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An experimental study was conducted to assess the drying kinetics of lemongrass shreds, dried using two different drying methods and retention of bioactive compounds in the dried lemongrass. Convective drying (CD) was carried out at 45°C for 7 h, whereas during pulsed microwave drying (PMD), lemongrass shreds were exposed to microwaves at 1350 W for 3‐3‐2‐1‐min pulsed intervals with a 30‐s pulse gap. Experimental data were fitted to three drying models, namely Lewis, Henderson and Pabis, and Page models, to determine the moisture ratio as a function of drying time. The bioactive compounds were analyzed before and after drying to assess the changes during the drying process. Pulsed microwave dried samples showed maximum retention of total chlorophyll: 13.85 mg/g, ascorbic acid: 17.80 mg/100 g, flavonoids: 2.64 mg/g, and highest antioxidant capacity of 74.02%. Moreover, microwave‐assisted hydrodistillation (MAHD) of these samples yielded 1.54% essential oil with a specific gravity of 0.89. Novelty impact statement: The synergistic influence of PMD and MAHD process on the quality of dried lemongrass shreds has not been investigated earlier.Polynomial fit‐MR and polynomial fit‐lnMR for moisture ratio were found to have the highest R2 values for both drying methods.Retention of bioactive compounds was observed to be higher in PM dried samples compared with convective dried samples. [ABSTRACT FROM AUTHOR]

As an agro‐food by‐product, pomegranate peel is a potential source of bioactive compounds with preservative properties. Ultrasound‐assisted extraction (UAE) is a green extraction method that is useful in increasing extraction yields and reducing extraction time without using toxic solvents. This study aimed to optimize the UAE of a pomegranate peel for its use as a preservative using water as the solvent, maximizing its antioxidant potential for its particular application to chicken burgers. A Box–Behnken design was applied using extraction time, extraction temperature, and ultrasound amplitude as independent variables. The response surface methodology (RSM) results showed that the highest concentration of the phenolic compound is obtained at amplitude—50%, temperature—38°C, and time—15 min. The extracts with RSM conditions at a concentration of 0.8% indicated that the extracted preservative exerts the ability to delay meat oxidation on days 1, 2, 4, and 7, even better than ascorbic acid. Practical applications: The waste and elimination of agro‐industrial by‐products generate significant environmental impacts and critical economic losses. Today, a sustainable paradigm it seeks to add extra value to these by‐products by giving them a new application in the production chains, thus favoring the circular economy. The ultrasound‐assisted process is an excellent tool to obtain green compounds that cover the recent concern from the industry and consumers for healthier foods. In this case, the application of the pomegranate peel extract is presented as an alternative to synthetic preservatives due to its great antioxidant capacity. [ABSTRACT FROM AUTHOR]

Application of weak acid and preservatives on tomatoes has the potential to reduce the loss of functional properties during drying. The effects of using sodium metabisulphite (SMB) and citric acid (CA) to control the degradation of nutraceuticals in dried tomatoes were studied. The following treatments: T0 (control, no additives), T1 (1% w/v CA), T2 (0.5% w/v CA +0.5% w/v SMB), and drying methods (dehydration, sun, and solar) were used. The T2 pretreated samples, dried using the sun, solar, and dehydration had total soluble solids (TSS) (5.10%), total sugar (TS) (7.32 g/100 g), and rehydration ratio (RR) (2.0) and β‐carotene (30.0 mg/100 g), lycopene (51.3 mg/100 g), ascorbic acid (14.1 mg/100 g), respectively. The T2 pretreated and dehydrated samples had a high Trolox equivalent antioxidant capacity (TEAC) and 2,2‐diphenyl‐1‐picrylhydrazyl radical scavenging activity. By using T2 treatment and dehydration, the tomato had the best functional properties, which would be used as optimal conditions for preserving tomatoes. Novelty impact statement: Hybrid Amukela Plus tomatoes pretreated with 0.5% w/v CA +0.5% w/v SMB and dried ‐in a food dehydrator preserved ‐further degradation of nutraceutical compounds and resulted in a β‐carotene (30.0 mg/100 g), lycopene (51.3 mg/100 g), and ascorbic acid (14.1 mg/100 g) content during storage. These treatments produced dried tomatoes with over 50% Trolox equivalent antioxidant capacity (TEAC) and 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical scavenging activity. Solar and sun‐drying treatments have significant damage on the nutraceutical compounds in the dried hybrid tomatoes. [ABSTRACT FROM AUTHOR]

