• Korean Journal of Environmental Agriculture
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• v.36 no.3
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• pp.184-192
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• 2017

BACKGROUND: This study was performed to evaluate the residue dissipation of boscalid and spinetoram on crown daisy and sweet pepper affected by the morphology of the crop. The half-lives and dissipation rate constants for boscalid and spinetoram on crown daisy and sweet pepper were calculated. And then lower limit of 95% confidence interval for dissipation rate constant could be used to propose the pre-harvest residue limit. METHODS AND RESULTS: The pesticide products diluted according to the pesticide label were applied one time on crown daisy and sweet pepper at 2 field sites, respectively. Initial concentration of boscalid and spinetoram on crown daisy after application were in the range of 72.80~117.15 mg/kg and 2.82~4.67 mg/kg, respectively. And Initial concentration of boscalid and spinetoram on sweet pepper were in the range of 1.58~1.62 mg/kg and 0.10~0.21 mg/kg, respectively. Boscalid and spinetoram for crown daisy dissipted below the maximum residue limit(MRL) at 10 and 2 days after application, respectively. All residues concentration of boscalid and spinetoram for sweet pepper below the MRL at 0 day after application. The half-lives based on dissipation rate constant for boscalid and spinetoram on crown daisy were 4.2~4.9 days and 3.0~2.4 days respectively. And the half-lives for boscalid and spinetoram on sweet pepper were 6.7~7.0 days and 2.8~4.0 days respectively. CONCLUSION: The difference in initial concentration of boscalid and spinetoram among crop commodities were due to different crop morphology with larger surface areas. This study was suggested that pre-harvest residue limit would be calculated from lower limit of 95% confidence interval for dissipation rate constant and would be useful to protect consumers by controlling the pesticide residues in crop.

• The Korean Journal of Food And Nutrition
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• v.26 no.3
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• pp.508-514
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• 2013

This study was conducted to evaluate the effect of various types of functional brown rice milk porridge, which has been popular as a fast yet nutritional food, to promote rice consumption and to examine the best ratio and recipe. Each sample contained 10, 20, 30, and 40% brown rice compared to non-glutinous rice and sweet rice and were applied to mechanical and sensory tests. The moisture content of both non-glutinous rice and sweet rice porridges increased with increasing brown rice content. The viscosity of non-glutinous rice milk porridge decreased as with increasing brown rice content, whereas the viscosity of sweet rice milk porridge increased with increasing brown rice content. The pH was highest for BRT0 at 6.74 and lowest for BGT0, which is sweet rice porridge with brown rice, at 6.27. The sweetness decreased significantly for both sweet rice and non-glutinous rice porridges with the increase in brown rice content. The brightness of weet rice and non-glutinous rice porridges with brown rice increased significantly (p<0.001) with the increase in brown rice content, while the redness and yellowness of the color increased significantly (p<0.001) with increasing in brown rice content. As a result of analyzing the preference in the milk porridge containing brown rice, BRT30, which is non-glutinous rice milk porridge with brown rice, was most preferred at 5.8 in terms of color, while BRT30 was most preferred at 6.2 in terms of fragrance. All samples containing brown rice powder were highly preferred in terms of taste and the overall preference of sweet rice milk porridge was highest for BRT30 (5.8). The overall preference was highest for BGT30 at 6.1 and the preference was generally higher for the experiment groups prepared with sweet rice as opposed to those prepared with non-glutinous rice. Also, the scores for the sensory test were higher when brown rice was added. Therefore, it was concluded that the milk porridge could quickly and easily be prepared with brown rice instead of non-glutinous rice or sweet rice.

• Korean Journal of Food Science and Technology
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• v.27 no.5
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• pp.819-825
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• 1995

Two sweet potato CV.(Ipomoea batatas) were examined, i.e. purple flesh sweet potato(PSP) and light yellow flesh sweet potato(LYSP) which varied in degree of sweetness. On a fresh weight basis, nitrogen free extract in cultivars ranged from $25.73{\sim}26.24%$ and PSP contained more crude fat than LYSP. Total amino acids of PSP and LYSP were 5676.57mg% and 4550.86mg%, respectively. Aspartic acid, serine, alanine and valine were the major components in sweet potatoes. Sulfur-containing amino acids are the first limiting amino acid in PSP. The major fatty acids in PSP and LYSP analyzed by GC were palmitic acid, linoleic acid. The content of the saturated fatty acid was less than that of the unsaturated fatty acid. Carbohydrate contents were $75.43{\sim}79.10%$ and neutral sugars contents were $67.22{\sim}64.85%$(dry wt). Two sweet potato CV. contained the most glucose of all neutral sugars. PSP contained 11.88% for uronic acid, 59.42% for starch. Free sugars of PSP(0.82%) was much less than that of LYSP(2.53%). The contents of thiamin, riboflavin and niacin were similar, and the ascorbic acid contents in PSP and LYSP were 63.4mg% and 48.7mg%(dry wt), respectively. Comparing the mineral content in PSP, K was the greatest element in concentration followed by mg, Ca, Na. The total dietary fiber(TDF) value was 13.43% in PSP, 9.79% in LYSP respectively. The ratio of soluble dietary fiber(SDF) content and insoluble dietary fiber(IDF) content to TDF content for PSP were 57.6%, 42.4%, respectively.

