The freezing process of the freeze-drying procedure is important to optimize the physic-chemical properties of agricultural product. Therefore, our study was carried out to study the effect of freezing methods on the properties of freeze-dried apples. The sliced apples was frozen at -18°C as a general refrigerator (GR), -30°C with a individual quick freezing machine (IQF), and -80°C with deep freezer (DF), and subsequently, each sample was sublimated under 0.1 mbar for 24 hours. The samples were characterized by determination of color, texture properties, sugar contents, and morphology observation. The quality of color (L*, a* and b*) did not show significant discoloration. The hardness and sugar contents of IQF samples showed the greater value than GR and DF one. The morphology of IQF samples displayed the uniform and relatively small pore size as compared to GR and DF samples. From the sensory test, the IQF samples obtained the high score for overall acceptability, and consumer preference. From our results, the IQF treated apples are best results to produce good quality of freeze-dried apples.

In this study, we investigated the effects of different pre-treatment conditions such as blanching and drying process to improve its quality. Bracken samples were treated by drying (70°C for 40 min), blanching (100°C for 2 min) or mixed (blanched and dried [BD]), respectively. These treated samples were analyzed for their physicochemical properties such as pH, color and microbial growth. The pH of bracken increased from 6.6 to above 6.9 through all treatment. From color observation, the L* and b* values increased after drying process, whereas, the a* values decreased. Water contents of bracken decreased by about 80% from 93% through drying process. After samples treated by pre-treatments, hardness increased, especially after drying process. For the microbial study, raw bracken had 5.6 log CFU/g of aerobic bacteria and 2.8 log CFU/g of total coliform. Blanched and BD samples had about 2 log CFU/g of aerobic bacteria and 1.8 log CFU/g of total coliform, acceptable for food. From our results, it is concluded that the properties of blanched samples had similar to raw samples to guarantee for microbial safety. From the obtained results, the blanching process without drying process is necessary to apply freezing process as pretreatments.

The reduction of the content of sodium chloride in noodle was studied to prevent the problems related to excessive sodium intake, such as high blood pressure and cardiovascular diseases. This study investigated the effect of hydrolyzed anchovy products (HAP) on the salty taste of cooked noodle. The experiment was set up to determine the general properties of dough in dried and cooked noodles, with a sensory test used while increasing the concentration of HAP at same salt contents. There was no significant difference in water binding capacity, solubility, swelling power, lightness, and cooking properties. The redness, yellowness, and hardness were increased upon increasing the contents of HAP. From the sensory evaluation, cooked noodle with added HAP had a high score in appearance, color, texture, and flavor. Moreover, 50% and 75% HAP showed higher values than the control item in saltiness, preference of saltiness, and overall acceptance. Consequently, the HAP could have an effect on dried noodles or cooked noodles as a salty taste enhancer without changing the noodle’s properties.

In the food industry, freezing storage has been an important process for maintaining the properties of food materials. In order to maintain the quality of blanched Colocasia esculenta (L.), Schott stem, packaging, freezing, and thawing methods were optimized by determinations of the physicochemical properties. For the comparison of packaging method, Colocasia esculenta (L.) Schott stem packed by air containment had the lowest significant differences of properties such as hardness and drip loss compared to the control samples. Overall, the drip loss of Colocasia esculenta (L.) Schott stem had lower value at fast freezing rate (immersion freezing). Considering the result of the drip loss, high frequency thawing was more effective than other thawing methods. Therefore, it was supposed that samples treated by air-containing packaging, immersion freezing, and high frequency thawing used the optimal method to maintain the original quality of Colocasia esculenta (L.) Schott stem.

Food freezing preservation is an important process due to its high quality and long shelf-life. In order to improve the quality of frozen sweet potato stem, the freezing rate, thawing, and packaging method was optimized by the determination of physical properties. There was no significant difference among the treatment of freezing rate. Further, the drip loss of sweet potato stem was higher at a relatively fast freezing rate (immersion freezing) than at slow freezing rate (natural convection freezing at -20 or -40oC). For the comparison of packaging methods, the aircontaining packaged sweet potato stem had the lowest significant differences from the result of color, pH, and hardness. From the result of the drip loss, the high frequency and microwave using thawing samples were more effective than room temperature and water thawing. Therefore, fast freezing and thawing rate with air-containing package were recommended to obtain the better quality of sweet potato stem.

