• 제목/요약/키워드: Heat treatment milk

Search Result 111, Processing Time 0.027 seconds

Determination of ${\alpha}-lactalbumin$ in Heated Milks by HPLC (HPLC에 의한 열처리된 우유중 ${\alpha}-lactalbumin$의 정량)

  • Kee, Hae-Jin;Hong, Youn-Ho
    • Korean Journal of Food Science and Technology
    • /
    • v.24 no.4
    • /
    • pp.393-395
    • /
    • 1992
  • The ${\alpha}-lactalbumin({\alpha}-la)$ concentration in raw and laboratory-heated milks by HPLC was 1.20 mg/ml (unheated), 1.17 mg/ml ($63^{\circ}C$, 30min), 1.13 mg/ml ($72^{\circ}C$, 15sec) and 0 mg/ml ($100^{\circ}C$, 10min), respectively. Whereas, ${\alpha}-lactalbumin$ concentration ranges of commercial milks were $1.00{\sim}1.02\;mg/ml$ (pasteurized), $0.23{\sim}0.68\;mg/ml$ (UHT-pasteurized) and $0.77{\sim}0.89\;mg/ml$ (UHT-sterilized), respectively. It was supposed that the ${\alpha}-lactalbumin$ content of sterilized milk will be lower than that of UHT milk, but the opposite occurred. This discrepancy would be caused by the different heating system in the milk plants, where indirect UHT-treatment had more heat intensity than direct UHT-processing. The HPLC determination of ${\alpha}-lactalbumin$ may be an indicator to evaluate correctly and rapidly heated milks.

  • PDF

Research Trends and Future Directions for R&D Vitalization of Domestic Dairy Industry (국내 유가공산업의 R&D활성화를 위한 연구 동향과 방향)

  • Yoon, Sung-Sik
    • Journal of Dairy Science and Biotechnology
    • /
    • v.29 no.1
    • /
    • pp.23-31
    • /
    • 2011
  • Domestic dairy industry is now standing at the crossroad for planning next fifty years, mainly because economic and environmental situations surrounding Korean peninsula are fast changing. For the aspects of dairy consumption, fresh milk consumed less, while consumption of the other milk and dairy products is slightly increasing every year. In 2010, it is approximately estimated that 1,939,000 tons of raw milk was used and the supply would be short by about 35,000 tons, based on the amounts in the previous year. Currently, multilateral negotiations against US and EU are underway. When it will be in effect in the future, significant damage would be expected in the dairy and livestock sectors, leading to cut domestic milk supply. Quality of farm-gate milk is graded as 1A on average 90% or more, loaded with very low in microbial and somatic cell counts. Therefore, policy implications have to be placed toward switch currently the UHT processing method to Pasteurization or the LTLT technology, by which natural flavors and nutrients in milk mostly remain after heat treatment. Domestic cheese products comprise only 10% and the rest is occupied by the various kinds of imported natural products. The market size keeps increasing up to 65,423,000 tons last year. When it comes to vitalization of our natural cheese industry, cheese whey, which is a main by-product in cheese manufacture, is a critical issue to be solved and also "On-Farm Processing" would be combined with a growth of big dairy companies when few immediate issues among the relevant regulations will be eased and alleviated in the near future. Fermented milk market is recorded as a single area of gradual increase in the past 10 years, Korea. Fermented yogurts with health claims targeted stomach, liver, and intestine are popular and has grown fast in sales amounts. In this context, researches on beneficial probiotic lactic acid bacteria are one of the important projects for domestic milk and dairy industries. Labelling regulations on efficacy or health-promoting effects of functional dairy products, which is the most important issue facing domestic dairy processors, should be urgently examined toward commercial expression of the functionality by lawful means. Colostrum, a nutrition-rich yellowish fluid, is roaded with immune, growth and tissue repair factors. Bovine colostrum, a raw material for immune milk preparations and infant formula, can be used to treat or prevent infections of the gastrointestinal tract. Nanotechnology can be applied to develop new milk and dairy products such as micro-encapsulated lactase milk for consumers suffering lactose intolerance. Raw milk is suggested to be managed by its usage in the processing line because imbalance of supply and demand is structural problem in every country and thus the usage systems as in the advanced dairy countries is worth of bench-marking to stabilize milk supply and demand. Raw milk produced is desirable to divide into the three parts; domestic, import, and buffering purposes. It is strongly recommended that a domestic dairy control center as an institutional framework should be urgently established as is Dairy Board in New Zealand and Australia. Lastly, government policy should be directed to foster the highly-educated people who are majoring in Dairy Sciences or working in the dairy industry by means of financial support in studying and training abroad as well.

