• Korean journal of food and cookery science
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• v.11 no.3
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• pp.316-322
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• 1995

A curd yogurt was prepared from milk added with skim milk powder or four kinds of cereal. Addition of cereals markedly stimulated acid production by Leuc. mesenteroides. The acidity significantly increased during fermentation by Leuc. mesenteroides for 30 hours while pH significantly decreased during fermentation. The number of viable cells markedly increased until the first 12 or 18 hours of fermentation by Leuc. mesenteroides. Acetaldehyde, acetone, ethanol, diacetyl, butanol and acetoin in curd yogurt were detected by gas chromatographic analysis. Among these compounds, acetaldehyde, ethanol, diacetyl and acetoin were produced during fermentation by Leuc. mesenteroides.

• Journal of Microbiology and Biotechnology
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• v.30 no.9
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• pp.1321-1334
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• 2020

Beef, pork, chicken and milk are considered representative protein sources in the human diet. Since the digestion of protein is important, the role of intestinal microflora is also important. Despite this, the pure effects of meat and milk intake on the microbiome are yet to be fully elucidated. To evaluate the effect of beef, pork, chicken and milk on intestinal microflora, we observed changes in the microbiome in response to different types of dietary animal proteins in vitro. Feces were collected from five 6-week-old pigs. The suspensions were pooled and inoculated into four different media containing beef, pork, chicken, or skim milk powder in distilled water. Changes in microbial communities were analyzed using 16S rRNA sequencing. The feces alone had the highest microbial alpha diversity. Among the treatment groups, beef showed the highest microbial diversity, followed by pork, chicken, and milk. The three dominant phyla were Proteobacteria, Firmicutes, and Bacteroidetes in all the groups. The most abundant genera in beef, pork, and chicken were Rummeliibacillus, Clostridium, and Phascolarctobacterium, whereas milk was enriched with Streptococcus, Lactobacillus, and Enterococcus. Aerobic bacteria decreased while anaerobic and facultative anaerobic bacteria increased in protein-rich nutrients. Functional gene groups were found to be over-represented in protein-rich nutrients. Our results provide baseline information for understanding the roles of dietary animal proteins in reshaping the gut microbiome. Furthermore, growth-promotion by specific species/genus may be used as a cultivation tool for uncultured gut microorganisms.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.12
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• pp.1790-1797
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• 2002

Lactic acid bacteria were isolated from piglets and chicken and characterized. Lactic acid bacteria showing resistance to low pH and bile, adhesion to intestinal epithelium cells, and the inhibition of Escherichia coli and Salmonella spp. were identified as Lactobacillus acidophilus. L. acidophilus PF01 survived for 2 h in MRS broth adjusted to pH 2. L. acidophilus CF07 was less resistant than L. acidophilus PF01 to pH 2, but survived at pH 2.5 for 2 h. Both of isolates were able to grow in MRS broth containing 0.3% (w/v) bile, with L. acidophilus CF07 being more tolerant to bile than L. acidophilus PF01. L. acidophilus PF01 and CF07 adhered specifically to the duodenal and jejunal epithelium cells of piglet, and the cecal and duodenal epithelium cells of chicken, respectively. Both of isolates did not adhere to the epithelium cells of the various animal intestines from which they were isolated. When L. acidophilus was cultured with E. coli and Salmonella spp. in MRS broth, MRS broth containing 2% skim milk powder or modified tryptic soy broth at $37^{\circ}C$, L. acidophilus PF01 and CF07 inhibited the growths of E. coli K88 and K99, and S. enteritidis and S. typhimurium, respectively. Both of isolates were found to possess the essential characteristics of probiotic lactic acid bacteria for piglet and chicken.

• Food Science of Animal Resources
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• v.30 no.1
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• pp.36-41
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• 2010

The Hen's egg is widely used in many processed foods as an ingredient and is one of the most prevalent food allergens in children. To detect egg proteins in processed foods, we developed a competitive indirect enzyme-linked immunosorbent assay (ciELISA) using an anti-ovomucoid (OM) antibody, which was produced by immunization of rabbits with OM, the most heat-stable component of the egg proteins. The detection limit of this quantitative assay system was 30 ng/mL. Cross-reactivity of the anti-OM antibody toward OM, ovalbumin, skim milk, casein, whey protein isolate, and isolated soy protein was 100, 0.4, 0.2, 0.04, 0, and 0%, respectively. In the spike test of egg white powder in milk replacer, commercial sausage, and in-house sausage, the assay recoveries ($mean{\pm}SD$) were $129{\pm}13.7%$, $73.9{\pm}12.5%$, and $65.5{\pm}13.6%$, respectively. When egg white in a commercial crab meat analog and sausage was determined by ciELISA, the assay recovery was found to be 108% and 127%, respectively. The combined results of this study indicate that this novel ciELISA for OM detection could be applied for the quantification of hen's egg proteins in processed foods.

• Korean Journal of Agricultural Science
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• v.38 no.3
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• pp.485-491
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• 2011

Yogurt was prepared from skim milk added with 2, 4 or 6% of green whole grain of barley, wheat, glutinous rice and common rice, respectively. Changes in pH, titratable acidity, viable cell counts and viscosity during fermentation were monitored and its sensory evaluation was also performed. The optimum level of additives such as green whole grain of barley, wheat, glutinous rice and common rice for yogurt manufacture was selected to 2%. The samples added with green whole grain of barley and wheat powders reached pH 4.5 in 12 hours. After 4 hours of fermentation, pH, the viable cell counts and viscosity in samples added with 2% green whole grain of barley, wheat, glutinous rice and common rice powders were the highest. Especially, in overall sensory evaluation using 5 parameters, the sensory scores of glutinous rice and common rice 2% yogurts were significantly high. From this experiment, the additives optimum level of glutinous rice and common rice powders was selected to be 2%.

