• The Korean Journal of Food And Nutrition
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• v.30 no.3
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• pp.568-577
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• 2017

Vegetables and fruits contain a great deal of vitamins, minerals, dietary fiber and phytochemicals. Therefore, healthconcious consumer prefer beverage made from fresh fruits and vegetables due to their health benefits. This study was conducted to investigate differences in nutritional composition and sensory characteristics of juices depending on the apparatus used: either a low-speed juicer or high-speed blender. All ingredients could be made into juice without addition of water using the low speed juicer. However, addition of water was necessary to produce juice with the high-speed blender. Phenol and flavonoid content, were higher in juice made with the low-speed juicer than that produced with the high-speed blender and were correlated with DPPH radical scavenging ability. Protease activity of pineapples juices was not significantly different for the two methods, but protease activity of kiwi juice was about 8 times higher in juice made with low-speed juicer than that made with the high-speed blender. SOD activity also tended to be higher in the juice made with low-speed juicer. The concentration of dissolved oxygen in the juice made with high-speed blender was higher than that of juice made with a low-speed juicer and was correlated with color change. In addition, the high-speed blender caused an increase juice temperature, but temperature was not changed during use of the low-speed juicer. The noise level of the low-speed juicer was low, but the high-speed blender had high noise intensity comparable to that of railway or aircraft noise. In the sensory evaluation of juice, juice made with the low-speed juicer was preferred over juice made with the high-speed blender. As a result, the overall quality of the juice produced using the low-speed juicer was superior.

• Journal of Food Hygiene and Safety
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• v.15 no.2
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• pp.88-94
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• 2000

The purpose of this presents is to investigate, using natural food extracts(Green tea; Camellia sinesis, Du'chung; Eucommia ulmoides Oliver, Eu sung cho; Houttuynia cordate Thunb, Sam back cho; Saurus Chinensis, Baek hwa sa seal oho; Oldenladia diffusa Roxb., Laver; Porphyra tenera, Sea mustard; Undaria pinnatifda and Sea staghorn; Condium fragile) and juices(Sweet pepper; Capsicum annuum var. angulosum, Kale; Brassia oleracea var. acephala, Cucumber; Cucumis sativus, Onion; Allium cepa, Tomato; Lycopericon esculentum, Maesil; Prunus mume, Plum; Prunus salicina and Grape; Vitis spp.), the effect of natural plant components on the nitrite-scavenging under the different levels of pH. From the above mentioned extracts and juices, the content of vitamin C was detected, containing 65.1∼77.1 mg/100g, at the highest level in the Green tea, and followed by vegetables and fruits in order. The nitrite scavenging effect of teas, medicinal plants, and seaweed extracts, in the reaction system under the condition of pH 1.2, were 57.0∼100%, 50.0∼100%, and 18.0∼99.0%, respectively. Especially, the nitrite was scavenged to the level of 100%1 when 10 ml of kale and 5 ml of maesil Juice

• Journal of the Korea Convergence Society
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• v.12 no.12
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• pp.153-159
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• 2021

The purpose of this study is to determine the demage of tooth surface changes according to exposure time of commercially available green grape juice and pomegranate juice. Extracted healthy human premolar enamel surfaces were used. Control group immersed in phosphate-buffered saline (PBS) and 10 ml of commercially available green grape juice and pomegranate juice applied experimental group was divided into 7 groups. The pH of the experimental juice was measured, and the change and micrographics of the surface were confirmed through a Scanning Electron Microscope (SEM). It was found that the more the immersion time between the tooth surface and acid juice, such as damage to the tooth surface, has a greater effect on the surface damage. Based on the results of this study, it is necessary to reduce the number of drinking times and retention time in the oral cavity.

• The Korean Journal of Food And Nutrition
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• v.28 no.1
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• pp.47-59
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• 2015

