• Title/Summary/Keyword: improved food

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Improved Detection of Viable Escherichia coli O157:H7 in Milk by Using Reverse Transcriptase-PCR

  • Choi, Suk-Ho;Lee, Seung-Bae
    • Food Science of Animal Resources
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    • v.31 no.2
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    • pp.158-165
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    • 2011
  • A sensitive reverse transcriptase-PCR (RT-PCR) method to detect viable Escherichia coli O157:H7 in milk was established. The primer sets were designed based on the nucleotide sequences of the rfbE (per) and wbdN genes in the O157 antigen gene cluster of E. coli O157:H7. RT-PCR using five different primer sets yielded DNA with sizes of 655, 518, 450, and 149-bp, respectively. All five of the E. coli O157:H7 strains were detected by RT-PCR, but 11 other bacterial species were not. The sensitivity of RT-PCR was improved by adding yeast tRNA as a carrier to the crude RNA extract. The RT-PCR amplifying the 149-bp DNA fragment was the most sensitive for detecting E. coli O157:H7 and the most refractory to the bactericidal treatments. Heat treatment at $65^{\circ}C$ for 30 min was the least inhibitory of all bactericidal treatments. Treatment with RNase A strongly inhibited the RT-PCR of heated milk but not unheated milk. This study described RT-PCR methods that are specific and sensitive with a detection limit of 10 E. coli O157:H7 cells, and showed that pre-treating milk samples with RNase A improved the specificity to detect viable bacteria by RT-PCR.

Production of Mirin by Mutants of Aspergillus sp. (Aspergillus sp.의 변이주에 의한 미린의 생산)

  • 류병호;신동분;빈재훈;박형선
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.22 no.5
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    • pp.636-642
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    • 1993
  • To improve the quality of mirin, various molds were screened for mutants with high acid carboxypeptidase (ACPase) by the method of ultraviolet radiation. Mutants, Aspergillus oryzae 9-12 and Aspergillus shiroussamii 6082-60 showed activities of ACPase about 2~6 times higher than their parent strains. Aspergillus oryzae 9-12 and Aspergillus shirosamii 6082-60 were the most suitable strains for preparing koji in mirin by the conventional or improved methods. The results showed that total sugar, reducing sugar and total nitrogen were almost the same values in mirin prepared by both methods. The yield of mirin was higher in the improved method than in the conventional method. The clouding formation of mirin appeared in the conventional method ; however, mirin prepared with the mutant koji by the improved method did not show clouding formation.

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Changes in lipid component and quantitative measurement of carbonyl compound during Doenjang fermentation (된장 숙성 중 지질의 변화 및 카보닐 화합물의 함량 변화)

  • 강정희;이혜수
    • Korean journal of food and cookery science
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    • v.10 no.1
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    • pp.51-56
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    • 1994
  • Conventional Doenjang, improved Doenjang prepared with Asp. oryzae were made to investigate the changes in the lipid content, and the carbonyl compounds during fermentation. Total lipid contents of conventional Doenjang increased slowly during fermentation, and that of the improved Doenjang increased at first, but showed sharp decrease at moment and then increased. Triglyceride contents of all samples decreased remarkedly during fermentation. Conversely, free acid contents increased. From the result of quantitative analysis of fatty acid by gas chromatography, saturated fatty acid ratio of total lipid in conventional Doenjang increased at early stages and then decreased, but unsaturated fatty acid ratio showed the reverse phenomenon. Saturated fatty acid in improved Doenjang increased during the fermentation but unsaturated fatty acid decreased by degrees. The concentration of total and monocarbonyl compounds in the fermented Doenjang were comparably higher than that found in raw Boenjang. Sensory evaluation revealed that off flavor had a negative effect on overall eating quality of Doenjang and total carbonyl content was related to the off flavor.

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Effects of Emulsifiers on the Quality Characteristics of Yackwa (유화제가 약과의 품질에 미치는 효과)

  • 이수연;김명애
    • Korean journal of food and cookery science
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    • v.18 no.3
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    • pp.333-339
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    • 2002
  • This study was conducted to examine the effect of emulsifiers on the quality characteristics of Yackwa. Lecithin and various sucrose fatty acid esters (S-570, S-970, S-1570) were used as emulsifiers. The addition of emulsifiers to Yackwa decreased the hardness, cohesiveness, springiness and gumminess, but increased the brittleness. This tendency was most distinct by the addition of S-970. All sensory characteristics of Yackwa such as color, smooth surface, smell, internal layer formation, softness and overall quality, were improved greatly by the addition of emulsifiers. As a result, the mechanical and sensory characteristics of Yackwa were improved by the addition of the emulsifiers, and sucrose fatty acid esters showed better results than lecithin.

