Effect of microwaves and ultrasound on bioactive compounds and microbiological quality of blackberry juice

Microwave Treatment vs. Conventional Pasteurization: The Effect on Phytochemical and Microbiological Quality for Citrus-Maqui Beverages

This study uncovered the impacts of microwave (MW) treatments compared to conventional pasteurization (TP) on the quality of functional citrus-maqui beverages, with added sucrose or stevia. The influence of these thermal treatments on the microbiological burden and phytochemical composition was determined by processing under two MW power levels (600 W and 800 W) and TP at 85 °C for 15 s for 60 days at room temperature (20 °C). The results indicated that, beyond the microbiological quality achieved in the juices treated by both MW and TP technology, there were no differences among the treatments regarding the stability of vitamin C, anthocyanin, and flavanone concentrations. However, anthocyanins were more stable in those beverages with sucrose added, rendering a better red color. Besides, all treatments ensured microbiological stability throughout the entire storage time. In conclusion, MW treatment could be considered as an alternative to TP, which ensures microbial safety, protecting functional compounds associated with health effects.

Trends in maintaining postharvest freshness and quality of Rubus berries

Blackberries and raspberries, commonly known as Rubus berries, are commercially grown worldwide across different climates. Rubus berries contain wide array of phytochemicals, vitamins, dietary fibers, minerals, and unsaturated fatty acids. Nevertheless, these berries have short storage life which is the major constraint in their supply chains leading to higher postharvest losses. Inappropriate harvest handling, physical bruising, insect pests, and postharvest diseases lower the acceptability of fruit among consumers and other supply chain stakeholders. Additionally, the susceptibility to microbial decay, fruit softening, higher ethylene production, respiratory activity, and increased oxidation of anthocyanins, phenolics, and flavonoids considerably affects the marketability of Rubus berries at domestic and international markets. To date, several postharvest strategies such as cold storage, precooling, modified and controlled atmospheres, anti-ripening chemicals, edible coatings, biological agents, and nonchemical alternatives (heat treatment, ultrasound, irradiations, ozone) have been reported to prolong storage life, ensure food safety, and maintain the nutritional quality of Rubus berries. This review briefly encompasses multiple aspects including harvest maturity indices, regulation of fruit ripening, pre and postharvest factors affecting fruit quality, and an update on postharvest quality preservation by employing postharvest technologies to extend the storage life and maintaining the bioactive compounds in Rubus berries which are lacking in the literature. Accordingly, this review provides valuable information to the industry stakeholders and scientists offering relevant solutions, limitations in the application of certain technologies at commercial scale, highlighting research gaps, and paving the way forward for future investigations.

Effect of Blackberry Juice Consumption by Pregnant Rats on Brain Length and Cell Density of Dentate Gyrus in Male Wistar Pups

The aim of this work was to evaluate the effect of blackberry juice consumption during pregnancy on the length of the brain, as well as on the cell density of the dentate gyrus in Wistar rat pups. Pregnant rats were divided into three groups: control (C), fed with standard diet and water ad libitum; BJ1, which received blackberry juice containing polyphenols (7.8 mg/kg) and anthocyanins (1.9 mg/kg); and BJ2, receiving blackberry juice containing polyphenols (9.3 mg/kg) and anthocyanins (3.54 mg/kg). On postnatal day 0, pups per litter, body weight, and length were measured, and cells in the dentate gyrus of male pups were quantified. Maternal body weight and pups per litter were statistically equal across experimental groups during pregnancy. Pups in BJ1 and BJ2 groups showed an increase in body weight (20%) and length (5%) when comparing to controls. An increase in brain length was observed in BJ2 group (8%) as compared to the control. A significant increase in the number of cells/mm2 was observed in the dentate gyrus of the offspring in BJ1 (21.8%) and BJ2 (23.7%) groups when compared to the control group. Given the above, blackberry juice may be considered a potential functional food during pregnancy, while further research on prenatal and postnatal development must be done.

