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In this work, to evaluate the role of acidic electrolyzed water (AEW) combined with vacuum precooling (VP) treatment in fresh goji preservation, the physicochemical properties and anti‐oxidation indexes of goji berries were compared between the AEW+VP‐treated and control (VP treatment) groups during storage at 4, 7, and 10°C. The results showed that AEW+VP could effectively inhibit the decrease in L* and a* values, reduce the respiratory rate, delay the loss of vitamin C content, and maintain higher total soluble solid (TSS) content. Compared to the control, AEW+VP‐treated goji maintained higher catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD) activity. Therefore, AEW+VP treatment could effectively improve the storage quality and extend the shelf life of fresh goji berries. Practical applications: Acidic electrolyzed water, a clean and environmentally friendly preservation technology, combined with vacuum precooling extended the shelf life of fresh goji berries while delaying the aging of goji berries at different storage temperatures. In this sense, AEW+VP had certain stability in enhancing the storage quality and extending the shelf life of goji berries, which can be regarded as an effective strategy for promoting the preservation of agricultural products. [ABSTRACT FROM AUTHOR]

The study aimed to characterize bananas in their different stages of ripeness, to determine the variables that demonstrate higher levels at each moment. The fruits were analyzed according to physical parameters: weight, texture, and diameter of the fruits; as well as physicochemical parameters: pH, titratable acidity, soluble solids, and Ratio; and also biochemical parameters: total sugars, phenolic compounds, ascorbic acid, pigments, antioxidant activity by DPPH and FRAP methods. The used samples were collected at the following maturation stages: 2, 4, 6, and 7 and determined according to the Von Loesecke Maturation Scale. In relation to the behavior of the parameters evaluated, the fruits showed significant reductions in relation to the physical parameters, while there were increases in relation to pH, titratable acidity, and soluble solids. The antioxidant and phenolic activities also showed reductions, which shows that the degradative process caused by ripening also causes reductions in these compounds. [ABSTRACT FROM AUTHOR]

The objective was to correlate the impacts of the cooking process of fresh fruits (innatura) on the content of bioactive compounds (ascorbic acid, phenolic compounds, flavonoids, carotenoids and anthocyanins, lycopene, and β‐carotene), on antioxidant activity (2,2‐diphenyl‐1‐picrylhydrazyl [DPPH] and ferric reducing antioxidant power [FRAP]), and in agro‐industrial parameters related to yield and quality in nine varieties of tomatoes. It was possible to verify, at the end of the experiment, from the data obtained that, for most of the analyzed bioactive parameters, there are positive correlations between them and both DPPH and FRAP antioxidant activity. The correlations that occurred between carotenoids, lycopene and β‐carotene, and between flavonoids and anthocyanins were emphatic. As for the performance of the tomato varieties, mainly in relation to bioactive compounds, both innatura and processed tomatoes were similar, that could be evidenced by the high positive correlations and demonstrated approximations. Practical applications: Bioactive compounds in food have been credited with the ability to exert influences such as increasing antioxidant activity that prevents cell deterioration, reducing the risks of various diseases, such as cancer, stimulating the immune system, balancing hormone levels, and also having antibacterial and antiviral activity. The responses to the behavior of these compounds in vegetables, when processed, and their interactions, support the moment of choosing a variety to be subjected or not to processing. The agro‐industrial parameters related to yield and quality, and also their correlations, are important because they show how the tomato varieties behave when subjected to thermal processing. [ABSTRACT FROM AUTHOR]

Pulsed magnetic field (PMF, 5–7 T, 5–30 pulses) was applied to orange juice to evaluate its effects on inactivation of microbiota and enzyme and quality attributes. PMF decreased the activities of mesophilic baceria and yeast and mold by the highest log reduction of 0.61 at 7 T with 20 pulses and 0.36 at 7 T with 30 pulses, respectively. Peroxidase (POD) and pectin methylesterase (PME) activities were partially inactivated. PMF showed a good potential to inactivate PME and the lowest residual activity of PME was 50.28% obtained at 6 T with 20 pulses. No significant change in soluble solids and small changes in the pH, titratable acidity, and color were observed after PMF treatment. PMF brought about a slight decrease of ascorbic acid, phenolic compounds, and antioxidant capacity (DPPH​ and ABTS) in orange juice. Therefore, PMF appears to be a promising technogy involving microbial and enzymic inactivation with small changes in juice quality. Novelty Impact Statement: Pulsed magnetic field could inactivate mesophilic bacteria and yeast and mold in orange juice. Pulsed magnetic field had a good potential to inactivate pectin methylesterase in orange juice. The minor quality degradation in orange juice was observed after pulsed magnetic field treatment. [ABSTRACT FROM AUTHOR]

