Temperature distribution studies were performed in steam-air retort to investigate the influence of various processing conditions (come-up time, sterilization temperature, and internal pressure throughout the steam-air retort). Retort temperature data were analyzed for temperature deviations during holding phase, maximum temperature difference between test locations at the beginning and after 1, 3, and 5 min of the holding phase, and box-and-whiskers plots for each location during the holding phase. The results showed that high sterilization temperature led to a more uniform temperature distribution than low sterilization temperature (pasteurization). In pasteurization condition, the temperature stability was slightly increased by increasing pressure during the holding phase. On the other hand, the temperature stability was slightly decreased in high sterilization temperature condition. Programming of the comeup phase did not affect the temperature uniformity. In addition, the slowest cold spot was found at the bottom floor during the holding phase in all conditions. This study determined that the temperature distribution is affected by retort processing conditions, but the steam-air retort needs more validation tests for temperature stability.

The purpose of this study was to investigate the relationship between retort food characteristics and consumers’ perceptions and to survey 295 consumers from December 10 to December 20 as the center of consumers who purchase retort food. As a result, most of the consumers who purchase retort food were women and the age were under 25 and 26 to 30 years old. There were many housewives and students in the occupation group and 2 to 3 in the family members. In addition, many graduated from college and many places of purchase were convenience stores and large discount stores. Consumer retort food purchase rate were high by 30-40% in meat products. Fish meat products were high by 30-40% and sauces were high by 20-30%. Instant foods were high by 20-30%, Tang (탕) / Guk (국) / Jigae (찌개) were high by 30-40% and canned food were high by lower than 10%. As a result of the influence of retort food characteristics on positive perceptions only convenience were influential. The effects of the characteristics of retort food on negative perceptions were influenced only by hygiene and standardization.

Quality changes of carrots thermally processed in a large size (5 kg) retort pouch during 52 weeks of storage were investigated under different packaging methods and package shapes. To improve the efficiency of thermal processing (121.1oC, 0.15 MPa), the carrot (i.e., solid) and the broth (i.e., liquid) of the carrot soup were separately packed and sterilized. The quality changes of carrot packed without liquid were compared with those with liquid. Two different package shapes such as rectangular parallelepiped and cube were also evaluated to figure out the efficiency of the heat penetration rate for a large-sized pouch. The TTT (F0-values = 6) were 27, 54, and 114 min from the rectangular parallelepiped, cube, and solid/liquid mixed groups, respectively. In the mixed groups, the hardness and chewiness of solids (carrot) were significantly smaller than those measured in the other groups as TTT increased. Carrots treated in the rectangular parallelepiped shape showed a significantly higher texture than the cube shape. The CV of hardness and chewiness in the rectangular parallelepiped and the cube shape were calculated as 7.56 and 47.19, and 29.16 and 65.28, respectively. This demonstrated that a more uniform quality can be obtained from the rectangular parallelepiped shape.

Quality changes of carrots thermally processed in a large size (5 kg) retort pouch during 52 weeks of storage period were investigated upon different packaging methods and package shapes. To improve the efficiency of thermal processing (121.1°C, 0.15 MPa), the carrot (i.e., solid) and the broth (i.e., liquid) of carrot soup were separately packed and sterilized. The quality changes of carrot packed without liquid were compared with those with liquid. Two different package shapes such as rectangular parallelepiped and cube were also evaluate to figure out the efficiency of the heat penetration rate for the large size of pouch. The location of cold points and the total thermal processing time (TTT) were different upon the treatment. Fo-values, satisfying the TTT to at least 6 min, were 27, 54, and 114 min from the rectangular parallelepiped, cube and solid/liquid mixed group, respectively. In the mixed groups, the hardness and chewiness of solids (carrot) was significantly smaller than that measured in the other groups as TTT increased. Carrots treated in the rectangular parallelepiped shape showed a significantly higher texture than the cube shape for both immediately after the thermal treatment and during the storage period. Coefficient of variation (CV), which indicates the quality variation within the same treatment, of texture properties obtained from the outside and the center of the sample were compared to evaluate the quality variation within the same treatment. The CV of hardness and chewiness of the rectangular parallelepiped and the cube shape were calculated 7.56 and 47.19, and 29.16 and 65.28, respectively. This demonstrated that more uniform quality could be expected from the thermal treatment in the rectangular parallelepiped shape

The effect of temperature distribution in the retort on the degree of sterilization and the product quality was investigated. The temperature distribution in the retort chamber in an industrial scale of retort was evaluated. The target processing temperature was set to 121.1°C based on the standard sterilization process for C. botulinum. The temperature distributions at several points in the retort chamber were measured during the sterilization process, such as the heating (25°C to 121.1°C), holding (121.1°C), and cooling (121.1°C to 25°C) processes. Fo-values at different positions in the chamber were evaluated and compared. Potato cubes were used as a control sample to obtain the heat penetration curve for evaluating the degree of sterilization and the quality changes. Potato samples in cube shape (13×13×13 mm) were prepared and packed in 5 kg of retort pouch pack. A significant temperature deviation occurred during the cooling process and it significantly affected the degree of sterilization.

Quality changes of retort pouched curry sauces were studied under various sterilization and storage conditions. The retort pouched curry sauces sterilized at 110oC for 30 min and stored at 37oC showed the lowest sensory qualities among the tested samples. Meanwhile, when the sample was sterilized at 101oC for 60 min and stored at 4oC, the quality changes of the sauces were not significant during 30 days of storage. The taste sensing results of curry sauces showed that there were not a lot of changes in flavor when stored at 4oC while the sauces stored at 37oC showed increases in bitterness and sourness which eventually caused degradation of total quality. Sensory evaluation results of the samples stored at 4oC (4.3 points) and at 37oC (3.5 points) also coincided with the taste sensing results. Conclusively, it is desirable to sterilize the retort pouched curry sauce at 101oC for 60 min and to store at 4oC until consumption (if possible, within 30 days). Further, the acid value (1.01) and pH (3.88) of curry sauces were found to be used as quality change indices for references.