Role of Fermentation in Improving Nutritional Quality of Soybean Meal - A Review

  • Mukherjee, Runni;Chakraborty, Runu;Dutta, Abhishek
    • Asian-Australasian Journal of Animal Sciences
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    • v.29 no.11
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    • pp.1523-1529
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    • 2016
  • Soybean meal (SBM), a commonly used protein source for animal feed, contains anti-nutritional factors such as trypsin inhibitor, phytate, oligosaccharides among others, which limit its utilization. Microbial fermentation using bacteria or fungi has the capability to improve nutritional value of SBM by altering the native composition. Both submerged and solid state fermentation processes can be used for this purpose. Bacterial and fungal fermentations result in degradation of various anti-nutritional factors, an increase in amount of small-sized peptides and improved content of both essential and non-essential amino acids. However, the resulting fermented products vary in levels of nutritional components as the two species used for fermentation differ in their metabolic activities. Compared to SBM, feeding non-ruminants with fermented SBM has several beneficial effects including increased average daily gain, improved growth performance, better protein digestibility, decreased immunological reactivity and undesirable morphological changes like absence of granulated pinocytotic vacuoles.

Effects of Packaging on Storage Stability and Chlorophyll Contents of Dried, Roasted and Roasted-Seasoned Laver during Storage (포장지에 따른 건조, 구이, 조미김의 저장 안전성과 Chlorophyll 함량에 관한 연구)

  • 이숙경
    • Journal of Food Hygiene and Safety
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    • v.14 no.2
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    • pp.134-139
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    • 1999
  • The relationship between storage stability and chlorophyll contents of dried laver(DL), roasted laver(RL) and roasted seasoned laver(RSL) according to packaging during storage at 20$\pm$0.5$^{\circ}C$ were investigated by measuring the acid value(AV) and the peroxide value(POV). There results are as follows; 1.The storage stability was decreased in the rank of 0 < 3< 6 < 9 months by storage term, RL < DL < RSL by the kind of laver products and PP/PE/AL/PE/LLDPE(Al) < PP/PE(PP) y packaging. 2. When the silica gel was added to RSL, the storage stability was improved. The more the addition level of silica gel was increased, the more the storage stability was improved. The rank order was 2g < 4g in RSL. 3. Reduction of the total chlorophyll content in RSL were deacreased to 10% when packed with Al and 24% when packed with PP.

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Evaluation of the Effects on Food Service Quality and Food Purchasing Attitudes According to the LOHAS level of School Foodservice Employees (학교급식 종사자의 로하스(LOHAS)수준이 식재료 구매태도 및 급식품질에 미치는 영향 연구)

  • Lee, Yeon-Jung
    • Korean journal of food and cookery science
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    • v.25 no.5
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    • pp.564-574
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    • 2009
  • This study was conducted to evaluate the effects of the LOHAS index value of school food service employees on the purchase of food materials and foodservice quality. The subjects consisted of 566 foodservice employees. The findings were as follows. (1) The foodservice employee's LOHAS index fell within that of a NOMADICS group with an average of 72.18 points out of 100 points. (2) When the age, working experience and LOHAS index of the foodservice employees was high, the necessity, view, interest and recognition of LOHAS introduction for the improvement of the foodservice environment was high. (3) The amount of environmentally-friendly food materials purchased by foodservice employees was high, when they had a high LOHAS index. (4) High foodservice quality management items of foodservice employees were 'sanitation management' (3.87 points) and 'human resource management' (3.84 points), whereas 'menu management' (3.57 points) and 'food material and inspection management' (3.61 points) scored low. (5) The LOHAS index of foodservice employees has a significant impact on the purchase intention of environmentally-friendly food materials in LOHAS and NOMADICS groups. (6) This study confirmed that a higher LOHAS index of foodservice employees was associated with higher foodservice quality management behavior, which leads to an improved quality of foodservice.