Stevia leaves have been claimed to possess the highest antioxidant capacity among botanic foods, yet the antioxidant activity has been attributed to the polyphenols from Stevia leaves (PPS). However, most studies about the PPS were based on Stevia extracts that contain abundant polyphenols and flavonoids. The PPS excluded flavonoids were found to possess antioxidant activity similar to that of epigallocatechin gallate, demonstrating stronger hydrophilic antioxidant activity and stability than that of ascorbic acid (VC), vitamin E, or chlorogenic acid under the assayed circumstances. Both of the PPS and their antioxidant activity are very stable in various physical environments, but less stable in the presence of potassium sorbate or sucrose. Moreover the combination of PPS and VC could increase the antioxidant stability of either VC or PPS. Therefore, the PPS have the potential to be a natural, inexpensive, and abundant antioxidant that can be utilized in the pharmaceutical and cosmetics. Practical applications: The PPS excluded flavonoids were found to possess antioxidant activity similar to that of epigallocatechin gallate, demonstrating stronger hydrophilic antioxidant activity and stability than that of ascorbic acid (VC), vitamin E, or chlorogenic acid under the assayed circumstances. Both of the PPS and their antioxidant activity are very stable in various physical environments, but less stable in the presence of potassium sorbate or sucrose. Moreover the combination of PPS and VC could increase the antioxidant stability of either VC or PPS. Therefore, the PPS have the potential to be a new natural, inexpensive, and abundant antioxidant that can be utilized in the pharmaceutical and cosmetics. [ABSTRACT FROM AUTHOR]

Olive mill wastewater (OMW) was used as a source to extract radical scavenging compounds, in order to study their possible valorization as natural antioxidants. Their antioxidant activity (IC50 0.32 µg/ml) was found to be more potent than that of a commercial antioxidant: Ascorbic acid (AA) (IC50 1.91 µg/ml). The olive mill wastewater extract (OMWE) and AA were separately added to two vegetable oils, sunflower oil and rapeseed oil. These oils were then put under simulated storage conditions (accelerated test at 60°C) for 4 weeks. The physicochemical parameters, analysis of fatty acids, phytosterols, and tocopherols were the key parameters used to monitor the evolution of the oxidation state. The results obtained showed that the oils treated with the OMWE underwent oxidative deterioration slower than that of the control (without additives), and that phytosterols and tocopherols content decreased as a function of storage time following first‐order kinetics. The use of the OMWE helped reduce the loss of both phytosterols and tocopherols in 4 weeks by half compared to the control samples, with the exception of total phytosterols in rapeseed oil where the loss reduction was not as important (about 2% loss reduction). Practical application: Antioxidants are widely used in the food industry, as they prevent the development of rancid aromas that lead to harmful consequences during storage and cooking. The practical implication of the study is that natural radical scavenging compounds extracted from OMW can be efficiently used to enhance the quality and safety of refined oils stored at high temperature conditions. [ABSTRACT FROM AUTHOR]

Abstract: The effects of peeling, drying temperatures (55–65 °C), and pretreatment with sodium metabisulfite (SMS) on the physicochemical characteristics and antioxidative activities of Asian pear powder were investigated. The powders from SMS‐treated peeled and unpeeled pears (PSP and USP, respectively) had higher L* values and water absorption indices than peeled and unpeeled pears without SMS treatment (PP and UP, respectively) at different drying temperatures. However, the water solubility indices of PSP and USP were lower than those of PP and UP at low temperatures and water solubility increased as drying temperatures increased. Total phenolic, ascorbic acid, chlorogenic acid, and caffeic acid contents and antioxidative activities were higher in USP and UP than in PSP and PP and, with the exception of ascorbic acid, increased with increasing drying temperature. The arbutin content of UP was higher than that of PP and was not influenced by drying temperatures and SMS pretreatment. In conclusion, SMS treatment before drying at 65 °C could result in higher quality Asian pear powder. Practical applications: Asian pear fruits are rich in various antioxidants and are good sources of sugars. Therefore, they have been developed as food ingredients and are widely used in various foods, including cakes and biscuits. It is necessary to study optimal pretreatment conditions and drying temperatures to retain more functional components in Asian pear powder. Our study demonstrates optimal conditions to produce high quality Asian pear powder that can be used in various food formulations to improve nutritional value, flavor, color, and sweetness. [ABSTRACT FROM AUTHOR]

