본 연구에서는 국내에서 흔히 음용하고 있는 물이 동결 후에 발생될 수 있는 흰 침전물은 무엇이고, 물속에 녹아 있는 이온들의 변화는 얼마나 일어나는 지 알아 보았다. 그 결과는 아래와 같다. 1. 흰 침전물의 EDS 분석결과, Si가 주성분인 것으로 나타났다. 2. 침전량과 해동 전후에 변화된 Si농도를 비교하여 본 결과, 질량의 차이가 상당히 났기 때문에 침전량을 SiO_2로 환산하여 계산해 본 결과, 변화된 Si 농도와 환산된 침전량이 거의 일치하였다. 그러므로 흰 침전물은 SiO_2로 판단된다. 3. 국내에서 흔히 음용되고 있는 칼슘이 적은 물(30㎎/l 이하)에서 생기는 흰 침전물은 Si가 주성분이었고, 수원의 특성에 따라, 즉 칼슘이나 황산이온이 다량 함유된 경우에는 흰 침전물이 칼슘, 규소, 황상이온 등으로 구성된 침전물이 발생할 수 있다. 4. Si 농도와 침전량은 거의 비례하였으며, Si가 많은 지하수(먹는샘물, 약수)에는 침전물이 많이 발생한 반면, 상대적으로 Si 농도가 적은 수돗물에는 침전물이 거의 발생하지 않았다. 5. 국내에서 흔히 음용되고 있는 물은 Si를 제외한 다른 이온들은 침전물 발생에 거의 영향을 미치지 않으며, 농도 변화도 없었다. 하지만, 칼슘이나 황산이온이 다량 함유된 물의 경우에는 침전물 발생에 영향을 주며, 칼슘이온 등의 농도 변화가 있었다.

This study was conducted to determine the desirable thawing method and storage time of Nokchaborijook(gruel made of barley, rice powder and Green tea) which made of optimum conditions as the 5.8% Green tea and 15 seconds grinding time. Decision on desirable storage time(10, 20, 30, 40, 50days), thawing method(water bath, microwave oven) of frozen Nokchaborijook were determined by sensory evaluation and physicochemical attributes. As the storage time became longer, moisture and flavonoid contents were decreased. Viscosity, the ratio of water seperation, spreadability of Nokchaborijook which stored at 30 days showed great differences between the two thawing method. Among the sensory characteristics, desirability for overall, flavor, and texture were decreased as the storage time became longer. As a result of consumer test, Nokchaborijook thawed at water bath was more desirable than Nokchaborijook thawed at microwave oven. According to the results, frozen Nokchaborijook can be using as a supplement of dietary fiber and flavonoid for the health and be using convenience food.

This experiment was carried out to investigate the effects of osmolarity of thawing diluents, seminal plasma added in thawing diluents on the sperm viability and the effects of thawing temperature, the temparature of the thawing diluents on the sperm viability and acrosomal morphology of boar spermatozoa by the straw method. The result obtained were summarized as follows: 1. The sperm viablilty after thawing of the frozen semen was shown greater in the high osmolarity(392~492mOsm) than low osmolarity(300mOsm) in thawing diluent. The added levels of seminal plasma in thawing diluent did not affect the viability of frozen-thawed boar semen. 2. In terms of thawing temperature, the sperm viability was shown higher in the frozen semen thawed at 5 for one min. (p<0.01) than those thawed at 2 or 37 for one min. The sperm viability was not significant at the diluent temparature of 2or 37 after thawing: but the sperm viability was higher in thawing diluent at 2 than in that at 37. However, the effects of thawing temperature and diluent solution on normal acrosomal rate were not significant. 3. Cleavage rates of oocytes fertilized with frozen semen were 46.4% and 43.3%, respectively, which were thawed at 5 for one min. and then diluted in mBTS medium at 2or 37. To sum up, the sperm viability was shown greater at the high of thawing diluents of frozen boar semen. In terms of thawing conditions, the sperm viability was shown greater, when semen was thawed at a high temperature for a short time and then diluted at the same temperature as that in the straw.

This study were carried out to investigate the effective concentration of cryoprotective agents and sucrose by one-step straw method, and to determine the optimum thawing temperature and equilibration time of frozen porcine embryos. The porcine embryos foflowing dehydration by cryoprotective agents and a various concentration of sucrose were directly plunged into liquid nitrogen and thawed in 3 water. Survival rate was defined by FDA test. The results are sunnnarized as follows : 1. The survival rates of porcine embryos after ultrarapid frozen4hawing in the freezing medium with a various concentration of glycerol, DMSO and propanediol added 0.25M sucrose were higher survival rate than those of sucrose concentration of 0.50M. 2. The survival rates of porcine embryos after ultrarapid ftozen4hawing in the freezing medium added 0.25M and 0.SOM sucrose were higher survival rate than those of sucrose concentration of 0.75M and 1.00M. 3. The temperature thawed at 2 and 3 resulted in a significantly higher embryos survival rate after 72 hrs in culture than did at 35. 4. The equilibration time on the survival rate of porcine embryos was attained after short period of time(2.5~5 min.) in the freezing medium higher than long period of time(10~20 min.).

The objective of this experiment was to study some possibilities to simplify freezing, thawing and transfer procedure of one-step straw method comparing with the conventional methods using bovine embryos. The previous work are also designed to investigate the thawing effect by development stage and its quality using the embryos. Results obtained were summarized as follows: 1. A total of 87 embryos from 14 donor cows were frozen-thawed and an average of frozen embryo/donor was 6.2. 2. The survival rates of morula stage(65.4%) were higher than those of blastocyst stage(57.l%) and vice versa in rate of morphological recovery (80% vs 95.4%). However. no significant difference was denoted between them. 3. In difference between the groups of good quality and poor quality. good quality was resulted in a significantly higher embryo survival rate(75%) and recovery rates(95%) than poor quality(P<0.0l). 4. In effects of non-permeable sugar dilution in added to l.0M glycerol. higher survival rates were orderd in sucrose. lactose, raffinose and xylose. But lactose-raffinose, sucrose-trehalose and xylose in added to 2.OM glycerol. 5. The highest survival rates were obtained by direct plunge into the liquid nitrogen with 3.OM concentration both of glycerol and trehalose. 6. The survival rates in vitro condition of one-step and direct plunge methods(75%-87.5%) were significantly higher than those of multiple steps (21.4-52.6%) in in vitro (P<0.0l). However, the results of single-step were critical in comparing to other steps of final pregnant conformation.