Research progress and application of ultrasonic- and microwave-assisted food processing technology

Microwaves are electromagnetic waves of specific frequencies (300 MHz-3000 GHz), whereas ultrasonic is mechanical waves of specific frequencies. Microwave and ultrasonic technology as a new processing method has been widely used in food processing fields. Combined ultrasonic and microwave technology is exploited by researchers as an improvement technique and has been successfully applied in food processing such as thawing, drying, frying, extraction, and sterilization. This paper overviews the principle and characteristics of ultrasonic- and microwave-assisted food processing techniques, particularly their combinations, design of equipment, and their applications in the processing of agricultural products such as thawing, drying, frying, extraction, and sterilization. The combination of ultrasonic and microwave is applied in food processing, where microwave enhances the heating rate, and ultrasonic improves the efficiency of heat and mass transfer. The synergy of the heating effect of microwave and the cavitation effect of ultrasonic improves processing efficiency and damages the cell structure of the material. The degradation of nutrient composition and energy consumption due to the short processing time of combined ultrasonic and microwave technology is decreased. Ultrasonic technology, as an auxiliary means of efficient microwave heating, is pollution-free, highly efficient, and has a wide range of applications in food processing.

Solvent-free sonication of blackberries for the anthocyanin enrichment of juices obtained by pressing

An ultrasound pretreatment was used to increase anthocyanins content in blackberry juice. Whole fruits were inserted into a glass vessel without contact with any solvent, sonicated in an ultrasonic bath, and then pressed with a manual juicer. The experimental design showed that 7 min at 65% of ultrasound amplitude increased the anthocyanin content in juices from 31 to 56% for BRS Xingu, Guarani, and Xavante cultivars. Two major anthocyanins, cyanidin-3-glucoside and cyanidin-3-rutinoside were found in higher concentrations for sonicated fruits. Therefore, ultrasonic pretreatment of whole fruits increased the anthocyanins in blackberry juices using a simple, fast, and green approach.

Effects of Processing Conditions and Simulated Digestion In Vitro on the Antioxidant Activity, Inhibition of Xanthine Oxidase and Bioaccessibility of Epicatechin Gallate

The bioactivity and gastrointestinal stability of epicatechin gallate (ECG) may be affected by processing conditions. Results showed that the antioxidant ability and inhibitory activity on xanthine oxidase (XO) of ECG were higher at low pH values. Appropriate microwave and heating treatments improved the antioxidant (the scavenging rate increased from 71.75% to 92.71% and 80.88% under the microwave and heating treatments) and XO inhibitory activity (the inhibitory rate increased from 47.11% to 56.89% and 51.85% at the microwave and heating treatments) of ECG. The treated ECG led to a more compact structure of XO. Moreover, there may be synergistic antioxidant and inhibitory effects between ECG and its degradation products. The bioaccessibility of ECG after simulated digestion was untreated > microwave > heating, and the microwave-treated ECG still had good XO inhibitory activity after digestion. These findings may provide some significant information for the development of functional foods enriched in catechins.

Effect of anthocyanin-rich blackberry juice on endoplasmic reticulum stress in streptozotocin-induced diabetic rats

This study investigates blackberry juice's effects on glucose metabolism, oxidative stress, inflammation, and endoplasmic reticulum stress (ER) in streptozotocin (STZ)-induced diabetic rats. Fifty Wistar rats were distributed to five groups randomly of ten rats each: Normal control, diabetic control, 9 mL/kg body weight (b.wt) blackberry juice only, blackberry juice plus diabetes, and 500 mg/kg b.wt metformin plus diabetes. A single intraperitoneal injection of 50 mg/kg b.wt STZ induced diabetes in the rats. This animal study continued for 56 days after the confirmation of diabetes. The levels of liver function and renal function, as well as insulin, glucose-6-phosphatase, glucokinase, and malondialdehyde (MDA) levels, and the activities of catalase (CAT) and superoxide dismutase (SOD), were determined. Additionally, interleukin-6 (IL-6) levels, tumor necrosis factor-alpha (TNF-α), and activated transcription factor 4 (ATF4) expressions were examined in the liver homogenate of rats. Furthermore, the liver tissues were utilized for histopathological examination. The results showed that blackberry juice prevented drastic loss of body weight and reduced food consumption in diabetic rats. Additionally, the levels of blood glucose, total protein, aspartate aminotransferase (AST), albumin, alanine aminotransferase (ALT), uric acid, creatinine, and urea improved after the administration of blackberry juice in diabetic rats. Blackberry juice significantly increased glucose metabolism and antioxidant status while reducing ER stress and inflammation in diabetic rats. Moreover, blackberry juice improved glucose metabolism by increasing insulin levels and improving the dysregulated activities of glucose-metabolizing enzymes. The microstructure of liver tissues in diabetic rats was also improved with blackberry juice treatment. Therefore, blackberry juice has the potential to alleviate diabetes in rats and could be considered as a functional food for people with diabetes.

