• 한국식품과학회지
• /
• 제20권6호
• /
• pp.762-768
• /
• 1988

우유의 지방분해 효소인 리파제를 분리 연구하기 위하여 홀몬처리 되지 않은 정상유와 홀몬 처리된 비정상유에서 리파제를 Heparin-Sepharose-CL-6B를 이용하여 분리 정제하였다. Heparin-Sepharose에 친화력을 조사한 결과 두 개의 효소활성이 있는 성분이 구분되었으며 한 성분은 Heparin-Sepharose-CL-6B에 결합되었고 다른 한 성분은 결합되지 않은 채 분리되었다. 친화성 크로마토그램에 결합되어 분리 정제된 리파제의 최적 온도, 최적 pH, 기질 특이성, 분자량 및 BSA의 활성제로서의 작용등 여러 가지 효소특성은 모두 동일한 것으로 나타났다. 그러나 홀몬처리된 소에서 얻은 우유의 경우에는 또 다른 호소활성 성분이 나타나 있음을 알았다. 이 lipolytic activity가 있는 성분은 Heparin-Sepharose-CL-6B에 친화력을 보이지 않았으므로 정상적인 milk lipase와는 구별된다. 따라서 홀몬처리된 소에서 얻은 우유에 함유된 성분중 Heparin-Sepharose에 결합된 효소는 유지방 자동산화에 영향을 끼치지 않으며 Heparin-Sepharose에 결합되자 않은 활성이 있는 성분은 자동산패에 영향을 크게 미친다고 볼 수 있다. 그 이유는 hormone의 불균형 상태로 인하여 생유에 자동산패가 일어날 수 있으며 이것은 비정상적으로 분비된 리파제 출현 사이에 연관관계가 있음을 의미한다.

• 한국식품과학회지
• /
• 제23권1호
• /
• pp.6-14
• /
• 1991

골격근의 longissimus dorsi근(white muscle) 및 soleus근(red muscle)과 심장근(cardiac muscle)의 근섬유간 지질의 산패량과 각종 영향인자의 첨가효과를 비교하였다. 얻어진 결과는 다음과 같다. 지질의 산패량은 white muscle>red muscle>cardiac muscle의 순이었으나, 지질함량으로 보정된 산패량에는 white muscle과 red muscle사이에 차이가 없으며, 따라서 지질 산패량은 근육의 지질함량에만 지배받는 것으로 나타났다. 미오글로빈은 근섬유의 산패에 대하여 현저한 촉진작용을 나타내었으나, 근섬유의 함량차이(white muscle 1%, red muscle 5%)에 의한 차이는 관찰되지 않았다. 산패 억제기능의 아질산염과 산패 촉진기능의 식염이 적정량 함유된 건조 육제품이 진공포장된 경우 지질 산패량은 전 유통기간에 걸쳐 품질저하의 주요원인이 되지 않았다.

• 한국식품조리과학회지
• /
• 제13권5호
• /
• pp.609-616
• /
• 1997

한국 대표적인 기호식품의 하나인 약과를 저장시 지방의 산패정도와 물성을 평가하였다. 15$0^{\circ}C$에서 8분 동안 튀겨서 10분간 집청한 약과를 표준시료로 하여 분석한 결과 지방은 24.4%로 매우 높은편이었다. \circled1저장시 수분함량은 시럽집청한 약과가 9.9~10.8% 로서 집청하지 않은 구에 비해 약 4%정도 높았다 \circled2 0, 5, 10, 15, 20, 30일간 상온저장하면서 측정한 산가, TBA가, 카보닐가는 저장초기에 비해 저장 30일에는 각각 2배, 1.3배, 1.4배로 증가하엿다. \circled3 집청은 산패의 진행을 방지하는 효과를 보였고, 생강즙첨가시는 다소 낮은 산가, TBA가, 카보닐가를 나타내어 집청과 생강즙의 첨가는 약과 저장시의 지질산패 억제에 효과가 있었다. \circled4색도의 L값은 집청구가 집청하지 않은 구에 비해 낮았고 저장함에 따라 감소하였으며, a, b값은 집청하지 않은 구가 다소 높았다. \circled5저장시의 rheometer 측정에서는 생강즙을 넣고 시럽에 집청한 약과가 다른 실험구에 비해 elasticity와 chewiness가 다소 감소하였으나, 저장기간이나 생강즙 첨가유무는 질감에 영향을 미치지 못하였고 집청이 큰 요인이었다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제19권3호
• /
• pp.450-458
• /
• 2006

