• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.10
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• pp.1550-1557
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• 2015

This study was conducted to evaluate the improvement effects of bitter taste of doraji (Platycodon grandiflorum) with different freezing temperature conditions ($-5^{\circ}C$, $-10^{\circ}C$, $-20^{\circ}C$, and $-70^{\circ}C$). After freezing for 4 h, frozen doraji was thawed and dehydrated. Doraji frozen at $-20^{\circ}C$ showed higher contents of crude fat, crude protein, crude ash, crude fiber, and nitrogen free extract. Moisture, crude saponin, and total polyphenol contents of doraji frozen at $-5^{\circ}C$ were higher than in other samples. Weight loss of doraji was significantly different as freezing temperature decreased and the process repeated. Doraji frozen at $-5^{\circ}C$ showed higher contents of saponin and phenol than the control. Hardness of doraji increased as freezing temperature decreased. According to the preference test, Doraji frozen at $-5^{\circ}C$ showed higher preference and less bitter taste intensity than other samples. These results mean that doraji frozen at $-5^{\circ}C$ with less bitter taste could be utilized widely as a food material.

• Journal of Dairy Science and Biotechnology
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• v.33 no.2
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• pp.119-127
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• 2015

To date, detection of microbial populations in dairy products has been performed using culture media, which is a time-consuming and laborious method. The recently developed chromogenic media could be more rapid and specific than classical culture media. However, the newly developed molecular-based technology can detect microbial populations with greater rapidity and sensitivity than the classical method involving culture media and chromogenic media. This molecular-based technology could provide various options for monitoring the characterization of different states of bacteria and cells. Thus, it could help upgrade the processing system of the dairy industry so as to maintain the safety and quality of dairy foods. Among the various newly developed molecular-based technologies, flow cytometry can potentially be used for monitoring microbiological populations in the dairy industry if official international standards are available for this purpose. When omics technology would have biomarker identification, it could be regarded as the rapid and sensitive analytical methods. Methods based on PCR, which has become a basic technique in microbiological research, can be developed and validated as alternative methods for quantification of dairy microorganisms. This review discusses methods for monitoring microbiological populations in dairy foods and the limitations of these studies, as well as the need for further research on such methods in the dairy industry.

• Food Science and Preservation
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• v.11 no.2
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• pp.195-200
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• 2004

Microbial lethal value and nutrient retention of sous vide processed spinach were evaluated with mathematical model prediction and experimental trial for different package sizes and pasteurization temperatures. The package size covers 500 g, 1 kg and 2 kg, while the pasteurization temperature includes 80, 90 and 97$^{\circ}C$. The basic process scheme consists of filling blanched spinach into barrier plastic film pouch, sealing under vacuum, pasteurization in hot water with over pressure and final cooling to 3$^{\circ}C$. Pasteurization condition was designed based on attainment of 6 decimal inactivation of Listeria monocytogenes at geometric center of the pouch package by heating cycle, which was determined by general method. Heat penetration property of the package and thermal destruction kinetics were combined to estimate the retention of ascorbic acid and chlorophyll. Smaller packages with shorter pasteurization time gave better nutrient retention, physical and chemical qualities. Larger package size was estimated and confirmed experimentally to give higher pasteurization value at center, lower ascorbic acid and chlorophyll contents caused by longer heat process time. Lower pasteurization temperature with longer process time was predicted to give lower pasteurization value at center and lower ascorbic acid, while chlorophyll content was affected little by the temperature. Experimental trial showed better retention of ascorbic acid and chlorophyll for smaller package and higher pasteurization temperature with shorter heating time. The beneficial effect of smaller package and higher pasteurization temperature was also observed in texture, color retention and drip production.