  • PDF

Changes in Lactic Acid Bacteria and Physicochemical Properties of Yogurt Made with High Pressure Processing Treated Milk (고압처리 원유로 제조한 발효유의 저장 중 유산균 수 변화와 이화학적 특성)

  • Ahn, Sung-Il;Chung, In-Ae;Chung, Woon-Si;Jhoo, Jin-Woo;Kim, Gur-Yoo;Jeon, Jung-Tae
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.45 no.6
    • /
    • pp.889-893
    • /
    • 2016
  • This study was carried out to investigate the physicochemical and fermentation properties of yogurt made from high pressure processing (HPP) treated milk. Raw milk and commercial yogurt starter were used to make yogurt. Raw milk was HPP treated at 350 or 450 MPa (HPP 350 or 450) for 15 min or heat treated at $80^{\circ}C$ for 10 min. The numbers of lactic acid bacteria of the HPP treated group (HPP yogurt) rapidly increased during 2~4 h, whereas there was not significant difference from control (P<0.05). Titratable acidity of all samples increased, and pH decreased during storage from 0.99 to 1.24%, as well as from 4.59 to 4.20, respectively. It is confirmed that these values are in general ranges for yogurt. Control showed higher viscosity than HPP 350. Syneresis was significantly lower than that of the control (P<0.05). Based on the data obtained from the present study, HPP treatment was effective to enhance the quality of yogurt.

Functional Properties of Soy Protein Isolates Prepared from Defatted Soybean Meal (탈지대두박(脫脂大豆粕)에서 추출(抽出)한 분리대두단백(分離大豆蛋白)의 식품학적(食品學的) 성질(性質))

  • Byun, Si-Myung;Kim, Chul-Jin
    • Korean Journal of Food Science and Technology
    • /
    • v.9 no.2
    • /
    • pp.123-130
    • /
    • 1977
  • A laboratory study was made to develop a simple and economic model method for the systematic determination of functional properties of 'Soy Protein Isolates (SPI)' prepared from defatted soybean meal. These are required to evaluate and to predict how SPI may behave in specific systems and such proteins can be used to simulate or replace conventional proteins. Data concerning the effects of pH, salt concentration, temperature, and protein concentration on the functional properties which include solubility, heat denaturation, gel forming capacity, emulsifying capacity, and foaming capacity are presented. The results are as follows: 1) The yield of SPI from defatted soybean meal increased to 83.9 % as the soybean meal was extracted with 0.02 N NaOH. 2) The suitable viscocity of a dope solution for spinning fiber was found to be 60 Poises by using syringe needle (0.3 mm) with 15 % SPI in 0.6 % NaOH. 3) Heat caused thickening and gelation in concentration of 8 % with a temperature threshold of $70^{\circ}C$. At $8{\sim}12\;%$ protein concentration, gel was formed within $10{\sim}30\;min$ at $70{\sim}100\;^{\circ}C$. It was, however, disrupted rapidly at $125\;^{\circ}C$ of overheat treatment. The gel was firm, resilient and self-supporting at protein concentration of 14 % and less susceptible to disruption of overheating. 4) The emulsifying capacity (EC) of SPI was correlated positively to the solubility of protein at ${\mu}=0$. At pH of the isoelectric point of SPI (pH 4.6), EC increased as concentration of sodium chloride increased. Using model system$(mixing\;speed:\;12,000\;r.p.m.,\;oil\;addition\;rate:\;0.9\;ml/sec,\;and\;temperature\;:\;20{\pm}1\;^{\circ}C)$, the maximum EC of SPI was found to be 47.2 ml of oil/100 mg protein, at the condition of pH 8.7 and ${\mu}=0.6$. The milk casein had greater EC than SPI at lower ionic strength while the EC of SPI was the same as milk casein at higher ionic strength. 5) The shaking test was used in determining the foam-ability of proteins. Progressively increasing SPI concentration up to 5 % indicated that the maximum protein concentration for foaming capacity was 2 %. Sucrose reduced foam expansion slightly but enhanced foam stability. The results of comparing milk casein and egg albumin were that foaming properties of SPI were the same as egg albumin, and better than milk casein, particularly in foam stability.