The present study was carried out to investigate the changes in chemical and sensory properties, and cholesterol lowering effect of evening primrose oil (EPO) addition in cholesterol-reduced Cheddar cheese. The cholesterol removal rate reached 92.07% by ${\beta}$-cyclodextrin in the cheese before EPO addition. The thiobarbituric acid (TBA) value of cholesterol-reduced and EPO-added cheese increased with both ripening time and amount of EPO addition. Addition of 5% EPO resulted in a significant difference in TBA value after 4-week ripening, compared with no addition of EPO. The production of short-chain free fatty acids (FFAs) increased with ripening period in all treatments. From 4 week of ripening, the amounts of short-chain FFA in 3 and 5% EPO-added groups were significantly higher than those in other groups. Among sensory characteristics, rancidity was mostly affected by EPO addition, however, the rancidity value of 1% EPO-added was not significantly different from that of EPO-free and cholesterol-reduced cheese. Also, Cheddar cheese flavor was not profoundly affected by 1% EPO addition in all ripening periods. Total blood cholesterol dramatically decreased from 184.0 to 137.1 mg/dL with 5% EPO-added and cholesterol-reduced cheese following 8 weeks of feeding. The present results indicated that 5% EPO addition resulted in a profound lowering effect on blood total cholesterol with some adverse effects on chemical and sensory properties.

• 한국식품과학회지
• /
• 제25권5호
• /
• pp.517-520
• /
• 1993

돈육의 pH가 5.0에서 7.0으로 증가할수록 저장중 산패치는 유의차 있게 감소하였다. 본 실험 결과 고 pH 돈육의 낮은 유리철 함량과 높은 GPx 활성은 저장중 돈육의 산패 억제에 관여하는 중요한 요인들인 것으로 밝혀졌다. 그러나 pH 조절에 의한 산패 억제에 관여할 수 있는 그 밖의 다른 가능한 인자들을 찾는 연구 또한 중요하다고 하겠다. 나아가서 유리철 ion의 방출 억제나 불활성화 방안, GPx의 또 다른 활성화 방안 및 천연항산화제로서의 활용 가능성등이 계속 연구, 검토되어야 할 것이다. 본 연구의 결과는 돈육의 저장성 증진은 물론, 규명된 항산화 기작들을 다른 작품 system에 응용하는 데에도 이용될 수 있을 것으로 본다.

• 한국축산식품학회지
• /
• 제30권6호
• /
• pp.966-974
• /
• 2010

This study evaluated the effects of rice bran fiber (RBF) on the quality of semi-dried pork jerky (SDPJ). SDPJ was supplemented with RBF at levels of 0 (control), 1, 2, and 3%. The addition of RBF at various levels affected the composition of SDPJ except for the fat content (p>0.05). The addition of RBF at a level higher than 2% increased the protein and ash contents of SDPJ (p<0.05). The addition of RBF at various levels also affected the physiochemical properties of SDPJ (p<0.05) except for water activity (p>0.05). Increased level of RBF increased the pH. The rancidity of SDPJ was increased (p<0.05) regardless of the RBF level, whereas the metmyoglobin content (%) of SDPJ was increased at a level higher than 2%. Increased level of RBF decreased the shear force (p<0.05) and the increased processing yield of SDPJ (p<0.05). Jerky made with 2% RBF scored highest for sensory properties, including color, tenderness, juiciness, and overall acceptability (p<0.05). These results indicate that SDPJ containing 2% RBF had the most acceptable quality characteristics, but further study is required to reduce the rancidity induced by the addition of RBF.

• 한국식품조리과학회지
• /
• 제8권2호
• /
• pp.147-154
• /
• 1992

This study was carried out to investigate the rancidity of deep frying foods (cuttlefish and swetpotato) in Incheon city. The samples were collected from 3 snack corners in market, and at 10, 14 and 18 o'clock. The Acid Value, Peroxide Value and TBA value of the fried products were determined and Sensory Evaluation was also performed. The results are as follows: 1. The range of Acid Value was 0.73~1.91 on cuttlefish and 0.33~1.03 on sweetpotato. There was no significant difference in all samples by times and places. 2. The range of Peroxide Value was 3.26~8.23 on cuttlefish and 3.45~11.63 on sweetptato. There was no significant difference in all samples by times and places. 3. the range of TBA Value was 50.03~132.27 on cuttlefish and 30.63~112.83 on sweetpotato. The TBA Value of the products in department store at 18 o'clock more less than mat at 10 o'clock. 4. The Acid Value and TBA Value of sweetpotato was more less than those of cuttlefish. 5. In sensory evaluation, mere was no significant difference by times but significant difference by places on all items. 1) In greasy taste, the first one among cuttlefish products was mat of department store and last one was market product which was much more greasy taste. Among sweetpotato products, the products of department store and near-college were more less greasy man market product. 2) In flavor and overall quality, the product of department store was better than near-college and market products on all samples, 3) In color, the products of department store and near-college were more light man market products on all samples. 4) There was correlation between color and flavor, and overall quality flavor. The flavor and color of products have the effect on the overall quality of products.

