• Preventive Nutrition and Food Science
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• 제12권1호
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• pp.40-45
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• 2007

The effects of drying methods on the physicochemical properties of chaga (Inonotus obliquus) mushroom powder were investigated. Scanning electron micrograph revealed that freeze drying produced smaller particle- sized samples which in turn resulted in higher porosity than did vacuum and hot-air drying. Samples prepared by freeze drying showed a significantly higher L*-value as compared with those prepared by hot-air drying and vacuum drying (p<0.05). The lightness (L*-value) significantly decreased with increasing relative humidity and storage temperature regardless of drying method (p<0.05). The yellowness (b*-value) increased significantly with increasing relative humidity (p<0.05). Browning index was significantly lower in samples prepared by freeze drying (p<0.05) but not significantly different between samples dried by hot-air and vacuum drying. Freeze dried sample exhibited a significantly higher degree of rehydration than other samples (p<0.05) probably due to the small particle size. Water solubility of the freeze dried sample was higher than those of the other methods while swelling ratio of the same sample appeared to be lower than those of others. Freeze dried chaga mushroom powder contained significantly lower amount of total phenolics and total sugar as compared to other samples (p<0.05).

• 한국식품조리과학회지
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• 제10권3호
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• pp.225-231
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• 1994

This study was intended to observe the effect of cooked glutinous rice flour and soused shrimp on the fermentation of Kimchi samples were fermented for 11 days at 10$^{\circ}C$ after they were previously fermented for 6 hours at 20$^{\circ}C$. Changes of pH, total acidity, salt content, reducing sugar content, free amino acid content, total vitamin C content, and ascorbic acid content were measured. The results were as follows; 1. Soused shrimp and glutinous rice flour added in Kimchi acted as lactobacilli growth enhancer during fermentation. 2. Initial cincentrations of redng sugars in Kimch samples with no soused shrimp, 5% and 10% sosed shrimp were 7.5~8.3 mg/g, 3.0~4.7 mg/g and 0.5~0.6 mg/g respectively. Kinchi samples with glutinous rice flour showed higher reducing sugar contents than Kimchi samples without it. 3. Free amino acid contents in Kimchi samples gradually decreased during fermentation at 10$^{\circ}C$. According to their soused shrimp concentration, contents of free amino acid of Kimchi samples were significantly different. And Kimchi samples with glutinous rice flour showed lower free amino acid contents than Kimchi samples without it. 4. Total vitamin C contentrations of Kimchi samples were 24.5~28.0 mg% at the initial stage of fermentation and 15.0~19.2 mg% at the final stage of fermentation. During the fermentation of Kimchi, the higher soused shrimp concentration, the less total vitamin C contents were remained. 5. During the fermentation, ascorbic acid contents of Kimchi samples were not affected by soused shrimp and glutinous rice flour.

• 한국포장학회지
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• 제10권1호
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• pp.7-14
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• 2004

Migration behavior of selected solvents and food samples showed differences of the chemical structures and polarities, the food samples which have similar polar expresses more higher affinity than different polar degrees. Water which is polar has a highest partitioning coefficient values on polar isopropanol, and oil which is nonpolar has highest partitioning value on non-polar toluene. The increasing order of partitioning values was accord with increasing water contents in food samples. It is showed that the wheat flour with 13.2% moisture content has the highest partitioning coefficient values on the isopropanol with -OH. Kp value of sugar showed remarkable lower partitioning coefficient values than other food samples due to high degree crystallinity. This phenomenon can be predictable with ${\delta}$ values, because order of partitioning coefficient values which comes out through the experiment and the sequence of Hildebrand solubility parameter value difference between food sample and printing ink solvent correspond almost. This Hildebrand solubility parameter value can be easily applied to the food package industry because the effect of food-safety can be considered without passing through complicated steps by using this method.

• Journal of Microbiology and Biotechnology
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• 제28권2호
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• pp.210-217
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• 2018

A one-step multiplex reverse transcription PCR (RT-PCR) method comprising six primer sets (for the detection of norovirus GI and GII, hepatitis A virus, rotavirus, and astrovirus) was developed to simultaneously detect four kinds of pathogenic viruses. The size of the PCR products for norovirus GI and GII, hepatitis A virus (VP3/VP1 and P2A regions), rotavirus, and astrovirus were 330, 164, 244, 198, 629, and 449 bp, respectively. The RT-PCR with the six primer sets showed specificity for the pathogenic viruses. The detection limit of the developed multiplex RT-PCR, as evaluated using serially diluted viral RNAs, was comparable to that of one-step single RT-PCR. Moreover, this multiplex RT-PCR was evaluated using food samples such as water, oysters, lettuce, and vegetable product. These food samples were artificially spiked with the four kinds of viruses in diverse combinations, and the spiked viruses in all food samples were detected successfully.

