• 한국축산식품학회지
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• 제33권5호
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• pp.565-571
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• 2013

An enzyme ${\beta}$-galactosidase or ${\beta}$-galactohydrolase [EC3.2.1.23], commonly called lactase, mediates galacto-oligosaccharide (GOS) synthesis under conditions of high substrate concentrations. Also, lactase hydrolyzes ${\beta}$($1{\rightarrow}4$) lactose into glucose and galactose, the latter is successively transferred to free lactose to make various oligosaccharides via transgalactosylation. GOS is non-digestible to human digestive enzymes and has been used as a functional prebiotics. Among the 24 lactic acid bacteria (LAB) strains used, Lactobacillus paracasei YSM0308 was selected based on its exhibition of the highest ${\beta}$-galactoside hydrolysis activity, and the crude lactase was prepared for examination of reaction conditions to affect the GOS synthesis. Lactase activity was measured with a spectrophotometer using ONPG (o-nitropheyl ${\beta}$-D-galactopyranoside) method. Lactase activity was not detected in the culture supernatant and was mostly present in the cell pellet after centrifugation. Activity of the crude lactase preparation ranges from102 to 1,053 units/mL, with the highest activity determined for L. paracasei YSM0308. Optimal conditions for GOS synthesis are as follows: concentration of whey powder, pH, temperature, and time were 30%, pH 6.5-7.0, $30^{\circ}C$, and 4 h, respectively. The final GOS concentration was 19.41% (w/v) by the crude YSM0308 lactase, which was obtained from strain YSM0308 grown in the 10% (w/v) reconstituted whey-based medium.

• Journal of Nutrition and Health
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• 제40권8호
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• pp.769-778
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• 2007

Using ICP-AES, we analyzed manganese content in 366 foods consumed frequently by Koreans. For the analysis, it was included a total of 366 foods such as 51 kinds of grains, 7 kinds of potatoes and starches, 7 kinds of sugars and sweeteners, 12 kinds of legumes, 11 kinds of nuts and seeds, 68 kinds of vegetables, 7 kinds of mushrooms, 33 kinds of fruits, 13 kinds of meats, 4 kinds of eggs, 48 kinds of fishes and shellfishes, 7 kinds of seaweeds, 16 kinds of milks, 8 kinds of oils and fats, 27 kinds of beverages, 34 kinds of seasonings, 13 kinds of processed foods and others. Among the grains, starches and sugars, manganese content of rice was 0.745 mg/100g. As for legumes, the content of manganese in soybean milk was 0.033 mg/100g and in black beans was 4.075 mg/100g. In nuts and seeds, the content of manganese in gingko nuts was 0.268 mg/100g while that in pine nuts was 8.872 mg/100g. Among the vegetables, manganese contents were 0.061 mg/100g in cherry tomato and 14.017 mg/100g in ginger. In mushrooms, the highest manganese content was displayed in ear mushroom at 10.382 mg/100g. Dried jujube and shrimp were found to be the fruits and fishes with high manganese contents at 2.985 mg/100g and 3.512 mg/100g, respectively. Among dairy foods, oils and beverages, manganese content was the highest in instant coffee powder at 2.577 mg/100g. Seasonings and processed foods posted 0.010 mg/100g in Sagolgomtang, instant soup and 23.846 mg/100g in pepper. In a furture, more various food for manganese content needs to be analyzed and a reliable food database should be compiled from the findings of researches in order to estimate manganese consumption accurately.