• Food Science and Preservation
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• v.24 no.3
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• pp.464-471
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• 2017

The purpose of this study was to evaluate the effect of superheated steam drying on physicochemical and microbial characteristics of Korean traditional actinidia (Actinidia arguta) leaves. Actinidia leaves were dried at steam temperature of $350^{\circ}C$ and oven temperature of $150^{\circ}C$ for 40-200 sec. Moisture content and water activity decreased with increasing the drying time, while color values including L, a, and b values and total color difference (${\Delta}E$) increased as drying time increased. The relationship between moisture content and water activity showed an exponential fit with high correlation vlaue ($R^2=0.9909$). Total phenolics and flavonoids content and antioxidant activity such as DPPH radical scavenging activity, ABTS radical scavenging activity, and FRAP assay of dried actinidia leaves increased with increasing the drying time up to 160 sec, but dramatically decreased at drying of 200 sec. The numbers of total areobic bacteria of leaves was not detected at drying time over 120 sec and coliform of all the samples was not detected. As a results, the superheated steam was an very effective drying method of increase to the nutritional and sanitary quality of dried Korean traditional actinidia leaves.

• Journal of Food Hygiene and Safety
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• v.34 no.3
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• pp.242-250
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• 2019

An analytical method was developed for the determination of fenquinotrione, a triketone herbicide, in agricultural products. Fenquinotrione was metabolized to KIH-3653-M-2 in plants. Analyte extraction was conducted using 2% formic acid in acetonitrile and cleaned up using a hydrophillic-lipophillic balance (HLB) cartridge. The limits of detection (LOD) and quantification (LOQ) were 0.004 and 0.01 mg/kg, respectively. Matrix-matched calibration curves were linear over the calibration ranges ($0.001{\sim}0.1{\mu}g/mL$) into a blank extract with $r^2>0.99$. The recovery results for fenquinotrione and KIH-3653-M-2 ranged between 81.1 to 116.2% and 78.0 to 110.0% at different concentration levels (LOQ, $10{\times}LOQ$, $50{\times}LOQ$) with relative standard deviation (RSD) less than 4.6%. All values were corresponded with the criteria ranges requested in both the Codex (CAC/GL 40-1993, 2003) and MFDS guidelines (2016). Therefore, the proposed method can be used as an official analytical method for determination of fenquinotrione in the Republic of Korea.

• Journal of Preventive Medicine and Public Health
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• v.29 no.4 s.55
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• pp.785-799
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• 1996

We investigated the 1,004 workers who worked in a automobile factory to study the epidemiologic characterists of dermatoses due to cutting oils. Among the workers, 667(66.4%) answered the questionaire. They are belong to 5 departments of the factory-the Engine-Work(258 workers), Gasoline engine Assembly(210), Diesel engine Assembly(96), Power train Work(86), Power train Assembly(17). We measured the oil mist concentration in air of the departments and examined the workers who had dermatologic symptoms. The results were follows; 1) Oil mist concentration ; Of all measured points(52),9 points(17.2%) exeeded $5mg/m^3$- the time-weighed PEL-and one department had a upper confidence limit(95%) higher than $5mg/m^3$. 2) Dermatologists examined 213 workers. 172 of them complained any skin symptoms at that time - itching(32.5%), papule(21.6%), scale(15.7%), vesicle(12.5%) in order. The abnormal skin site found by dermatologist were palm(29.3%), finger & nail(24.6%), forearm(16.2%), back of hand(8.4%) in order. 3) As the result of physical examination, we found that 160 workers had skin diseases. Contact dermatitis was the most common; 69 workers had contact dermatitis alone(43.1%), 11 had contact dermatitis with acne(6.9%), 10 had contact dermatitis with folliculitis(6.3%), 1 had contact dermatitis with acne & folliculitis, and 1 had contact dermatitis with abnormal pigmentation. Others were folliculitis(9 workers, 5.6%), acne(8, 5.0%), folliculitis & acne (2, 1.2%), keratosis(1, 0.6%), abnormal pigmentation (1, 0.6%), and non-specific hand eczema (47, 29.3%). 4) The prevalence of any skin diseases was 34.0 pet 100 in cutting oil users, and 13.3 per 100 in non- users. Especially, the prevalence of contact dermatitis was 23.0 per 100 in cutting oil users and 23.0 per 100 in non-users. 5) We tried patch test(standard serise, oil serise, organic solvents) on 49 patients to differentiate allergic contact dermatitis from irritant contact dermatitis and found 20 were positive. 6) In a multivariate analysis(independant=age, tenure, kinds of cutting oil), the risk of skin diseases was higher in the water-based cutting oil user and both oil user than non-user or neat oil user(odds ratio were 2.16 and 2.78, respectively). And the risk of contact dermatitis was much higher at the same groups(odds ratio were 5.16 and 6.82, respectively).

