• Journal of the FoodService Safety
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• v.3 no.1
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• pp.8-18
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• 2022

Dry-aging is one of the traditional aging processes, especially for beef. This aging process is being popular, because it produces unique brown/roasted flavor and texture that consumers prefer. However, as it is exposed to outside without packaging food safety concerns have been raised. The objective of this study was to investigate the presence of total aerobic bacteria (TAB) and pathogenic bacteria in manufacturing environment and suggest the safety management plan for the production of dry-aged meat. Surface samples from 66 environmental and 6 beef carcass samples were collected. According to the monitoring results, the contamination levels of TAB were in the order of shelves (5.4±1.1 Log CFU/cm²), cotton gloves (2.9±0.2 Log CFU/cm²), and door knobs (2.8±0.4 Log CFU/cm²) in the dry-aging room. In the door knobs, the level of mold was higher than that of yeast. These results indicate that the mold spores may be cross-contaminated with environmental factors inside the aging room. The risk factors that may occur during the manufacturing process were presented and possibility of risk was determined. From the aspect of microbiology, aging and trimming steps were determined as the critical control points. The temperature of the aging room should be maintained below 10℃ and the humidity below 75-85%. Based on the monitoring and the risk assessment of the dry-aging process, we prepared the safety management plan for the production of dry-aged meat, and it should be useful in improving the food safety of dry-aged meat.

• Korean Journal of Food Science and Technology
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• v.42 no.6
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• pp.739-742
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• 2010

In order to select a superior yeast, 8 kinds of commercial active dry yeasts (Lalvin 1116, Lalvin 1118, Lalvin D-47, Lalvin Bourgovin, Parisienne, Fermivin, Red Star Monrachet, and Red Star Premier Cuvee) were utilized for omija wine fermentation. During fermentation, the physicochemical characteristics and sensory properties of the various omija wines were evaluated. According to the results, pH and titratable acidity were in ranges of 3.0-3.3% and 1.8-2.4%, respectively. Sugar content was $24^{\circ}Bx$ at early fermentation and changed to $8.4-10.2^{\circ}Bx$ at 24 days of fermentation. While the omija wines fermented by Lalvin D-47 and Red Star Premier Cuvee showed the highest alcohol contents (13.0%), the omija wine fermented by Parisienne showed the lowest alcohol content (10.8%). The omija wine fermented by Lalvin 1118 had an alcohol content of 12.0% and showed the lowest yeast count of 5.8 log CFU/mL. Hunter's values (L, a, and b) were all different among the 8 omija wines. Moreover, the omija wine fermented by Lalvin 1118 showed the highest scores for taste ($6.75{\pm}1.68$), swallowing ($6.65{\pm}1.50$), and overall acceptability ($6.70{\pm}1.34$). It is concluded that Lalvin 1118 was the best yeast among 8 tested commercial active dry yeasts, having a high potential for omija wine fermentation.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.2
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• pp.211-218
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• 2016

This study evaluated the effect of Candida norvegensis (C. norvegensis) viable yeast culture on in vitro ruminal fermentation of oat straw. Ruminal fluid was mixed with buffer solution (1:2) and anaerobically incubated with or without yeast at $39^{\circ}C$ for 0, 4, 8, 16, and 24 h. A fully randomized design was used. There was a decrease in lactic acid (quadratic, p = 0.01), pH, (quadratic, p = 0.02), and yeasts counts (linear, p<0.01) across fermentation times. However, in vitro dry matter disappearance (IVDMD) and ammonia-N increased across fermentation times (quadratic; p<0.01 and p<0.02, respectively). Addition of yeast cells caused a decrease in pH values compared over all fermentation times (p<0.01), and lactic acid decreased at 12 h (p = 0.05). Meanwhile, yeast counts increased (p = 0.01) at 12 h. C. norvegensis increased ammonia-N at 4, 8, 12, and 24 h (p<0.01), and IVDMD of oat straw increased at 8, 12, and 24 h (p<0.01) of fermentation. Yeast cells increased acetate (p<0.01), propionate (p<0.03), and butyrate (p<0.03) at 8 h, while valeriate and isovaleriate increased at 8, 12, and 24 h (p<0.01). The yeast did not affect cellulolytic bacteria (p = 0.05), but cellulolytic fungi increased at 4 and 8 h (p<0.01), whereas production of methane decreased (p<0.01) at 8 h. It is concluded that addition of C. norvegensis to in vitro oat straw fermentation increased ruminal fermentation parameters as well as microbial growth with reduction of methane production. Additionally, yeast inoculum also improved IVDMD.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.2
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• pp.230-240
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• 2016