Food processing to reduce antinutrients in plant-based foods

Antinutrients such as phytic acids, tannins, saponin, and enzyme inhibitors are phytochemicals that can decrease the bioavailability of micro- and macronutrients, thus causing them to be unavailable for absorptions in the digestive system. Antinutrients are a major concern especially in countries where plant-based commodities such as wheat, legumes, and cereals are staple foods, for the antinutrients can cause not only mineral deficiencies, but also lead to more serious health issues. Although various thermal and non-thermal processing methods such as cooking, boiling, and fermentation processes have been practiced to decrease the level of antinutrients, these processes may also undesirably influence the final products. More advanced practices, such as ozonation and cold plasma processing (CPP), have been applied to decrease the antinutrients without majorly affecting the physicochemical and nutritional aspects of the commodities post-processing. This review will cover the types of antinutrients that are commonly found in plants, and the available processing methods that can be used, either singly or in combination, to significantly decrease the antinutrients, thus rendering the foods safe for consumption.

Sensory evaluation of microwave-ultrasound treated bottle gourd juice using hybrid features of fuzzy logic and proportional odd modelling approach

In the present investigation, sensory evaluation of bottle gourd juice (BGJ) samples, obtained from microwave-ultrasound based combined treatment was performed. The raw (sample-1) and conventionally treated (sample-2) alongside microwave-ultrasound treated (sample-3) were considered for the assessment of sensory evaluation. An innovative approach of hybrid fuzzy logic and proportional odd modelling (FL-POM) was implemented for the analysis of the sensory scores. The similarity values for the juice samples and their quality attributes were resolved from the results obtained by fuzzy logic. These values were considered as input for hybridization with the POM approach. The assessed coefficients obtained from the results of POM were considered for the ranking of the samples and quality traits. The ranking of the BGJ samples was observed in the order of sample-1 > sample-3 > sample-2, and their related quality attributes ranked in the order color > taste > aroma > mouth feel. The microwave-ultrasound treated BGJ evinced as the best sample in comparison to the raw one.

Application and potential of multifrequency ultrasound in juice industry: Comprehensive analysis of inactivation and germination of Alicyclobacillus acidoterrestris spores

The majority of acidic fruits are perishable owing to their high-water activity, which promotes microbial activity, thus exhibiting metabolic functions that cause spoilage. Along with sanitary practices, several treatments are used during processing and/or storage to inhibit the development of undesirable bacteria. To overcome the challenges caused by mild heat treatment, juice manufacturers have recently increased their involvement in developing novel non-thermal processing procedures. Ultrasonication alone or in combination with other hurdle technologies may be used to pasteurize processed fruit juices. Multifrequency ultrasound has gained popularity due to the fact that mono-frequency ultrasound has less impact on bacterial inactivation and bioactive compound enhancement of fruit juice. Here, we present and discuss the fundamental information and technological knowledge of how spoilage bacteria, specifically Alicyclobacillus acidoterrestris, assemble resistant spores and inactivate and germinate dormant spores in response to nutrient germinants and physical treatments such as heat and ultrasound. To the authors' knowledge, no prior review of ultrasonic inactivation and germination of A. acidoterrestris in fruit juice exists. Therefore, this article aims to provide a review of previously published research on the inactivation and germination of A. acidoterrestris in fruit juice by ultrasound and heat.