• Korean journal of food and cookery science
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• v.30 no.6
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• pp.774-784
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• 2014

The purpose of this study was to present management guidelines for critical control points by analyzing microbiological hazardous elements through screening Potentially Hazardous Foods (PHF) menus in an effort improve the microbiological quality of foods prepared by restaurant operations. Steamed spinach with seasoning left at room temperature presents a range of risk temperatures which microorganisms could flourish, and it exceeded all microbiological safety limits in our study. On the other hand, steamed spinach with seasoning stored in a refrigerator had Aerobic Plate Counts of $2.86{\pm}0.5{\log}\;CFU/g$ and all other microbiological tests showed that their levels were below the limit. The standard plate counts of raw materials of lettuce and tomato were $4.66{\pm}0.4{\log}\;CFU/g$ and $3.08{\pm}0.4{\log}\;CFU/g$, respectively. Upon washing, the standard plate counts were $3.12{\pm}0.6{\log}\;CFU/g$ and $2.10{\pm}0.3{\log}\;CFU/g$, respectively, but upon washing after chlorination, those were $2.23{\pm}0.3{\log}\;CFU/g$ and $0.72{\pm}0.7{\log}\;CFU/g$, respectively. The standard plate counts of baby greens, radicchio and leek were $6.02{\pm}0.5{\log}\;CFU/g$, $5.76{\pm}0.1{\log}\;CFU/g$ and $6.83{\pm}0.5{\log}\;CFU/g$, respectively. After 5 minutes of chlorination, the standard plate counts were $4.10{\pm}0.6{\log}\;CFU/g$, $5.14{\pm}0.1{\log}\;CFU/g$ and $5.30{\pm}0.3{\log}\;CFU/g$, respectively. After 10 minutes of chlorination treatment, the standard plate counts were $2.58{\pm}0.3{\log}\;CFU/g$, $4.27{\pm}0.6{\log}\;CFU/g$, and $4.18{\pm}0.5{\log}\;CFU/g$, respectively. The microbial levels decreased as the time of chlorination increased. This study showed that the microbiological quality of foods was improved with the proper practices of time-temperature control, sanitization control, seasoning control, and personal and surface sanitization control. It also presents management guidelines for the control of potentially hazardous foods at the critical control points in the process of restaurant operations.

• Journal of Food Hygiene and Safety
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• v.34 no.2
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• pp.124-134
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• 2019

An analytical method was developed for the determination of broflanilide and its metabolites in agricultural products. Sample preparation was conducted using the QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method and LC-MS/MS (liquid chromatograph-tandem mass spectrometer). The analytes were extracted with acetonitrile and cleaned up using d-SPE (dispersive solid phase extraction) sorbents such as anhydrous magnesium sulfate, primary secondary amine (PSA) and octadecyl ($C_{18}$). The limit of detection (LOD) and quantification (LOQ) were 0.004 and 0.01 mg/kg, respectively. The recovery results for broflanilide, DM-8007 and S(PFP-OH)-8007 ranged between 90.7 to 113.7%, 88.2 to 109.7% and 79.8 to 97.8% at different concentration levels (LOQ, 10LOQ, 50LOQ) with relative standard deviation (RSD) less than 8.8%. The inter-laboratory study recovery results for broflanilide and DM-8007 and S (PFP-OH)-8007 ranged between 86.3 to 109.1%, 87.8 to 109.7% and 78.8 to 102.1%, and RSD values were also below 21%. All values were consistent with the criteria ranges requested in the Codex guidelines (CAC/GL 40-1993, 2003) and the Food and Drug Safety Evaluation guidelines (2016). Therefore, the proposed analytical method was accurate, effective and sensitive for broflanilide determination in agricultural commodities.