• Nutrition Research and Practice
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• 제2권3호
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• pp.165-170
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• 2008

Protein-energy malnutrition is regarded as one of the public health problems in developing countries as a result of poor feeding practices due to poverty. This study, therefore, aimed at evaluating nutritional quality of a potential weaning food formulated from locally available food materials. The cooking banana fruit(CB) and bambara groundnut seeds(BG) were purchased from local market in Akure, Ondo State, Nigeria. The CB and BG were processed into flours, mixed in ratios of 90:10, 80:20, 70:30 and 60:40 and subjected into proximate, sensory and biochemical analyses using standard procedures. Nutrend(a commercial formula) and ogi(corn gruel, a traditional weaning food) were used as control. The nutritient composition(g/100 g) of the food samples were ranged as follows: moisture 2.94-6.94, protein 7.02-16.0, ash 1.76-2.99, fat 0.76-8.45, fibre 1.52-3.75, carbohydrate 63.84-88.43 and energy 1569.8-1665.7 kcal. The biological value(BV), net protein retention(NPR), protein efficiency ratio(PER) and feed efficiency ratio(FER) of the experimental food samples were significantly(p<0.05) lower than nutrend, but higher than ogi. The haematological variables of rats fed with formulated food samples, commercial formula(nutrend) and traditional weaning food(ogi) were not significantly(p>0.05) influenced by the dietary treatment. However, the values obtained for red blood cell(RBC), white blood cell(WBC), pack cell volume(PCV) and erythrocyte sedimentation rate(ESR) were higher in the experimental food samples than the commercial food. The growth rate of animals fed with experimental food samples were lower than those fed with the nutrend, but higher than those fed with ogi. In conclusion, the nutritional quality of CB and fermented BG mix of 60:40 ratio was better than ogi; and comparable to the nutrend. This implies that it can be used to replace low quality traditional weaning food and the expensive commercial weaning formula.

• Journal of Microbiology and Biotechnology
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• 제19권11호
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• pp.1415-1420
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• 2009

The aim of the present study was to examine the prevalence of thermophilic Campylobacter spp. (Campylobacter jejuni and Campylobacter coli) in soil, poultry manure, irrigation water, and freshly harvested vegetables from vegetable farms in Malaysia. C. jejuni was detected in 30.4% and 2.7% of the soil samples, 57.1 % and 0% of the manure samples, and 18.8% and 3% of the vegetable samples from farm A and farm B, respectively, when using the MPN-PCR method. Campylobacter spp. was not found in any of the irrigation water samples tested. Therefore, the present results indicate that the aged manure used by farm A was more contaminated than the composted manure used by farm B. Mostly, the leafy and root vegetables were contaminated. C. coli was not detected in any of the samples tested in the current study. Both farms tested in this study were found to be contaminated by campylobacters, thereby posing a potential risk for raw vegetable consumption in Malaysia. The present results also provide baseline data on Campylobacter contamination at the farm level.

• Asian-Australasian Journal of Animal Sciences
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• 제15권8호
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• pp.1204-1209
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• 2002

Polymerization of heated or unheated pig skin collagen using microbial transglutaminase (MTGase) was investigated. Pig skin collagen samples were heated or left unheated, then enzymatically polymerized with MTGase. SDS-PAGE was conducted to confirm the intermolecular polymer and the results showed similar bands between samples without MTGase and unheated samples with MTGase. The polymerized product of pig skin collagen was not formed in unheated samples, even when MTGase was added during incubation. Different results were obtained from samples heated at $80^{\circ}C$ and $100^{\circ}C$ for 2 min, whereas the SDS-PAGE pattern indicated that a polymer band was generated in both cases. The heat treatment successfully modified the native structure of collagen and also made collagen more reactable in the MTGase polymerization system. Scanning Electron Microscope (SEM) investigation of pig skin collagen showed a biopolymer structure through intermolecular collagen crosslinking, while there were no intermolecular crosslinks in samples not treated with MTGase. There were no significant differences in fibril diameter between treated samples and controls. These results suggest that heat treatment of native pig skin collagen enhanced the polymerization capability of MTGase.