Potential impact of ultrasound, pulsed electric field, high-pressure processing and microfludization against thermal treatments preservation regarding sugarcane juice (Saccharum officinarum)

Sugarcane juice (Saccharum officinarum) is a proven nutritious beverage with high levels of antioxidants, polyphenols, and other beneficial nutrients. It has recently gained consumer interest due to its high nutritional profile and alkaline nature. Still, high polyphenolic and sugar content start the fermentation in juice, resulting in dark coloration. Lately, some novel techniques have been introduced to extend shelf life and improve the nutritional value of sugarcane juice. The introduction of such processing technologies is beneficial over conventional processes and essential for producing chemical-free, high-quality, fresh juices. The synergistic impact of these novel technologies is also advantageous for preserving sugarcane juice. In literature, novel thermal, non-thermal and hurdle technologies have been executed to preserve sugarcane juice. These technologies include high hydrostatic pressure (HHP), ultrasound (US), pulsed electric field (PEF), ultraviolet irradiation (UV), ohmic heating (OH), microwave (MW), microfludization and ozone treatment. This review manifests the impact of novel thermal, non-thermal, and synergistic technologies on sugarcane juice processing and preservation characteristics. Non-thermal techniques have been successfully proved effective and showed better results than novel thermal treatments. Because they reduced microbial load and retained nutritional content, while thermal treatments degraded nutrients and flavor of sugarcane juice. Among non-thermal treatments, HHP is the most efficient technique for the preservation of sugarcane juice while OH is preferable in thermal techniques due to less nutritional loss.

Preparation of anthocyanin-rich mulberry juice by microwave-ultrasonic combined pretreatment

The work aims to study the process of microwave-ultrasonic combined treatment to obtain anthocyanin-rich mulberry juice. A Box-Behnken design was employed to analyze the effects of microwave time and citric acid content on the total phenol content, total anthocyanin content, hue, color intensity, DPPH and ABTS radical scavenging activities. Under the optimum conditions (microwave time of 46 s, citric acid addition of 273 mg/kg), the total phenol content, total anthocyanin content, the DPPH and ABTS radical scavenging activities reached 4.24 mg GAE/mL, 3.29 mg C3G/mL, 4.59 mg TE/mL and 11.90 mg TE/mL, respectively. Subsequently, the mulberry juice was processed with ultrasound of different frequencies. It was found that low-frequency ultrasonic treatment (25 kHz) could significantly reduce the loss of total phenolic and anthocyanin monomers and improve the antioxidant capacity of mulberry juice during storage for five weeks. Overall, mulberry juice with microwave-ultrasonic pretreatment is a natural antioxidant.

On the Effect of Microwave Heating on Quality Characteristics and Functional Properties of Persimmon Juice and Its Residue

In this study, it was investigated whether integration of microwave-heating into the pretreatment step of persimmon juice processing allows the concomitant production of both functional juice and added-value solid residue from the Diospyros Kaki "Jiro" cultivar. In this direction, persimmon pulp was treated under three different microwave-heating conditions (0.7, 4.2, and 8.4 kJ/g) prior to enzymatic maceration and compared to the non-heated material. Irrespective of microwave energy employed, the proposed hybrid treatment was highly efficient in terms of juice yield (70% w/w). The mildest heating conditions resulted in juice and residue that were both of inferior quality. Intensification of the microwave energy reduced the microbial load of the juice up to 2-log without compromising the content in total soluble solids, sugars, and L-ascorbic acid. Under the most drastic conditions, the juice was enriched in gallic acid, polyphenols, and potent DPPH● scavengers, but its orange color faded and was more acidic. In parallel, the solid juice residue retained pro-vitamin A carotenoids (~278 µg retinol activity equivalents) and low-methoxy pectin (9 g/100 g DW). Overall, our findings can assist the efforts of the local juice processing industry to utilize persimmon fruits through energy-efficient technologies in a sustainable approach.