This study was carried out to investigate the effect of liposome-coated salt (LCS) on the salty taste intensity of noodle. Dough, dried noodle, and boiled noodle with LCS were evaluated physico-chemically for water content, water binding capacity, solubility, swelling power, color, texture, cooking properties, and sensory test. There were no significant differences in water content, water binding capacity, lightness, yellowness, and texture of noodle between the noodles with liposome-coated salt and non-coated salt. For the sensory analysis, the panel did detect more salty taste at 1.0% and 2.0% of LCS compared to the control. From these results, this study demonstrates that liposome coated salt can enhance salty taste, maintaining the same salt concentration without the physical property changes of noodle.

There are a lot of types of wild vegetables such as Colocasia esculenta (L.) Schott stem in Korea. However, the consumption of these wild vegetables is restricted because their storage decreased dramatically after harvest. To maintain original quality of vegetables, pre-treatments such as blanching and drying are important. But conditions for these treatments were still not optimized for many vegetables including Colocasia esculenta (L.) Schott stem. Thus, the objective of this study was to set up an optimal pre-treatment method for freezing storage. Colocasia esculenta (L.) Schott stems were peeled and cut equally (10 cm) for sample preparation. Dried samples (D) were dried at 90℃ for 3 h. Blanched samples (B) were blanched in hot water at 100℃ for 2 min. Blanched and dried samples (BD) were blanched and dried as same protocol. Physicochemical properties were analyzed to evaluate the quality including texture, moisture content, total color difference and viable cell count. Raw sample had 6.85 kg/cm 3 of hardness and 78.75 of chewiness whereas B was 6.83 kg/cm 3 of hardness and 7.8 of chewiness. B had the similar value compared to raw samples. Moisture content of raw sample was 94.4% and that of B was 94.1%, though there were not any significant differences between them. ΔE value of B showed lower value than those of the others. Viable cell counts and total coliforms were not detected after treatment, while raw sample had 5.39 log CFU/g of viable cell count without total coliform. Therefore, pre-treatments are essential for microbial safety of samples. All results considered, it is supposed that blanching is the optimal pre-treatment to sustain its original quality of Colocasia esculenta (L.) Schott stems before freezing.

The overconsumption of dietary salt is recognized to play a negative effect on human health such as increasing blood pressure. The purpose of this study is to investigate the effect of hydrolyzed anchovy products (HAP) on the salty taste of dried noodle. The physicochemical properties and sensory test of dried noodle were determined at different concentrations of HAP. The lightness of the noodle samples was decreased with increasing levels of HAP whereas their redness and yellowness were increased. There were no significant changes in hardness and texture properties by HAP concentration, compared to those of the control. From the sensory evaluation, the 25% and 50% HAP samples showed a high score on saltiness, preferredness, and overall taste acceptability. Consequently, the HAP could be utilized in dried noodles or cooked noodles as a salt enhancer without significantly altering the charateristics of noodles.

To investigate the preference of food of the elderly for developing processed elderly food, this study was conducted from February 2014 to March 2014 by questionnaire including dietary behaviors, food preference, and frequency of food intake to 119 elderly (49 males and 70 female) who were more than 65 years old and living in Jeonju. Most subjects ate three meals regularly and most of the subjects’ favorite meal time was lunch. The duration time of one meal was 20 min (48.74%). The most preferred taste was delicate and sweet. The subject preferred cooked rice with multi-grains, kalguksu (hot noodle), and abalone porridge to other staple foods. Almost 50% of the subjects liked soybean paste soup and stew, and the ratio of elderly who liked Chinese cabbage kimchi was 72.3%. Preference for panfried foods leaned toward pan fried fish fillet and mung bean pancake. Most subjects preferred plant foods like vegetables, lettuce, and seaweeds. The elderly in Jeonju liked roasted pork, grilled yellow croaker, and stir-fried octopus. Cooked and seasoned vegetables (namul) were the most preferred type by the elderly. Preferences for dishes and food materials were not affected by sex and ages. Most subjects preferred eating out with Korean food. Preference for eating food was selected in grilled beef ribs, a pork cutlet, sushi·broiled eels, and Chinese noodles. Western Japanese and Chinese food were preferred by an elderly subject, who was male and who liked Japanese food more than female.

