Microbial populations of total aerobic bacteria -and coliforming bacteria, TBA, Hunter's color value, heme pigments, muscle protein solubility, cooking loss and shear force were investigated for evaluating the shelf life of chicken legs gamma-irradiated at doses of 1, 3, 5 and 10 kGy with air-contained and vacuum-packaged methods. The initial microbial populations decreased with gamma irradiation depending upon the dose, and microorganisms in the vacuum-packaged samples were inhibited more than those in the air-contained samples. TBA values were higher in the air-contained samples than in the vacuum-packaged samples. Hunter's L and a values of the surface and inside of the legs increased by gamma irradiation, showing a bright red color and the red color was maintained during the storage of both samples. The concentrations of oxymyoglobin among the heme pigments increased by gamma irradiation. Muscle protein solubility slightly increased by increasing the applied dose. There were no significant differences in the cooking loss and shear force values. In conclusion, the combination of gamma irradiation and vacuum-packaging could extend the shelf life of chilled chicken without deterioration of the quality.

유부의 가공공정에 대한 위해분석을 통한 위생관리방안을 모색하기 위하여 가공공정별 시설?설비와 작업장 환경 및 원재료와 가공공정별 시료에 대한 미생물 변화와 오염원인을 분석하였으며, 포장유부를 10℃에서 자장하면서 저장수명을 예측하고 이의 적절한 평가를 위한 품질지표를 도출코자 하였다. 가공공정의 효율성을 도모하고 최종제품의 저장수명을 개선하기 위해서는 가공공정 특히 사용용수, 침지, 성형, 절단, 유탕이후의 공정에서의 작업장 환경시설?설비에 대한 위생관리대책과 침지와 성형공정에서의 미생물 증식 억제방안의 마련이 필요하였다. 유부의 저장수명을 예측하기 위한 품질지표로는 조직감 같은 관능지표와 육안적 곰팡이 발생 및 일반세균수가 매우 유용하게 이용 것으로 판단되었으며, 유부의 저장수명은 최대 6일로 예측되었다. 이러한 연구는 유부의 가공조건 설정과 저장수명 평가에 대해서 적절한 기초자료로 활용될 수 있을 것으로 기대된다.

The quality changes of hams and sausages in refrigerated storage were investigated. Seven types of hams and six types of sausages produced in Korea were collected from markets and stored at 10℃ according to the Food Code of Korea, and then chemical, microbiological, textural and sensory characteristics were evaluated at 30, 40 and 50 days. The proximal analysis showed considerable variation in fat with less variation in moisture and protein. The pH values of hams and sausages slightly changed with no consistent difference. Water activity values of all samples except one type of sausage were consistent over time in refrigerated storage. No purge losses of hams were observed except two types of samples in the intial stage. Several types of sausages showed purge losses with no consistency and one type of sausage showed consistent purge losses (0.44-11.29%) during the storage. The volatile basic nitrogen (VBN) content of hams and sausages was still within 20 mg% (Standard and Specification of Korea) on the 50th day, although the VBN of all samples significantly increased over time (p$lt;0.05). The thiobarbituric acid (TBA) values of hams and sausages were well below 1.0 during the storage, although the TBA values of all samples significantly increased (p$lt;0.05). However it was noticed that one type of ham and two types of sausages showed TBA values of 0.945, 0.928 and 0.978, respectively. All the standard plate counts (SPCs) of hams during the storage period showed a level below 30 CFU/g except one type of sample with 10³ CFU/g at 50 days. All the SPCs of sausages showed a level below 50 CFU/g except one type of sample with 10² CFU/g and two types of samples with 10⁴ CFU/g on the 50th day. Coliform groups were not counted in all samples during the storage. Instrumental texture analysis showed that springiness, cohesiveness, chewiness, gumminess and adhesiveness slightly changed with no consistent difference. The hardness of the hams showed a decreasing tendency, and the hardness of the sausages an increasing tendency with no significant difference. Sensory evaluation for color, flavor, taste, texture and overall acceptability showed decreasing tendencies over time (p$lt;0.05). The scores of the five sensory characteristics maintained the medium level of quality at the termination of the experiment. Although the results indicated that the ham and sausage samples were acceptable after the 50 days' storage at 10℃, the shelf-life of the samples should be determined considering the rapid growth of bacteria and the high TBA values at 50 days.

