• Asian-Australasian Journal of Animal Sciences
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• 제30권11호
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• pp.1643-1650
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• 2017

Objective: The control of psychrotrophic bacteria causing milk spoilage and illness due to toxic compounds is an important issue in the dairy industry. In South Korea, Gangwon-do province is one of the coldest terrains in which eighty percent of the area is mountainous regions, and mainly plays an important role in the agriculture and dairy industries. The purposes of this study were to analyze the indigenous microbiota of raw milk in Gangwon-do and accurately investigate a putative microbial group causing deterioration in milk quality. Methods: We collected raw milk from the bulk tank of 18 dairy farms in the Hoengseong and Pyeongchang regions of Gangwon-do. Milk components were analyzed and the number of viable bacteria was confirmed. The V3 and V4 regions of 16S rRNA gene were amplified and sequenced on an Illumina Miseq platform. Sequences were then assigned to operational taxonomic units, followed by the selection of representative sequences using the QIIME software package. Results: The milk samples from Pyeongchang were higher in fat, protein, lactose, total solid, and solid non-fat, and bacterial cell counts were observed only for the Hoengseong samples. The phylum Proteobacteria was detected most frequently in both the Hoengseong and Pyeongchang samples, followed by the phyla Firmicutes and Actinobacteria. Notably, Corynebacterium, Pediococcus, Macrococcus, and Acinetobacter were significantly different from two regions. Conclusion: Although the predominant phylum in raw milk is same, the abundances of major genera in milk samples were different between Hoengseong and Pyeongchang. We assumed that these differences are caused by regional dissimilar farming environments such as soil, forage, and dairy farming equipment so that the quality of milk raw milk from Pyeongchang is higher than that of Hoengseong. These results could provide the crucial information for identifying the microbiota in raw milk of South Korea.

• Journal of Dairy Science and Biotechnology
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• 제39권4호
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• pp.129-144
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• 2021

Following the COVID-19 pandemic, many people are increasingly becoming interested in health and environmental issues. Therefore, the sale of vegan or vegetarian products has been increasing over the last few years, as well as interest in non-dairy plant-based milk that can replace cow's milk. Furthermore, the global food industry has developed an interest in such products, considering the recent changes in consumer trends. In Korea, various products are being launched annually due to the increasing interest in non-dairy plant-based milk. However, research with regard to the quality and type of products produced in Korea is still at the preliminary stage when compared to those in the United States and Europe. Therefore, the present review has summarized non-dairy plant-based milk analogues based on the following key aspects. First, the types of non-dairy plant-based milk analogues and their production technologies (in the order of almond milk > cocoa milk > coconut milk > hemp milk > kidney bean milk > oat milk > peanut milk > rice milk, and soy milk). Second, the current status and future prospects for non-dairy plant-based milk analogues. Third, recent trends and future challenges associated with the production and quality improvement of non-dairy plant-based milk analogues. Fourth, the current status and outlook of the non-dairy plant-based milk analogue market in Korea. In conclusion, the present review could provide the food industry with valuable information regarding non-dairy plant-based milk analogues to facilitate the development of related products. Data were obtained from previously published studies.

• Journal of Biosystems Engineering
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• 제33권2호
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• pp.130-135
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• 2008

The purpose of this study was to develop a preprocessor for real-time portable quality evaluation system of milk. The preprocessor consisted of two flow pump to supply milk sample and reaction reagent at given volume, a fan to mix milk with reaction reagent, a thermoelectric device to maintain sample temperatures of $40^{\circ}C$, and I/O interface to control signals. The tests conducted with different level of flow rate of pump, fan speed, ambient temperature, and intial temperature of mixtures. To evaluate performance of the preprocessor, the supplied volumes, color changes, and temperatures were measured and analyzed. The results showed that the preprocessor could control supplying volumes, mixing, temperatures of samples automatically. The preprocessor showed good performance to be used for portable quality evaluation system of milk.