The objective is to investigate effect of liposome coated hemicellulose on softening of carrot. To encapsulate hemicellulose in nanoliposome, 2% hemicellulase and 2% lecithin were processed by using high-speed homogenizer (10,000 rpm, 3 min) and ultrasonification (200 W, 54%). The carrot were cut into cylinder type (3×1 cm) and then immersed in distilled water (DW, control), hemicellulase (He) and nanoliposome coated hemicellulose (He/NL) for 48 h at 4oC. The final concentration of hemicellulose is 1% (w/v). The droplets properties of He, NL, He/NL analyzed using zeta-sizer. Moreover, the carrots treated different immersed solutions were characterized by measuring hardness, color, microstructural observation and enzyme activity (glucose contents). For the results, hardness of carrot immersed in He or He/NL solution decreased after 48 h by 47% or 31% (outline of carrot) and 35% or 31% (center of carrot) respectively compared to control (7,240 g). The total color difference value of all samples increased over immersion time. For microstructural observation, cell was destroyed after 24 h at He solution. For the enzyme activity, glucose contents of carrot in He solution increased than it in He/NL at 0 h sample however the enzyme activity was no significant difference with immersion time.

본 연구에서는 다양한 냉동기법인 자연냉동 및 강제송풍 식냉동, 극저온냉동과 다양한 해동방법인 자연해동, 유수해 동, 초음파해동, 전자레인지해동을 통하여 물리적 변화를 최소화 하는 냉·해동공정을 찾으려 했다. 당근의 경우 품 질을 변화 시키는 요인은 해동방법보다는 냉동방법이 더 영향력이 있다. 해동감량 및 보수력의 변화를 관찰한 결과 급속냉동(강제송풍식냉동, 극저온냉동)을 한 경우 품질유지 에 더 효과적이었다. 경도는 냉·해동공정 보다는 블랜칭 처리를 한 것이(열처리) 유의적으로 품질이 저하되는 것을 관찰하였다. 즉 열처리가 당근의 물성에 영향을 더 미치는 것으로 판단된다. 색도 및 pH 경우, 냉·해동공정에 의해 크게 영향을 받지 않는 것으로 나타났다. 당근의 전체적인 품질을 최대한 유지 하기 위해서는 냉동법의 고려가 해동 법 보다 중요하며, 다양한 냉동방법 중 급속냉동처리하는 것이 효과적인 것으로 판단되며, 유지하고자 하는 당근 품 질 특성 별로 최적의 냉·해동공정을 선정하는 것도 효과적 이라 생각한다

Blanching and freezing of beef are important techniques used in developing frozen home meal replacement (HMR) products. These pre-thermal treatments minimize the deterioration of beef during storage. Beefs are washed, defatted, sliced (5.0×0.5×0.5 cm, fiber direction), and blanched by immersion in hot water for 2 min. Thereafter, the blanched beefs are spin-dried and frozen by individual quick freezing (IQF) method. Finally, the frozen beefs are packed using two methods: vacuum packages and air-containing packages. Packed beefs are stored at -12oC, -18oC, and -24oC for nine months. One in every three months, they are thawed in a microwave (400W). While thawing, vacuum-packed samples possess lower thawing loss than air-containing-packed ones. Compared to raw beef, blanched beef have a higher L* and lower a* value. However, less changes are observed after blanching the beefs as the enzymes get inactivated in the blanching process. Shear force of beef also increase through blanching. Moreover, vacuum-packed samples have maintained their hardness to a greater extent than the air-containing-packed samples. All the samples have met microbial safety standards. Thus, it is inferred that vacuum-packaging and -18oC storage temperatures are the best condition for maintaining beef that is later developed into HMR product.

The pre-treatment conditions of butterbur stem such as blanching, freezing, and thawing were studied to optimize it for producing frozen butterbur stem to improve its storage ability. Butterbur stems were hot water blanched at 100oC for 3, 5, or 7 min respectively and then soaked in cold water. After peeling out and cutting into blocks (4.5×1.0×0.5 cm), butterbur stems were air-dried for 5, 10, or 15 min respectively. Dried samples were analyzed for their physicochemical properties. With blanching, the hardness value increased from 2.91 kg to 3.64 kg (p>0.05); however, adhesiveness decreased drastically after 5 min of blanching (p<0.05), which changed to a crisp texture. In addition, considering other physicochemical properties, it was assumed that 5-min blanching was optimal pre-treatment to maintain the original quality of butterbur stem for freezing. Five-minute blanched butterbur stems were airdried 5 min, frozen and thawed with several methods, and analyzed for their properties. Considering the thawing loss, hardness, and color change, the fastest freezing and thawing method had the lowest changes on the quality of frozen butterbur stem. Therefore, to produce frozen butterbur stem, it was assumed that immersion freezing and running water or room temperature thawing (25oC) were the best process.