현재 저온유통만 허가되어 있으며 저장유통기간이 짧은 게맛어묵에 레토르트 살균기술과 반응표면분석 법을 도입하여 기존의 풍미나 품질에 손상됨 없이 상온유통과 장기저장이 가능한 게맛어묵을 제조하기 위하여 가열살균기술의 최적화 조건을 구명하였고, 본 레토르트 살균처리가 게맛어묵의 품질특성에 미치 는 영향에 대하여 검토하였다. 반응표면분석의 독립변수는 살균량 (F0-value)과 가열온도로 하였으며, 이 들의 영향을 받는 가열살균 후의 품질인자, 즉 종속변수는 전단력, 백색도 및 관능적 조직감으로 나타내 었다. 레토르트 살균이 게맛어묵의 품질 및 전반적인 식품성분의 변화에 미치는 영향을 검토한 결과, F0-value 5분 이하의 가열살균에서는 F0-value보다는 가열온도가 게맛어묵의 품질 변화에 미치는 영향 이 큰 것으로 나타났으며, F0-value 2.6분 이상으로 가열살균할 경우 게맛어묵의 무균성이 확인되었다. 반응표면분석 program으로 설정한 레토르트 게맛어묵의 최적 가열살균조건은 전단력의 경우 가열온도는 115.7℃, F0-value 3.3분, 백색도는 가열온도 116.1℃, F0-value 3.8분, 그리고 관능적 조직감의 최대화 조건은 가열온도 115.8℃, F0-value 3.3분이었고, 이 3가지 품질요소를 모두 고려한 multiple response optimization 반응조건은 가열온도 117.5℃, F0-value는 3.3분이었다.

본 연구에서는 해외 레토르트 식품의 패키지 디자인 사례를 살펴보고, 국내 레토르트 식품의 패키지 디자인의 문제점을 소비자 설문조사를 통하여 알아보고, 그 보완점을 찾아보기 위한 기초 연구로서의 의미를 갖는다. 연구의 범위는 국내 레토르트 식품 중 한국전통식품인 삼계탕과 육개장으로 한정하며, 연구 방법은 패키지 디자인 구매 척도 7가지 형용사에 대입하여 결과를 분석한다. 연구 내용은 2장에서 레토르트 식품의 이론적 배경을 살펴보았으며, 3장에서는 해외 레토르트 식품 패키지 디자인 사례를 일본과 미국을 중심으로 살펴보았고, 4장에서는 국내 레토르트 식품의 패키지 디자인 분석을 서울에서 활동하는 20대, 30대, 40대 이상의 남녀를 대상으로 설문조사하여 분석했다. 국내 레토르트 식품 구입 시 패키지 디자인에 대한 요소별 중요도를 분석한 결과 브랜드 로고 , 메인 컬러, 제품 사진, 심볼 로고, 레이아웃의 순으로 나타나 국내 삼계탕과 육개장 레토르트 식품 구매 시 제조사의 브랜드를 가장 중요하게 생각하고 있으며, 그 다음으로 제품 요리 사진을 중요하다고 나타났다. 본 연구에서는 국내 삼계탕과 육개장 레토르트 식품 패키지 디자인의 개선방안으로 첫째, 브랜드 강화, 둘째, 식품정보의 정확한 표기, 셋째, 구매시점광고(P.O.P) 패키지의 적용을 제시하였다.

본 시험은 식품의 장기간 저장이 가능하고 간편하게 유통할 수 있는 Retort pouch 기술을 찰옥수수에 접목시켜 저장 중 품질유지 및 저장비용 절감을 위하여 찰옥수수 레토르트 가공 적성을 분석한 결과는 다음과 같다. 1. 식품적성은 식품공전에 의한 저장전 레트로트 식품규격에 따른 성상 및 세균 조사결과 모든 처리에서 팽창되지 않았으며 세균검출 시험결과도 음성으로 나타났다. 2. 미생물 활성과 부패에 관여하는 수분활성도 측정결과 30일 저장후 부터 레토르트 공정전 전처 리로서 열수처리에서는 일반곰팡이 번식 조건인 0.80보다 높은 0.81~~0.87 로 나타났으며 60일 후에 낮아지는 경향이었고 증숙처리, 급속냉동처리 등에서는 일반 부패세균 및 곰팡이 번식조 건 0.80 이하로 안정성으로 나타났다. 3. 색도색차는 냉동+레토르트 처리시 타처리에 비하여 어두워 외관상 상품성이 떨어졌고 레토르트 처리시 121℃ 의 10분간은 색깔이 우수하였고 저장조건은 5℃,15℃ 보다 -20℃ 냉동저장이 다소 우수하였으나 큰 차이는 없었다. 4. 저장기간에 따른 유리당 함량은 저장조건에 따른 미량의 차이는 있었지만 뚜렷한 경향은 없었다. 5. 식미는 저장 60일부터 레토르트 공정전 무처리, 열수처리 및 급속냉동처리에서는 식미가 떨어지고, 이취가 발생하여 저장성이 떨어졌으나 증숙 처리한 옥수수는 5℃,15℃ 저장시 20℃ 에 냉동 저장된 시료와 큰 차이 없이 양호하였다.