• Food Science of Animal Resources
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• v.28 no.3
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• pp.306-311
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• 2008

The aim of this work was to examine the reduction in antigenicity of milk proteins in powdered milk by gamma irradiation which is increasingly used for food safety. Skim milk powder samples were exposed to irradiation doses of 1, 5, and 10 kGy. A greater reduction of ${\alpha}_{S1}$-casein and ${\beta}_{A1}$-casein was found than ${\alpha}_{S0}$-casein and ${\beta}_{A2}$-casein by capillary electrophoresis. Competitive indirect ELISA and passive cutaneous anaphylaxis tests using guinea pigs showed a reduction in antigenicity of powdered milk by 10kGy gamma irradiation. These results indicated that gamma irradiation reduce allergenicity of milk proteins by structural changes of ${\alpha}_{S1}$-casein and ${\beta}_{A1}$-casein, and can be useful for dairy products.

• Korean Journal of Food Science and Technology
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• v.25 no.2
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• pp.130-135
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• 1993

A curd yogurt was prepared from milk added with skim milk powder of four kinds of cereal. The effect of cereals at 2%(w/v) level on acid production by lactic acid bacteria in milk was investigated. The effect of cereals on quality of curd yogurt (apparent viscosity, sensory property) was also examined. Addition of cereals markedly stimulated acid production by lactic acid bacteria. Among three organisms tested, L. acidophilus produced more acid than others. Apparent viscosity of curd yogurt added with corn was the highest while that with barley was the lowest. Curd yogurt fermented with L. acidophilus showed characteristics of thioxotropic flow. Apparent viscosity of curd yogurt added with cereal markedly increased between 6 and 24 hours of fermentation. Sensory property of curd yogurt added with wheat was judged as better than reference sample, but that with barley was lodged as the worst among all samples.

• Korean Journal of Food Science and Technology
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• v.24 no.5
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• pp.470-476
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• 1992

The curd yogurt was prepared from milk added with skim milk powder or three Tongil rices of different storage period. The effect of storage period of rice on acid production by lactic acid bacteria in milk containing rice of 2%(w/v) was investigated. The effect of storage period of rice on quality of curd yogurt(sensory property, viscosity and keeping quality) was also examined. Addition of rice stimulated acid production by lactic acid bacteria more than control(milk yogurt). Storage period of rice did not significantly affect acid production by lactic acid bacteria though stimulating effect of rice on acid production was slightly different among species. Sensory property of curd yogurt added with rice was not significantly affected by storage period of rice. Apparent viscosity of curd yogurt added with rice increased in proportion to storage period of rice. Curd yogurt showed characteristics of thixotropic flow. When curd yogurt added with rice was kept at $5^{\circ}C$ for 15 days, its keeping quality was relatively good and was not markedly affected by storage period of rice.

• Journal of Animal Science and Technology
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• v.46 no.4
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• pp.677-686
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• 2004

The objective of this experiment was to select the best strain of lactic acid bacteria for the manufacture of new type of yogurt with rice powders. Changes in pH, titratable acidity, viable cell counts, viscosity, organic acid contents, carbohydrates during fennentation were monitored and sensory evaluation were examined. The yogurt added with 4% rice or skim milk powders and L. salivarius ssp. salivarius culture did not reach pH 4.5, because the production of acids in this media for the culture was weak. The yogurt added with 4% rice or skim milk powder with L. casei, the pH was low and the titratable acidity was high, and therefore the quality of yogurt after 8 hours from fermentation was not high. The yogurt added with 4% rice or skim milk powders with a mixed culture of B. longum, L. acidophilus, Streptococcus salivarius ssp. thermophilus was considered best for achieving pH 4.5 and titratable acidity of 1.0 % from 8 to 14 hours. The yogurt with a mixed culture had more acetic acid. Galactose was accumulated when L. salivarius ssp. salivarius or the mixed culture were used for fermenting yogurt. In sensory evaluation, the yogurt with the mixed culture received high overall sensory score. From these results, a mixed culture of B. longum, L. acidophilus, Streptococcus salivarius ssp. thermophilus was identified as the best for the manufacture of yogurt added with rice powder.

• Korean Journal of Food Science and Technology
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• v.25 no.2
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• pp.136-141
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• 1993

A curd yogurt was prepared from milk added with skim milk powder or four kinds of cereal. The effect of cereals at 2%(w/v) level on the pattern of volatile aroma compounds in curd yogurt was investigated. Acetaldehyde, acetone, ethanol, diacetyl, butanol and acetoin in curd yogurt were detected by gas chromatographic analysis. Among these compounds, acetaldehyde, ethanol, diacetyl and acetoin were produced during fermentation by Lactobacillus acidophilus (KCTC 2182). The addition of cereals did not affect markedly general pattern of volatile aroma compounds in curd yogurt. The amount of acetoin and ethanol markedly increased until the first 6 hours of fermentation, and then increased mildly until 24 hours. The amount of diacetyl markedly increased until the first 6 hours and then decreased slightly. Acetaldehyde was first detected by gas chromatograph after 18 hours of fermentation.