• Food Science and Preservation
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• v.19 no.3
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• pp.368-375
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• 2012

To decrease the intake of animal fat and cholesterol, the changes in the physicochemical characteristics of beef loin cooked through different methods (boiling, steaming, baking, and frying) were investigated. The cooking weight loss, moisture drain rate, and cholesterol drain rate were highest during frying, whereas the lipid drain rate was highest during boiling. The pH value increased markedly during steaming, the acid value of meat fat increased remarkedly during boiling, and the refractive index of meat fat increased notably upon frying. The hardness of meat was remarkedly increased by steaming. The gumminess and chewiness of meat were notably increased by frying. The springiness slightly decreased during all the cooking methods, and the cohesiveness was not significantly affected by any cooking process. The CIE $L^*$ (lightness) value increased markedly during boiling, the CIE $a^*$ (redness) value decreased markedly during both boiling and steaming, and the CIE $b^*$ (yellowness) value decreased notably during all the cooking methods. The fatty acid composition did not significantly change after cooking, except when the meat was fried. Therefore, boiling is an effective cooking method for beef loin to decrease the intake of animal fat.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2004.10a
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• pp.1-29
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• 2004

본 연구에서 저알레르기 처리 공정은 Autoclaving, 가열처리, micro wave, dry heating, 초음파, 효소, 인산염, 천연효소, 가용화, 복합처리 등의 처리 공정으로 하였다. 저 allergy처리에서 allergy가 완전히 억제되는 것은 가열처리를 한 것으로 쇄양 B(추출액+가열 3분), autoclave 처리, micro파 처리, dry heating처리, 복합처리를 했을 때이다. 또한 천연효소(키위)를 침지한 후 tolergen과 같이 3분간 가열했을 때 allergy가 억제되는 것으로 나타났다. 즉 가열처리로 인한 단백질 구조 변성으로 이러한 결과를 보인 것으로 보인다. 인산염의 경우도 어느 정도 억제가 되는 것으로 보이고 있다. 나머지 처리들은 거의 효과를 보이고 있지 않다. 천연효소와 tolergen(쇄양)을 그냥 처리했을 때에는 allergy 억제효과는 없는 것으로 나타났다. 우유의 저 allergy 처리는 효소, autoclave, micro 파, NaOH 처리, 복합처리에서 감소되는 것으로 나타났다. 이러한 결과는 western blotting으로도 확인되었으며 그 억제율 %은 식육에서는 상당한 가열처리를 통하여 알레르기를 감소시킬 수 있는 것을 볼 수 있으며 또한 인산염, 가용화(NaOH처리)도 저 알레르기 효과가 있음을 알 수 있다. 키위, 쇄양 단독 처리 시 저 알레르기 효과가 없지만 약간의 가열을 통하여 알레르기가 감소됨을 알 수 있다. 우유는 효소나 autoclave 처리만이 저 allergy 효과가 각각 28%, 45%로 적게 나타났다. 모든 복합처리의 경우에서는 그 억제율이 41-96%로 높은 효과가 있음을 알 수 있다. 천연효소처리와 인산염 처리된 식육의 전자현미경적 관찰은 control과 비교시 조직의 변화가 없고 둘다 근육 단백질 구조를 분산시키는 것으로 나타났다. 또한 고기를 단계별 복합처리로 저 allergy 처리는 단계별로 점차적으로 allergy가 감소되었다. 즉 단계별로 억제가 안되는 것부터 억제되는 처리를 복합적으로 처리한 것으로 그 단계는 천연효소처리에 인산염 처리, 여기에 초음파 처리, 마지막 단계로 3분 끓이면 억제율이 68%까지 억제되었다. 이는 단일처리시 전혀 억제를 못하는 처리를 단계별로 한 단계씩 더해가면 allergy 억제효과가 나타난다고 할 수 있겠다. 초음파 처리도 역시 저 allergy 처리 공정에 이용될 수 있는데 이것은 그 처리로 인해 새로운 알러젠이 생성될 수도 있다. 또한 복합처리로 allergy를 감소시키면 연속적이고 동시적으로 하기 때문에 원가를 절감할 수 있다.