본 연구는 다양한 냉동방법(강제송풍식냉동, 극저온냉동, 일반냉동)과 해동방법(자연해동, 유수해동, 초음파해동, 전자레인지해동)을 조합하여 처리했을 때 표고버섯의 물리적 품질에 미치는 영향을 관찰하고, 표고버섯의 품질을 유지하는 가장 효과적인 냉·해동 공정을 탐색하는 것이 목적이었다. 급속냉동법(강제송풍식냉동, 극저온냉동)으로 처리한 경우 표고버섯의 해동감량, 보수력, 수분함량은 큰 변화 없이 품질을 유지 하는데 효과적인 것으로 관찰되었다. 특히 보수력은 저속냉동(일반냉동) 및 저속해동(자연해동) 처리의 유무가 영향을 미치는 것으로 나타났다. 전단력의 경우 냉동방법에 의한 영향보다, 전처리 및 해동방법에 더 영향을 받는 것을 판단된다. pH 및 색도는 냉동방법 및 해동방법에 따라 거의 차이가 없는 것으로 관찰되었다. 표고버섯의 물리적 특성을 효과적으로 유지 할 수 있는 처리 조합은 급속냉동(극저온냉동) 및 급속해동(유수해동, 초음파해동, 전자레인지해동)을 한 경우이며, 또한 유지하고 하는 물리적 특성에 따라 냉동 및 해동방법을 다양하게 조합하여 처리한다면, 식품의 품질을 보존하는데 더욱 효과적일 것으로 사료된다.

본 연구는 열수침지 및 과열증기 처리한 당근을 IQF 방 법으로 급속 냉동 한 다음 -12, -18, -24 o C에서 24주 동안 저장한 후 해동하여 이화학적 및 영양학적 특성과 미생물 학적 변화를 분석하여 열처리 및 냉동 저장의 최적 공정 과정을 확립하고자 하였다. 대체적으로 과열증기 처리한 당근보다 열수침지 처리한 당근의 ΔE이 큰 값을 나타내었 고, 열처리 후 생당근에 비해 전단력이 감소하였으나 급속 냉동 후 저장 기간에 따른 유의적인 차이를 나타내지 않았 다(p>0.05). 열처리 후 생당근에 비해 총균수가 감소되었지 만 냉동 저장시 일정한 경향을 보였고, 열수침지 처리한 당근의 비타민 C 손실양이 과열증기 처리한 당근보다 더 많았다. 열수침지 처리 후 감소한 유리당의 함량은 저장 기간에 따른 변화는 없던 반면, 과열증기 처리 후 급속 냉 동 한 당근의 유리당 함량은 증가하였다. 당근의 유기산의 함량은 열수침지 처리 후 감소하였으나 과열 침지 처리 후 oxalic acid와 malic acid 함량은 증가하는 경향을 보였다. 이를 통해 열처리 후 영양 성분의 손실이 더 적은 과열증 기법의 공정 과정이 열수침지법보다 더 적절한 것으로 보 인다. 또한 -12 o C에서 저장한 당근의 비타민 C가 6개월 후 모두 파괴되었던 것을 통해 비타민 C의 파괴를 최소화하 기 위해서는 이보다 더 낮은 온도에서 냉동 저장해야 할 것이라 사료된다.

본 연구는 양파를 열처리 법 중에서 열수침지, 증기 및볶음 처리에 따른 이화학적 및 영양학적 특성을 분석한 논문으로 열처리가 양파에 미치는 영향을 비교하고자 하였다.상품을 구매할 때 1차적인 구매요소인 색도 및 경도측정과 추가적으로 pH와 조직관찰 결과로 최적조건 선정 후영양학적 및 미생물 검사를 실시하였다. 열처리를 하지 않은 대조구에 비해 짧은 시간의 열처리에서는 더 진하고 선명한 색을 띠었으나, 장시간동안 처리한 열처리 시료는 색의 침착을 보였다. 원물과 처리구의 색은 열처리 시간에따라 뚜렷한 차이를 나타냈고, 경도는 열처리 시간에 따라짧은 시간에서는 분해효소의 불활성화로 유지 및 증가했지만, 3분 이상 처리하였을 때는 감소 경향을 나타냈고, 볶음처리는 짧은 시간으로도 물성이 연화됐다. 비타민은 열수 및 증기처리 1~2분 처리는 14% 정도 감소했지만 그이상 처리 시에는 23~28% 범위로 큰 감소율을 보였으며,유리당 및 유기산의 경우 열수침지 및 증기처리에서 손실을 보였지만, 볶음처리에서는 유지하거나 증가하는 경향을나타냈다. 특히 유리당에서 열수침지 처리 시 높은 감소율을 나타냈다. Peroxidase activity 변화는 모든 처리구에서75% 이상의 불활성화를 나타냈고, 특히 열수침지 및 증기처리한 모든 시료에서 90% 이상의 불활성화를 나타내며볶음처리보다 높은 불활성화율을 보였다. 미생물 측정한결과 열수 침지 3분 이상 및 볶음처리 210초 이상 처리시 미생물 검출이 안됐으며, 증기처리 시료는 2분 처리만으로 사멸된 것을 관찰했다. 양파의 열처리 조건은 증기처리법으로 2분 동안 처리하는 것이 다른 처리법에서 처리한 시간들에 비해 최적으로 나타났다. 열처리 방법 별 각각의 최적 처리 시간을 가지고 있어, 높은 효율성이나 산업적으로 이용하려면 최적의 전처리 방법과 처리 시간을산정하는 것이 중요하다.