• Journal of Animal Science and Technology
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• 제63권3호
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• pp.575-592
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• 2021

In livestock nutrition, natural feed additives are gaining increased attention as alternatives to antibiotic growth promoters to improve animal performance. This study investigated the effects of dietary turmeric supplementation on the growth performance and gut health of weaned piglets. A total of 48 weaned piglets (Duroc × [Landrace × Yorkshire]) were used in a 6-week feeding trial. All piglets were allotted to two dietary treatments: corn-soybean meal basal diet without turmeric (control) and with 1% weight per weight (w/w) turmeric powder (turmeric). The results showed that dietary inclusion of turmeric with the basal diet improved final body weight and total average daily gain (p < 0.05). The concentrations of short-chain fatty acids in the fecal samples, including acetic, butyric, and propionic acids, were higher in the turmeric group (p < 0.05). The villus height-to-crypt depth ratio was higher in the ileum of turmeric-fed piglets (p = 0.04). The 16S rRNA gene sequencing of fecal microbiota indicated that, at the phylum level, Firmicutes and Bacteroidetes were the most predominant taxa in all fecal samples. Bacteroidetes were significantly decreased in the turmeric group compared to the control group (p = 0.021). At the genus level, turmeric showed a decreased abundance of Prevotella (p = 0.021) and an increasing trend of Lactobacillus (p = 0.083). Among the total detected species, nine bacterial species showed significant differences between the two groups. The results of this study indicated that turmeric altered the gut microbiota and shortchain fatty acid production. This suggests that turmeric could be used as a potential alternative growth promoter for piglets.

• 한국축산식품학회지
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• 제41권2호
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• pp.173-184
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• 2021

Clean labeling is emerging as an important issue in the food industry, particularly for meat products that contain many food additives. Among synthetic additives, nitrite is the most important additive in the meat processing industry and is related to the development of cured color and flavor, inhibition of oxidation, and control of microbial growth in processed meat products. As an alternative to synthetic nitrite, preconverted nitrite from natural microorganisms has been investigated, and the applications of pre-converted nitrite have been reported. Natural nitrate sources mainly include fruits and vegetables with high nitrate content. Celery juice or powder form have been used widely in various studies. Many types of commercial starter cultures have been developed. S. carnosus is used as a critical nitrate reducing microorganism and lactic acid bacteria or other Staphylococcus species also were used. Pre-converted nitrite has also been compared with synthetic nitrite and studies have been aimed at improving utilization by exploiting the strengths (positive consumer attitude and decreased residual nitrite content) and limiting the weaknesses (remained carcinogenic risk) of pre-converted nitrite. Moreover, as concerns regarding the use of synthetic nitrites increased, research was conducted to meet consumer demands for the use of natural nitrite from raw materials. In this report, we review and discuss various studies in which synthetic nitrite was replaced with natural materials and evaluate pre-converted nitrite technology as a natural curing approach from a clean label perspective in the manufacturing of processed meat products.

• 한국축산식품학회지
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• 제41권5호
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• pp.894-904
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• 2021

Microencapsulation is a protective process for materials that are sensitive to harsh conditions encounted during food manufacture and storage. The objectives of this research were to manufacture a milk protein-based delivery system (MPDS) containing Lactobacillus rhamnosus GG (LGG) using skim milk powder and to investigate the effects of manufacturing variables, such as reaction temerpature and holding time, on the physiccohemical properties of MPDS and viability of LGG under dairy food processing and storage conditions. MPDS was prepared using chymosin at varing reaction temperatures from 25℃ to 40℃ for 10 min and holding times from 5 to 30 min at 25℃. The morphological and physicochemical properties of MPDS were evaluated using a confocal laser scanning microscope and a particle size analyzer, respectively. The number of viable cells were determined using the standard plate method. Spherical-shaped MPDS particles were successfully manufactured. The particle size of MPDS was increased with a decrease in reaction temperature and an increase in holding time. As reaction temperature and holding time were increased, the encapsulation efficiency of LGG in MPDS was increased. During pasteurization, the use of MPDS resulted in an increase in the LGG viability. The encapsulation of LGG in MPDS led to an increase in the viability of LGG in simulated gastric fluid. In addition, the LGG viability was enhanced with an increase in reaction temperature and holding time. In conclusions, the encapsulation of LGG in MPDS could be an effective way of improving the viability of LGG during pasturization process in various foods.