Effect of vacuum impregnation (VI) times on quality and healthy potential attributes of fresh‐cut apples was modeled, determining optimal processing times. Mild VI treatments (67.7 mbar vacuum pressure, 30 oBrix sucrose osmotic solution containing citric and ascorbic acids) were applied with vacuum (tv) and relaxation (tr) times of 1.14 to 14 min through a central composite design. After VI, respiration rate decreased as tv increased but increased with tr. Bioactive compounds and antioxidant capacity increased with both processing times. Optimal tv and tr obtained for minimizing respiration rate and maximizing the attributes related to sensory quality were 6.18 and 1.14 min. Otherwise, optimal tv and tr for minimizing the respiration rate, maximizing the related sensory properties, and the health potential of fresh‐cut apples were longer (10.18 and 6.21 min). Mild VI, with an antioxidant solution at appropriate VI times, is an adequate technology for obtaining fresh‐cut apples with improved fresh‐like quality and healthy characteristics. Novelty impact statement: This study showed that mild vacuum impregnation treatment with an antioxidant solution is an adequate technology for processing fresh‐cut apples with improved healthy potential. The optimal vacuum and relaxation times improve the fresh‐cut apple qualities and its health potential after 7 days of storage at 1.5°C if both are suitably selected. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effect of high hydrostatic pressure (HHP) (250 or 400 MPa/5 min) and storage conditions (2 or 27℃/24 hr) on polyphenols, ascorbic acid, antioxidant capacity, polyphenol oxidase (PPO), and color in fresh‐cut cashew apple. The association of HHP and storage decreased ascorbic acid (14%–49%), soluble polyphenols (13%–43%), and antioxidant capacity (41%) and modified phenolic acids profile. Protocatechuic acid was detected in samples after cut and storage. The association of HHP and storage at 27℃ led to hydrolysis of conjugated cinnamic acid, but did not change the flavonoids profile. PPO activity was enhanced after treatment of 250 MPa. Storage at room temperature changed all color parameters and HHP treatment promoted great color differences. Processing at 400 MPa followed by storage at 2℃ seems to be more suitable to fresh‐cut cashew apple since it was less detrimental to ascorbic acid, phenolics, and antioxidant capacity. Practical applications: Cashew apple is a fruit, which is rich in bioactive compounds, ascorbic acid, and polyphenol oxidase, but despite its nutritional content it undergoes fast deterioration, so that HHP could be an alternative to increase its shelf life and consumption. Treatment at 400 MPa and low storage temperature retains ascorbic acid, phenolic compounds, and antioxidant capacity of fresh‐cut cashew apples. The outcomes could help the food industry apply HHP associated with adequate storage temperature to the cashew apple food products to meet the quality standards. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the combined effects of ultrasound (US) and pulsed electric field (PEF) treatment on spinach juice. The spinach juice was sonicated at a frequency of 40 kHz, radiating power 200 W, and temperature 30°C for 21 min in an ultrasonic bath, followed by PEF treatment (pulse frequency: 1 kHz, flow rate: 60 ml/min, temperature: 30°C, time: 335 µs, and electric field strength 9 kV/cm). The combined treatment (US‐PEF) has achieved the highest value of flavonoids, phenolic, flavonols, anthocyanin, carotenoids, total chlorophyll, vitamin C, DPPH, and total antioxidant capacity than single treatments of US and PEF as well as untreated sample. The inactivation of peroxidase and polyphenol oxidase was increased during US‐PEF treatment from 0.85 and 0.025 Abs/min (untreated) to 0.18 and 0.011 Abs/min, respectively. There was a slightly visible variation in color values among all the treatments. Practical applications: Nowadays, novel processing techniques, are employed to improve the nutritional quality and stability of juices. The consequences of the present research showed that combined treatment (US‐PEF) could improve the TPC, TFC, total flavonols, antioxidant activities, chlorophyll, carotenoids, vitamin C, and anthocyanins content while reducing the activity of the enzyme. The verdicts described that US‐PEF can enhance the quality of spinach juice at an industrial scale. [ABSTRACT FROM AUTHOR]

