• 제목/요약/키워드: physical and microbiological changes

검색결과 19건 처리시간 0.024초

Physical and Microbiological Changes of Sliced Process Cheese Packaged in Edible Pouches during Storage

  • Ryu, Sou-Youn;Koh, Kyung-Hee;Son, Sook-Mee;Oh, Myung-Suk;Yoon, Jung-Ro;Lee, Won-Jong;Kim, Suk-Shin
    • Food Science and Biotechnology
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    • 제14권5호
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    • pp.694-697
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    • 2005
  • The objectives of this study were to compare the quality changes of cheese slices individually packed in four kinds of edible pouches in order to select the most suitable variety for individual packaging. The edible Z2 pouch (zein with oleic acid) was selected as maintaining the best cheese qualities based on the physical and microbiological changes undergone by the samples over 4-week storage at $5^{\circ}C$. The cheese sample individually packed in Z2 inner edible pouch and repacked in a plastic (OPP/LLDPE) outer pouch was not significantly different in physical and microbiological changes from that individually packed in a plastic (OPP/LLDPE) inner pouch and repacked in a plastic (OPP/LLDPE) outer pouch. Therefore, it may be concluded on the basis of the physical and microbiological evidence that the Z2 edible pouch can be used as an inner package for cheese slices when it is inside a plastic outer pouch.

고추장의 숙성 중 발효 용기가 품질변화에 미치는 영향 (Effects of Vessel on the Quality Changes during Fermentation of Kochujang)

  • 정순경;김영숙;이동선
    • 한국식품저장유통학회지
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    • 제12권3호
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    • pp.292-298
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    • 2005
  • 발효식품 담금 용기로 사용되고 있는 유리, polypropylene(PP), polyethylene terephthalate(PET), 스테인레스 용기, 옹기에 고추장을 담아 $30^{\circ}C$에서 4개월 동안 발효하는 동안 물리적, 화학적, 미생물적인 품질변화를 측정하여 담금 용기의 효과를 비교 평가하였다. 높은 기공성을 가진 옹기는 다른 용기에 비해 전체 발효기간에서 높은 호기성 세균수, 젖산균수, 효모수를 보여서 가장 왕성한 발효진행을 보였으며, 이와함께 높은 protease 활성을 유지시키고, 아미노태 질소와 유리 아미노산을 생산하였다. 아울러 옹기에 담금 한 고추장에서는 높은 총산함량과 낮은 pH를 얻게 하였으며, 환원당도 많이 생성시켰다. 이러한 변화는 발효 $2{\sim}3$개월에 완성되어졌다. 하지만 높은 기공성에도 불구하고 옹기에서 발효된 고추장은 타용기구에 비해서 수분손실과 염도상승은 현저하지 않았는데, 이는 시간의 경과에 따라 옹기벽면에서의 기공이 고추장 성분에 의하여 일부 닫혀짐에 의한 것으로 해석된다. 이러한 성분변화의 결과로 인하여 옹기에서 발효된 고추장은 관능적인 품질에서 타 용기처리구에 비해 유의적으로 우수하였다.

수삼저장중 이화학적 및 기생물학적 변화 (Physico-Chemical and Microbiological Changes during Storage of Fresh Ginseng)

  • 오훈일;노해원;도재호;김상달;홍순근
    • Journal of Ginseng Research
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    • 제5권2호
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    • pp.99-107
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    • 1981
  • Physical, chemical and microbiological changes were periodically studied during six-month storage of fresh ginseng under N2, CO2 gas or subatmospheric pressure condition. The results were summarized as follows. 1. The moisture contents of fresh ginseng gradually decreased during the first 2-month storage and thereafter generally reached at equillibrium. 2. There was no significant change in the reducing sugar content in 1-month storage, followed by$.$a decrease in between 2-and 3-month storage. Thereafter, the reducing sugar content increased at the end of 4-month storage. 3. The total sugar content increased significantly during the first 3-month storage. Under CO2 and Nr gas storage, the total sugar content gradually decreased after 3-month storage, while no significant change was observed in the samples stored under subatmospheric Pressure. Amylase activity gradually decreased as storage period increased 4. The content of saponin decreased as storage period increased, but ginsengoide Rf, Rd, Rc and Rb2 increased significantly in 1-month storage. 5. Regardless of storage methods, sprouting of ginseng and growth of microorganisms were inhibited in all samples during the first 4-month storage. However, growth of microorganisms was observed in the rhizome and injured areas of ginseng after 5-month storage in the N2 and CO2 gas atmosphere.