• Animal Bioscience
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• 제37권6호
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• pp.1031-1040
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• 2024

Objective: This study aimed to evaluate the effect of feeding milk replacer (MR) with varying levels of lactose and the increased supply of total solids (from 750 to 960 g/d) on performance, blood metabolites, and health of Holstein male calves during the preweaning period. Methods: Forty newborn Holstein calves (10 per treatment) were blocked according to birth weight and date of birth and distributed in a randomized block design to different liquid diets: Whole milk powder (WMP) diluted to 125 g/L solids; MR with 48% lactose (48L), diluted to 125 g/L solids; MR with 53% lactose (53L), diluted to 125 g/L solids; 53L MR corrected to 160 g/L solids (16TS) by the inclusion of a solid corrector. Calves were individually housed in wood hutches, fed 6 L/d of the liquid diet, and had free water and starter concentrate access. The study lasted 56 days. Results: Liquid diet intake was higher for calves fed 16TS than for other treatments. Calves fed 16TS presented higher protein and fat intake, followed by those fed WMP and the 48L or 53L MRs. Lactose intake was higher for 16TS-fed calves, followed by 53L, 48L, and WMP-fed calves. Starter and total dry matter intake did not differ among liquid diets. The average daily gain was higher for 16TS than 48L-fed calves, with the other treatments being intermediary. The lowest feed efficiency was observed for calves fed 48L. No effects on health were observed, as well as on selected blood metabolites, except for albumin concentration, which was higher for calves fed 16TS and WMP. Conclusion: Higher total solids content (160 g/L) in MR increases nutrient intake and consequently improves the performance of dairy calves. Feeding MRs with levels of lactose up to 53% of the DM had no deleterious effect on the performance or health of the calves.

• Journal of Animal Science and Technology
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• 제66권5호
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• pp.981-998
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• 2024

This study was to investigate effects of different phytogenic feed additives (PFA) in grower finishing pigs with stressed by high stocking density. A total of 84 growing pigs ([Landrace × Yorkshire] × Duroc) with initial body weight (BW) of 28.23 ± 0.21 kg were used for 10 weeks (4 replicate pens with 3 pigs per pen). The dietary treatment consisted of basal diets in animal welfare density (positive control [PC]), basal diet in high stocking density (negative control [NC]), NC + 0.04% bitter citrus extract (PT1), NC + 0.01% microencapsulated blend of thymol & carvacrol (PT2), NC + 0.10% mixture of 40% bitter citrus extract and 10% microencapsulated blend of thymol and carvacrol (PT3), NC + 0.04% premixture of grape seed and grape marc extract, green tea and hops (PT4), and NC + 0.10% fenugreek seed powder (PT5). The reduction of space allowance significantly decreased (p < 0.05) growth performance (average daily gain, average daily feed intake, feed efficiency) and nutrient digestibility (dry matter, crude protein). Also, the fecal score of NC group increased (p < 0.05) compared with other groups. In blood profiles, lymphocyte decreased (p < 0.05), and neutrophil, cortisol, TNF- α increased (p < 0.05) when pigs were in high stocking density. Basic behaviors (feed intake, standing, lying) were inactive (p < 0.05) and singularity behavior (biting) were increased (p < 0.05) under high stocking density. However, PFA groups alleviated the negative effects such as reducing growth performance, nutrient digestibility, increasing stress indicators in blood and animal behavior. In conclusion, PFA groups improved the health of pigs with stressed by high stocking density and PT3 is the most effective.

• 한국축산식품학회지
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• 제26권4호
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• pp.525-531
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• 2006

본 실험에서는 생리 활성 효과가 기대되며 영양학적 가치가 높은 클로렐라를 실용적인 식재료로 활용하는 방안의 하나로 클로렐라 Appenzeller 치즈를 제조하여 클로렐라 분말이 치즈숙성 중 유산균의 생육과 치즈 pH의 변화 및 단백질의 분해도에 미치는 영향을 살펴보고, 제품의 관능적 특성을 측정하여 제품의 품질을 평가하였다. 대조구보다 클로렐라가 첨가된 치즈에서 유산균수가 다소 높게 유지되었고, pH는 클로렐라 첨가구에서 대체로 더 낮았다. NPN과 NCN은 2.0% 첨가구가 대조구나 다른 첨가구보다 상대적으로 높았다. 조지방과 조회분의 함량은 대조구가 첨가구보다 다소 높았고, 수분은 1.0%에서, 조단백 함량은 2.0%에서 가장 높았다. 클로렐라 분말을 첨가한 치즈들은 관능 평가에서 대조구보다 낮은 점수를 보였으나 1% 이하의 첨가 수준에서는 맛의 변화를 느낄 수 없었으며 특히 2.0% 첨가구에서 가장 낮은 점수가 얻어졌다 Appenzeller 치즈에 대한 클로렐라 분말의 적정 첨가 수준은 치즈의 맛, 외관, 향미 및 조직감 등을 고려했을 때 0.5%수준이 적합한 것으로 사료되었다.