Based on microbiological-chemical test results under simulated time-temperature conditions, total plate count, coliform and volatile basic nitrogen were selected as effective quality indicators for estimating probable shelf-life of Kim Pab dosirak marketed in convenience stores, and shelf-life at each storage temperature was calculated from regression equation between effective quality indicator standard limit and storage time. Estimated shelf-lives of Kim Pab Dosirak were 27, 3 and 2 hours respectively under 10℃, 20℃ and 30℃. Because shelf-life was especially affected by initial values, regression analysis between initial effective quality indicator values and storage hours was performed for the estimation of probable shelf-life of Kim Pab during storage at 10, 20 or 30℃.

Quality changes of sausages in refrigerated storage for 60 days were investigated. Nine types of sausages produced in Korea were stored at 4℃(3-5℃), and then chemical, microbiological, and sensory characteristics were evaluated on every 10 days. The proximate analysis showed considerable variation in fat (23.97%, 17.10-30.20%) with less variation in moisture (51.96%, 48.10-66.30%) and protein (12.96%, 11.40-13.95%). pH value decreased over time averaging from 6.31 to 6.22 with no significant difference. Water activity was consistent over refrigerated storage averaging 0.95. Volatile basic nitrogen (VBN) values were still within 20 mg% though VBN for all types significantly increased over time (p$lt;0.05). Thiobarbituric acid (TBA) values were well below 1.0 though TBA showed significant differences among storage periods (p$lt;0.05). Standard plate counts (SPCs) significantly increased during storage (p$lt;0.05) while coliform group was not counted in all cases. SPCs reached 10^5 CFU/g in two types after 50 days' storage and were below 10^6 CFU/g in all types after 60 days' storage. Instrumental texture analysis showed that springiness, adheaiveneas, and hardness significantly decreased over the 60-day storage period (p$lt;0.05) while cohesiveness, chewiness and gumminesa did not change. Lightness, redness and yellowness of the internal Hunter color significantly decreased over time (p$lt;0.05) while no change was observed in external color. Sensory profile showed that flavor, taste, texture and overall acceptability significantly decreased over time (p$lt;0.05). The scores of the four sensory properties declined to the medium level of quality after 60 days' storage. The results suggested that the sausage samples were acceptable after 60 days' storage at 4℃. However, the shelf-life of the samples should be decided in the consideration of the growth rate of other spoilage flora coupled with the bacterial growth after 50 days' storage.

약용버섯(상황·영지) β-glucan 미세캡슐 제품을 10℃, 25℃, 40℃에서 5개월 동안 저장하며 한 달 간격으로 수분함량, 색도 및 일반세균 변화를 조사하고 식품 유통기한 설정 프로그램을 이용하여 유통기한을 예측하였다. 수분함량 변화 결과 상황버섯 β-glucan 미세캡슐은 저장기간 동안 25℃와 40℃에서는 변화가 없었으나 10℃에서는 3개월째에서 증가한 후 감소하였고, 영지버섯 β-glucan 미세캡슐은 저장기간 동안 25℃와 40℃에서 약간의 증가 및 감소가 있었으나 10℃에서는 저장 3개월째에서 초기값보다 감소한 후 증가하였다. 색도 변화는 상황버섯, 영지버섯 β-glucan 미세캡슐 모두 10℃, 25℃, 40℃에서 저장 5개월째까지 큰 차이를 나타내지 않았다. 일반세균은 상황버섯, 영지버섯 β-glucan 미세캡슐의 저장기간 및 저장온도에 따른 큰 변화 없이 초기값을 유지하였다. 이들 결과를 바탕으로 상황버섯 β-glucan 미세캡슐은 30.11개월이었고, 영지버섯 β-glucan 미세캡슐은 24.82개월의 유통기한을 최종적으로 산출하였다. 따라서 약용버섯(상황·영지) β-glucan 미세캡슐 제품의 유통기한을 각각 24개월로 설정하는 것이 바람직할 것으로 사료된다.

We have studied the technology to extend the storage period of ‘Seolhyang’ strawberries using modified atmosphere package (MAP) and ethyl pyruvate (EP) treatment for domestic distribution and export. The selected ripe strawberries harvested on December 28, 2016 at the Sancheong farmhouse were transported to the laboratory for 2 h and tested. After a day’s precooling at 4℃, the strawberries were divided into seven experimental groups. These groups were control, active MAP using low density polyethylene (LDPE), active MAP using polyamide (PA), active MAP using PA with EP treatment, passive MAP using LDPE, passive MAP using PA and passive MAP using PA with EP treatment. Quality analysis was carried out every 4 days during the storage period of 16 days. During the storage period of 16 days, MAP decreased from 3.5% to less than 1.1% in weight loss ratio compared with control, and decreased from 36% to less than 7% in fungal incidence. In the case of fungi in the EP treatment group, hyphae did not grow on the outside of the strawberry but grew to the inside. This tendency was similar to that in the low oxygen and high carbon dioxide environment of the MAP, the mycelium of the fungus did not grow outside of the strawberry. Fungi are the biggest problem in the distribution and export of strawberries, and these results suggest that MAP alone could inhibit mold and increase shelf life.