Information on the effects of different yeast species on ruminal fermentation is limited. This experiment was conducted in a $3{\times}4$ factorial arrangement to explore and compare the effects of addition of three different live yeast species (Candida utilis 1314, Saccharomyces cerevisiae 1355, and Candida tropicalis 1254) at four doses (0, $0.25{\times}10^7$, $0.50{\times}10^7$, and $0.75{\times}10^7$ colony-forming unit [cfu]) on in vitro gas production kinetics, fiber degradation, methane production and ruminal fermentation characteristics of maize stover, and rice straw by mixed rumen microorganisms in dairy cows. The maximum gas production (Vf), dry matter disappearance (IVDMD), neutral detergent fiber disappearance (IVNDFD), and methane production in C. utilis group were less (p<0.01) than other two live yeast supplemented groups. The inclusion of S. cerevisiae reduced (p<0.01) the concentrations of ammonia nitrogen ($NH_3$-N), isobutyrate, and isovalerate compared to the other two yeast groups. C. tropicalis addition generally enhanced (p<0.05) IVDMD and IVNDFD. The $NH_3$-N concentration and $CH_4$ production were increased (p<0.05) by the addition of S. cerevisiae and C. tropicalis compared with the control. Supplementation of three yeast species decreased (p<0.05) or numerically decreased the ratio of acetate to propionate. The current results indicate that C. tropicalis is more preferred as yeast culture supplements, and its optimal dose should be $0.25{\times}10^7$ cfu/500 mg substrates in vitro.

• Journal of Aquaculture
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• v.9 no.4
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• pp.329-337
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• 1996

Dietary values of phytoplanktons, concentrated Chlorella and commercial yeasts were investigated for the resting egg production of the Korean rotifer, B. plioatilis S-type. The hatching rate of the resting egg of the rotifer fed on different diets was also studied. The highest production of the resting egg was 3,760 eggs/20 ml with N. oculata. However, the hatching rate was not significant among 4 phytoplankton species. The highest production of resting eggs among 9 diet groups ($\omega$-yeast, baker's yeast, 2 refrigerated Marine Chlorella, frozen Marine Chlorella, frozen Chlorella ($70\%$) + baker's yeast ($30\%$), frozen Chlorella ($30\%$) + baker's yeast ($70\%$), 2 refrigerated freshwater Chiorella) was 283 eggs/ml in the frozen Chlorella ($30\%$) +baker's yeast ($70\%$) and the refrigerated freshwater Chlorella. The highest number of resting egg from 10,000 rotifers and 1 mg dry wieght diet was 5,566 eggs and 2,131 eggs in the frozen Chlorella ($30\%$) + baker's yeast ($70\%$). However, the highest hatching rate of the resting eggs was $67.4\%$ in $\omega$-yeast. In this study, the results suggest that the baker's yeast with a small amount of frozen Chlorella seems to be good feeding regime for the economical production of resting eggs.

• The Korean Journal of Food And Nutrition
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• v.19 no.4
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• pp.392-397
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• 2006

To compare the contents of amino acids in raspberry wine, 5 types of active dry yeast strains (Saccharomyces cerevisiae Montrachet (UCD #522), Saccharomyces bayanus Pasteur Champagne (UCD #595), Saccharomyces cerevisiae Epemay II (CEG), Saccharomyces bayanus Prise do Mousse (PM), Saccharomyces uvarum Latvia W15) were used. In the fermentation experiment two kinds of raspberry wine were used; Rubus coreanus Miquel(RCM), harvested in Gochang, and Rubus crataegifolius Bunge(RCB), harvested in Okcheon. In 5 kinds of RCM raspberry wines, total contents of 17 amino acids were found from $16.77mg/{\ell}$ in the fermented Prise de Mousse, the most amount, to $12.29mg/{\ell}$ in Lalvin W15, the lowest. The content of amino acid in the RCB raspberry wine fermented by Montrachet was approximately 5.5 times higher than that of the RCM raspberry wine; $90.55mg/{\ell}\;to\;16.54mg/{\ell}$. Cystine and isoleucine were detected $2.97mg/{\ell},\;0.34mg/{\ell}$, respectively, in the RCB raspberry wine but not detected in the RCM raspberry wine. The amount of alanine, aspartic acid, and serine in RCB raspberry wine were found approximately 14 to 20 times larger than that of RCM raspberry wine.