• Journal of Dairy Science and Biotechnology
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• 제34권2호
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• pp.99-116
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• 2016

본 시험은 sialic acid가 7%를 함유하도록 제조한 유청가수분해단백분말제제(whey protein of hydrolysis)의 기능성 식품원료로 개발을 위한 동물안전성을 평가함에 연구목표를 두었다. GMP를 원료로 제조한 시험물질은 sialic acid 7%(v/v)와 원료인 GMP 가수분해 단백질이 93%로 구성되어 있었다(시험명: 7%-GNANA). 시험물질의 독성 유무는 한국식품의약안전청(KFDA, 2014)과 OECD(2008)의 의약품 등의 독성시험 기준에 따라 실시하였다. 평가방법으로서, 시험물질의 투여용량을 0, 1,250, 2,500 및 5,000 mg/kg/day로 하여 SPF Sprague-Dawley 계열 암수 랫드에 90일 동안 반복경구투여하였을 때 나타나는 독성 여부를 평가하였다. 평가항목으로서는 사망률, 일반증상관찰, 체중 변화, 사료 섭취량 측정, 안검사, 요검사, 혈액학적 및 혈액생화학적 검사, 부검 시 장기의 중량측정, 부검 시 육안적 검사 및 조직병리학적 검사 등을 평가하였다. 90일 반복경구투여 실험결과로서, 시험물질투여 및 관찰기간 동안 사망동물은 발생하지 않았다. 또한 일반증상, 체중 변화, 사료섭취량, 안과학적 검사, 요검사 그리고 혈액학적 및 혈액이화학적 이상 및 혈액응고검사에서 대조군 대비 특이한 변화는 관찰되지 않았다(p<0.05). 부검 및 병리조직학적 평가 결과, 암수 모두에서 시험물질-유래 중요한 변화 없이 시험물질-유래 경미한 변화(non-adverse effect)만인 5,000 mg/kg/day에서 확인되었다. Weight-based classification(독성 강도에 따른 분류)을 적용한 최종 독성평가 결과, 수컷의 경우 NOEL(No Observed Effect Level)은 5,000 mg/kg/day 그리고 암컷의 경우는 NOAEL(No Observed Adverse Effect Level)은 5,000 mg/kg/day로 최종 확인되었다. 따라서, 암수 모두에서 시험물질의 NOAEL은 투여최대용량인 5,000 mg/kg/day로 확인되었다. 결론적으로, GMP를 원료로 하여 제조한 7%-GNANA(유청가수분해단백분말)는 투여가능 최대용량에서도 독성이 없는 안전한 천연물이라는 것을 확인하였고, 의약품이나 기능성 식품으로서의 개발 가능성을 확인하였다.

• Journal of Dairy Science and Biotechnology
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• 제30권2호
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• pp.93-109
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• 2012