Effects of high pressure processing on physicochemical and microorganisms properties in birch sap were investigated using variable high pressure processing conditions. The viable cell counts of untreated birch sap was 4.0 log CFU, whereas high pressure processed sap were not detected. In birch sap was treated with 450 to 550 MPa, microorganisms were not detected during storage period, and physicochemical properties as well as color were slightly changed. The more processing time and pressure, its quality variations were more stable and then its optimum processing condition was determined with 120 sec at 550 MPa. The microorganisms and physicochemical properties of treated birch sap were investigated during storage at 5℃ and 10℃ for 45 and 28 days. Changes of physicochemical properties of treated birch sap were smaller than those of the untreated, but viable cell count were not detected during storage period. As for pH, °Brix, and turbidity result of birch sap, quality shelf life of control and treatment were 4 and 24 days, respectively. Especially, ΔE value of instrumental color was untreated birch sap 4 days similar with the high pressure processed it for 28 days. These results indicated that the high pressure processing can be used as an effective method to improve the shelf life of birch sap.

Potato greening determines the shelf life and affects the marketability of this tuber. Various stresses during handling and storage interact to affect the tuber’s physiological status and can affect the rate of greening. This study investigated the effects of storage temperature on tuber greening and shelf life in unwashed and washed potatoes of the cultivar Superior. Physiological and biochemical changes were examined during 15 days at room temperature (23±2°C) under cool-white fluorescent light after storage for 1 month at different temperatures (4°C, 20°C). Hunter a values were negative (-) for washed potatoes after 3 days (-0.8) and 15 days (-2.5) at room temperature following 1 month of storage at 4°C while positive (+) values were observed for unwashed potatoes after 15 days at room temperature. The Hunter ΔE values of washed potatoes previously stored at 4°C for 1 month increased after 3 days at room temperature compared with those of unwashed potatoes. The total chlorophyll content of washed potatoes was higher than that of unwashed potatoes. The highest correlation was observed between the Hunter ΔE value and Hunter a value (-0.93506), while a positive correlation coefficient (0.89806) was observed between greening criteria and Hunter ΔE value by using colorimetry. We conclude, therefore, that there is a biosynthetic link between temperature-induced chlorophyll accumulation and tuber greening in storage.

The quality and shelf life of sliced root of Platycodon grandiflorum (Doraji) treated by ozon-microbubble-heat shock (OMH) were investigated by combining modified-atmosphere packaging [MAP, (50% O2+15% CO2+35% N2)]. The study was based on microbiological (total viable bacteria, fungi, Enterobacteriaceae and coliforms numbers), physicochemical and sensory changes. OMH treatment was effective in reducing microbial populations of the sliced Doraji, especially Enterobacteriaceae and coliforms reduced by 2 log CFU/g. However OMH-MAP treatment remained the aerobe and fungi numbers. Regarding the color, OMH-MAP delayed the change of Hunter b* and the sliced Doraji by OMH-MAP treatment exhibited lower decrease of flavor and overall acceptability compared to those by polypropylene packaging after tap water treatment (Control). The OMH and 50%O2+15%CO2 MAP treatment gave better sensory quality and extended shelf-life for sliced Doraji (~3 days longer shelf-life than Control). Flavor was significantly related to overall acceptability at both Control and OMH-MAP, whereas total coliforms prevalence was associated with overall acceptability at only OMH-MAP. Therefore microbubble-heat shock treatment may improve microbial safety and sliced Doraji by OMH treatment can stored under 50%O2+15%CO2 treatment for up to 7 days. Thus, OMH and MAP treatment may be used in maintaining the storage quality and marketability of sliced Doraji.