Grapefruit (Citrus × paradisi, Algerian variety) essential oil obtained by hydro‐distillation was evaluated as a substitute for vitamin E for margarine. The obtained IC50 values were: 39.92 ± 0.18, 15.09 ± 0.02, and 4.42 ± 0.03 mg/ml by the 2,2‐diphenyl‐1‐picrylhydrazyl method, the reducing power and the β‐carotene/linoleic acid tests, respectively. These results were higher compared to those of the synthetic antioxidants. Values for BHA in DPPH and β‐carotene/linoleic acid assays were 0.158 ± 0.003 and 0.032 ± 0.000 mg/ml, respectively. The result of ascorbic acid for reducing power was 0.053 ± 0.001 mg/ml. Analysis of composition showed 128 volatile compounds. The limonene was the major compound (67.22%) followed by trans‐citral (5.39%) and isoauraptene (2.85%). All samples were fortified with 12.5, 50 and 100 µg/g of essential oil. The Rancimat test demonstrated that the lowest concentration of essential oil gave the best resistance to oxidation (22.6 hr). Novelty impact statement: Grapefruit essential oil was used as a substitute for vitamin E for margarine, and it gave better resistance to oxidation than control samples. The presented solution could be successfully applied on an industrial scale. [ABSTRACT FROM AUTHOR]

Influence of particle size distribution on nutritional composition, microstructural, physicochemical, and antioxidant properties of orange and purple‐fleshed sweet potato flour (SPF) with particle sizes 75–355 µm were investigated. As particle size decreased, protein content, water absorption capacity, and water solubility index of both SPF decreased, whereas starch, reducing sugar, and crude fat increased. Total polyphenol contents (TPC) in purple‐fleshed SPF (8.25–9.27 mg GAE/g DW) were higher than orange ones (0.22–0.28 mg GAE/g DW), whereas vitamin C contents in orange‐fleshed SPF (23.59–29.26 mg/100 g DW) were higher than purple ones (4.24–4.89 mg/100 g DW). Antioxidant capacities of both SPF were gradually increased with decrease of particle size due to the contribution of higher TPC and vitamin C contents. All SPF fractions exhibited irregular‐shaped surface. SPF with particle size 75 µm might be used to produce novel food products with desired nutrients and functional properties. Novelty Impact Statement: Both orange and purple‐fleshed SPF with different particle sizes possessed significant difference in nutritional composition and antioxidant properties. TPC contents in purple‐fleshed SPF were higher than orange ones, whereas vitamin C contents in orange‐fleshed SPF were higher than purple ones. SPF with particle size 75 µm with higher polyphenols and vitamin C contents and stronger antioxidant activities might be used to produce novel food products. [ABSTRACT FROM AUTHOR]