Strategies to Improve the Potential Functionality of Fruit-Based Fermented Beverages

It is only recently that fermentation has been facing a dynamic revival in the food industry. Fermented fruit-based beverages are among the most ancient products consumed worldwide, while in recent years special research attention has been granted to assess their functionality. This review highlights the functional potential of alcoholic and non-alcoholic fermented fruit beverages in terms of chemical and nutritional profiles that impact on human health, considering the natural occurrence and enrichment of fermented fruit-based beverages in phenolic compounds, vitamins and minerals, and pro/prebiotics. The health benefits of fruit-based beverages that resulted from lactic, acetic, alcoholic, or symbiotic fermentation and specific daily recommended doses of each claimed bioactive compound were also highlighted. The latest trends on pre-fermentative methods used to optimize the extraction of bioactive compounds (maceration, decoction, and extraction assisted by supercritical fluids, microwave, ultrasound, pulsed electric fields, high pressure homogenization, or enzymes) are critically assessed. As such, optimized fermentation processes and post-fermentative operations, reviewed in an industrial scale-up, can prolong the shelf life and the quality of fermented fruit beverages.

Sensory and Physicochemical Properties and Stability of Folic Acid in a Pineapple Ready-to-Serve Beverage Fortified with Encapsulated Folic Acid

Fortification of food and beverages with folic acid is carried out frequently as a remedy to folic acid deficiency which causes serious health issues. This study was carried out to investigate the effect of incorporation of folic acid encapsulated alginate submicron particles in pineapple ready-to-serve (RTS) beverages. The encapsulation efficiency and loading capacity of the particles were 91.54 ± 0.45% and 1.02 ± 0.01%, respectively. The photostability and thermal stability studies of folic acid revealed that encapsulation poses a protective effect on folic acid and that dark and refrigerated conditions contribute to higher stability of folic acid. In this study, sensory evaluation of the RTS beverages was carried out through both ranking tests and acceptance tests using a five-point hedonic scale. The sensory panel showed the highest preference to pineapple RTS with incorporated encapsulated folic acid at a quantity of its recommended daily intake (400 µg/200 mL) before heat treatment. Shelf-life evaluations were carried out through measuring physicochemical properties, and pH, titratable acidity, and total soluble solids showed negligible or acceptable changes over two months. Folic acid degradation occurred due to heat treatment, but encapsulation in alginate submicron particles provided heat stability to folic acid. Thus, microencapsulated folic acid may be a successful carrier of folic acid which can be incorporated in beverages such as fortified pineapple RTS.

Stabilization and attributive amelioration of sugarcane juice by naturally derived preservatives using aonla and moringa extract

Sugarcane juice (SCJ) is a cheap, popular, and very nutritious beverage served at roadside stalls in many countries during harvesting season. The juice is normally consumed immediately after extraction as fermentation sets within a few hours of extraction. Preserving the raw sugarcane juice is always challenging because it spoils within a few hours of extraction due to fermentation. Therefore, the bottling, distribution, and marketing of sugarcane are difficult tasks. The present study was designed to investigate the effect of naturally derived preservatives using aonla extract (AE) and moringa extract (ME) in different proportions (0%, 3%, 5%, and 7%) for the preservation of SCJ during 21 days of the storage period at 4 ± 2°C temperature. The effect of extracts and storage time were analyzed on physicochemical parameters, bioactive compounds, enzymatic, microbiological, and sensory analyses of SCJ. A significant improvement in pH of 5% AE (5.30 ± 0.06) and 5% ME (5.36 ± 0.02) was observed at 21 days as compared to control (5.89 ± 0.02). The total phenolic contents in 7% ME were also observed to be retained (4.4 ± 0.02 mg GAE/mL) at 21 days as compared to control (2.65 ± 0.03 mg GAE/mL). Other physicochemical and phytochemical analyses including titratable acidity, total soluble solids, total flavonoids, ascorbic acid, 2,2-Diphenyl-2-picrylhydrazyl (DPPH), and ferric reducing antioxidant power assay (FRAP) also indicated that SCJ treated with ME was significantly stable (p < .05) regarding quality parameters, nutritional and sensory attributes at different storage intervals. These findings may be practical for the large-scale production, storage, and marketing of SCJ products.