• Korean Journal of Food Science and Technology
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• v.23 no.4
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• pp.459-464
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• 1991

The mackerel meat was packed in square No 3B can, and thermally processed at $121.1^{\circ}C$ to reach Fo values of 5, 10 and 15. On heating at $121.1^{\circ}C$, pH and volatile basic nitrogen content increased markedly, and histamine was detected at concentrations of 3.98 mg/100g in raw meat, 10.45 mg/100g in Fo 5 sample, 7.54 mg/100g in Fo 15 sample, respectively. Total free amino acid content of mackerel meat decreased with increasing Fo values. Little changes were observed in free amino acid composition, but histidine decreased significantly during heat treatment. Degradation of inosine monophosphate was proceeded during preparation and thermal processing of samples, and trimethylamine oxide changed to trimethylamine almost equivalently. In changes of lipid components, peroxide and carbonyl values were increased markedly during heat treatment. When the sample was heated at the Fo values of 5 or higher, content of non-polar lipid(NL) was increased while that of polar lipid(PL) was decreased, and percentages of polyenes such as 22 : 6 decreased with increasing Fo values. The decomposition of polyunsaturated fatty acids in PL were much greater than those in total lipid and NL.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.119.2-119.2
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• 2016

가열탈기체 처리하면 표면의 물 분자를 빠르게 탈리시켜 단시간에 배기하는 동시에 진공용기 재료 내부의 수소 확산속도를 가속하므로 처리 후 수소 기체방출도 현저하게 낮출 수 있다. 가열탈기체 후의 진공계에서는 물 분자는 일부만 남고 진공용기 재료 내부에서 확산 되어 나온 수소가 잔류가스의 대부분이 된다. 이러한 가열탈기체 처리의 효과에 대해서는 익히 알려져 있으나 정량적으로 예측하기는 쉽지 않았다. 본 연구에서는 가열탈기체 조건이 수소 확산에 미치는 영향에 초점을 맞추어, 진공용기의 재료 및 두께에 따라 목표 진공도에 도달하기 위한 가열탈기체 처리 온도와 시간의 최적 조합을 수치 해석적으로 계산하고 비교하였다.

• Applied Biological Chemistry
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• v.29 no.2
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• pp.148-158
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• 1986

The effects of sodium nitrite on weight loss, pH, color development, color and lipid oxidation for the cooking of longissimus pork muscle were studied. Higher cooking temperature and grinding of sample increased the extent of weight loss, but sodium nitrite lowered it. Cooking decreased pH and sodium nitrite lowered the level of decrease in pH. Sodium nitrite developed color and controlled discoloration with higher lightness. The content of malonaldehyde was generally accelerated by cooking, but was considerably reduced at higher cooking temperature and for longer cooking time. Sodium nitrite acted as an antioxidant but the antioxidant effect decreased with increasing cooking temperature and time. Cooking reduced the extent of each lipid on the whole. Phosphatidyl choline and phosphatidyl ethanolamine were the major phospholipids of pork, and their contents decreased during cooking. The major fatty acids in total lipids were oleic acid and palmitic acid. Those in phospholipids were linoleic acid ana palmitic acid. The high level of polyunsaturated fatty acids and essential fatty acids in phospholipids decreased during cooking. Sodium nitrite had an antioxidant effect on polyunsaturated fatty acids in both total lipids ana phospholipids.

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.3
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• pp.287-299
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• 1989

This research was conducted in order to investigate thermal stability and nutritional value of corn lipids and proteins during thermal processing. The lipids of raw and popped corn were fractionated and analyzed by column and gas chromatography. The effect of thermal processing on corn proteins was examined by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and amino acid analysis. There was no remarkable change in proximate compositions during thermal processing. The lipid fractions obtained by silicic acid column chromatography were composed of neutral lipid(93.5%), glycolipid(3.8%), and phospholipid(2.7%), Although the thermal processing showed the increase in the ratio of unsaturated/saturated fatty acid, there was no significant differences in the lipid composition between raw and popped corn. Most of each protein fractions had lower molecular weight than 25,000 dalton and albumin fractions were distributed in the molecular weight range 11,500-94,000 daltons. Popped corn proteins did not show marked differences in their electrophoretic migrations when compared with raw corn proteins.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.5
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• pp.848-853
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• 2001

