• Korean journal of food and cookery science
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• v.31 no.2
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• pp.185-192
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• 2015

This research tried to contribute to the diversification and the high quality of tofu products by adding the natural colors from tomatoes and strawberries, thus providing more attractive colors, greater antioxidative activity, and higher palatability The quality characteristics of tofu with 4%, 8%, and 12% strawberry juice and 5%, 10%, and 15% of tomato juice were analyzed. Tofu with tomato juice was found to be higher in transference number, and pH showed a significant decrease as the rate of the addition increased, The antioxidant activity of tofu with strawberry juice is 37.76~52.12%, and tofu with tomato juice is 41.79~51.51%, with tofu with tomato juice is being higher than tofu with strawberry juice in antioxidant status DPPH radical scavenging ability. In chromaticity, the L-value and b-value showed significant decreases as tomato juice was added and when strawberry juice are was added and the values increased. In texture, the hardness of tofu with tomato juice was found to be significantly more solid than tofu with strawberry juice. For the test of springiness, the order was as follows: control group> tomato juice 5%> tomato juice 10%. The result of the organoleptic test of tofu showed, tofu with tomato juice to be significantly brighter in exterior color than tofu with strawberry juice (p<0.001), in for savory flavor, the result shows that tofu with 12% strawberry juice added and that with 10% tomato juice added had better flavor. For the test of beany flavor, the control group is higher than tofu with strawberry juice and tomato juice, and tofu with 10% of tomato juice added was lowest in beany flavor. In the preference investigation, tofu with 10% tomato juice showed the highest preference after swallowing and in overall status.

• Journal of Environmental Health Sciences
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• v.31 no.1
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• pp.23-30
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• 2005

Staphylococcus aureus is one of the important pathogenic agents, which are related to the hygienic condition. This study performed for the detection of Staphylococcus aureus and screening staphylococcal enterotoxin a, b, c genes in strains isolated from the environment for production of non-pasteurized strawberry juice. A total of 44 samples were collected from utensils, machinery, employees, raw materials, and strawberry juices in 3 strawberry juice shops in Jinju, western Gyeongnam. The isolation rate of Staphylococcus aureus was 26%. Specially Staphylococcus aureus was frequently isolated from employee's hands, strawberry and strawberry juices. The sea, seb, and sec genes were also investigated by polymerase chain reaction (PCR). One hundred and 55% of each isolate had found sea gene and seb gene, respectively. However, sec gene was not detected anywhere. To prevent food-borne disease associated with juice, the accomplishment of HACCP to be more efficient and systematic is necessary.

• Food Science and Preservation
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• v.17 no.1
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• pp.72-78
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• 2010

To develop a low-ethanol strawberry wine, the use of pectinase to improve the extraction yield of strawberry juice was investigated, and changes in physicochemical characteristics during ethanolic fermentation were assessed. The juice yield from strawberry fruit increased by 18.9% after Viscozyme L treatment (1,000 ppm, 30 min), compared with a control group, a greater increase than seen with other pectinases (17.5-18.7%). No significant quality differences were observed between control juice and juice prepared with enzyme treatment, indicating that neither physicochemical characteristics nor ethanol content during fermentation were affected by pectinase treatment. The major pigments of strawberry juice were cyanidin-3-glucoside and pelargonidin-3-glucoside, both of which are anthocyanins. The pigment level after enzyme treatment was slightly lower than that of the control group, at all fermentation times. We consider that the economics of strawberry wine manufacture may be increased by use of pectinase because juice level was increased, but no change in ethanol content or physicochemical characteristics was apparent.

• Korean Journal of Food Science and Technology
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• v.47 no.4
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• pp.480-485
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• 2015

Effects of dynamic high-pressure (DHP) treatments on microbial stability, vitamin C concentration, color, sugar content, color, and pH of strawberry juice were studied and compared with those of the conventional thermal treatment. Freshly prepared strawberry juice was thermally treated at $110^{\circ}C$ for 1 min or treated by DHP at 205 MPa and 20, 50, 60, or $70^{\circ}C$. The thermal treatment and the DHP treatments, both with and without integration with heating at $70^{\circ}C$, reduced the number of indigenous aerobic microorganisms by >6 log CFU/mL. Vitamin C concentration, color, and sugar content were higher in the DHP-treated juice than in the thermally treated juice, regardless of integration with heating. Compared to the thermal treatment, DHP treatments resulted in longer color retention and higher sugar contents in strawberry juice stored at $4^{\circ}C$ for 63 days. These results have demonstrated the potential use of DHP as a novel method for pasteurizing strawberry juice.

• Journal of Life Science
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• v.17 no.12
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• pp.1734-1738
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• 2007

The biological activities of strawberry were investigated during frozen storage. The concentrations of total phenolic content in strawberry juice and water extract were $2.342{\mu}g/ml\;and\;2.235{\mu}g/ml$, respectively. The total flavonoid content in strawberry juice and water extract were $200.36{\mu}g/ml\;and\;201.07 {\mu}g/ml$. respectively. Antioxidant activities of strawberry juice and water extract were determined. The DPPH of strawberry juice (94.2%) was higher than the water extract of strawberry (93.5%). ABTS of strawberry juice and water extract were 99.9% and 100.0%, respectively. Xanthine oxidase inhibitory activity and SOD-like activity of strawberry of water extracts were higher than those of strawberry juice. The changes in the antioxidant activity of strawberry was insignificant until 6 months of frozen storage. Therefore, it was expected that frozen storage of strawberry was useful preservation expedient for consistent supply of raw materials.