본 연구에서는 기능성 부여와 저장성이 증진된 국수를 개발하고자 양파분말을 국수에 첨가(0, 3, 5, 10%)한 후 품질특성과 저장성을 조사하였다. 양파 생면의 수분은 양 파분말 첨가량의 증가에 따른 차이는 없었으나 pH는 감소 하였다. 양파 생면의 조리 후 중량과 부피, 수분흡수율은 대조구와 양파분말 첨가군 간에 차이가 없었다. 색의 경우 생면은 양파분말 첨가량이 증가할수록 L값과 a값은 감소하 고 b값은 증가하였으나 조리면은 큰 차이를 나타내지 않았 다. 생면의 총 폴리페놀 함량과 DPPH radical 소거능은 양파 분말 첨가량이 증가함에 따라 증가하였으며 조리후에는 함량이 전체적으로 감소하였으나 생면과 동일한 경향을 나타내었다. 양파 조리면의 조직감의 경우, 경도와 씹힘성 은 대조구가 양파 첨가군에 비해 높게 나타났으나 탄력성은 대조구와 양파분말 첨가군 간에 차이가 없었다. 생면을 1 0℃에서 12일간 저장하면서 총균수를 측정한 결과 양파분 말 첨가군은 대조구에 비하여 저장성이 최소 6일 이상 연장 될 수 있었으며 그 중 양파분말 5% 첨가구가 가장 효과적인 것으로 간주되었다. 양파 조리면의 관능검사 결과 외관, 맛, 냄새, 조직감 및 전체적인 기호도는 대조구와 양말분말 첨가군 간에 차이가 없었다. 따라서 본 연구결과로 볼 때 양파분말을 국수에 5% 첨가함으로서 기능성 부여와 저장 성이 증진된 국수를 개발할 수 있으리라 생각된다.

식용 귀뚜라미를 고압증기멸균한 뒤 동결건조하였으며, 이를 분쇄하여 AL/PET/LLDPE film에 포장 후 25, 35 및 40℃에서 6개월 동안 저장하며 한 달 간격으로 품질변화를 측정하였다. 수분함량은 저장기간 중 모든 구에서 증가하 였으나, 저장 6개월 차에 저장온도별 유의적 차이는 없었다. 산가의 초기값은 1.83 mg KOH/g 이였으며, 저장 6개월 차에 25, 35 및 40℃ 저장구는 1.93, 2.04 및 2.15 mg KOH/g 으로 증가하였다. 지방산은 palmitic acid, oleic acid 및 linoleic acid가 24.79, 28.58 및 28.55 g/100 g으로 높은 함량 을 나타내었으며, palmitic acid 및 linoleic acid는 저장온도 별 증·감소의 경향이 뚜렷하지 않았으나, oleic acid는 저장 기간 중 감소하는 경향을 나타내었다. 일반세균 및 대장균 군은 저장기간 동안 검출되지 않았다. 관능검사의 경우 25 및 35℃ 저장구는 유의적 차이가 없으나, 40℃ 저장구는 유의적 차이를 나타내었다(p<0.05). 저장기간 중 품질에 영 향을 미치는 인자는 수분함량, 산가, oleic acid 및 flavor로 판단되었으며, 이들의 한계 기준을 각각 5%, 3 mg KOH/g, 26.5 g/100 g 및 6으로 설정하여 유통온도 25℃를 기준으로 VSLSF 프로그램으로 유통기한을 산출하였다. 수분함량, 산가, oleic acid 및 flavor의 유통기한을 산출한 결과 23, 61, 150 및 155개월이었으며, 유통기한이 가장 짧은 항목에 안전계수 0.8을 적용하여 18개월로 설정하였다. 이상의 결 과는 제조 후 25℃ 유통조건에서 18개월까지는 귀뚜라미 분말의 품질 안정성이 유지되는 것으로 판단되었다.

팽이버섯은 타 작물에 비해 수확 후 호흡률이 높아 갈변, 경도감소, 부패 등이 수확 즉시 진행되는 작물이다. 이러한 팽이버섯을 장기간 유통하기 위해 가장 많이 적용되는 방법은 진공 포장하여 저온 저장하는 것이다. 본 연구에서는 팽이버섯의 포장 후 유통기간을 연장에 더욱 적합한 진공필름을 선발하기 위해 20μm두께의 PE+PP, OPP 및 LDPE 필름으로 진공 포장하여 유통온도인 10℃의 저온에서 2주간 저장하였다. 일반적으로 많이 적용되는 LDPE 필름이 갈변, 줄기신장, 호흡률 급변, 조직 연화와 같은 변질이 포장 후 7일 이내로 가장 빠르게 진행되었다. 또한 OPP 필름보다 PE+PP가 수일 더 일찍 해체되기 시작하여 갈변 현상이 먼저 발생하였다. 최종적으로 OPP 필름이 안정된 호흡률과 외부색도, 신장억제 현상이 유지되어 LDPE 필름 포장군의 저장 7일차에 발생된 부패율보다 7일이 지연된 저장 14일차에 나타났다.