• 한국식품영양과학회지
• /
• 제11권4호
• /
• pp.37-41
• /
• 1982

In order to determine the optimal condition for making Yugwa (one of the Korean traditional cake) the textures in various conditions were studied by sensory test and texturometer. The changes of texture and fat content in the cake were measured along the period of storage. The results were as follows: (1) The cake were classified in 3 groups according to the leavening agent used in the procedure, namely refined rice wine (W), distilled liquor (L) and yeast group (Y). It was the refined rice wine group that had been 'the best' by sensory test. Its brittleness $(1.40{\pm}0.27)$ was higher than those of L and Y. (2) Crispness measured by bend test prior to soaking into syrup were 1.19, 1.23 and 1.63 in W, L, Y, respectively. (3) Chemical composition (%dry basis)) of Yugwa leavened with W included 9.3 of moisture, 1.3 crude protein, 6.7 crude lipid, 66.4 carbohydrate and 16.3 crude ash. (4) Brittleness decreased gradually along the period of storage while the rancidity increased. From the 40th days of storage, the change of brittleness and rancidity were marked as well as the scores of sensory test decreased significantly. (5) Content of linoleic acid in Yugwa decreased along the period of storage from 52.5% of total fatty acid on the first day to 10.9% on the 50th days Main fatty acids in Yugwa were oleic acid, palmitic acid and stearic acid, all of which were also decreased in content along the period of storage. One remarkable change was the appearance of an unknown fatty acid with 19.54 of retention time, in 50% of total fatty acid, on the 50th day of storage.

• 한국약용작물학회지
• /
• 제25권5호
• /
• pp.296-304
• /
• 2017

Background: Sancho oil extracted from Zanthoxylum schinifolium (Siebold & Zucc) is a useful edible oil that has been in use for a long time, but it is known to be susceptible to rancidity. Sancho oil purification can remove impurities to prevent rancidity. This study was performed in order to improve the quality of sancho oil and enhance its availability throughout the purification process. Methods and Results: Sancho oil extracted in Hadong, Korea was refined via the degumming and deoxygenation processes, following which we examined the changes in the polyphenol content, fatty acid content and antioxidant activity of the oil. Acetic acid was effective for deoxygenation of sancho oil and 2 N NaOH was effective for its deoxidation. The polyphenol content and antioxidant activity were reduced by the purification process. Saturated fatty acids contents did not vary with the degumming and deoxygenation processes, however the content of unsaturated fatty acids were slightly reduced. Conclusions: This study suggests that the process of sancho oil purification used in this study will contribute to the increased use and storage of sancho oil.

• Animal Bioscience
• /
• 제35권2호
• /
• pp.290-298
• /
• 2022

Objective: This study was conducted to investigate the effects of adding oregano (Origanum syriacum L.) and germander (Teucrium polium L.) to poultry diets individually and/or in combination: i) on cooked chicken meat quality and storage stability, ii) to compare this effect with those of the synthetic antioxidant butylated hydroxyanisole (BHA) and with the normal basic diet (Control: without supplements). Methods: Broilers (140 birds) were raised for 21 days and then equally divided into five different treatment groups of 28 birds each. The dietary treatments were as follows: i) control; ii) germander (GER, 1.5%); iii) oregano (ORE, 2.5%); iv) combination of GER and ORE (CM, 1.5%, and 2.5%); v) BHA (0.02%). Meat patties from the five treatments were prepared, cooked, and stored at 4℃ prior to analysis. During storage, samples were measured for thiobarbituric acid-reactive substances (TBARS) and total carbonyl levels at 0, 4, and 7 days. In addition, cooked thigh meat was prepared separately to evaluate cooking loss and sensory attributes. Results: The CM dietary treatment showed the highest antioxidant effect, with decreasing TBARS values (breast and thigh meat) throughout the storage time (4 to 7 days). Furthermore, ORE showed a higher antioxidant effect, decreasing the rancidity development (TBARS values), compared to the GER during the storage period (days 0 to 7). The anti-carbonyl effect of the CM supplement was the highest among all treatments from day 0 to 7. Generally, the antioxidant effect of GER was lower compared to that of ORE and BHA alone. The CM treatment most significantly decreased off-odor and rancidity development, with the lowest oxidation odor scores. Conclusion: The results indicate that the combination of oregano and germander in the diet of boilers improves meat quality and prolongs shelf life.