• 한국식품조리과학회지
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• 제27권6호
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• pp.671-680
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• 2011

In this study, frying mix was prepared containing 0.5, 1.0, 1.5 or 2.0% brown rice fiber(BRF). The samples along with a control were then compared regarding their quality characteristics, including pasting properties, spreadability, pick-up ratio, color, textural characteristics, moisture and oil contents, and sensory qualities, all to determine the optimal ratio of BRF. For the pasting properties of frying mix, the control group was evidenced by a significantly higher peak viscosity, through viscosity, and final viscosity than that observed in the BRF samples. Breakdown was the highest at the 1.0% addition level, and time to peak viscosity and pasting temperature were maximal with the 0.5% addition. There was no significant difference in setback among the experiments. Spreadability and pick-up ratio of frying batter were not significantly different among the samples. As the BRF content increased, the lightness, greenness decreased, whereas yellowness increased. The BRF samples presented significantly higher hardness of fried batter than the control group and there was no significant difference in crispiness among the samples. Moisture content of fried sweet potato decreased with increasing BRF and oil content was the maximum on the control group. In the sensory evaluation, appearance, color, flavor, savory taste, yellowishness, coating thickness, off-flavor, and oiliness were not significantly different among the fried sweet potato samples. Bindingness, crispiness, and chewiness were highest in the control samples but minimal at a addition level of 2.0%. The control group evidenced significantly higher overall acceptability than were observed in the BRF samples. In conclusion, the results demonstrated that 0.5~1.0% BRF may prove quite useful as a additive for frying mix in the preparation of fried sweet potato and may provide favorable textural and functional properties.

• 한국식품위생안전성학회지
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• 제29권1호
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• pp.16-20
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• 2014

시중에 유통 중인 샐러드와 김밥을 각각 100종 수거하여 B. cereus 함량을 정량분석하였다. 샐러드는 불검출이 54종이었으며 10 CFU/g 이하가 8종, 100 CFU/g 이하가 25종, 1,000 CFU/g 이하가 11종이었으며 1,000 CFU/g 이상인 것이 2종이었다. 샐러드의 대한 모니터링 결과 평균은 1.18 log CFU/g 이었으며 표준편차는 0.71 log CFU/g이었다. 김밥에서는 100개의 검체중 20개의 검체에서 B. cereus가 검출되었으며 평균은 1.01 log CFU/g 이었으며 표준편차는 0.71 log CFU/g이었다. 모니터링 결과를 이용하여 통계적 검체채취 방법을 수립하고자 하였다. 검체채취 방법은 국제미생물위원회에서 제공하는 검체채취프로그램인 NEW sampleplan program을 이용하였으며 검체갯수를 고정한 후 미생물 기준인 m과 M, 그리고 허용한계값인 c 값을 변화하면서 산출되는 합격률이 0.95에 가장 근사한 값을 선정하였다. 그 결과 샐러드, 김밥에서의 가장 적합한 검체채취 기준은 3분법을 사용하는 것으로 n = 5, c = 0, m = 1,000, M = 10,000과 n = 5, c = 2, m = 100, M = 1,000의 기준이 설정되었다. 특히 후자에 서술된 기준은 현재 뉴질랜드에서 즉석섭취식품에서의 B. cereus에 대한 규격으로 사용하고 있어 국제적인 경향에도 부합함을 알 수 있었다.

• 한국축산식품학회지
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• 제30권2호
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• pp.179-184
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• 2010

Escherichia coli O157:H7 is a food-borne pathogen that causes bloody diarrhea, hemorrhagic colitis, and hemolytic uremic syndrome (HUS). We compared three selective media and evaluated the performance of immunomagnetic separation (IMS) for the detection of low levels of E. coli O157:H7 in ground beef and radish sprouts with different levels of background flora. Bulk food samples (500 g for each trial) were artificially inoculated with nalidixic acid-resistant E. coli O157:H7 at the lowest dose that would generate 20 partial-positive samples of 25 g each. All samples were homogenized in mTSB (225 mL) and incubated overnight at $37^{\circ}C$. IMS was performed using the enriched mTSB samples (1 mL) along with conventional spreads plated onto three different selective media: Sorbitol MacConkey agar (SMAC), Sorbitol MacConkey agar with cefixime and tellulite (CT-SMAC), and Sorbitol MacConkey agar with nalidixic acid (NAL-SMAC) as the gold standard. Two suspicious colonies from each medium were selected and confirmed usinga serological test after transfer to tryptic soy broth with yeast extract (TSAYE). CT-SMAC was better than SMAC for detecting E. coli O157:H7 in all food types. Although there was no statistical difference in the number of positive samples when using IMS vs. non-IMS techniques, more positive samples were detected when IMS was used in both ground beef and radish sprouts. It appears that the improvement was more significant in radish sprouts, which had a higher level of background flora than ground beef. The results also suggest that the combination of CT-SMAC and IMS is sufficient to recover low levels of E. coli O157:H7 in high background flora food samples.