The aim of this study was to investigate the growth of aerobic bacteria in fresh-cut salad during short-term temperature abuse (4∼30℃temperature for 1, 2, and 3 h) for 72 h and to develop predictive models for the growth of total viable cells (TVC) based on Predictive food microbiology (PFM). The tool that was used, Pathogen Modeling program (PMP 7.0), predicts the growth of Aeromonas hydrophila (broth Culture, aerobic) at pH 5.6, NaCl 2.5%, and sodium nitrite 150 ppm for 72 h. Linear models through linear regression analysis; DMFit program were created based on the results obtained at 5, 10, 20, and 30℃ for 72 h (r2 >0.9). Secondary models for the growth rate and lag time, as a function of storage temperature, were developed using the polynomial model. The initial contamination level of fresh-cut salad was 5.6 log CFU/mL of TVC during 72 h storage, and the growth rate of TVC was shown to be 0.020∼1.083 CFU/mL/h (r2 >0.9). Also, the growth tendency of TVC was similar to that of PMP (grow rate: 0.017∼0.235 CFU/mL/h; r2=0.994∼1.000). The predicted shelf life with PMP was 24.1∼626.5 h, and the estimated shelf life of the fresh-cut salads with short-term temperature abuse was 15.6∼31.1 h. The predicted shelf life was more than two times the observed one. This result indicates a ‘fail safe’ model. It can be taken to a ludicrous extreme by adopting a model that always predicts that a pathogenic microorganism will grow even under conditions so strict as to be actually impossible.

버들송이의 기존품종의 단점을 보완하고 품종 다양화를 위해 단포자 교잡에 의해 육성된 ‘상강’의 주요 특성은 다음과 같다. 균사 생장적온은 26~28℃, 버섯 발생 및 생육온도는 18~20℃이며, 미송톱밥+밀기울+쌀겨+건비지(70:10:10:10, v/v) 배지에서 병재배 시, 배양온도 22~23℃에서 배양일수는 38일, 발이 및 생육온도 18~20℃에서 발이일수는 7일, 자실체생육일수는 5일로, 재배일수는 50일이 되어 ‘미황’과 같았다. 자실체는 개체

어수리의 실용적인 활용방법을 모색하기 위하여 어수리 분말을 첨가하여 생면을 제조하고. 이들 면의 품질특성과 저장성을 비교 검토하였다. 어수리 분말의 첨가량이 증가 할수록 국수의 중량, 부피 및 수분흡수율이 감소하였다. 어수리 분말의 첨가량이 증가할수록 국수 국물의 탁도와 조리중 고형분 손실량이 대조구에 비해 낮았다. 어수리 분말 첨가에 의해 생면의 명도(L)와 적색도(a)는 감소하였으며, 황색도(b)는 증가하였다. 어수리 분말 첨가에 의해 국수의

본 연구는 싱싱회를 , , 에서 15일 동안 보관하면서 3일 간격으로 pH, 총균수, 화학적 선도, 조직감, 관능평가를 살펴보고자 하였다. pH는 저장 직전 각각 6.25이였으며 냉장저장 시 시간이 경과할수록 점차 증가하였다. 냉동보관에서는 6일째까지 pH의 변화가 거의 없었고 저장 12일째에는 에서 6.48, 에서 6.55로 다소 증가하였다. 총균수는 냉장저장은 3일째 이후부터 이상 증가하였고, 냉동저장은 경과시간, 저장온도에 상관 없이 평

큰느타리 버섯의 polyethylene film(PE) 포장 저장성에 미치는 감압예냉(VP) 효과를 조사하였다. VP는 에서 품온이 가 될 때까지 40분간 행하였으며, 1 kg씩 PE포장하여 에서 30일간 저장하였다. 저장 중 중량감소율은 예냉처리구에서 다소 낮았다. 저장 4일째까지의 예냉구 포장내 농도는 2.44-14.50 % /kg-package/hr로 대조구의 2.01-8.19 %/kg-package/hr보다 현저하게 높았으며 저장 4일째

본 연구에서는 사용이 증가되고 있는 천공포장재 필름을 방울 토마토 저장에 이용하여 방울 토마토의 품질변화를 조사하였으며, 또한 세척 및 꼭지 제거의 최소가공 처리유무가 방울 토마토의 저장성에 미치는 영향 및 최적 천공포장 조건을 살펴보았다. 에틸렌 가스 및 이산화탄소는 천공필름 중 투과성이 가장 낮은 LF05 및 OPP/PE 필름구에서 상대적으로 투과성이 높은 LF10, LF20, LF40에 비해 높은 값을 보였고, 산소 분압의 경우 LF05에서