  • PDF

Contents of Nitrogen Fractions and the Degree of Whey Protein Denaturation in Market Milks (시유의 질소분획물 함량과 유청단백질 변성정도)

  • 박영희;홍윤호
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.22 no.2
    • /
    • pp.161-164
    • /
    • 1993
  • To find out the effective indicators for identification and classification of different heat treatment, the contents of nitrogen fractions and the degrees of whey protein denaturation in market milks were investigated by Kjeldahl method. The contents of nitrogen fractions per 100ml raw milk were total nitrogen (431.3mg), casein nitrogen (341.0mg) and non-casein nitrogen(90.3mg), in which non-protein nitrogen (31.6mg) and denatured whey protein nitrogen (58.8mg), while those of LTLT, HTST, UHT pasteurized and UHT sterilized showed different values. The degrees of whey protein denaturation were 26.7%(LTLT), 32.9%(HTST), 60.7%(UHT pasteurized) and 38.4%(UHT sterilized), respectively. As the higher temperature was applied for the treatment of milk, the degree of the whey protein denaturation was higher. Remarkable differences in the degree of whey protein denaturation according to the heating methods were observed.

  • PDF

Effect of Feeding Systems on Feed Intake, Eating Behavior, Growth, Reproductive Performance and Parasitic Infestation of Black Bengal Goat

  • Moniruzzaman, M.;Hashem, M.A.;Akhter, S.;Hossain, M.M.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.15 no.10
    • /
    • pp.1453-1457
    • /
    • 2002
  • The experiment was conducted to find out the effect of 4 feeding systems on growth, feed intake, eating behavior, lactation performance, gestation period, post-partum heat period, conception rate and parasitic infestation of Black Bengal goat. Twenty four does of approximately 1 year of age were randomly selected for 4 treatment (feeding systems) groups having 6 replications in each. Treatments were stall feeding ($T_1$), tethering ($T_2$), restricted grazing ($T_3$) and grazing ($T_4$). $T_1$ group was housed continuously and adequate amounts of natural grass were supplied for ad libitum feeding. $T_2$ group was tethered for grazing natural grass from 8 a.m. to 4 p.m. being moved at one hour intervals. Goats of $T_3$ group were allowed grazing from 8 a.m. to 1 p.m. $T_4$ group was grazed from 8 a. m. to 4 p.m. Concentrate supplement was given at the rate of 150 g per day per goat for all of the treatment groups. Duration of experiment was 219 days. Daily live weight gain was significantly (p<0.05) higher in case of stall fed goats than that of others. DM intake also significantly (p<0.05) differed among the treatment groups and was 3.40 3.95, 3.76 and 4.05 per cent of their live weight for stall feeding, tethering, restricted grazing and grazing groups, respectively. Rate of rumination was significantly (p<0.05) higher in case of tethering group of goats than that of others. Birth weight of kids, milk yield, lactation period and post-partum heat period were significantly higher in case of stall fed goats than others. Tethering group showed significantly (p<0.05) higher litter size than others. Infestation rate of Fasciola was significantly (p<0.05) higher in the grazing group. In conclusion, it may be stated that among these feeding groups overall performance of stall fed goats was more satisfactory, and that the tethering group showed better performance than the others.