In this study, we investigated the dietary habits, snacks, and self-purchasing snacks (SPS) intake behaviors of 519 elementary school students (boys=239, girls=280). Obesity was significantly higher (p<0.05) in boys (24.8%) than in girls (14.7%) and the proportion of underweight subjects was higher compared to normal or other weight groups for both the boys and the girls. There were 7.5% of the subjects in the group that always skipped breakfast, and the main reason of skipping breakfast was insufficient time (51.9%). The snack intake frequency was once or twice per week for 23.1% of the subjects and three or four times per week for 25.1%. The SPS intake frequency was the subjects zero for 35.6% of the highest level of the responders, while 6.8% of the respondents took more than once SPS per day. 59.6% of the respondents consumed SPS due to hunger while 15.0% consumed SPS out of boredom. The SPS was purchased from supermarkets in 34.5% of the cases, from convenience stores in 24.1% and from snack corners in 20.0% of cases or from a store near school in 14.5% of the cases. Analysis of SPS behaviors according to obesity index showed that parent's opinion of 'permission to buy SPS as needed' had a significant effect in 64.5% over weight subjects compared to only 53.7% in underweight groups. The subjects who used more than 3/4 of their pocket money to buy SPS was higher in the overweight groups (16.4%) than in the underweight groups (7.0%) and normal weight groups (9.8%). The favorite snacks and SPS were milk and yogurt for 45.7% of the subjects, fruits for 42.7%, ice cream for 26.4%, fruit juices for 23.8%, sweet stuff for 16.4%, frozen dessert for 8.9%, and chocolate or candy for 8.1% in descending order. The intake frequency of milk, yogurt, and fruit juices was higher in the underweight groups, but the intake frequency of sweet stuff, frozen dessert, and chocolate or candy was higher in over weight groups. The intake of frozen dessert was more than four times higher in the overweight groups than in the underweight groups. In conclusion, dietary habits, snacks, and SPS intake behaviors were similar between the boys and the girls and obesity groups, but most students appeared to have a high preference for intake snacks and SPS. Therefore, education for appropriate snacks intake habits will be beneficial for improving their dietary habits and health.

• Korean Journal of Food Science and Technology
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• v.30 no.1
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• pp.90-96
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• 1998

An experiment to make mixed juices carrying the freshness and other specific characteristics of vegetables and fruits which are useful for the prevention and treatment of various diseases was attempted on the emphases of pretreatment methods, combination of fruits and vegetables, and elimination of microorganisms. Blanch in boiling water prior to extraction for green vegetables, addition of ascorbic acid during extraction for tomatoes and apples, or addition of ascorbic acid after blanch in 3% acetic acid for carrots was effective to keep colors and suspended solids in liquid extract. On the basis of sensory evaluation the extracts from tomatoes, apples. carrots. mallows, watercreses+pine needles, Angelica keiskei Koiz, jujubes and lemons were selected and mixed at the ratio of 3 : 3 : 3 : 1/2 : 1/2 : 1/2 : 1/2 : 1/5. The mixed extracts were pasteurized for 15sec at $96^{\circ}C$ or filtered through a ultramembrane filter. While the centrifuge precipitation and retentates on the membrane filter were autoclaved and combined with ultrafiltrates. The mixed juices showed $pH\;4.07{\sim}4.10$ titratable acidity $66.35{\sim}84.08$, soluble solid $7{\sim}9^0Brix$, reducing sugar $5.42{\sim}6.97%$, glucose $1.96{\sim}2.30%$, fructose $3.46{\sim}4.14%$ and high content of K, Mg and Ca. Ultrafiltration showed better quality scores in color, juice. Peroxidase and microorganisms were inactivated by thermal treatment and ultrafiltration.

• Korean Journal of Food Science and Technology
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• v.29 no.6
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• pp.1241-1247
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• 1997

Gel-type fermented milk was prepared from milk or mixture of milk and apple juice/grape juice. Acid production (pH change) and growth of Lactobacillus acidophilus (KCTC 2182) were studied. The effects of juice addition on sensory property of fermented milk were also studied. The pH value of samples containing mixture of milk and apple juice/grape juice (25 mL : 25 mL to 5 mL : 45 mL) was lower than that of milk sample. However, number of viable cells of L. acidophilus at 21 hr in milk and samples containing juices was similar. During lactic fermentation for 24 hr, pH of all samples dropped significantly between 6 hr and 21 hr. pH values of mixture of milk and juices were lower than that of milk sample. Growth curve showed that lag phase continued to approximately 3 hr and log phase continued to approximately 15 hr in all samples. Number of viable cells in all samples was similar Sensory evaluation showed that overall acceptability of fermented milk prepared from apple juice/grape juice and milk (15 mL : 35 mL or 5 mL : 45 mL) was better than that of reference sample. The optimum ratio of mixture of juice and milk was 15 mL : 35 mL. The score values of sensory test of fermented milk prepared from mixture of grape juice and milk were slightly higher than those of mixture of apple juice and milk.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.1
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• pp.80-91
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• 2014

The aim of this study was to establish the superiority of ohmic heating over conventional heating for the sterilization of mulberry juice. Heat treatment of fresh juice significantly reduced the concentration of soluble solids, lowered the pH, and lowered the reducing sugar content (p<0.01). Color measurements showed decreases in the L and a values and increases in the b, H and C values after heat treatment, although the total color differences were smaller after ohmic heating than after conventional heating of fresh juice. The antioxidant capacities, such as reducing power, FRAP, and DPPH, decreased in the order of fresh juice, ohmically heated juice and conventionally heated juice. Furthermore, the anthocyanin, flovonoid, and total antioxidant capacities of the juices significantly decreased in the same order. Sensory evaluations showed no difference between fresh and ohmically heated mulberry fruit juice excluding off-flavor, whereas conventionally heated juice received significantly lower evaluations. The microbial counts were zero in the juice after either heat treatment. Thus, ohmic heat treatment can be effectively used to sterilize fresh mulberry juice to obtain good shelf life with minimal physicochemical, color, antioxidant and sensory deterioration.