• Food Science and Preservation
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• v.15 no.6
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• pp.832-839
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• 2008

The stock that is the first step for preparation of soups and purees links to the taste of food. Many types of vegetable have been used in stocks, but this study focused on stocks prepared with sweet pumpkin. The stock preparation conditions including the weight of sweet pumpkin, the water volume, and the boiling time at $97^{\circ}C$ were optimized by response surface methodology. The quality characteristics of the resulting stock were investigated. The color, flavor, taste and overall acceptability were dependent parameters. A model equation was proposed with regard to the sweet pumpkin weight, water volume, and boiling time at $97^{\circ}C$. A sweet pumpkin weight of 357.9 to 403.0 g, a water volume of 689.8 to 768.5 mL, and a boiling time of 9.9 to 10.3 min at $97^{\circ}C$ were found to be the optimal stock preparation conditions. The quality characteristics of the sweet pumpkin stock prepared under the optimized conditions were pH 6.64, total acidity 0.18%, soluble solids $2.39\;^{\circ}Brix$, color value (L, 99.07 a, -2.43 b, 11.82), total polyphenol 280.75 mg/L, and electron donating ability 21.32%.

• Food Science and Preservation
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• v.18 no.5
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• pp.706-713
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• 2011

This study was conducted to investigate the chemical characteristics of Gochujang with different amounts of sweet persimmon powder added during fermentation at $20^{\circ}C$ for 90 days, in an effort to improve its taste and organoleptic quality. The moisture content was shown to be inclined to increase in all the treatments throughout the fermentation. There was no significant difference between the paste with sweet persimmon powder and the control. The pH showed a tendency to decrease with increased fermentation time in all the samples during fermentation, keeping a pH range of 4.64-4.67 after 60 days of fermentation. On the contrary, the titratable acidity increased during fermentation, showing a level of 0.147-0.156 mg% in the paste with sweet persimmon powder on the 90th day of fermentation. The sugar content was shown to be $33.67-39.67^{\circ}Brix$ in the early stage of fermentation, revealing a tendency to in crease with an increase in the amount of sweet persimmon powder added. The amino-type nitrogen content was at the 241.27-245.47 mg% level in the early stage of fermentation, and appeared to be significantly high (p<0.05) in the treatments with 3 and 4% sweet persimmon powder added, respectively, after 60 days of fermentation. The content was within the range of 357.47-371.53 mg% on the 90 th day of fermentation in the final stage, showing an increase trend throughout the fermentation. The alcohol content gradually increased with an increase in fermentation time, showing a range of 0.94-0.10% on the 90th day of the final stage of fermentation. Moreover, the content was highest (0.96-0.108%) on the 70th day of fermentation, demonstrating a trend to slightly decline in all the treatments thereafter.

• Applied Biological Chemistry
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• v.30 no.4
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• pp.315-322
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• 1987

Attempts were made to unravel the differences in the textural properties between a dry type, Wonki and a moist type, Chunmi sweet potato. The changes in the ingredients, cellular shapes, degree of gelatinization and hardness of sweet potatoes during baking were studied. Alcohol insoluble solid, starch and protopectin contents and activities of amylase and polygalacturonase of Wonki sweet potato were higher than those of Chunmi sweet potato. The cell sizes were smaller and the number of starch granules within the cells were higher in Wonki than in Chunmi. Gelatinization occurred in Wonki more lately than in Chunmi during baking. The difference in hardness after baking between Wonki and Chunmi was found distinctively. But both samples were gelatinized completely, the difference in hardness was not found.

