• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.375-379
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• 1999

This study was designed to develop non-thermal pasteurized fresh apple juice by applying pulsed electric field (PEF) treatment. The effect of non-thermal PEF treatment on physicochemical and sensory properties of apple juice was examined by measuring changes in vitamin C contents, colors, flavors and sensory properties. Color of PEF and heat treated apple juices was not significantly different from each other. Vitamin C content of PEF treated apple juice was close to that of fresh apple juice, but was much higher than that of heat treated apple juice. Heat treated apple juice lost 70% of flavor components, whereas PEF-treated apple juice lost only 15%. Sensory scores of PEF treated apple juice were significantly higher than heat-treated one in flavor, taste and overall acceptability. In conclusion, PEF treated apple juice had superior physico-chemical and sensory properties to heat-treated one.

• Food Science and Preservation
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• v.19 no.2
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• pp.178-184
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• 2012

The physiochemical property, nutrient composition, and functionality of apple juice sterilized at a low temperature (LT, $70^{\circ}C$, 30 min) or a high temperature (HT, $100^{\circ}C$, 20 min) were analyzed. The pH of the apple juice that was sterilized at LT (pH 4.72) was higher than that of the apple juice that was sterilized at HT (pH 4.57), and the acidity of the apple juice that was sterilized at HT (8.90%) was higher than that of the other sample. The sugar content of the two apple juice samples was 15 $^{\circ}Brix$, and the apple juice samples had high potassium, malic acid, and glutamic acid contents. The total polyphenol contents of the apple juice samples that were sterilized at LT and HT were 27.39 mg/100 mL and 23.24 mg/100 mL, respectively. The apple juice that was sterilized at LT had a significantly stronger DPPH radical scavenging activity than the apple juice that was sterilized at HT ($p$ <0.01), and the apple juice that was sterilized at LT had a lower hydroxyl radical scavenging activity level than the other apple juice. Finally, the apple juice that was sterilized at LT showed significantly stronger activities that inhibit enzyme-related oxidation than the apple juice that was sterilized at HT ($p$ <0.05).

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.1
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• pp.6-13
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• 2001

The study was conducted to investigate the effect of the browning inhibitors such as PVPP(polyvinylpoly-pyrrolidone), A.A.(ascorbic acid) on nonezymatic browning factors [free sugar, total amino acid, organic acid, A.A., HMF (hydroxymethylfurfural)] and enzymatic browning factors [PRO (polyphenoloxidase) activity, polyphenol compounds] in concentrated apple juice during 90 days storage. Considering color value (L value, $\Delta$E), absorbance at 420 nm, concentrated apple juice during 90 days storage. Considering color the effect of browning inhibition. According to the storage period, the changes of nonenzymatic factors in concentrated apple juice added with browning inhibitors were similar to those in control (concentrated apple juice without browning inhibitors), which were the decreased of sucrose(0.24~0.35% at 90 days), the slight increase of glucose and fructose, the decrease of total amino acid (530.4~573.1 mg/10g at 90 days), same value of A.A. at 90 days (38.5~78.6 mg/100g), and the increase of HMF (27.8~30.6 mg/100g at 90 days). On the contrary, enzymatic browning factors were significantly inhibited in concentrated apple juice added with PVPP, judging from the slow increase of PRO activity and the significant decrease of initial value in polyphenol compounds (especially chlorogenic acid). These results suggest that PVPP plays an important role as enzymatic browning inhibitor, that is, a scavenger of polyphenol compounds by adsorption in concentrated apple juice.

• The Korean Journal of Food And Nutrition
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• v.32 no.2
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• pp.98-105
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• 2019

In this study, bread was prepared using various amount of 'Fuji' apple juice, and quality and antioxidant properties investigated. Bread was prepared with water, butter, yeast, salt, sugar, wheat flour, skim milk powder and 10, 20 and 30% (w/w) 'Fuji' apple juice. Leavening ability and pH of dough were also investigated. Volume, pH, specific volume, baking-loss rate, chromaticity and texture were investigated as quality properties, whereas the total polyphenol content, ABTS and DPPH radical scavenging activity as the antioxidant properties of bread containing various amount of apple juice. The pH and leavening ability of dough were observed to decrease with increasing amount of apple juice. In the quality properties of bread, pH, volume, specific volume, and baking-loss rate decreased. Regarding chromaticity and texture of bread prepared with increasing amount of 'Fuji' apple juice, L (bright) values at crust and crumb of bread decreased, while hardness, chewiness and gumminess increased. Total polyphenol content increased with increasing amount of apple juice, while DPPH and ABTS radical scavenging activities showed no significant differences. Consequently, these results support the possible use of apple juice for baking foods in food industry, as addition of apple juice enhances the quality and antioxidant properties of bread.