Abstract: Vacuum‐assisted freeze concentration is a technology allows produces high‐quality concentrates and thus achieves the protection of heat‐labile components in fresh samples. The aim of this study was to investigate the use of vacuum‐assisted block freeze concentration in the elaboration of orange juice. Fresh juice was unidirectional frozen at −20 °C for 12 hr and vacuum was performed at 80 kPa. The results showed, 20 min of suction, an increased in concentrated fraction and ascorbic acid content by 4.4 and 4.1 times, respectively, compared with the fresh juice. The cryoconcentrates were darker than the initial sample, with ΔE* values >10 CIELAB units in all treatments. In addition, achieved high values with 84% in efficiency and 35% of concentrate. It was concluded that vacuum in freeze concentration of orange juice was effective for obtaining a high‐quality concentrate with a higher concentration of solids and ascorbic acid content compared with the fresh sample. Practical applications: The block freeze concentration assisted by vacuum allows producing an orange juice concentrate with excellent physicochemical properties (increase solid content, darker color, and higher ascorbic acid content compared with the initial sample), which can draw attention to consumers looking foods rich in bioactive components for a healthy life. The vacuum as an assisted technique improve the process parameters of block freeze concentration, obtaining promissory results for adaptability to commercial scale in the elaboration of concentrated orange juice. [ABSTRACT FROM AUTHOR]

Abstract: The objective of current study was to characterize nine well‐known fruits according to their antioxidant properties and quality parameters for potential use of beverage application. Fruits included in this study are aronia, blueberry, cherry, cranberry, mangosteen, omija, raspberry, rambutan, and strawberry. The polyphenols (total phenolic compounds and anthocyanins) and antiradical activity as well as other quality attributes were analyzed. The antioxidant activities of these fruit products were significantly different (p < .05) in that rambutan had the highest total phenolic compounds (9,034 mg GAE/100 g), followed by aronia (6,001 mg GAE/100 g, p < .05). Cranberry demonstrated the strongest DPPH radical scavenging activities (52.4%), followed by aronia (35.9%), blueberry (33.3%), omija (33.5%), and raspberry (39.8%, p < .05). Blueberry had the highest vitamin C content (969.9 mg/100 mL). These fruits were classified into three distinctive groups according to their characteristics. Omija was found to be distinctively different from the other fruits in terms of its quality characteristics. Practical applications: This study evaluated the quality aspects of various fruits to select the potential ingredient for the ready‐to‐drink‐type beverage application. Current work demonstrated how each fruit is located in the quality and phenolics, and antiradical characteristics map, and this information can be practically assist future product developers who are utilizing fruits for their product formulation. [ABSTRACT FROM AUTHOR]

A novel combination of ascorbic acid (AA) and green tea extract (GTE) was tested for its ability to prevent browning of fresh cut Red Delicious apple slices. A concentration of 3% AA and 0.1% GTE was selected for definitive studies since it provided an optimum balance of antibrowning efficacy, taste, lack of staining, and cost. This combination prevented the browning of apple slices for up to 14 days; whereas, 3% AA prevented browning for only 4-6 days. In addition, GTE by itself caused noticeable staining of the apple slices; whereas, the combination did not stain the slices. Mechanistic studies demonstrated that the GTE helped to maintain AA levels, likely due to the GTE's own antioxidant and enzyme inhibition properties. In conclusion, AA and GTE exhibited a synergistic interaction in preventing the browning of fresh cut apple slices. Practical applications Fresh cut produce, such as apple slices, require a preservation method to prevent browning and premature degradation during storage. Sulfites are no longer allowed in the United States for this use and ascorbic acid requires very high concentrations for adequate and prolonged preservation. Other methods have been developed; however, they are often too complex for widespread and cost-effective use. The current research demonstrated that green tea extract dramatically potentiates the antibrowning effect of ascorbic acid and allows much lower levels of ascorbic acid to be used to achieve optimum antibrowning efficacy. In addition, complex packaging requirements are not needed to obtain the antibrowning effect. This novel formulation will allow much lower levels of ascorbic acid to be used, which will be a significant cost savings to producers and consumers. [ABSTRACT FROM AUTHOR]

