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Nonthermal processing can change and improve the composition of food. This study examines the impact of cold plasma technology—glow discharge, dielectric barrier discharge (DBD), and ultrasound (US)—on the bioaccessibility of ascorbic acid (vitamin C) and total phenolic compounds (TPCs) in orange and cashew apple juice after simulated digestion. The juices were treated by DBD plasma for 20 min at three different frequencies (50, 500, and 1000 Hz), glow discharge plasma at three synthetic air flow rates (10, 20, and 30 mL/min), and US at three potencies (183, 280 and 373 W/cm2) for 10 min. The nonthermal processing did not significantly reduce the levels of ascorbic acid in cashew apple juice. In contrast, the ascorbic acid levels either remained stable or increased by up to 80% for orange juice. The processing improved the bioaccessibility of total phenolic compounds (TPCs) in both juices, reaching 150% in cashew apple juice treated with US at 373 W/cm2. Despite the decrease in the bioaccessibility of ascorbic acid in orange juice, the nonthermal processing notably enhanced this bioactive compound's bioaccessibility by 10% to 20% compared to the control sample, highlighting the potential of nonthermal technologies to improve the nutritional quality of foods. [ABSTRACT FROM AUTHOR]

Nuclear magnetic resonance (NMR) is a powerful technique to characterization of taste profile based on organic compounds from foods. Likely, gas chromatography coupled to mass spectrometry (GC-MS) enables the detection of aroma profile of foodstuff. Therefore, the present study aimed to evaluate the influence of two different cold plasma processes (dielectric barrier discharge atmospheric plasma (ACP) and glow discharge plasma (GP)), as well as the effect of different processing conditions on taste and aroma profiles from camu-camu juice. Both ACP and GP processing resulted in modifications on taste and aroma, which were strongly dependent of the frequency of plasma generation, flow rate, and treatment duration. The GP processing resulted in higher influence on camu-camu composition than ACP, which decreased the contents of important flavor compounds while increasing vitamin C and ethanol contents. Moreover, GP during 10 min at 10 mL/min and 20 min at 20 mL/min of plasma flow rate did not present significant effect on the juices composition as a whole (taste and aroma related compounds). The ACP processing presented significant influence on the juices composition at 420 and 530 Hz, while 200 and 960 Hz maintained the overall organic composition. Therefore, the use of NMR and GC-MS coupled to advanced chemometric analysis (data fusion) allowed a deep understand the camu-camu chemical variability submitted to plasma technologies based on taste and aroma compounds. This information indicates that appropriate treatment conditions are important for decontamination while preserving and improving the food characteristics in order to match the consumer demands. [ABSTRACT FROM AUTHOR]

BACKGROUND A viable possibility for the best use of bioactive compounds present in camu‐camu, fruit native to the Amazonian rainforest, is the preparation of microcapsules using different biopolymers by the spray‐drying technique, which would increase the possibilities for innovation in the food industry, as well as facilitate the application in different food matrices. In this context, the chemical, physicochemical, and morphological properties and stability of camu‐camu extract (peel and pulp) spray‐dried using maltodextrin, inulin, and oligofructose as encapsulating agents were investigated, as well as lyophilized camu‐camu extract (CEL). Different relative humidities (22%, 51%, and 75%) and temperatures (25 °C and 45 °C) were evaluated. RESULTS: The moisture, water activity, and solubility values varied from 18.4 to 107.9 g water per kilogram dry powder, 0.06 to 0.27, and 950.80 to 920.28 g microparticles per kilogram of water respectively. Retention of the bioactive compounds varied in the ranges 5.5–7.1 g per kilogram ascorbic acid fresh weight and 7.2–9.0 g per kilogram anthocyanins fresh weight. The increase in temperature and relative humidity during storage provided a significant decrease in the stability of the bioactive compounds for all treatments. However, the CEL presented higher water adsorption kinetics and degradation under all storage conditions, indicating the importance of the use of encapsulating agents. CONCLUSION: In general, the prebiotic biopolymers used as encapsulating agents in the microencapsulation of extracts of camu‐camu by spray‐drying presented satisfactory results, suggesting that this technique is an effective strategy to increase the stability of bioactive compounds contained in fruits and vegetables. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

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 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]