• Journal of the Korean Society of Food Culture
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• v.7 no.3
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• pp.259-270
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• 1992

The changes in life style today appear many ways. Many housewives turn away from home preparation of the time consuming traditional foods, such as 'Andong sikhe'. The importance, however, of succeeding the traditional cuisines is getting appreciated widely nowadays. This study aimed to investigate the preparation of Andong sikhe by use of pure culture inoculation and the improvement of storage stability by the addition of stabilizers to the product. Lactobacillus delbreuckii was selected for the pure culture inoculation in the fermentation. The changes in chemical composition such as total acidity, sugar content, amino acid and various forms of nitrogen during fermentation were determined. The changes in pH of the product, the enzyme activities and the population of lactic acid bacteria were also followed in the process of fermentation. The Lactobacillus dominated in the beginning of the fermentation but the Streptococcus out numbered the former as the fermentation proceeded. The crude protein content increased up to the 4th day of fermentation but slowly decreased there after. The pH of the product rapidly decreased to 4.2 by the 2nd day of fermentation. The total acidity reached to the 0.38% by the 2nd day of fermentation and kept on increasing slowly during the fermentation. The free sugar consisted of 6 kinds including maltose and one unknown sugar. The amino form nitrogen increased up to 38.5mg% at the 2nd day of fermentation and the product tasted best at this time. The ammonia form nitrogen, water soluble and salt soluble protein decreased during fermentation. Proline and aspartic acid were the two major free amino acids. The free methionine increased while the free lysine decreased in the process of fermentation. The major amino acids of water soluble and salt soluble protein were glutamic acid and aspartic acid. The arginine content of salt soluble protein increased as the fermentation proceeded. Linoleic, palmitic and oleic acid were the three major fatty acids and occupy 90% or more of the total fatty acids. The activities of acid protease and liquefying amylase reached to the maximum at the 4th day of fermentation while those of saccharogenic amylase and lipase reached to the peak at the 2nd day of fermentation.

• Korean Journal of Organic Agriculture
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• v.13 no.3
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• pp.315-332
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• 2005

This study was conducted to assess the nutritional value and the safety of the fermented food wastes (FFW) made by adding lactobacillus spp. and bacillus spp. at the ratio of 3:7, respectively to food wastes collected everywhere, and also to determine effects on the performances, carcass characteristics and economical profitability when FFW was fed to pigs. For swine trial, FFW was formulate to pellet by utilizing different feed ingredients, and its formulated FFW pellet was used in this feeding trial. Treatments were consisted of different ratios (T1: $100+0\%$, T2: $75+25\%$, T3: $50+50\%$, T4: $25+75\%$, T5: $0+100\%$) of FFW pellet to commercial diet. A total of 20 male pigs were allotted to treatments of five groups of four pigs per pen. Experimental period lasted for 4 months. The nutritional composition of FFW was 56.7, 19.5 and $19.5\%$ for moisture, crude protein and ether extract, respectively. Salt content was $0.39\%$. Noxious microorganisms such as salmonella and E. coli were not detected in FFW, and contents of heavy metal and aflatoxin B1 were lower than the standard. Nutritional values of FFW pellet satisfied over $100\%$ of requirements presented in official Korean feeding standard for swine. Feeding trial for pigs showed that feed intakes were significantly (P<0.05) decreased with increasing levels of FFW pellet. T2 treatment was ideal ratio under the consideration of economical value of feeds and body weight gain of pigs. For carcass characteristics, dressing rate ($\%$) was highest in T3, and carcass grades for T2, T3 and T4 treatments were estimated as 'A'. Feed cost for FFW per kg was ${\won}167.95$, which implies $52\%$ of commercial feed cost (${\won}350/kg$). Thus, this result implied the decreased feed cost in the swine farm. Conclusively, the utilization of food wastes as feed source may lead to the reduced environmental pollution and the practice of organic livestock farming. However, our results showed that excessive amount of fermented food wastes supplementation to pigs might give rise to their reduced palatability and delayed growth.