This research focused on 1‐methylcyclopropene (1‐MCP) effect during carbon dioxide atmosphere storage on physiology and quality of fresh‐cut Fuji apples. Firmness, color, ascorbic acid, titratable acidity, malondialdehyde (MDA), lipoxygenase (LOX), peroxidase (POD), superoxide dismutase (SOD), polyphenol oxidase (PPO), and catalase (CAT) activities of fresh‐cut Fuji apples were examined. And it turns out under the condition of carbon dioxide storage, 1‐MCP treatment could speed up the decrease of firmness, titratable acidity, and ascorbic acid. Moreover, it enhanced the browning and MDA content of the fruit. Therefore, our results suggested that 1‐MCP + CO2 treatment could enhance carbon dioxide injury as compared with CO2 treatment alone. Furthermore, 1‐MCP + CO2 treatment maintained higher SOD, CAT, POD, PPO, and LOX activities. Overall, 1‐MCP + CO2 treatment enhanced carbon dioxide injury during the storage of high concentration carbon dioxide, possibly through the regulation of LOX activity. Practical applications: The combination of 1‐MCP and CO2 may need to be avoided in fresh‐cut Fuji apple preservation. Moreover, 1‐MCP + CO2 increased antioxidant capacity, including SOD, CAT, PPO, and POD activities, which may provide suggestions for a breakthrough for new preservation methods. [ABSTRACT FROM AUTHOR]

Petit‐Suisse goat cheese with multifunctional properties associated with acerola pulp and a potentially probiotic autochthonous strain of Lactobacillus plantarum were developed. The effect of incorporating acerola pulp into the cheese on the viability and survival of Lb. plantarum to in vitro gastrointestinal conditions, antioxidant capacity, and sensory features were studied. The freeze‐dried culture of Lb. plantarum exhibited high viability (8.34 log CFU/g), which remained above 8 log CFU/g in the cheeses. Acerola pulp incorporation did not affect in vitro survival of the probiotic (73% at 14 days), and enriched the Petit‐Suisse cheese with antioxidant compounds, increasing concentrations of ascorbic acid, and polyphenols (up to 132.73 mg.100/g and 255.08 mg.100/g, respectively), and EC50 values of DPPH● and ABTS●+ (up to 6,331.74 g/g DPPH● and 7.91 µM Trolox/g, respectively). The cheese showed high sensory acceptance. Practical applications: Petit‐Suisse cheese flavored added by acerola pulp is promising as a multifuncional food product. The use of acerola pulp is an interesting option, as the fruit is well accepted and Brazil is one of the largest producers in the world. In this study, acerola pulp (10%) and potentially probiotic Lb. plantarum CNPC003 were used to develop Petit‐Suisse goat cheese. The effect of acerola pulp on physicochemical, probiotic, and antioxidant properties were evaluated. Acerola pulp can provide remarkable antioxidant activity without affecting the viability and in vitro survival of the potentially probiotic strain, indicating that the developed cheese may have dual function of antioxidant and probiotic potential, thus making it more attractive to consumers. [ABSTRACT FROM AUTHOR]

The effects of hot air drying (HD), freeze‐drying (FD), microwave drying (MWD), natural convective drying (NCD), and vacuum drying (VD) on the physicochemical, nutritional, and antioxidant properties of okra pods were investigated. Changes in the surface morphology, color, rehydration ratio, protein, pectin, ascorbic acid, and phenolics, as well as antioxidant activities of okra pods measured by 2,2′‐azinobis (3‐ethylbenzo thiazoline‐6‐sulphonic acid) diammonium salt (ABTS), 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH), and Ferric Ion Reducing Antioxidant Power (FRAP) assays were evaluated. In general, FD products exhibited a better retention of the texture characteristics, nutritional, and antioxidant activities, and was suitable for okra pods drying, although FD was the longer time‐consuming method among the five drying methods. Furthermore, NCD products were poorer in color, texture, and nutrition. Future studies should continuously focus on various combinations of different types of drying methods to supply okra pods products with the most affordable cost and the highest quality. Practical applications: Physicochemical properties and antioxidant capacities of okra pods are affected by the drying process. The drying process with nonthermal, low temperature, and low content of oxygen is beneficial to the retention of nutrients and functional components. In general, freeze‐drying exhibited a better texture characteristics and good antioxidant activities, although higher energy and longer time consumption was the current challenge. How to combine the different types of drying methods has become an inevitable trend and research focus. [ABSTRACT FROM AUTHOR]