Food Preservation Technology at Subzero Temperatures: A Review

  • Shafel, Tim;Lee, Seung Hyun;Jun, Soojin
    • Journal of Biosystems Engineering
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    • v.40 no.3
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    • pp.261-270
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    • 2015
  • Purpose: Cold storage is the most popular method used to preserve highly perishable foods such as beef and fish. However, at refrigeration temperatures, the shelf life of these foods is limited, and spoilage leads to massive food waste. Moreover, freezing significantly affects the food's properties. Ice crystallization and growth during freezing can cause irreversible textural damage to foods through volumetric expansion, moisture migration induced by osmotic pressure gradients, and concentration of solutes,which can lead to protein denaturation. Methods: Although freezing can preserve perishable foods for months, these disruptive changes decrease the consumer's perception of the food's quality. Therefore, the development and testing of new and improved cold storage technologies is a worthwhile pursuit. Results: The process of maintaining a food product in an unfrozen state below its equilibrium freezing temperature is known as supercooling. As supercooling has been shown to offer a considerable improvement over refrigeration for extending a perishable product's shelf life, implementation of supercooling in households and commercial refrigeration units would help diminish food waste. Conclusions: A commercially viable supercooling unit for all perishable food items is currently being developed and fabricated. Buildup of this technology will provide a meaningful improvement in the cold storage of perishable foods, and will have a significant impact on the refrigeration market as a whole.

The Changes of Dish Consumption Frequencies, Dietary Attitudes and Health-Nutrition Risk for Single Living Female Elderly on Food-Aid Program (독거 여자노인의 식품공급프로그램 실시 후 음식섭취빈도, 식태도 및 영양위험정도 변화)

  • Son, Suk-Mi;Park, Jin-Gyeong
    • Journal of the Korean Dietetic Association
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    • v.11 no.3
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    • pp.286-298
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    • 2005
  • This study aimed to estimate the effect of the home based food supplying program in single living female elderly on the basis of depression, Health and Nutrition Risk Index, dietary attitude and dish consumption frequencies. The Food Supplying Program was carried out for 8 months for 27 single living female elderly from lower income status in Bucheon city. Main supplied foods were consisted with soymilk, vegetables, fruits and fish. The effect of the food supplying program were analyzed for 22 elderly who completed the program (group supplied with food : GSF) compared to the group not supplied with food (GNSF). The results of this study were as follows: Degree of depression estimated with depression score and Health-Nutrition Risk Index were decreased and the scores of dietary attitude and behaviors were increased for GSF after 8 months. However these improvements were not shown in the GNSF. GSF showed significantly increased consumption frequencies in soybean milk, tangerine, stir fried anchovy and yogurt, where as GNSF was observed with the decreasing trend in most of the dishes. In conclusion, home based food supplying program for single living female elderly not only increased the consumption frequencies of some dishes but also improved depression rate, Health and Nutrition Risk Index and dietary behavior concomitantly.

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Survey on the Lifestyle Factors, Food Habits and Dietary Nutrient Intake of College Students - Before and after nutrition education - (대학생의 생활습관요인, 식습관 및 영양소섭취 조사 - 영양교육 전후를 중심으로 -)

  • Won, Sun-Im;Lee, Seung-Lim
    • Journal of the Korean Society of Food Culture
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    • v.34 no.1
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    • pp.44-52
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    • 2019
  • This study examined the lifestyle factors, dietary attitudes, food habits, and dietary nutrition intake of college students before and after nutrition education. A total of 44 college students were recruited and a questionnaire survey was conducted. Dietary nutrient consumption was obtained from the one day 24-hr recall. Scores on 'Concerns about health (p<0.05)', 'Regular exercise (p<0.01)', and number of steps (p<0.001) were significantly higher after-training. The dietary attitude (31.3 vs. 33.7, p<0.01) and food habits (53.5 vs. 59.7, p<0.01) were significantly higher after-training. The scores on 'Eating a lot of food that I want to eat is more important than nutrition (p<0.01)', 'I am interested in information on nutrition and health (p<0.01)', 'Have three meals a day (p<0.01)', 'Have breakfast regularly (p<0.01)', 'Drink milk every day (p<0.001)', 'Have fruits every day (p<0.05)', and 'Apply nutrition knowledge to daily life (p<0.001)' were significantly higher after-training. Among the nutrients intakes, the protein (p<0.05), vitamin C (p<0.01), and calcium (p<0.001) were significantly higher after-training. Nutrition education improved the lifestyle factors, dietary attitudes, food habits, and dietary nutrition intakes.