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Physical Methods for the Identification of Irradiated Food

  • Yang, Jae-Seung;Lee, Hae-Jung
    • Preventive Nutrition and Food Science
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    • 제3권2호
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    • pp.203-209
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    • 1998
  • The development of methods for the identification of irradiated foods helps enforce national and international regulations on labelling to ensure the consumer's free choice to buy irradiated or unirradiated foods. and the availabilityof such methods may assist the promotion of international trade in irradiated food products and help prevent abuse of the technology. A number of approaches to determine the physical , chemical, microbiological and biological changes that occur in foods treated with ionizing radiation have been studied. However no single method is universally applicable. Among physical measurements, the leading methods of indentification are electron spin resonance (ESR) spectroscopy and thermoluminescence(TL). ESR is an established non-destructive method for the analysis of free radicals from their traps and TL is the emission of light from irradiated mineral extracts by heating. Viscosity of carbohydrate polymers by causing chain breaks by irradiation, measuring the impedance of potatoes and detection of gases produced radiolytically are promising techniques for identification purposes. Irradiated water-containing foods show significant supercooling when monitored with a differential scanning calorimeter (DSC), which can be applied to identifying irradiated ones.

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Development of Cooked Rice with Garlic and Astragalus membranaceus Extract for the Health-Friendly Ready-To-Eat Product as Cook-Chill Type

  • Hyeyoon Jeong;Seyoung Ju;Hyeja Chang
    • 급식외식위생학회지
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    • 제5권1호
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    • pp.19-29
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    • 2024
  • Medicinal cooked rice with Astragalus membranaceus extract and garlic was developed as a ready-to-eat product. The response surface methodology was used to examine the effect of garlic and Astragalus membranaceus extract addition on the color, texture, and sensory properties to optimize the product. The product was also analyzed for microbiological, sensory, and physical property changes during storage.As for the color, taste, and overall acceptability, the sensory scores increased with the increase of Astragalus membranaceus extracts (p<0.05). The sensory scores for the product ranged between 9.17~9.92 and foodborne microorganism such as Bacillus cereus, Salmonella, Staphylococcu aureus, and Eschericha coli were not detected after 13 storage days. Therefore, the possible shelf life was evaluated for up to13 days of storage. When considering health and convenience are important factors in the development of new food products, the medicinal and biological effects of garlic and Astragalus membranaceus could be useful for providing healthy diet options for senior consumers. The results of sensory and microbiological tests showed the potential for the commercialization of ready-to-eat cook-chill product as an alternative of cooked rice for Asian populations and Korean senior consumer market.

Identification of Irradiated Foods by Using DNA, Immunochemical, and Biological Methods

  • Kim, Kyeung-Eun;Yang, Jae-Seung
    • Preventive Nutrition and Food Science
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    • 제4권4호
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    • pp.276-282
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    • 1999
  • Ionizing radiation is considered to be an efficient technology to improve food safety and to extend food shelf-life in the food industry, and it has been used in food processing with a number of attributes. Food labeling should be established to enable the consumer to choose food freely, based on label information. A variety of methodologies to determine the physical, chemical, microbiological, and biological changes due to irradiation has been investigated in order to discriminate the irradiated and unirradiated food products for the consumer's free choice in food selection. However, no satisfactory method has been developed so far. In this review, various approaches based on DNA, immunochemical, and biological methods are addressed.

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Effects of Various Eggshell Treatments on the Egg Quality during Storage

  • Park, Y.S.;Yoo, I.J.;Jeon, K.H.;Kim, H.K.;Chang, E.J.;Oh, H.I.
    • Asian-Australasian Journal of Animal Sciences
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    • 제16권8호
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    • pp.1224-1229
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    • 2003
  • The combined effects of washing, sanitization and coating of eggshell on the physical and microbiological quality during storage were evaluated at $4^{\circ}$ and $30^{\circ}C$. The interior qualities of the eggs were assessed by weight changes, yolk index, albumen index, Haugh unit value, and microbial contamination of egg shell and egg white during 30 days of storage in untreated, washed, or sanitized and mineral oil-coated eggs. The results suggest that these changes were faster in higher temperature ($30^{\circ}C$) than lower temperature ($4^{\circ}C$) storage, and washed eggs deteriorated faster than untreated eggs. The sanitized and coated eggs maintained the best quality during storage in all parameters measured. The shelf-life of washed, sanitized and coated eggs could be extended 4-5 fold compared to that of washed or untreated eggs.

Determination of Quality Changes throughout Process ing Steps in Chinese-style Pork Jerky

  • Chen, W.S.;Liu, D.C.;Chen, M.T.
    • Asian-Australasian Journal of Animal Sciences
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    • 제17권5호
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    • pp.700-704
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    • 2004
  • Chinese-style pork jerky is a typical intermediate moisture meat product obtained by curing, drying and roasting pork samples. The chemical, physical and microbiological characteristics of pork jerky were evaluated throughout processing. The moisture content varied from 72.5% to 23.4 or 19.6% and aw varied form 0.97 to 0.74 or 0.72 in accordance with processing steps. The pork jerky roasted at $200^{\circ}C$ had higher shear value than roasted at $150^{\circ}C$ because the moisture content and aw of the former sample was lower than the later sample. The nitrite losses during whole processing steps amount to nearly 50%. The TBA value of pork jerky varied from 0.34 to 9.25 or 9.83 mg of malonaldehyde depended on processing steps. The VBN value of pork jerky ranging from 0.25 to 22.4 or 23.5 mg/kg depended upon processing steps. The ATPase activity of myofibrillar proteins during processing steps were partly or entirely denatured by the heat-drying or heat-roasting treatment. A gradual decrease in microorganism count during processing of pork jerky was also observed.

