• Asian-Australasian Journal of Animal Sciences
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• v.30 no.9
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• pp.1278-1284
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• 2017

Objective: To assess the potency of calcium propionate (CAP) used as silage additive, an experiment was carried out to evaluate the effect of CAP on the nitrogen transformation, fermentation quality and aerobic stability of alfalfa silages. Methods: Alfalfa was ensiled with four levels of CAP (5, 10, 15, and 20 g/kg of fresh weight [FW]) in laboratory silos for 30 days. After opening, the silages were analyzed for the chemical and microbiological characteristics, and subjected to an aerobic stability test. Results: The increasing proportion of CAP did not affect pH, lactic acid (LA) concentrations and yeast counts, while linearly decreased counts of enterobacteria (p = 0.029), molds (p<0.001) and clostridia (p<0.001), and concentrations of acetic acid (p<0.001), propionic acid (p<0.001), butyric acid (p<0.001), and ethanol (p = 0.007), and quadratically (p = 0.001) increased lactic acid bacteria counts. With increasing the proportion of CAP, the dry matter (DM) loss (p<0.001), free amino acid N (p<0.001), ammonia N (p = 0.004), and non-protein N (p<0.001) contents were linearly reduced, whereas DM (p = 0.048), water soluble carbohydrate (p<0.001) and peptide N (p<0.001) contents were linearly increased. The highest Flieg's point was found in CAP10 (75.9), represented the best fermentation quality. All silages treated with CAP improved aerobic stability as indicated by increased stable hours compared with control. Conclusion: The addition of CAP can suppress the undesirable microorganisms during ensiling and exposure to air, thereby improving the fermentation quality and aerobic stability as well as retarding the proteolysis of alfalfa silage. It is suggested that CAP used as an additive is recommended at a level of 10 g/kg FW.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.3
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• pp.463-468
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• 2004

This study was conducted to determine the antimicrobial effect of leaf, bark and xylem of 6 kinds of Quercus spp. against food borne disease bacteria. All of the samples tested showed the antimicrobial effect against food borne disease bacteria. Bacillus cereus, Listeria monocytogenes, and Staphylococcus aureus was more sensitive than gram negative bacteria such as Salmonella typhimurium and Escerichia coli O157:H7, but no antimicrobial activity was observed against yeast and molds. Based on antimicrobial activity for kinds of Quercus spp., the antimicrobial activities of Quercus aliena Blume, Quercus mongolica Fisch, and Quercus dentata Thunb were stronger than those of Quercus variebilis Blume, Quercus serrata Thunb, and Quercus acutissima Carruth. In the meantime, the ethanol extract of Quercus spp. leaves showed the strongest antimicrobial activity compared to that of bark and xylem. Especially, the ethanol extract of Quercus aliena Blume leaf showed the strongest antimicrobial effect against foodborne disease bacteria among 6 kinds of Quercus spp.

• Journal of Microbiology and Biotechnology
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• v.24 no.8
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• pp.1088-1095
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• 2014

A systematic investigation was performed on the bacterial, Bacillus, fungal, and yeast communities of the three types of Daqu (mechanically prepared, manually prepared, and mixed prepared) used in Baiyunbian Company by reconditioning PCR-denaturing gradient gel electrophoresis (PCR-DGGE). The DGGE results showed that the microbes in the three types of Daqu were mainly thermotolerant and thermophilic microbes, and the most dominant bacterial species were Bacillus and Virgibacillus, followed by Lactobacillus and Trichococcus. Furthermore, the dominant fungi were found to be molds, such as Rasamsonia, Penicillium, Aspergillus, and Monascus, and the dominant yeasts were Saccharomyces cerevisiae, Saccharomycopsis fibuligera, Pichia anomala, and Debaryomyces hansenii. In general, the three types of Daqu showed slight differences in microbial communities, and the Shannon indexes (H') of the manually prepared and mechanically prepared Daqu were similar. The results suggest that mechanically prepared Daqu can replace manually prepared Daqu in liquor production, and this research provides useful information for liquor production and process improvement.