• Journal of Food Hygiene and Safety
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• v.10 no.4
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• pp.263-270
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• 1995

In order to promote the prevention of microbial and enzymatic spoilage and to retain the freshiness, sweet persimmons harvested in Gyeongsangnam-do were treated with graperfruit seed extract(GFSE)-CaCO3 mixture and stored in the proper packaging conditions. A low concentration of GFSE showed effective growth inhibition of plant pathological bacteria and fungi, Enterobacter pyrinus and Fusarium sp., which were involved in the decay of fruits and vegetables. GFSE was stable to heat treatment; its antimicrobial activity was not changed by heat treatment upto 10$0^{\circ}C$. However, when the temperature was raised to 12$0^{\circ}C$, about 90% of total activity was retained within 30 min. GFSE was also highly stable to broad pH changes; its activity was not changed in the range of pH 2.0 to pH 12.0. The physiological function of cell membrane in the spores of Bacillus cereus and the hyphae of Fusarium sp. was destroyed by treating with GFSE. It was observed that treating sweet persimmons with GFSE minxture and storing them in strech-wrapped packages could prolong the greshness of sweet persimmons and reduce quality deterioration.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.5
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• pp.790-795
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• 2000

To establish the optimum conditions for the extraction of anthocyanin pigment from purple-fleshed sweet potato, a suitable extraction solvent with the optimum citric acid concentration for acidification of the solvent, and the optimum extraction time and temperature were determined. Twenty percent ethanol solution acidified with citric acid was found to be a good solvent for the extraction of the pigment from purple-fleshed sweet potato. About 10 hour extraction at room temperature was appropriate for the extraction. pH of the extract was below 3 when more than 0.7% citric acid was added. The higher the concentration of citric acid added was, the higher the total optical density (TOD) of the extract was. However, the increase in TOD of the extract was insignificant when more than 1% of citric acid was added. Therefore, addition of 1% citric acid was determined for acidification of the extracting solvent. Though the initial rate of the pigment extraction increased as the extracting temperature increased, extraction at higher temperatures of 60 or 8$0^{\circ}C$ for an extended time caused a decrease in the extraction yield due to degradation of the pigment. The optimum extraction temperature for the anthocyanin pigment from purple-fleshed sweet potato with the solvent used was determined as 4$0^{\circ}C$.

• The Plant Pathology Journal
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• v.30 no.4
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• pp.416-424
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• 2014

Sweet potato is grown extensively from tropical to temperate regions and is an important food crop worldwide. In this study, we established detection methods for 17 major sweet potato viruses using single and multiplex RT-PCR assays. To investigate the current incidence of viral diseases, we collected 154 samples of various sweet potato cultivars showing virus-like symptoms from 40 fields in 10 Korean regions, and analyzed them by RT-PCR using specific primers for each of the 17 viruses. Of the 17 possible viruses, we detected eight in our samples. Sweet potato feathery mottle virus (SPFMV) and sweet potato virus C (SPVC) were most commonly detected, infecting approximately 87% and 85% of samples, respectively. Furthermore, Sweet potato symptomless virus 1 (SPSMV-1), Sweet potato virus G (SPVG), Sweet potato leaf curl virus (SPLCV), Sweet potato virus 2 ( SPV2), Sweet potato chlorotic fleck virus (SPCFV), and Sweet potato latent virus (SPLV) were detected in 67%, 58%, 47%, 41%, 31%, and 20% of samples, respectively. This study presents the first documented occurrence of four viruses (SPVC, SPV2, SPCFV, and SPSMV-1) in Korea. Based on the results of our survey, we developed multiplex RT-PCR assays for simple and simultaneous detection of the eight sweet potato viruses we recorded.

• Journal of the Korean Dietetic Association
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• v.16 no.2
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• pp.100-115
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• 2010

This study was performed to investigate the effects of taste preference on dietary behavior and nutrient intake. The subjects were 191 female collegians in the Gyeonggi and Gangwon areas. Data were collected using anthropometric measurements, 24-hour recall, and self-administered questionnaires. The respondents were classified into sub-groups according to taste preference: sweet taste (liked and disliked group), salty taste (liked and disliked group), sour taste (liked and disliked group), hot taste (liked and disliked group), and bitter taste (liked and disliked group). The results of this study are as follows: subjects liked, in order of taste preference, hot>sweet>sour>salty>bitter tastes. There were no significant differences in height, weight, and BMI among the groups. The sweet-taste-liked group, tended to prefer Chinese food and fast foods for eating out over the sweet-taste-disliked group (p<0.05). Subjects in the salty-taste-liked group ate faster (p<0.05) and more than those in the salty-taste-disliked group (p<0.05). They also consumed more animal fat and meat (p<0.05) than their counterparts. Compared with the sour-taste-disliked group, subjects in the sour-taste-liked group tended to select Korean food or Japanese-style food for eating out, and fruits for a snack (p<0.05). The meal size of the hot-taste-liked group tended to be more regular (p<0.05) than that in the hottaste-disliked group. Overall, there were distinct differences in dietary behavior and food choices according to taste preference. Taste preference should be considered for dietary consulting and nutritional education.