• Food Science and Preservation
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• v.19 no.5
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• pp.712-719
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• 2012

In this study, the physicochemical and physiological activities of 10 different commercially available juices (apple juice-A: cloud type; apple juice-B: clear type; blueberry juice; grape juice-A; grape juice-B; orange juice-A; orange juice-B; pineapple juice; pomegranate juice; and tomato juice) were investigated. The average pH, titratable acidity, Brix, and reducing sugar were 3.57, 0.57%, $13.1^{\circ}Brix$, and 57.58%, respectively. The total polyphenol and flavonoid contents were within the ranges of 98.29-878.12 ug/mL and 23.82-156.63 ug/mL, respectively, and pomegranate juice showed the highest content, followed by blueberry juice and apple juice-A. In the DPPH radical scavenging assay, apple juice-A, grape juice-A, and pomegranate juice exhibited the highest activity (greater than 90%) while orange juice-B, pineapple juice and tomato juice showed the weakest. The tyrosinase inhibitory effect was highest in apple juice-A, followed by orange juice-A and blueberry juice. The reducing power was highest in pomegranate juice and lowest in pineapple juice and grape juice-A. The antioxidant activity by reducing power was highly correlated with the total polyphenol content.

• The Korean Journal of Mycology
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• v.5 no.1
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• pp.27-31
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• 1977

In brewing of apple wine, the effect of maceration of Ralls apple to apple juice quantity and apple wine taste were studied. The results are summerized as follow; 1. The yield of juice was increased by the maceration but maceration decreased acid contents in juice by the action of the enzymes in apple tissues. 2. The quality of apple wine produced from maceration of fresh pulp was found to be equeal or superior to those obtained from none-macereration treatment. 3. During fermentation period, no significant difference in mash components (alcohol, sugar content, acid, pH and color) existed among treatments.

• The Korean Journal of Food And Nutrition
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• v.11 no.1
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• pp.1-5
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• 1998

The purpose of this study was to investigate the chemical and sensory properties of Kimchi added apple Juice. Kimchi added amount of 0, 5 and 10% of apple juice was fermented at 4$^{\circ}C$ for 20 days. During the fermentation, pH was lowered in all Kimchi samples and pH of Kimchi added apple juice was a little lower than that of Kimchi without apple juice. Acidity was increased continuously and saltiness was maintained at 1.6~2.3% levels during fermentation. Although reducing sugar was increased in the early stage of fermentation, it was decreased subsequently as fermentation proceeded. Also the reducing sugar of Kimchi added apple juice was relatively higher than the other sample. Total vitamin C(Vit C) of Kimchi added apple juice was reduced in the early stage of fermentation and increased gradually after 10 days. As a result of the sensory evaluation, Kimchi added 5% of apple juice, was showed high scores in taste, flavor, texture and overall acceptability in the early stage of fermentation.

• Food Science and Preservation
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• v.21 no.2
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• pp.199-205
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• 2014

This study was conducted to investigate the physicochemical properties and antioxidant activity of black Doragi-apple juice to increase the utilization of Doragi, which is known as a high-functional horticultural crop. To prepare the black Doragi, it was steamed for 15 days at $60^{\circ}C$ and was then dried at $30^{\circ}C$ for 3 h. The five types of black Doragi-apple juice were prepared based on different mixing ratios of black Doraji extract, apple extract, and jujube extract. The mixing ratios of black Doraji extract, apple extract, and jujube extract were 3:3:1, 4:2:1, 2:4:1, 2:2:1, and 2:6:1 for samples A, B, C, D, and E, respectively. The pH and acidity of black Doragi-apple juice were within the ranges of 3.9-4.15 and 1.26-1.51%, respectively. Black Doraji-apple juice E showed the highest sugar content (9.33 $^{\circ}Brix$), reducing sugar content (85.05 mg/mL), and sugar content/acid ratio (6.98). Based on the sensory evaluation, sample C was most preferable in terms of color, taste, sugar-acid ratio, and overall preference, except for the flavor. Black Doragi-apple juice D showed a higher total polyphenol content (706 ${\mu}g/mL$) than sample C (586.22 ${\mu}g/mL$), but there was no statistically significant difference between samples C and D in terms of antioxidant activities. Therefore, it is suggested that the best mixing ratio of black Doraji extract, apple extract, and jujube extract for the production of the best black Doragi-apple juice with excellent taste and antioxidant activities is 2:4:1 (sample C).

• Korean journal of food and cookery science
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• v.25 no.6
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• pp.747-757
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• 2009

The purpose of this study was to enhance the quality of kochujang Apple juice was added to traditional Kochujang at 0%, 20%, 40%, 60 and 80%. Physicochemical and microbial characteristics were periodically investigated during at room temperature during a 90 day fermentation period. The moisture content of the apple Kochujang was higher than that of the control, while the salt content of the apple Kochujang was lower than that of the control, At first, the sweetness of the apple Kochujang showed no significant difference from the control; however, its sweetness increased during the 90 days. In all treatments, the pH value decreased during the fermentation period, while the titratable acidity increased during the fermentation period. Viscosity decreased greatly after 30 days. Sugar reduction was higher in the apple Kochujang than in the control, and its concentration increased with apple juice content. According to the analysis of free sugar, glucose, fructose, and maltose had an especially high ratio in the apple Kochujang. The organic acids detected in Kochujang were citric acid, malic acid, oxalic acid and lactic acids. The content of citric acid and malic acid were higher than the other acids in the apple Kochujang. L, a, and b values generally decreased during the fermentation period. When the Kochujang was made, the number of the total viable cells was $10^7\;CFU/g$. At room temperature, the number steadily increased up to the 30th day, then steadily decreased on the 90th day. After that, there was no significant change. The number of yeasts was $10^6\;CFU/g$ at the end of the 90th day. After the 90th day of fermentation, sensory results showed that the 60~80% apple juice Kochujang showed the best taste, appearance, texture, and overall quality.

• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1433-1436
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• 2000

The effect of addition of pectin on the stability of casein solution was studied to apply casein-pectin mixture to apple juice. The solubility of 0.1% casein solution was below 20% at pH 3-5. However, the solubility of 0.1% casein-0.1% pectin mixtures was over 70% at pH 2-10. The increase in the concentration of casein-pectin mixture showed adverse effect on the solubility. The apple juice (pH 3.4), containing 0.1-0.5% casein-pectin mixtures, remained stable without the precipitation of casein. The stability of apple juice including casein-pectin mixture was maintained upon heating at $100^{\circ}C$ for 10 minutes or refrigerating for a week. This study suggested the possibility of protein fortification to acidic beverages since casein-pectin mixture maintained stability in apple juice.

• Food Science and Preservation
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• v.30 no.5
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• pp.743-757
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• 2023

The formulation of a novel functional fresh apple juice enriched with dietary prebiotic fiber (inulin or polydextrose), ginger extract (GE), and cardamom essential oil (CEO) was carried out based on a combined D-optimal design. In the first stage, sensory evaluation was performed to screen and select the optimum sample for further experiments. The sensory evaluation showed that the sample containing inulin 0.25 g/100 g GE and 0.03 g/100 g CEO had the highest organoleptic score. In the second stage, various chemical experiments, including pH, acidity, formalin index, total phenol, flavonoids, antioxidant capacity, and vitamin C content, were evaluated on the selected enriched apple juices. The addition of GE and CEO caused changes in nutritional characteristics, including antioxidant capacity, total phenol, flavonoids, vitamin C, and IC50, from 35 g/100 g, 350 mg GAE/g, 17 mg/L, 370 mg/kg, and 1,800 mg/kg to 45 g/100 g, 460 mg GAE/g, 21 mg/L, 420 mg/kg, and 1,200 mg/kg respectively. The steady shear flow and dynamic oscillatory shear rheological tests were also performed on the screened samples, and results showed that the addition of dietary fiber in apple juices increased the apparent viscosity, storage modulus, loss modulus, and complex viscosity. In general, adding plant extracts and processed essential oil to apple juice increased the nutritional-nutraceutical value and sensory attributes of apple juice.

• Preventive Nutrition and Food Science
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• v.19 no.2
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• pp.108-114
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• 2014

Four Korean kernel fruit (apple, pear, persimmon, and mandarin orange) juices were obtained by household processing techniques (i.e., blending, juicing). Whole and flesh fractions of each fruit were extracted by a blender or a juicer and then examined for phytochemical content (i.e., organic acids, polyphenol compounds). The antioxidant capacity of each juice was determined by ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays. Results revealed that juices that had been prepared by blending whole fruits had stronger antioxidant activities and contained larger amounts of phenolic compounds than juices that had been prepared by juicing the flesh fraction of the fruit. However, the concentration of ascorbic acid in apple, pear, and mandarin orange juices was significantly (P<0.05) higher in juice that had been processed by juicing, rather than blending. The juices with the highest ascorbic acid (233.9 mg/serving), total polyphenols (862.3 mg gallic acid equivalents/serving), and flavonoids (295.1 mg quercetin equivalents/serving) concentrations were blended persimmon juice, blended mandarin orange juice, and juiced apple juice, respectively. These results indicate that juice extraction techniques significantly (P<0.05) influences the phytochemical levels and antioxidant capacity of fruit juices.

• Food Science and Biotechnology
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• v.15 no.3
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• pp.347-350
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• 2006

The objective of this study was to investigate the possible effects of oral administration of single cell products (SCP) of apple on activating peritoneal macrophages. Apples were processed either for cold-pressed juice or SCP, which were produced by incubating sliced apples with a protopectinase, Sumyzyme MC. Both cold-pressed juice and SCP of apple were administered to C57BL/6 mice for 10 days to compare their efficacy, along with the control group, in stimulating peritoneal macrophages. The viability of macrophages was significantly increased by up to 161% of that of the control following the administration of apple SCP, whereas the viability of macrophages was increased to a lesser extent of up to 143% in the apple juice (AJ) administered group. Administration of apple SCP also induced a significantly higher production of $H_2O_2$ from macrophages (317% of the control) than that of cold-pressed AJ (210%). Although nitric oxide (NO) production was not increased by the administration of either AJ or SCP, the latter slightly but significantly increased tumor necrosis factor-${\alpha}$ ($TNF-{\alpha}$) production from macrophages from 560.4 to 579.8 pg/mL. The results of this study suggest that administering SCP is more efficient than administering AJ to stimulate functions of peritoneal macrophages.

• Korean Journal of Food Science and Technology
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• v.30 no.1
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• pp.184-191
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• 1998

Gel-type fermented milk was prepared from mixture of milk and apple juice or grape juice by fermentation with Lactobacillus acidophilus (KCTC 2182). Changes in volatile aroma compounds during 21 hr-lactic fermentation were studied. Diacetyl and acetoin, that were produced by L. acidophilus, were detected at 6 hr or 12 hr and showed peak values at 12 hr. Acetone and butanol, that were present originally in sample, decreased gradually during fermentation. Ethanol, that was either present originally in sample or produced by L. acidophilus, showed peak value at 18 hr in case of mixture of apple juice and milk. The concentration of ethanol was substantially high during whole period of fermentation in case of mixture of grape juice and milk though it showed peak value at 18 hr. Because the concentrations of ethanol in apple juice and ethanol and acetone in grape juice were relatively high, it might affect the results.