Inhibitory effects of several antioxidants on the browning intensity of chicken protein-sugar Maillard reaction system were investigated. The results found that 1% (m/v) addition of NaCl had a certain effect on inhibiting browning, while only 0.5% (m/v) addition of L-cysteine can play a favorable role in browning inhibition. As for MRP samples with L-ascorbic acid, the browning inhibiting effect reaches the max with the L-ascorbic acid content of 0.3% (m/v). The A420 value of samples dried by spray drying process was higher ( P < 0.05) than those of chicken protein Maillard peptide and enzymatic hydrolysate dealt by freeze drying process. The electronic tongue analysis indicated that the umami substances of chicken protein Maillard peptide could be easily decompose in the process of storage, while those of enzymatic hydrolysate were stable. However, compared with the spray drying process, freeze drying process can better preserve umami substances. Practical Applications The inhibitory effect of several antioxidants, including NaCl, L-cysteine, polyphenols and L-ascorbic acid, on the browning intensity of chicken protein-sugar Maillard reaction system was identified. In the meantime, the effects of two kinds of drying technologies (spray drying technology and freeze drying technology) on the properties and browning intensity of Maillard peptides were also compared and discussed. Results obtained in this work can provide practical application in food industry. [ABSTRACT FROM AUTHOR]

Sim (Rhodomyrtus tomentosa) fruit is rich in antioxidants including phenolics and ascorbic acid. In this study, maltodextrin was used as encapsulating agent in spray drying of sim juice to yield the powder. The effects of core/wall ratio and inlet temperature of drying agent on the retention of antioxidants during the spray drying of sim juice were investigated. Decrease in core/wall ratio from 1:1 to 1:4 led to lower moisture content of the powder and higher retention of phenolics and ascorbic acid. Further decrease in core/wall ratio from 1:4 to 1:5 reduced the antioxidant retention due to high viscosity of the feed solution. When the inlet temperature of drying agent augmented from 150 to 180C, the moisture content of the powder decreased and the retention of antioxidants increased. Increase in inlet temperature from 180 to 190C had detrimental effect on the antioxidant retention during the spray drying of sim juice. [ABSTRACT FROM AUTHOR]

Apple juice was subjected to ultrasound treatment at 30, 60 and 90% amplitude levels using probe-type sonicator (20 kHz, 20C for 3 min) keeping pulse durations of 5 s on/off, and the samples were stored at 4C for 30 days. Effects of sonication and storage on total soluble solids (TSS), pH, titratable acidity, instrumental color (L*, a*, b*), nonenzymatic browning (NEB), cloud value, ascorbic acid and antioxidant capacity were evaluated. Additionally, sensory characteristics were also investigated. As results, TSS, pH and acidity remained unchanged while significant increases in color values, NEB, cloud value, ascorbic acid and antioxidant capacity were observed in all sonicated samples. Moreover, the consumer panel rated sonicated apple juice samples as most acceptable. Storage study showed significant increase in acidity, color values, NEB and decrease in pH, cloud value, ascorbic acid and antioxidant capacity. The results were further verified by principal component analysis. [ABSTRACT FROM AUTHOR]

Investigations were carried out to determine changes in physicochemical and microbial qualities of oven-dried, sun-dried and freeze-dried Ipomoea aquatica Forsk., a popular leafy vegetable (known as kangkung). Sun drying showed low retention of fat and fiber with insignificant changes in protein content, whereas, freeze-dried samples showed high retention of ascorbic acid. Results of 2,2- diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay showed higher inhibition in oven-dried samples, followed by freeze-dried and sun-dried samples. In addition, freeze-dried samples retained chlorophyll better among the three dried samples. Total bacteria, yeast and mold counts and Escherichia coli count in kangkung showed significant decrease on drying. [ABSTRACT FROM AUTHOR]