Effect of Cryoconcentration Assisted by Centrifugation-Filtration on Bioactive Compounds and Microbiological Quality of Aqueous Maqui (Aristotelia chilensis (Mol.) Stuntz) and Calafate (Berberis microphylla G. Forst) Extracts Pretreated with High-Pressure Homogenization

The objective of this study was to evaluate the effect of cryoconcentration assisted by centrifugation-filtration on the bioactive compounds and the microbiological quality of aqueous maqui (Aristotelia chilensis (Mol.) Stuntz) and calafate (Berberis microphylla G. Forst) extracts pretreated with high-pressure homogenization (HPH). Aqueous extracts were prepared from fresh fruits which were treated with HPH (predefined pressure and number of passes). The best pretreatment was determined by aerobic mesophilic, fungal, and yeast counts. Treated extracts were frozen at −30 °C in special tubes and centrifuged at 4000 rpm for 10 min to obtain the cryoconcentrated product. The optimal pretreatment conditions for HPH were 200 MPa and one pass in which the extracts exhibited no microorganism counts. Cryoconcentration by freezing and subsequent centrifugation-filtration in a single cycle showed high process efficiency (>95%) in both soluble solids and bioactive compounds (total polyphenols and anthocyanins) and antioxidant capacity of the fresh fruits and extracts. The HPH treatment and subsequent cryoconcentration assisted by centrifugation-filtration is an efficient technology to obtain concentrates with good microbiological quality and a high content of bioactive compounds.

Effect of Food Processing on Antioxidant Potential, Availability, and Bioavailability

Antioxidants are understood to play a key role in disease prevention; because of this, research and interest in these compounds are ever increasing. Antioxidative phytochemicals from natural sources are preferred, as some negative implications have been associated with synthetic antioxidants. Beans, nuts, seeds, fruits, and vegetables, to name a few, are important sources of phytochemicals, which have purported health benefits. The aforementioned plant sources are reportedly rich in bioactive compounds, most of which undergo some form of processing (boiling, steaming, soaking) prior to consumption. This article briefly reviews selected plants (beans, nuts, seeds, fruits, and vegetables) and the effects of processing on the antioxidant potential, availability, and bioavailability of phytochemicals, with research from our laboratory and other studies determining the health benefits of and processing effects on bioactive compounds.

Combined modified atmosphere packaging and guar gum edible coatings to preserve blackberry (Rubus glaucus Benth)

Blackberry fruits are fresh products with wide market possibilities but of very limited shelf life (3-6 days). To develop preservation alternatives, the effect and interaction of a modified atmosphere packaging and an edible coating based on guar gum were determined on the shelf life and quality properties of blackberry cv. Castilla stored at 5 ℃. Three types of packaging were evaluated: (1) perforated polyethylene terephthalate clamshells, (2) sealed polyethylene terephthalate clamshells, and (3) sealed polyethylene terephthalate clamshells with a polylactic acid film on top. In turn, two types of coating were evaluated: coatings of guar gum solutions at (1) 0.3% and (2) 0.4% in water. During storage, an index of deterioration and different quality properties were evaluated. In the polyethylene terephthalate packages with polylactic acid, an equilibrium modified atmosphere packaging was formed. Weight loss was much lower for the sealed polyethylene terephthalate and polyethylene terephthalate + polylactic acid (<2%) compared to fruits in perforated clamshells, with no significant differences between these two types of packaging. It was possible to observe the treatment with an edible coating of 0.3% gum guar and perforated clamshells (guar gum 0.3/N) presented the lowest deterioration rate and preserve the fruit longer time (13 days) although with a high weight loss (23.23%) while the treatment with polyethylene terephthalate and polylactic acid film + edible coating of gum guar (guar gum 03/polylactic acid) kept the samples during 12 days with a lower weight loss (1.75%). This latter combination of equilibrium modified atmosphere packaging with a biodegradable film and the guar gum edible coating can be an interesting treatment from a commercial point of view.