본 연구는 최적의 냉해동 조건을 확립하고 설정된 조건에 따라 냉해동이 당근에 미치는 이화학적 분석 및 영양성분의 분석을 진행하였다. 본 실험에서는 강제송풍방식을이용하였으며, 자연대류식(0.2oC/min), 저속(0.4oC/min) 및고속(1.6oC/min)으로 냉동속도를 조절하여 -12oC까지 냉동하였다. 해동조건은 전자레인지를 이용하여 0, 200, 400,800W의 세기로 출력을 조절하여 시료의 중심부 온도가4oC가 될 때까지 해동하여 분석에 사용하였다. 당근의 강도는 냉해동 후 유의적으로 감소하는 경향을 보였으며, 특히 200, 400W 해동 시 냉동 속도가 빠를수록 감소하였다.해동감량의 경우 해동방법에 따른 유의적인 차이는 없었지만 냉동속도가 높을수록 감소하는 경향을 보였다. pH 및색도의 데치기 후 당근과 처리구간의 유의적인 차이는 보이지 않았다. 그러나 전자 현미경 관찰 결과, 냉동속도가빨라질수록 기공의 크기가 작아지는 것을 확인할 수 있었으며 이는 빠른 냉동속도가 식품 조직의 손상을 막는데 영향을 미친다는 것으로 보인다. 비타민 C 및 유기산(oxalicacid, malic acid 및 fumaric acid) 함량의 경우 유의적인차이는 나타나지 않았다. 유리당 함량의 경우에는 sucrose함량은 자연대류 냉동 시 가장 높았고, fructose 및 glucose의 함량은 유의적인 차이가 없었다. 본 연구 결과 냉해동방법에 따른 영양학적 변화는 대부분 데치기 후 당근과 유사하였으나, 당근을 고속으로 냉동할 시 물리적 변화 및조직 손상을 최소화 하였으므로 당근의 품질을 유지하는데효과적인 것으로 판단된다.

염료감응형 태양전지에 사용되기 위한 유기/무기 복합소재를 합성하였다. 다양한 분자량(600, 1,500, 2,000, 3,400)의 polyethylene glycol 양 끝단을 ethoxysilane기로 치환하여 전구체를 제조하였으며, 전구체간의 졸-겔 반응을 통하여 복합소재를 합성하였다. 전해질막은 유기/무기 복합소재를 KI 및 I2로 도핑하여 제조하였으며, 제조한 전해질의 이온전도도 특성을 측정하였다. 전해질막의 이온전도도는 원료로 사용한 PEG에 크게 영향을 받았으며 가장 높은 이온전도도는 분자량 2,000의 PEG를 사용한 전해질막에서 볼 수 있었다. 복합전해질막은 이온전도도에 있어서 큰 향상을 보였다. PEO 전해질막에 비하여 분자량 2,000의 PEG를 사용하여 제조한 복합전해질막은 월등하게 높은 이온전도도를 보였다.

염료감응형 태양전지에 사용되기 위한 유기/무기 복합소재를 합성하였다. 다양한 분자량(400, 600, 1,500, 3,400)의 polyethylene glycol의 양 끝단을 ethoxysilane기로 치환하여 전구체를 제조하였으며, 전구체의 졸-겔 반응을 통하여 복합소재를 합성하였다. 전해질막은 유기/무기 복합소재를 NaI 및 I2로 도핑하여 제조하였으며, 제조한 전해질막의 이온전도 특성을 측정하였다. 전해질막의 이온전도도는 원료로 사용한 PEG에 크게 영향을 받았으며 가장 높은 이온전도도는 분자량 1,500의 PEG를 원료로 사용한 전해질 막에서 볼 수 있었다. 복합전해질막은 전도도에 있어서 큰 향상을 보였다. PEO 전해질막에 비하여 분자량 1,500의 PEC로 제조한 복합전해질막은 월등하게 높은 이온전도도를 보였다.