• Journal of Nutrition and Health
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• v.24 no.5
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• pp.469-476
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• 1991

This study was conducted to investigate the weaning practice of 170 infants, aged 6 to 20 months, in Sockcho city Kangwon province. Informations on the infant feeding were obtained by interviewing mothers in three different pediatric clinics located in Sockcho. In this survey 40.4% of infants were breast-fed, while 44.1% of them were bottle-fed. Among subjects 75.9% of infants began to be weaned within 6 months. Among those who finished weaning aleady, 56.7% of infants fnished weaning 11 to 13 months. Sixty percent of mothers got the nutritional knowledge on infant feeding by the aid of cook book and child care book. Fruit juice was firstly introduced as infant food. The most favorite food for infants was fruit juices which were followed by soup, and e99 Pudding. Cereals were used frequently as infant foods while meat & fish, beans and vegetables were lesser used for infants. For the improvement of nutritional states of infants. nutritional education programmes and development of infant food is needed.

• Journal of the East Asian Society of Dietary Life
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• v.25 no.3
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• pp.405-416
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• 2015

This study aimed to compare the dietary habits, nutritional knowledge, and health-related behaviors of students by high school type using questionnaires. The subjects were 586 male students (academic high school students (AS); 294, specialized high school students (SS); 292) in Jinju, Gyeongnam. The frequencies of eating breakfast and snacks were higher in AS than in SS (p<0.05), whereas the frequency of drinking was higher in SS than in AS (p<0.05). The main reason for skipping breakfast was 'poor appetite' in AS (45.2%) and 'lack of time' in SS (56.5%) (p<0.05). Favorite snacks included 'pizza, hamburger' (33.0%) and 'bread, noddle, ramyun' (31.0%) in AS as well as 'pizza, hamburger' (32.5%) and 'fruit, fruit juice' (26.0%) in SS. A mean of 56.2% of students ate an unbalanced diet, and the main reason was 'untasty' (47.2%). The frequency of eating out was higher in SS than in AS (p<0.05), and the main menu while eating out was 'Korean food' in AS (96.3%) and SS (90.3%). The frequency of 'meat, fish, egg, beans' was higher in AS than in SS (p<0.05). On the other hand, the frequencies of 'fruit, fruit juices' (p<0.05), 'milk, milk products' (p<0.01), 'seaweeds' (p<0.05), 'instant foods' (p<0.001) and 'soda and ion drinks' (p<0.001) were higher in SS than in AS. The mean rates of drinking and smoking in students were 84% and 29.5%, respectively. The main reason for drinking and smoking was 'to relieve stress' in AS (38.0%) and SS (30.9%) (p< 0.001). In general, the nutritional knowledge level of SS was higher than that of AS. In conclusion, there were significant differences in the frequencies of eating breakfast, food intake, drinking and reasons for eating snacks, unbalanced diet, drinking and smoking between AS and SS. Therefore, it's necessary to provide proper nutritional education for students according to high school type.

• Food Science and Biotechnology
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• v.16 no.5
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• pp.740-746
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• 2007

Fruit juices such as grape juice are associated with healthy products by consumers because of the many health benefits they provide. Farm produced (FPGJ) and commercially produced grape juice (CPGJ) in South Korea were compared and studied through the evaluation of their physicochemical, functional, and sensory properties. The results of this study show that FPGJ's physicochemical properties are more varied than CPGJ. The pH, titratable acidity, and total soluble solids of FPGJ were higher than CPGJ. FPGJ had a higher mean value for total phenolics ($2,558.20{\pm}50.06\;mg/L$ GAE), total flavonoid ($3,236.80{\pm}56.11\;mg/L$), total anthocyanin ($559.88{\pm}3.51\;mg/L$), and radical scavenging activity (86.48%) than CPGJ, although the differences were significant only with regard to total flavonoid and total anthocyanin. This study also demonstrates that CPGJ is preferred in terms of sensory evaluation. These properties may be used as a basis for the optimization of processing to produce a higher quality grape juice.