• Camu-camu extract was subjected to microencapsulation with prebiotic biopolymers. • High volatiles retention was observed in the camu-camu extract microparticles. • Korsmeyer-Peppas model described the controlled release of bioactive compounds. • Controlled release occurred through Fickian diffusion mechanism. • Encapsulating materials were effective in production of camu-camu extract powder. Camu-camu (Myrciaria dubia [H.B.K] McVaugh) is a Amazonian fruit rich in ascorbic acid and phenolic compounds, and has been attracting great interest from the food, pharmaceutical and nutraceutical industries due to its potential health benefits. The bioactive compounds from camu-camu are considered sensitive and unstable, resulting in nutritional losses and impairment of its commercialization and export. For this reason, the camu-camu extract (pulp and peel) was subjected to microencapsulation by spray drying process using maltodextrin (MD), inulin (IN), and oligofructose (OL) as carrier agents. Lyophilized in natura camu-camu extract (CEL) was also evaluated. Thus, physicochemical and thermal properties and controlled release at different temperatures (25 °C and 35 °C) were investigated. In contrast with the IN and OL microparticles, the MD microparticles showed lower density and hygroscopicity, besides greater thermal stability, antioxidant activity, and retention of ascorbic acid and anthocyanins. FTIR spectra allowed the qualitative evidence of encapsulation of the bioactive compounds from the camu-camu extract. The highest percentage of volatile compounds was observed in IN microparticles, followed by OL and MD microparticles. The major group of compounds identified in CEL were terpenes (88%). The Korsmeyer-Peppas mathematical model allowed to describe the controlled release behavior of ascorbic acid and anthocyanins in the powder extracts. The controlled release followed a Fickian diffusion mechanism (n ≤ 0.43). The increase of temperature from 25 °C to 35 °C influenced on the release of bioactive compounds in all treatments, showing greater release for MD microparticles. The encapsulating materials were considered effective for the production of camu-camu extract powder, contributing to the better use of this Amazonian fruit. In addition, the encapsulation process increased the stability of its bioactive compounds, representing a tool to facilitate their incorporation in several matrices to act as antioxidant and coloring agents, as well as nutraceutical. [ABSTRACT FROM AUTHOR]

Camu-camu is a red berry rich in bioactive compounds such as ascorbic acid and anthocyanins. In this study, the main objective was to evaluate the effect of thermosonication on the physicochemical changes of camu-camu nectars, alterations such as those in quality parameters (pH, titratable acidity, soluble solids and cloud value), vitamin C, antioxidant activity, anthocyanin content, phenolic compounds, enzymes (PPO and POD) color parameters (L*, a*, b* and ΔE*) and microbiological quality. The thermosonication improved the bioavailability of the bioactive compounds, increased the cloud value and maintained the physicochemical properties of the camu-camu nectars. The enzymatic activity was reduced with increasing time and temperature processing. No microorganisms were observed after thermosonication processing. This study shows that thermosonication could be employed as a preservation technique for fruit nectar processing where bioactive compounds retention is desired. [ABSTRACT FROM AUTHOR]

• Camu-camu juice was processed using cold plasma. • Different levels of excitation frequency were evaluated. • Increasing the excitation frequency of cold plasma influenced the ascorbic acid content. • Cold plasma denatured peroxidase and polyphenol oxidase. • Cold plasma increased vitamin C bioavailability. The aim of this paper was to evaluate the effect of cold plasma excitation frequency on camu-camu juice processing. Different levels of frequency (200, 420, 583, 698 and 960 Hz) were applied on camu-camu juice to measure the contents of ascorbic acid and anthocyanins, as well as to evaluate the antioxidant compounds (DPPH, ABTS, FRAP and phenolic compounds), peroxidase and polyphenol oxidase enzymatic activity and color. Furthermore, the juice bioaccessibility was evaluated after simulated digestion. The ascorbic acid concentration was increased when higher excitation frequencies were employed, increasing their bioavailability. Anthocyanins, peroxidase and polyphenol oxidase presented considerable degradation with increasing the plasma excitation frequency. For this reason, the juice processing proposed herein represents an alternative to enhance its nutritional quality. Moreover, the use of cold plasma reduced the activity concentration of endogenous enzymes, presenting considerable degradation for higher excitation frequency. [ABSTRACT FROM AUTHOR]