• Food Quality and Culture
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• 제1권1호
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• pp.22-26
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• 2007

This study was performed to determine the feasibility of developing a healthy yogurt using tofu whey concentrates separated by nanofiltration (NF). The curd yogurt was prepared from whole milk with added skim milk powder, in which the NF powder was substituted at 0, 6.25, 12.5, or 25% for the skim milk powder. The quality characteristics were evaluated for pH, titratable acidity, viscosity, color, and viable cell counts. There were no significant differences in pH or titratable acidity between the control (yogurt with added skim milk powder only) and the yogurts with added NF powder, after 24 hr of fermentation at $37^{\circ}C$. The apparent viscosities of the yogurts with added NF powder were higher ($3,197{\sim}3,574\;cps$) than that of the control yogurt (3,196 cps). Lightness decreased, while yellowness increased, as the amount of NF powder increased. Sensory evaluations showed that the NF powder could be substituted for the skim milk powder at 6.25% without lowering the yogurt quality.

• 한국식품영양과학회지
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• 제29권5호
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• pp.854-859
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• 2000

A functional yogurt was prepared from whole milk (12%) and skim milk (2%) added with green tea and mugwort tea at 3$0^{\circ}C$ for 24 hors. The yogurt product were evaluated for acid production (pH, titratable acidity), number of viable cell, viscosity, sensory property and quality-keeping property. Addition of green tea and mugwort tea remarkably accelerated acid production of yogurt. After 24 hrs incubation, titratabel acidity of green tea and mugwort tea yogurt was 1.46% and 1.62%, respectively and was higher than that (1.30%) of yogurt made with only milk. The propagation of lactic acid bacteria was not stimulated by green tea and mugwort tea and then the number of viable cell in normal (milk) yogurt green tea yogurt and mugwort tea yogurt groups, after 24 hrs incubation, was about 7.2$\times$$10^{8}$, 7.1$\times$$10^{8}$ and 7.0$\times$$10^{8}$/mL, respectively, Viscosity of green tea yogurt was slightly lower than that of milk yogurt (1,840 cps) and viscosity of mugwort tea yogurt was slightly higher than that of mild yogurt. The overall sensory score of green tea yogurt was the best of tested yogurt. When yogurt with green tea and mugwort tea was kept at 5$^{\circ}C$ for 15 days, its quality-keeping property was relatively good.

• Animal Bioscience
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• 제34권5호
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• pp.914-921
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• 2021

Objective: The objective of this study was to compare growth performance, carcass traits and meat quality in young bulls, steers and heifers produced by crossing Limousin bulls with Holstein-Friesian cows, fattened semi-intensively and slaughtered at 18 months of age. Methods: Thirty-one young calves were reared in a conventional production system, and were fed milk replacer, hay and concentrate. At 6 months of age, the animals were divided into groups based on gender, and were fed a total mixed ration composed of grass silage, concentrates I and II in a semi-intensive production system. At the end of the fattening period (18 months), the animals were slaughtered, carcass quality was evaluated, and samples of musculus longissimus thoracis were collected to determine the proximate composition and quality of meat. Results: Bulls were characterized by the highest percentage share of the most valuable cuts in the carcass, and three-rib sections from bull carcasses had the highest lean meat content with low intramuscular fat content (0.93%). No significant differences in carcass conformation, dressing percentage or the percentage share of round in the right half-carcass were found between bulls vs. steers and heifers. Heifers and steers had higher carcass fat content than bulls, which had a positive influence on the sensory properties of beef. In comparison with the meat of bulls, the meat of steers and heifers was characterized by more desirable physical properties and sensory attributes (water-holding capacity, shear force, color lightness, aroma, juiciness, tenderness, flavor). Conclusion: Under the semi-intensive production system, heifers and steers had higher carcass fat content than bulls, which had a positive effect on the sensory properties of beef. Bulls are better suited for intensive systems, which contribute to improving the quality of their meat. The results of this study may encourage producers to breed steers and heifers for beef.

• Food Science and Biotechnology
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• 제17권1호
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• pp.58-65
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• 2008

To see the possibility of irradiation as an alternative to ultra high temperature (UHT) sterilization, the quality characteristics of milk were analyzed. Milk treated by UHT ($135^{\circ}C$ for 4 sec) and irradiation at higher than 3 kGy showed no viable counts after 7 days of storage at $4^{\circ}C$. The contents of certain amino acids of milk, such as Arg, Asp, Glu, Ile, Leu, Lys, Pro, Ser, Thr, and Tyr, were lower in irradiated groups at 10 kGy than in UHT-treated one, but no difference was observed between irradiated milks at less than 5 kGy and UHT. The capillary electrophoresis (CE) patterns of the milk irradiated at 10 kGy showed a similar trend to the raw milk, low temperature long time (LTLT, $63^{\circ}C$ for 30 min), and high temperature short time (HTST, $72^{\circ}C$ for 15 sec) treated. However, the CE pattern of UHT-treated milk was different. Rennet coagulation test agreed with the CE results, showing that all milk samples were coagulated by rennet addition except for UHT-treated milk after 1 hr. These results suggest that irradiation of milk reduce the content of individual amino acids but it may not induce severe conformational change at a protein level when compared with UHT treatment.