• Journal of Food Hygiene and Safety
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• v.19 no.4
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• pp.209-216
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• 2004

Dry rehydratable film methods were compared to conventional methods for the enumeration of microorganisms in Korean traditional foods. Kimchi, doenjang, kochujang, kanjang, takju, sujeongkwa and sikhe were used as Korean traditional foods. $Petrifilm^{TM}$ aerobic count plate, $Petrifilm^{TM}$ coliform count plate, $Petrifilm^{TM}$ E. coli/coliform count plate, $Petrifilm^{TM}$ yeast and mold count plate and $Petrifilm^{TM}$ staph express count plate were compared to plate count agar, most probable number (MPN) for coliform, MPN for E. coli, potato dextrose agar and coagulase test, respectively. Regression analysis indicated that correlation coefficient values were 0.974-0.998, 0.913-0.995, 0.955-0.978, 0.968-0.986 and 0.998-0.999 for total aerobic bacteria, yeast and mold, coliform, E. coli and S. aureus, respectively. There were no significant differences between two methods, suggesting that $Petrifilm^{TM}$ plates can be used as an alternative to conventional method for the determination of microorganisms in Korean traditional foods.

• Journal of the Korea Organic Resources Recycling Association
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• v.24 no.3
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• pp.91-99
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• 2016

The objective of this study was to investigate characteristics of inorganic components contained in liquid fertilizer produced using fish meal under different condition. Addition of dry yeast to liquid fertilizer resulted in considerable change in pH and electrical conductivity(EC) value compared to other liquid fertilizers which have microorganisms additives. In addition, it was appeared that the dry yeast-added treatment had higher $NH_4-N$ concentration than other treatments. Addition of molasses resulted in low pH compared to the control which has no additives. The EC, concentration $NH_4-N$ and $P_2O_5$ were not significant difference according to addition of molasses. The pH and $NH_4-N$ concentration in liquid fertilizer containing 20% of fish meal was highest after fermentation process, and EC value increased as the content of fish meal increase. When Cucumber was cultivated using liquid fertilizer, there was no difference in growth between fish meal liquid fertilizer treatment and chemical fertilizers treatment. However, there was a difference in yield according to the supply amount of nitrogen during the growing season.

• The Korean Journal of Food And Nutrition
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• v.18 no.4
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• pp.302-308
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• 2005

To examine the difference in each ingredient between the yeast strain and two raspberry kinds (Rubus crataegifolius Bunge(RCB), Rubus coreanus Miquel(RCM)) in the making of raspberry wine, five active dry yeasts were selected. Regarding the RCM ethanol content, the raspberry wine fermented by Lalvin Wl5 was the highest, while those fermented by Prise de Mousse were the lowest. The pH of the RCM was $3.58\~3.63$, and Montrachet was the highest one of total acidity. In the case of nonflavonoid phenols, the RCM fermented by Montrachet was the highest one, and in the case of flavonoid phenol and total phenol, the RCM fermented by Epernay II was the highest. The content of organic acid in RCM were highest in the following order: citric acid > oxalic acid > malic acid, and tartaric acid was not detected at all. The average content of malic acid in RCM after malolactic fermentation was reduced by almost $65.5\%$, and the RCM fermented by Prise de Mousse, after malolactic fermentation, was $73.3\%$. This latter was the highest, while the RCM fermented by Epernay II was the lowest, at $59.1\%$.

• The Korean Journal of Food And Nutrition
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• v.17 no.4
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• pp.450-457
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• 2004

In wine making, to perform yeast culture effectively, which is the most important factor, 5 strains of representative active dry yeasts were selected : Montrachet, Pasteur Champagne, Epernay II, Prise do Mousse, Lalvin W15. The results about fermentation properties were as follows. After 1 day of fermentation, the ethanol contents of Lalvin W15 wine and Montrachet wine were 5.4% and 4.0%. After 2 days of fermentation, the ethanol content of Lalvin W15 wine was 9.2%, which is the highest degree among all experimental groups. As for the content of sugar solution, the wine fermented by Lalvin W15 was the highest one. In acidic solution, fermentation activity of Prise de Mousse, Lalvin W15, Montrachet were highest degrees and Red wine fermentation activity of Prise de Mousse has shown the highest degree in its fermentation activity, if only initial SO$_2$ amounts were 200 ppm. In regard to the foaming tendency during fermentation, the size of foams in Montrachet was big and the amount of foams was a lot. The change in Brix during the fermentation became evident after two days. The Brix of Montrachet wine and Lalvin W15 wine was 3.0, a high initial fermentation speed. After 10 days of fermentation, total acidity of Lalvin W15 wine was 0.99g/100m1, the highest degree. After 3 days of fermentation, the ethanol content of Lalvin W15 wine was 7.4%, the highest degree. But after 9 days of fermentation Epernay II showed the higher ethanol concentration to 13.8%.