This study was performed to investigate the effects of added whey protein concentrates (WPC) and whey powder (WP) on the quality and shelf life of Tofu, a traditional food in Korea. Combined whey powder and whey protein concentrates were obtained at drainage after the casein was separated by using rennet enzyme or acidification of milk. We manufactured whey Tofu and evaluated its nutritional quality by testing, the general composition for yield, moisture, pH, crude protein, crude fat, carbohydrate, rheology, sensory properties, and change during storage. 1. The general compositions of WPC and WP were as follows: (a) WPC: moisture, 5.9%; crude protein, 56.2%; crude fat, 0.1%; carbohydrate, 32.6%; ash, 5.2%; and pH 5.93 and (b) WP: moisture, 3.7%; crude protein, 13.2%; crude fat, 1.6%; carbohydrate, 74.4%; ash, 7.1%; and pH, 6.65. 2. The yield of Tofu was as follows: (a) in WPC, the content was $CaCl_2$:GDL=6:4 > $CaCl_2$:GDL=9:1 > $CaCl_2$:GDL=7:3 > $CaCl_2$:GDL=8:2 and (b) in WP, 2% addition was the highest (265%) at $13.3g/cm^2$, but with 4% addition WP was the lowest (184%) at $22.2g/cm^2$. 3. The moisture content of Tofu was as follows: (a) in WPC, the content was $CaCl_2$:GDL = 6:4 > $CaCl_2$:GDL=9:1 > $CaCl_2$:GDL=7:3 > $CaCl_2$:GDL=8:2 and (b) in WP, 2% addition was the highest at 79.82% ($13.3g/cm^2$), but 4% was the lowest at 75.18% ($22.2g/cm^2$). 4. The pH of Tofu was as follows: (a) in WPC, the value was WPC 6% > WPC 4% > WPC 2% > control and $CaCl_2$:GDL=6:4 > $CaCl_2$:GDL=8:2 > $CaCl_2$:GDL=9:1 > $CaCl_2$:GDL=7:3 and (b) in WP, WP 4% > WP 2% > control. 5. The ash content of Tofu was as follows: (a) in WPC, the content was $CaCl_2$:GDL=8:2 > $CaCl_2$:GDL=7:3 > $CaCl_2$:GDL=6:4 > $CaCl_2$:GDL=9:1 and (b) in WP, there was no difference between 2% and 4% addition. 6. The crude protein content of Tofu was as follows: (a) in WPC, the content was $CaCl_2$:GDL=8:2 > $CaCl_2$:GDL=7:3 > $CaCl_2$:GDL=9:1 > $CaCl_2$:GDL=6:4 and (b) in WP, there was no difference between 2% and 4% addition. 7. The crude fat content of Tofu was as follows: (a) in WPC, the content was $CaCl_2$:GDL=8:2 > $CaCl_2$:GDL=7:3 > $CaCl_2$:GDL=9:1 > $CaCl_2$:GDL=6:4 and (b) in WP, values decreased with increasing pressed weight. 8. The carbohydrate content of Tofu was as follows: (a) in WPC, the content was $CaCl_2$:GDL=8:2 > $CaCl_2$:GDL=7:3 > $CaCl_2$:GDL=6:4 > $CaCl_2$:GDL=9:1 and (b) in WP, values increased with increasing pressed weight. 9. The rheology test results of Tofu were as follows: (a) in WPC, hardness and brittleness was highest with $CaCl_2$:GDL=8:2 and 6% added WPC. Cohesiveness was highest with $CaCl_2$:GDL=6:4 and 2% added WPC. Elasticity was the highest with $CaCl_2$:GDL=7:3 and the added WPC control. (b) in WP, hardness was the highest with $22.2g/cm^2$ and added WP control. Cohesiveness was the highest with $17.8g/cm^2$ and added WP 2%. Elasticity was the highest with $17.8g/cm^2$ and added WP 4%. Brittleness was the highest with $17.8g/cm^2$ and added WP control. 10. The sensory test results of Tofu were as follows: (a) in WPC, the texture, flavor, color, and smell were the highest with $CaCl_2$:GDL=6:4 and 6% added WPC. (b) in WP, the texture was the highest in the control with $22.2g/cm^2$. Flavor and smell were the highest in WP 2% and $22.2g/cm^2$. Color was the highest in WP 2% and $17.8g/cm^2$. 11. The quality change of Tofu during storage was as follows: (a) in WPC, after 60 h, all samples began to get spoiled and their color changed, and mold began to germinate. (b) in WP, the result was similar, but the rate of spoilage was more rapid than that in the control.