27]. However, as the purees need barriers against light and gases to maintain their quality during storage [28,29], packages including aluminum are still often used. Aluminum provides excellent barriers and, at the same time, is stable over a wide range of temperatures, not generating toxic releases when exposed to food.…”