• Korean Journal of Soil Science and Fertilizer
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• v.19 no.1
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• pp.9-13
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• 1986

An experiment on strawberry (Fragaria Grandflora EHRH) was conducted in order to compare the effect of two compound fertilizers made for this crop, by Kyonggi Chemical Crop. LTD. with that of muriate of potash, sulfate of potash and ammonium nitrate in a farmer's vinylhouse during the winter period of 1984 to 1985. Results obtained are as follows; 1. The effect of compound fertilizers on the growth, number of inflorescences and yield of strawberry showed no significant difference from the effect of muriate of potash, sulfate of potash and ammonium nitrate. But the former increased the content of reduced, and total sugars soluble in diluted acid in the juice of strawberry. 2. As a whole, sulfate of potash increased sugar content in strawberry juice more than muriate of potash, which became the reason to increase the sugar content in the strawberry juice harvested from the compound fertilizer plots.

• Korean Journal of Food Science and Technology
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• v.49 no.2
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• pp.181-185
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• 2017

Senior-friendly strawberry jelly was developed using strawberry juice, sugar, xanthan gum, and locust bean gum. The experimental variables included strawberry juice (30.0-40.0%, w/w) and sugar (7.5-10.0%, w/w) concentrations and the xanthan gum/locust bean gum ratio (0.3-4.0), and interactions among these variables were predicted using a response surface methodology. The optimal concentrations of strawberry juice and sugar and the ratio of xanthan gum/locust bean gum, determined against jelly hardness, were found to be 40.0, 10.0, and 1.5%, respectively. The hardness, gumminess, and chewiness of strawberry jelly increased significantly during storage at 5 and $15^{\circ}C$ (p<0.05). The lightness of the gum decreased significantly at both temperatures (p<0.05), whereas the hue angle increased during storage at $15^{\circ}C$. The zero-order kinetics was used to predict the shelf-life of the prepared jelly ($R^2=0.89-0.96$), which was determined to be 38 and 26 days at 5 and $15^{\circ}C$, respectively.

• Korean Journal Plant Pathology
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• v.14 no.5
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• pp.445-451
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• 1998

A severe Phytophthora rot of strawberry caused by a species of Phytophthora has been widely occurred at major cultivation areas of Kimhae on August in 1997. Incidence of the disease was obtained in the range of 69.2~83.6% in surveyed 4 fields and showed an average of 75.2%. A species of Phytophthora was mostly isolated from the crown of infected strawberry plants and all the isolates were identified as P. nicotianae var. nicotianae (=P. parasitica). The fungus showed strong pathogenicity on strawberry by inoculation test. As a result of the leaf inoculation using mycelial disks of the fungus, both leaves and petioles were darkly browned, and were finally blighted. As a result of the root inoculation of zoospore suspension, both roots and crowns were rotten with dark brown. Although the fungus produced sporangia either on V-8 juice agar medium or liquid medium, the sporangia observed on the liquid medium appeared to be broadly turbinate and noncaducous. Moreover the fungus cultured on the liquid medium often produced sporangia having two papilla. The number of zoospores in sporangia was found to be ranged from 3 or 4 to as many as 20 or 25. In addition, the released zoospore from the sporangium became the cystospore during the prolonged culture of the fungus. The sporangia were measured as av. 49$\times$35 ${\mu}{\textrm}{m}$ with l/b ratio of 1.43. All isolates from crowns were heterothallic and A1 mating type since oospores were abundantly formed on clarified V-8 juice agar by dual culture with P. capsici A2 mating type. Aplerotic oospores were sized 24-26 ${\mu}{\textrm}{m}$. Antheridia were always amphigynous and recoreded an average of 12$\times$10 ${\mu}{\textrm}{m}$. Hyphal swlling were easily observed, and terminal or intercalary chlamydospores were abundantly formed on V-8 juice agar as well as in C/Z solution and sized av. 28.2 ${\mu}{\textrm}{m}$. This is the first report of Phytophthora rot of strawberry in Korea.

• 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 environmental and Sanitary engineering
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• v.19 no.3 s.53
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• pp.22-30
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• 2004

The extract with the dilution of $50\%$ ethanol and treatment of $121^{\circ}C$ for 15min were inhibited highly the growth of staph aureus, Ent. cloacae, Sh. sonnei, A. hydrophila, b. subtilis, St. faecalis and L. casei. of food samples, red-bean dregs with addition of extact of smilax china. leaves or sorbic acid took the similar inhibition effect to microorganisms for the early storage days(1-3days). There was inhibited the growth of microorganisms in strawberry Juice added to 20m1 of $1\%$ extract solution for one storage day in comparison with no addition of smilax china L. Over all with growth inhibition capability to microorganisms and foods, it was believed that the effect and value as the natural food preservatives and the extracts like as this natural plant material took the food safety and it was capable to develop the natural food preservation.