흙배합비를 달리하여 기공율이 조절된 담금용기 항아리에서의 간장 발효 (Fermentation of Kanjang, Korean Soy Sauce, in Porosity-Controlled Earthenwares with Changing the Mixing Ratio of Raw Soils)

  • 정순경;이광수;이동선
    • 한국식품과학회지
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    • 제38권2호
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    • pp.215-221
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    • 2006
  • 담금용기로서의 항아리의 간장발효특성을 규명하기 위해 원료 흙인 옹기토, 황토와 분쇄토의 배합비를 달리하여 옹기의 기공율을 조절한 항아리를 제작한 후 각각의 항아리에서 간장을 4개월간 숙성시키는 과정 동안 나타나는 이화학적인 변화, 미생물 생육 및 관능검사를 옹기의 기공율이 간장발효에 미치는 영향을 확인하고자 하였다. 기공율 조절을 위해 황토와 분쇄토를 동량 혼합한 흙(RP soil)을 각각 0, 40와 60%를 옹기토와 배합하여 세가지 종류의 항아리를 제작하였다. 숙성조건은 $30^{\circ}C$ 숙성실에서 4개원 동안 진행하였다. 기공율에 따른 변화를 보인 것은 수분손실, 염함량변화, pH 및 총산도, 단백질 분해효소 활성 변화, 미생물변화, 핵산, 색도변화 및 관능검사 결과였고 기공율이 가장 낮은 0% RP soil 항아리에서 숙성시킨 간장이 보다 긍정적인 결과를 보였으며 그 다음으로 각각 40와 60% RP soil을 함유한 항아리 순 이였다. 반면에 총질소 함량의 변화는 처리구간별에 따른 차이를 볼 수가 없었으며 총유리아미노산 함량은 숙성 4개월째 0% RP soil 항아리에서 4,848 mg/100 g로서 40% RP soil 처리구 5,434 mg/100 g, 60% RP soil 처리구 5,477 mg/100 g에 비해 상대적으로 낮은 함량을 보였다. 하지만 0% RP soil 항아리는 수분 손실이 처리구들 중에서 가장 낮은 약 28%로서 다른 처리구에서 거의 40%의 수분손실을 보인 결과를 고려하면 수분손실에 따른 영향이 기공율보다 더 큰 영향을 준 것으로 사료되었다. 한편, 맛난 맛을 내는 glutamic acid의 비는 0% RP soil 항아리가 다른 처리구에 비해 상대적으로 조금 높은 함량을 보였다. 이와 같이 이화학적으로 보다 긍정적인 결과를 얻은 0% RP soil 항아리에서 발효시킨 간장은 관능검사 결과에 있어서도 색, 향기, 맛과 더불어 전체적인 평가에서 모두 가장 높은 평가를 받았다.

Quality attributes and shelf-life of freshly cut beef coated with waste feather keratin-ginger starch composite enriched with avocado peel polyphenolic-rich extract

  • Olarewaju M Oluba;Samuel I Ojeaburu;Opeyemi A Bayo-Olorunmeke;Georgina Erifeta;Sunday J Josiah
    • 한국식품저장유통학회지
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    • 제31권1호
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    • pp.1-14
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    • 2024
  • The utilization of coatings composed of bio-based materials in the processing and preservation of meat presents an environmentally conscious, secure, cost-effective, and superior method for prolonging the storage life of meat while also preserving its nutritional value. In this study, changes in physical, chemical, and microbiological characteristics of freshly cut beef coated with distilled water (control) and keratin-starch composites (K-S) functionalized with 0.0-, 0.2-, 0.6-, and 1.0-mL avocado peel polyphenolic-rich extract (APPPE) kept at 4℃ for 12 days were evaluated periodically at 3-day interval using standard techniques. Keratin was extracted from waste feathers, while starch was obtained from ginger rhizomes. Following a 12-day storage period, beef coated with APPPE-enriched K-S composites exhibited a significant (p<0.05) improvement in shelf life by minimizing deteriorative changes in pH and color (as determined by metmyoglobin level) in addition to inhibiting oxidative changes in lipids (as determined by TBARS level) and proteins (protein carbonyl level) in comparison to control and K-S composite without APPPE. Furthermore, microbial growth was significantly (p<0.05) suppressed in meat coated with K-S composite functionalized with APE at 0.6 and 1.0 mL compared to the control. The study suggested that APPPE-enriched K-S composite could offer an eco-friendly and safe food preservation technique for fresh meat.