• The Korean Journal of Food And Nutrition
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• v.12 no.4
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• pp.344-349
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• 1999

The mineral contents were analyzed for apple juices by Inductively Coupled Plasma. The Mg contents of tested commercial apple juices ranged 6.27∼32.91ppm, Ca 15,95∼3.11.76ppm K231∼1148.02ppm Na 39.82∼115.68ppm and P 19.27∼304.02ppm. The mineal contents of model apple juice were Mg 29.83∼45.65ppm Ca 16.98∼30.98ppm K 814.28∼1,256.70ppm Na 19.88∼26.85ppm and P 25.88∼54.71ppm. respectively. Comparing mineral contents of model apple juices and commercial apple juice, Na, Ca and P contents of commercial apple juices were higher but Mg, K contents were lower than that of model apple juices. Among the mineral content of apple juices. K was the major element.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.2
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• pp.181-187
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• 2000

The contents of organic acid in Korean apple juice were analyzed by HPLC using YMC-peak ODS-AQ column and enzymatic assay. Model apple juices were prepared at the laboratory and commercial apple juices were purchased from the market. Individual organic acid contents were as follows: DL-malic acid 62~402mg%, L-malic acid 48~360mg%, citric acid 1.81~15.74mg%, fumaric acid nd~0.50mg%. Together, these tests gave useful information about the quality and authenticity of a particular apple juice smaple. The presence of D-malic acid was a clear indication of adulteration because this isomer did not occur naturally. Fumaric acid and citric acid levels above trace amounts were also inconsistent with pure apple juice.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1484-1487
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• 1998

Superoxide dismutase (SOD)-like activities of sixteen kinds of fruits, vegetable juice and commercial concentrates were measured by pyrogallol autoxidation method. The changes in SOD-like activity by heat treatment and the increase in SOD-like activity of apple juice mixed with fruits and vegetables were investigated. SOD-like activity of broccoli juice was 41.7%, the highest value among tested sample. SOD-like activities of strawberry juice, carrot concentrate, kiwi juice, radish juice and apple juice were 30.2, 30.0, 27.6, 26.7, 24.1 and 14.6%, respectively. SOD-like activity was increased generally after heat treatment at $95^{\circ}C$ until 20 min. SOD-like activity of apple juice was increased $20{\sim}35%$ by mixing with 20% of carrot concentrate, kiwi juice, strawberry juice, broccoli juice, respectively and particularly was increased 48% by mixing with 20% of raddish juice.

• Journal of Plant Biotechnology
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• v.48 no.4
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• pp.271-277
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• 2021

The present study aimed to assess and compare the quality characteristics and antioxidant activities of apple juice and blueberry juice at hourly intervals over a period of time based on the presence or absence of vacuum blending (0 and 800 hPa) using a household blender. Measurement of the dissolved oxygen content revealed that the removal rates of dissolved oxygen were approximately 83% and 86% in the apple and blueberry juice samples, respectively, after vacuum blending. Moreover, compared with general blending, there was little change in the antioxidant property and degree of browning over time with vacuum blending. Furthermore, hourly assessments revealed that the decrease in the polyphenol and flavonoid contents in the apple and blueberry juice samples was significantly lesser with vacuum blending for 3, 6, and 12 h than with general blending. Assessment of the change in ferric reducing antioxidant power (FRAP) activity over time revealed that the rate of decrease in FRAP activity over time was lower with vacuum blending than with general blending for both juice samples. ABTS and DPPH radical scavenging assays performed to determine the change in free radical scavenging activity revealed inhibitory activity at 0, 3, 6, and 12 h and confirmed that vacuum blending resulted in long-lasting antioxidant activities in both apple and blueberry juice samples. Taken together, the present results confirmed that vacuum blending is associated with superior quality maintenance and antioxidant properties in comparison with general blending.

• Preventive Nutrition and Food Science
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• v.8 no.3
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• pp.225-229
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• 2003

Clarified apple, carrot and orange juices were prepared using ultrafiltration and their single and blend juices were further concentrated using ultrafiltration, freeze-drying, and rotary evaporation. Effect of concentration methods on the quality of concentrated single juices and juice blends was investigated. Turbidity values of samples concentrated by evaporation were significantly higher than those prepared by ultrafiltration and vacuum freezing regardless of juice source (i.e., apple, orange or carrot) or blending (p<0.05). The highest soluble solids contents were obtained for the samples concentrated by evaporation process. Concentrated apple juice contained significantly higher amount of vitamin C and soluble solids than concentrated orange and carrot juices regardless of concentration methods (p<0.05). For blended samples, no direct relationships between blend ratio and total amount of vitamin C were found; however, samples contained more apple juice showed the highest value of soluble solids regardless of concentration methods.

• 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.