This research was conducted to study the effects on antigenicities (allergenicity) and structural changes of gamma-irradiated hen’s egg albumin (ovalbumin, OVA) by heating. Three groups of OVA solution (2.0 mg/mL) were prepared; 1) heat treatment; 2) irradiation after heating; 3) heating after irradiation. Samples were isothermally heated and/or irradiated at the absorption dose of 10 kGy. Competitive indirect ELISA was individually formatted with egg-allergic patients IgE (P-IgE), and mouse murine monoclonal IgG (M-IgG) and rabbit polyclonal IgG (R-IgG) for evaluating bindinhg abilities of antibodies to OVA in the sample solutions. Binding abilities of antibodies to thermally denatured OVA were changed : R-IgG to the sample treated with above 6$0^{\circ}C$, M-IgG to that above 7$0^{\circ}C$, and P-IgE to that above 8$0^{\circ}C$, respectively. P-IgE did not well recognize OVA heated at 8$0^{\circ}C$ and the above. However, binding abilities of M-IgG and R-IgG highly in creased. Significant differences of binding abilities were not observed in all samples with the combination of heat treatment and irradiation, regardless the order of the treatment. Turbidity of samples in creased both by heating and by irradiation, and the increase by irradiation was much higher than by heating. These results showed that allergenicity of OVA reduced by gamma irradiation was not affected by heating.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.8
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• pp.1102-1105
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• 2006

The effect of heat treatments on in vitro starch hydrolysis of proso millet, sorghum, Job's tears, and buckwheat by pancreatic ${\alpha}-amylase$ was investigated. Grain samples were tested raw, boiled in water, or steamed/roasted. Starch content of the grains varied from 59.5% in Job's tears to 65.5% in proso millet, and amylose content varied from 5.3% in Job's tears to 36.3% in buckwheat. The in vitro starch hydrolysis of raw and heat-treated grains continuously increased during 60 min of hydrolysis. The starch hydrolysis (%) of raw grains after 60 min incubation was in the order of buckwheat (5.7%), proso millet (33.0%), Job's tears (51.2%), and sorghum (57.6%). Grains treated with steaming/roasting appeared to have higher starch hydrolysis rates than those with boiling except proso millet. Hydrolysis rates of buckwheat with a high amylose content appeared to be lower, compared to proso millet, sorghum, and Job's tears containing low amylose contents.

• Korean Journal of Food Science and Technology
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• v.50 no.1
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• pp.21-27
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• 2018

Turmeric oleoresin, extracted from the rhizome of Curcuma longa L., is a widely-used natural food colorant. Curcuminoids, the major pigments in turmeric, which include curcumin, demethoxycurcumin (DMC), and bisdemethoxycurcumin (BMC), possess various physiological activities. In the present study, changes in the chemical properties, antioxidant activities, and cytotoxicity of turmeric pigments upon heating were investigated. Color intensity of turmeric was significantly reduced after heating. Residual levels of curcumin, DMC, and BMC after 15 min of heating at $95^{\circ}C$ were 11.9, 37.4, and 77.3% respectively. Scavenging activities of turmeric against 2,2'-azobis-3-ethyl-benz-thiazoline-6-sulfonic acid (ABTS), 2,2-azobis (2-amidinopropane) hydrochloride (AAPH) peroxyl radicals, and nitrite were significantly enhanced after heating, while 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging activity remained unaffected. Generation of $H_2O_2$ from turmeric was increased via thermal decomposition. Cytotoxicity of turmeric pigments against colon cancer and normal intestinal cells was reduced significantly after heating. The results indicate that thermal processing affects chemical properties and bioactivities of turmeric pigments. These effects should be considered during the processing of foods containing turmeric pigments.

• Korean Journal of Food Science and Technology
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• v.52 no.6
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• pp.616-621
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• 2020

Sinapinic acid is a widely-distributed phenolic acid in various edible plants. In this study, changes in chemical stability and biological activities of sinapinic acid by heat treatment were evaluated at different pH values. The decomposition of sinapinic acid with heating at 95℃ was accelerated at higher pH; the residual levels after 10 min of heating were 80, 45 and 24% at pH 6, 7 and 8, respectively. Levels of reactive oxygen species derived from sinapinic acid also increased after heating at pH 7 and 8. ABTS radical scavenging activities and ferric reducing antioxidant power of sinapinic acid were reduced significantly after heating at pH 7 and 8. The cytotoxic activity of sinapinic acid against HCT116 cells was significantly enhanced after heating at pH 8 with decreased glutathione levels. The results suggest that heat treatment causes changes in the chemical stability and biological activities of sinapinic acid, and such changes are more prominent at higher pH.