Ultrasonic and microwave treatment improved jujube juice yield

The methods to leaching juice from dried jujube using six treatments and some factors related with juice yield such as total soluble solids (TSS), pectinase activity, pectin contents, galacturonic acid, and the microstructure morphology of cell were investigated. Six treatments including natural leaching, ultrasonic, microwave, ultrasonic before microwave, ultrasonic after microwave, and pressing directly were applied to extract juice. The group which treating with ultrasonic before microwave displayed its total soluble solids (TSS) was 16 °Brix, which was 6.67% higher than that of natural leaching. And its total soluble solids (TSS) reached to equilibrium in 2 hr, which was faster than that of natural leaching. The mechanism of improving the production efficiency of juice yield using ultrasonic combined with microwave was explored accordingly. The content of pectin and galacturonic acid increased by 58.52% and 59.01%, respectively, which were the highest among all samples. The activity of pectinase was 9.71 μg/(h·g), which was significantly decreased 40.23% as compared to natural leaching. And the treated cells became shriveled and pitted, which led to the leakage of the contents of cell. Thus, the result showed that treating with ultrasonic before microwave displayed the best juice yield. Ultrasonic cooperate with microwave was an efficient method to leaching juice from dried jujube.

Cherry extracts attenuate inflammation and oxidative stress triggered by monosodium urate crystals in THP-1 cells

The microwaves-assisted extraction (MAE) for concentration of cherry phytochemicals has seen explored. Polyphenols from cherries, Prunus avium (L.) L., were extracted using a microwave oven at 2,450 MHz, 453 W for a period of 60 s (T60), and was compared versus an unprocessed MAE extract (T0). The extracts were analyzed for total polyphenols, total anthocyanins, and antioxidant capacity. THP-1 cells were stimulated with monosodium urate (MSU) crystals at 150 µg/ml for 24 hr. Cherry extracts were added to cultures concurrently with MSU or 3 hr before MSU addition as pretreatments. Reactive oxygen species (ROS), IL-1β levels, and MSU crystal phagocytosis were evaluated. T60 extract showed a higher concentration of polyphenols, anthocyanins, and antioxidant activity than T0 extract. ROS were inhibited using the 1:800 and 1:1,600 (v:v) dilutions from both extracts, even used as pretreatments. IL-1β levels and MSU crystal phagocytosis were reduced. Cherry is a source of polyphenolic compounds with antioxidant and anti-inflammatory activity. PRACTICAL APPLICATIONS: The cherries and a cherry extract obtained via MAE has benefits as a possible coadjuvant to conventional gout therapy due to attenuate the inflammation and the oxidative stress triggered by monosodium urate crystals in THP-1 cells, which mimic an acute episode of gout.

An Overview of Effects Induced by Pasteurization and High-Power Ultrasound Treatment on the Quality of Red Grape Juice

In juice processing, ultrasound treatment has been tested as a potential alternative to conventional thermal methods to inactivate microorganisms and to enhance the nutritional status of juice. In this study, the impact of pasteurization and high-power ultrasound treatment on the quality of red grape juice was investigated in terms of the content of bioactive compounds such as phenolic compounds and l-ascorbic acid as well as regarding the microbiological and physicochemical properties. The grape juice was subjected to pasteurization (80 °C, 2 min) as well as to ultrasound treatment with an amplitude of 50 and 70% for 5 and 10 min. The results indicated the same level of total phenolic content for pasteurized and sonicated samples for 10 min with an amplitude of 70%, while the highest level of l-ascorbic acid was recorded for sonicated samples with an amplitude of 70% for 10 min. pH of sonicated samples decreased with amplitude and treatment time while total soluble solids and titratable acidity increased with amplitude and time. Moreover, the results indicated the usefulness of juice sonication to enhance the inactivation of microorganisms. Thus, the high-power ultrasound treatment might represent a viable technique to replace the conventional thermal treatment in grape juice processing.