• Food Science and Biotechnology
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• 제15권6호
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• pp.844-850
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• 2006

This study was designed to compare various quality characteristics, such as nutrient composition and physicochemical and sensory properties of freeze-concentrated milk made by a newly developed continuous multi-stage process with those of evaporated milk. The freeze concentration process reduced the water content up to 73%. Most of the physicochemical properties of evaporated milk were different from raw milk; however the freeze-concentrated milk showed little difference from the raw milk. The thiobarbituric acid value and free fatty acid concentrations were significantly greater in the evaporated milk than in the freeze-concentrated milk. Several effects on sensory characteristics, such as off-taste, were significantly stronger in the evaporated milk. Overall, this study indicates that the newly developed freeze concentration technique results in improved physicochemical and sensory properties, and has little effect on most nutrient levels when compared with the evaporation process. Further research is necessary to further elucidate the chemical and sensory properties of freeze-concentrated milk.

• Journal of Dairy Science and Biotechnology
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• 제31권2호
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• pp.187-194
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• 2013

노년층에 특화된 기능성 발효유를 개발하기 위하여 버섯 추출물이 첨가된 발효유 3종(상황, 영지, 표고)을 제조하여 품질특성과 항산화 활성을 비교하였다. pH는 발효시간이 경과함에 따라 버섯 추출물 첨가구에서 감소하였고, 적정산도와 유산균수 변화는 증가하였다. 일반성분 중에서 조단백질, 탄수화물 및 당류의 함량이 높았으며, 무기질 함량에서는 칼륨, 칼슘, 나트륨, 니켈, 망간 함량이 버섯 추출물 첨가구에서 증가하였다. 관능검사에서는 대체적으로 버섯 추출물을 첨가한 처리구가 대조구에 비하여 낮은 점수를 얻었지만, 표고 추출물 1% 첨가구의 경우 색, 향, 맛, 조직감, 전체 기호도의 모든 항목에서 가장 높은 기호도를 나타냈다. DPPH와 ABTS 라디칼 소거 활성을 측정하여 항산화 활성을 분석한 결과, 버섯 추출물 첨가구에서 항산화 활성이 매우 증가하였으며, 특히 영지 추출물이 첨가된 발효유의 항산화 효과가 가장 우수하였다. 또한 저장기간에 따른 버섯 발효유의 품질평가 결과, pH, 적정산도, 유산균수는 품질 변화에는 큰 영향을 미치지 않았다. 따라서 영양학적 및 기능적으로 우수한 새로운 기능성 발효유 개발이 가능할 것으로 사료된다.

• Asian-Australasian Journal of Animal Sciences
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• 제26권2호
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• pp.275-281
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• 2013

The objective of this study was to determine the effect of slaughter season on the fatty acid profile in four types of fat deposits in crossbred (Polish Holstein Friesian Black-and-White${\times}$Limousine) beef bulls. The percentage share of fatty acids was determined by gas chromatography and were divided into the following categories of fatty acids: saturated (SFAs), unsaturated (UFAs), monounsaturated (MUFAs), polyunsaturated (PUFAs), desirable hypocholesterolemic (DFAs) and undesirable hypercholesterolemic (OFAs), n-3 and n-6. Perinephric fat was characterized by the highest SFA concentrations (59.89%), and subcutaneous fat had the highest MUFA content (50.63%). Intramuscular fat was marked by a high percentage share of PUFAs and the highest PUFA/SFA ratio. The slaughter season had a significant effect on the levels of C18:3, C20:4 ($p{\leq}0.01$) and conjugated linoleic acid ($p{\leq}0.05$). There was an interaction between the slaughter season and fat type for the content of C20:4 ($p{\leq}0.01$) and C20:5 ($p{\leq}0.05$). The results of this study show that beef from cattle slaughtered in the summer season has a higher nutritional value and more health-promoting properties.