Effect of Rainwater Sprinkling System Utilization for Reducing Heat Stress in Milking Cows during Intense Heat Time (폭염시 착유우 고온스트레스 경감을 위한 빗물관수시스템 이용 효과)

  • Choi, Dong-Yoon;Cho, Sung-Back;Park, Kyu-Hyun;Yang, Seong-Hak;Hwang, Ok-Hwa;Kwag, Jung-Hoon;Jeong, Kwang-Hwa;Song, Jun-Ik;Yoo, Yong-Hee;Ahn, Hee-Kwon
    • Journal of Animal Environmental Science
    • /
    • v.18 no.sup
    • /
    • pp.21-28
    • /
    • 2012
  • Since the temperature during summer is higher than the temperature which is suitable for milking cows, high temperature stress have severely affected dairy farmers due to decreased milk production. This study was carried out to investigate the effect of rainwater sprinkling system for reducing heat stress in milking cows during intense heat time. Treatment conditions were divided into 2 types ; No rainwater sprinkling (T1) and Rainwater sprinkling (T2). Temperature in the milking cow shed, feed intake, milk yield, respiration rate and rectal temperature were measured to investigate the effect of hot environment on the physiological, productive responses in milkig cows. The results obtained are summarized as follows : The daily milk yields were 24.5 and 27.4 kg per head in T1 and T2 during experimental period. The respiration rate was significantly higher in T1 than those of T2. The rectal temperature in T1 ($40.6^{\circ}C$) was higher than those of T2 ($39.8^{\circ}C$). It was suggested that rainwater sprinkling system installed in the dairy cow shed was effective means to reduce heat stress of milking cow.

Stability of Protein Colloids in the Mixture of Cheese Whey and Soy Milk (유청(乳淸) 및 두유(豆乳) 혼합액에서의 단백질 콜로이드 안정성)

  • Shon, Dong-Hwa;Lee, Hyong-Joo
    • Applied Biological Chemistry
    • /
    • v.29 no.1
    • /
    • pp.83-89
    • /
    • 1986
  • To investigate effectors on the colloidal stability of whey and soybean proteins, characteristics of tofu-gel formation, effects of heat treatment and salt composition on the colloidal stability, and effects of heat treatment on storage stability were analyzed. When experimental tofus were made from the mixture of whey and soybean, the calcium in the whey precipitated the soy proteins, and disrupted the gel formation, which resulted in the curd of poor texture. In the heat treatment at $60{\sim}100^{\circ}C$, whey and the whey proteins dialyzed against distilled water were readily preciptated at over $70^{\circ}C$, but the mixture of whey and soy extract as well as soy extract were stable at the range of temperature. The proteins of soy extract, whey dialyzed against sodium phosphate buffer, and the mixture were stable at the same heat treatment, and this suggested that phosphates in the soy extract stabilize specialty the whey proteins. Soy proteins were easily destabilized by adding $CaCl_2(0.05{\sim}0.07M)$ at $80{\circ}C$ and $70{\sim}85%$ of the proteins in soy extract and the mixture were preciptated, while only $30{\sim}55%$ of the proteins in whey dialyzed against distilled water were destabilized at the same conditions. Storage stability at $4^{\circ}C$ of the mixture was increased when the mixture was treated at $63^{\circ}C$ and lower temperature.

  • PDF

Oriental Medical Approach on the Allergic Disease (알레르기성 질환에 대한 한의학적 접근)

  • Im Gwang Mo;Jeong Hyun Woo;Kim Hee Sung;Jeong Woo Yeal
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.16 no.5
    • /
    • pp.831-839
    • /
    • 2002
  • Allergy has a born predominant cause of atopy in body and react oversenstively several meterial. The cause of allergy are tick, house dust, egg, milk, bean, cosmetics, virus, bacteria, flesh and meat in Western medicine. While, Oriental medicine did not have an application on the allergy, but recognized that allergy is connected with fetal toxicosis, heat-syndrome in new born, syndrome characterized by dyspnea, sneezing, stuffy nose, nasal discharge and phlegm. Therefor, We knowed method of medical treatment following cause of disease and pathogenesis against allergy. Allergic disease(atopic dermatitis, bronchial asthma, rhinitis) were related with lung, spleen, kidney. To prevent allergic disease in born, Oriental medicine taked a serious view of fetal education. In Western medicine, The cause of allergy applied to exopathogen of Oriental medicine. In Oriental medicine, Treatment of allergy used generally strengthening the body resistance to eliminate pathogenic factors.