Changes in antioxidants, rehydration ratio and browning index of tomato slices (raw and blanched) coated with gum arabic of different concentrations (1, 5 and 10%) and dried by sun (40 ± 1 C) or air (80 C) were monitored during storage (6 months) at 24 ± 1 C. Sun- and air-drying of raw and blanched slices significantly ( P ≤ 0.05) increased the total phenolics, flavonoids and lycopene contents but significantly ( P ≤ 0.05) decreased ascorbic acid. Storage of dried coated raw and blanched slices increased total phenolics compared to uncoated. Flavonoids, ascorbic acid, lycopene and rehydration ratio were significantly ( P ≤ 0.05) decreased. However, coating of raw and blanched slices reduced the level of losses in antioxidants, color and rehydration ratio during drying and storage. As the concentration of gum arabic increased, the rate of reduction in antioxidants, color and rehydration ratio decreased, and there was a remarkable increase in some antioxidants during storage. Practical Applications Limited shelf life and loss in quality are major problems in marketing of fresh tomatoes. An ideal preservation method should increase the shelf life of tomatoes without causing notable loss of quality. Dehydration of tomato slices had a great impact on the constituents of the slices, but application of surface edible coating prior to dehydration reduced losses in fruit composition and kept the quality attributes of the final product. [ABSTRACT FROM AUTHOR]

ABSTRACT The effect of waxing and wrapping on fruit quality, phenolic compounds and antioxidant activity of two citrus cultivars (Satsuma mandarin [ Citrus unshiu Marc] and Hamlin orange [ Citrus sinensis Osbeck cv Hamlin]) stored at 10 ± 2C for 60 days was investigated. Ascorbic acid, flavanone glycosides, phenolic acids, total phenolics and antioxidant activity (ferric-reducing antioxidant power assay and 2,2-diphenyl-1-picrylhydrazyl free radical-scavenging assay) were determined. During storage, phenolic compounds were relatively stable. Antioxidant activity was influenced by both ascorbic acid and phenolic compounds. Generally, wrapping fruits retained higher levels of flavanones and phenolic acids during storage while waxing was not preferable in preserving phenolic compounds especially after 30 days. Besides, waxing and wrapping retained higher levels of total phenolics after 15 days of storage in both cultivars. PRACTICAL APPLICATIONS Recently, phenolic compounds of citrus fruits have gained much concern because of their benefits to human health. However, studies on changes of detailed phenolic components during postharvest storage are limited. The effect of waxing and wrapping on phenolic compounds and antioxidant activity of Satsuma mandarin ( C. unshiu Marc) and Hamlin orange ( C. sinensis Osbeck cv Hamlin) during storage are presented in this study. The results show that the two citrus cultivars maintained their functional value because of the stability of phenolic compounds during storage. Wrapping preserved higher levels of phenolic content with improved fruit appearance thus is better for marketing and consumption. While waxing had negative effects on keeping functional quality of fruit after long-time storage. The findings may also be useful for a better understanding of changes in specific phenolic compounds in citrus fruits during postharvest storage. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, the changes in color, ascorbic acid, antioxidant activity and phenolic compounds of raspberry and blackberry cultivars after marmalade processing were evaluated. For this purpose, raspberry fruits ( Rubus idaeus L.) of four cultivars (Aksu Kırmızısı, Rubin, Hollanda Boduru and Heritage) and blackberry fruits ( Rubus fruticosus L.) of three cultivars (Bursa 1, Bursa 2 and Chester) were used. According to the results, color values of blackberry cultivars and marmalades were lower than the color values of raspberry. Raspberry cultivars were more durable to thermal processing than blackberry cultivars in terms of ascorbic acid degradation. An 84.19% decrease was seen in the antioxidant activity of raspberry and blackberry cultivars after marmalade processing. The marmalade produced from Hollanda Boduru had the highest antioxidant activity. Ellagic acid was predominant in all raspberry and blackberry cultivars and ranged from 727.90 ± 9.21 mg/kg (Rubin) to 1,828.07 ± 23.73 mg/kg (Chester). None of the phenolics was determined in marmalades. PRACTICAL APPLICATIONS Berry fruits constitute a good source of natural antioxidant substances. Particularly, phenolic compounds contribute substantially to the antioxidant complement of many small fruit species, having potential health effects. The main contribution of this work is to determine the compositional changes of different blackberry and raspberry cultivars after marmalade production. [ABSTRACT FROM AUTHOR]

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