Lactic Fermented Fruit or Vegetable Juices: Past, Present and Future

Numerous traditional low-alcohol fermented beverages produced from fruit or vegetables are described around the world. Fruit and vegetables and lactic fermented products both present nutritional benefits, which give reasons for the recent expansion of non-dairy lactic fermented juices on the market. In addition, fruit and vegetable juices are new carriers for probiotic bacteria. Specific phenotypic traits of lactic acid bacteria (LAB) are required so that LAB can effectively grow in fruit or vegetable juices, increase their safety and improve their sensory and nutritional quality. From the diversity of microbiota of spontaneous fermentations, autochthonous starters can be selected, and their higher performance than allochthonous LAB was demonstrated. Achieving long-term storage and constant high quality of these beverages requires additional processing steps, such as heat treatment. Alternatives to conventional treatments are investigated as they can better preserve nutritional properties, extract bioactive compounds and promote the growth and metabolism of LAB. Specific processing approaches were shown to increase probiotic viability of fruit and vegetable juices. More knowledge on the metabolic activity of lactic acid bacterium consortium in fruit or vegetable juices has become a bottleneck for the understanding and the prediction of changes in bioactive compounds for functional beverages development. Hopefully, the recent developments of metabolomics and methods to describe enzymatic machinery can result in the reconstruction of fermentative pathways.

Recent advances in ultrasound application as a novel technique in analysis, processing and quality control of fruits, juices and dairy products industries: A review

Recently, ultrasound has been widely used in the researches in the food science and technology. Among the food materials, fruits, juices and dairy products are strongly sensitive to ultrasound-based techniques. In this review paper, applications of ultrasound in terms of high and low-power modes in processing, instrumentation and control of the industrial operations are studied in the fruit, juice and dairy sectors of the food science and technology by emphasizing the principles of these techniques and their physicochemical effects on the products. Also, a comprehensive analysis of these methods and important factors influencing their performance are presented, along with the advantages and the drawbacks of each ultrasound-assisted techniques. The solutions for better productivity of this technique would be presented and future trend of this technology would be outlined. By studying the latest researches and advances in the field of ultrasound applications, it has been confirmed that this technique can be helpful in accelerating processes, reducing energy requirements, increasing productivity, and producing better quality food materials in the fields of fruits, juices and dairy products. Notwithstanding, in order to solve the challenges ahead, and for potential applications of ultrasound technology, further researches need to be expanded in the areas mentioned. Also, with the advancement of technology, more advanced equipment, ultrasound transducers and instrumentations would be introduced that needs to be applied in this regard, to solve the current challenges.

Effect of an Edible Coating Based on Chitosan and Oxidized Starch on Shelf Life of Carica papaya L., and Its Physicochemical and Antimicrobial Properties

Papaya production plays an important economic role in Mexico’s economy. After harvest, it continues to ripen, leading to softening, skin color changes, development of strong aroma, and microbial spoilage. The objective of this work was to apply an active coating of chitosan–starch to increase papaya shelf life and to evaluate physicochemical and antimicrobial properties of the coating. Papaya surfaces were coated with a chitosan-oxidized starch (1:3 w/w) solution and stored at room temperature (25 ± 1 °C) for 15 days. Variables measured were color, titratable acidity, vitamin C, pH, soluble solids, volatile compounds by gas chromatography, texture, homogeneity by image analysis, and coating antimicrobial activity. At the end of the storage time, there were no significant differences (p > 0.05) between coated and uncoated papayas for pH (4.3 ± 0.2), titratable acidity (0.12% ± 0.01% citric acid), and soluble solids (12 ± 0.2 °Bx). Papaya firmness decreased to 10 N for coated and 0.5 N for uncoated papayas. Volatile compounds identified in uncoated papaya (acetic acid, butyric acid, ethyl acetate, ethyl butanoate) are related to fermentation. Total microbial population of coated papaya decreased after 15 days, whereas population of uncoated papaya increased. This active coating permitted longer shelf life of papaya than that of the uncoated fruit.