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The effects of processing time (10, 20 and 30 min) and plasma flow rate (10, 20 and 30 mL min−1 of synthetic air) on the bioactive compounds of camu-camu juice (Myrciaria dubia) treated using glow plasma were evaluated herein. Plasma technology promoted the increase of the bioactive compounds' concentration (antioxidant compounds, ascorbic acid and total monomeric anthocyanins) in the juice serum. Peroxidase and polyphenol oxidase presented the higher reduction of the enzymatic activity for treatments using plasma flow rate of 20 mL min−1. The treatments with higher air flow rate presented great color change (ΔE* > 2). Furthermore, the bioavailability of ascorbic acid was increased after using plasma technology. Therefore, the cold plasma technology may represent a useful technique to improve the bioavailability of bioactive compounds in processed fruit juices. [ABSTRACT FROM AUTHOR]

The influence of ultrasound (US)‐assisted homogenization and gum Arabic (GA) on the colloidal stability of cupuaçu juice has been studied. The experimental design was a complete factorial with two levels for US (750 and 1,000 J/cm3) and GA (0.5 and 1% w/w). The increase in energy density and GA concentration increased the viscosity of the juice, reducing its sedimentation. Increased energy density occurs to increased bioavailability of vitamin C in cupuaçu juice serum. The two levels of energy density of US were effective in the denaturation of the polyphenol oxidase and peroxidase enzymes. The use of US and GA may be a good alternative for the food industry to maintain the physicochemical properties of cupuaçu juice during storage. Practical applications: Cupuaçu is a fruit with great economic importance for the region of the Amazon Rainforest. Due to their physical characteristics, the juices present a rapid phase separation and it can compromise their processing and sensorial acceptance. The use of the ultrasonic homogenization process and the addition of natural hydrocolloids (GA) can improve the physical juice quality because the US reduces the particles size and the hydrocolloid increases the viscosity of the serum, reducing the separation of the phases of the juice. Also, the study is interesting due to the use of nonthermal technologies and natural additives, maintaining the nutritional juices quality. [ABSTRACT FROM AUTHOR]

The objective of this work was to evaluate microwave heating (MW) in the processing of camu‐camu juices. A factorial design (22) with repetition at the central point was performed. We evaluated the effect of microwave power (310‐940 W) and processing time (15‐45 s) on physicochemical characteristics, reduction of enzyme activity (POD and PPO), microbiological quality and bioactive compounds content (DPPH, phenolic compound, ascorbic acid, and anthocyanins). Generally, the juices treated by MW presented better results in comparison to the conventional method. There were no significant changes in pH, titratable acidity, total soluble solids, and color parameter in camu‐camu juices in comparison with untreated samples. The ascorbic acid content in the juices increased after the treatment by MW. A significant reduction of degrading microorganisms was observed for the treated juice in relation to the control juice. Microwave heating can be a good alternative for the treatment of Amazonian fruit juices. Practical applications: The global consumer market requires that foods be high in bioactive compounds to improve human health. The Amazon Rainforest is known worldwide for its rich biodiversity, mainly for its wide variety of foods rich in bioactive compounds. The lack of transportation infrastructure and basic sanitation in the region causes the food to present high microbial contamination that can accelerate food degradation, especially its bioactive compounds. The use of microwave heating may be an opportunity to offer a fast, efficient, and low‐cost process for the reduction of microorganisms in fruit juices and pulps. This study is a pioneer in the use of emerging technologies in the conservation of Amazonian fruit juices, allowing a new opportunity for the food industry to offer products with high nutritional value. [ABSTRACT FROM AUTHOR]