• Clean Technology
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• v.25 no.3
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• pp.223-230
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• 2019

This research was performed to evaluate the characteristics of food waste from 5 areas in Gangwon Province, Korea and to predict the $CH_4$ gas production rate. Food wastes were sampled in July and September, 2017. The amount of methane gas generation was evaluated through the biochemical methane potential (BMP) test and a calculation method using chemical composition. Average bulk density and pH of the food wastes were in the range of $0.758{\sim}0.850g\;cm^{-3}$ and 4.29 ~ 4.75, respectively. By physical composition, vegetables were the highest with 56.43 ~ 72.81% with fruits recording 5.31 ~ 8.95%, cereals 1.60 ~ 18.73%, fish and meat 4.47 ~ 12.11%, and filtrate 1.76 ~ 3.64%. The average water content was 69.30 ~ 75.87%, and VS and ash content were 22.50 ~ 27.98% and 1.63 ~ 2.48%, respectively. In addition, $BOD_5$, $COD_{Cr}$, and $COD_{Mn}$ were in the ranges of $17,690.3{\sim}33,154.9mg\;L^{-1}$, $106,212.3{\sim}128,695.5mg\;L^{-1}$, and $51,266.1{\sim}63,426.3mg\;L^{-1}$, respectively. The NaCl content ranged from 0.81 to 1.17%. The results of elemental analysis showed that the contents of C, H, O, N, and S were 44.87 ~ 48.1%, 7.12 ~ 7.57%, 40.13 ~ 43.78%, 3.22 ~ 4.14%, and 0.00 ~ 0.02%, respectively. In a comparison of the methane production yield per VS mass of food waste, there was no significant difference between the cumulative amount (${0.303{\sim}0.354m_{CH4}}^3\;{kg_{VS}}^{-1}$) by the BMP test and the theoretical amount (${0.294{\sim}0.352m_{CH4}}^3\;{kg_{VS}}^{-1}$) calculated by chemical composition.

• Korean Journal of Food Science and Technology
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• v.45 no.1
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• pp.25-33
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• 2013

Clenbuterol and ractopamine, which are ${\beta}$-agonists, have been misused as a growth promoting agent in meat producing animals. Clenbuterol was banned for veterinary drug in Korea because of its problems regarding safety. Due to their adverse effects, such as cardiovascular and central nervous diseases on human health proper control and monitoring should be conducted. The existing analytical method of clenbuterol and ractopamine in the Food code was improved through our present study. The bovine muscle samples were subjected to enzymatic hydrolysis, extracted with ethyl acetate and defatted by hexane-methanol partitioning. A molecular imprinted polymer (MIP) solid phase extraction cartridge was used for clean-up and LC-MS/MS was operated in positive multiple reaction monitoring (MRM). Clenbuterol-$d_9$ and ractopamine-$d_3$ were used as an internal standard. The renewed method was validated according to the CODEX guideline. The limits of quantitation for clenbuterol and ractopamine were 0.2 and 0.5 ${\mu}g/kg$, respectively. The mean recoveries ranged in 104.2-113.5% for clenbuterol and in 107.6-118.1% for ractopamine. The improved method was able to save both time and expenses.

• Journal of Korean Home Economics Education Association
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• v.35 no.1
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• pp.35-52
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• 2023

This study investigated the utilization and satisfaction of lunchboxes according to food-related lifestyle. A sample of 819 adults who regularly purchased lunchboxes were studied. This study can provide basic data for effective menu development. The participants of the study were classified into 4 groups: a 'taste-seeking group', an 'economy-seeking group', 'a convenience-seeking group', and a 'health-seeking group'. The purchase price of lunchboxes was in the range of 3,500 to 4,000 won. The 'health-seeking group' was shown to spend the highest amount on lunchboxes, over 5,100 won. Information about lunchboxes was obtained primarily through convenience stores followed by Internet SNS (p<0.05). Most participants considered nutritional value when purchasing a lunchbox (p<0.001), of which protein, caloric, and sodium content were perceived as important. Moreover, lunchboxes with clean and hygienic aesthetics were preferred amongst the 'health-seeking group' (p<0.01). The 'economy-seeking group' had a higher satisfaction linked with taste (3.66) and quantity (3.60, p<0.001). Furthermore, in terms of the satisfaction with a menu variety the 'health-seeking group' showed the highest satisfaction with a score of 3.76, while the 'convenience-seeking group' ranked the lowest satisfaction with a score of 3.46 (p<0.05). All groups were satisfied with the convenience for purchasing lunchbox (p<0.001). Additionally, most participants preferred white rice (p<0.001) and meat (p<0.01) with cooked by fried and grilled. Lastly, in the content of the lunchbox use in the future, most participants indicated the intent for continuous use (p<0.01) and recommendation to others with the reason for the low price (19.2%) in the 'economy-seeking group', fresh ingredients (16.2%) in the 'convenience-seeking group', and nutritive (17.3%) in the 'health-seeking group', as well as for the convenience of purchase in the overall groups. Taken together, 'taste' and 'convenience' were the most important factors for all groups, while 'nutrition of food' and 'addition of condiments' scored relatively low on the satisfaction in all groups. Therefore, we recommend for the growth of the convenience store lunchbox market, that it is necessary to improve the quality of the lunchbox by developing various menus based on lifestyle group and fortifying nutrition.