• Food Science and Biotechnology
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• v.14 no.6
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• pp.752-757
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• 2005

Changes in milk quality during storage of extended shelf life milk (ESL milk) and non-ESL milk were evaluated. No significant differences were observed between ESL and typical ultra high temperature-treated (UHT) milk in physicochemical properties including non-casein nitrogen (NCN) content, whey protein nitrogen index (WPNI), and L-ascorbic acid content. Low temperature and long time-treated milk (LTLT milk) had significantly higher NCN content and WPNI than those of UHT milk. In terms of microbial quality, yeast, molds, coliforms, and other bacteria were not detected in ESL milk during entire storage (21 days after expiration date) period at 4 and $25^{\circ}C$, while LTLT milk was more susceptible to microbial infection. Rats fed ESL milk resulted in significantly higher body weight, average daily gain, and feed efficiency than those given UHT milk. These results suggest ESL milk maintains better microbial quality than typical UHT milk, particularly during storage under extended refrigeration and at high temperature.

• Food Science and Preservation
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• v.7 no.1
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• pp.12-18
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• 2000

As am economical and effective way of antimicrobial film fabrication , antimicrobial agents were coated on the LDPE film with a binder mediu. the fabricated films were then applied tomodified atmosphere packaging of fresh strawberries. A binder of polyamide was selected for the coating medium, based on the stability in water. 1% grapefruit seed extract-coated film showed the antimicrobial activity on the plate media against EScherichia coli, Staphylococcus aureus, bacillus subtilis , Bacillus cereus, Leuconostoc mesenteroides, Micrococcus flavus, Saccharomyces cerevisiae, while one with 10% Coptis chinesis extract inhibited only M. 림편 and one coated with 10% rheum palmatum extract did not inhibit any of 10 strains tested. The packages of fresh strawberries by using antimicrobial agents-coated films created the gas compositions of O2 1.4-5.5% and CO2 5.7-7.9%, and contributed to reduced growth of total aerobic bacteria and yeast/molds on the produced. However, their lower microbial count was not correlated directly with the reduced decay of the fruits.

• Korean Journal of Food Science and Technology
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• v.37 no.1
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• pp.129-133
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• 2005

Aqueous chlorine dioxide and citric acid treatment was introduced to insure microbial safety of minimally processed and refrigerated (MPR) salad. Salad samples were treated with 50 ppm chlorine dioxide and 1% citric acid. Chemical treatment decreased total aerobic bacteria, yeast and molds, E. coli, and Listeria by 3.75, 3.47, 3.41, and 3.38 log cycles, respectively, and polyphenoloxidase activity of MPR salad by 49.73%. Plain water washing of salads did not effectively decrease microbial growth. These results indicate appropriate chemical treatment provides microbial safety and quality control in MPR salad during marketing.

• Journal of the East Asian Society of Dietary Life
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• v.26 no.3
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• pp.230-236
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• 2016

The study was carried out to evaluate the quality of commercial pork and beef jerky at a market in Korea. The amount of food additives, place of origin, meat content, microbiological and physicochemical characteristics were investigated in 46 different jerky samples. Meat contents of pork and beef jerky were 75.2~94.0% and 80.0~95.6%, respectively. Food additives, including sodium nitrite, potassium sorbate, and sodium erythorbate were mainly used in jerky. Pork jerky was processed from domestic pork, and beef jerky was mostly processed from imported beef from the USA, Australia, or New Zealand. Pork jerky contained $23.82{\pm}5.74%$ moisture, $37.86{\pm}7.05%$ crude protein, $6.16{\pm}4.91%$ crude fat, and $4.6.87{\pm}1.76%$ crude ash. Beef jerky contained $26.64{\pm}5.21%$ moisture, $41.36{\pm}3.50%$ crude protein, $4.67{\pm}3.46%$ crude fat, and $7.21{\pm}1.91%$ crude ash. Water activity (Aw) of pork jerky was $0.73{\pm}0.09$ while that of beef jerky was $0.78{\pm}0.08$. Volatile basic nitrogen (VBN) content to jerky was 7.1~36.0 mg/100 g. There was no significant difference in the physicochemical composition of meat type (p<0.05). Coliform, Escherichia coli and Staphylococcus aureus were not detected in pork or beef jerky, whereas yeast and molds were detected below $1.2{\times}10^1CFU/g$ in beef jerky samples.

• Journal of the East Asian Society of Dietary Life
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• v.25 no.2
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• pp.326-332
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• 2015

Makjang is a kind of Korean traditional short-term fermented soybean paste. The purpose of this study was to evaluate the compositions of free sugars, organic acids and free amino acids as well as microbial counts of six kinds of Makjang. Commercial Makjang from different regions (Kangwon-do, Choongchung-do and Kyungsang-do) were used. The major free sugars of samples were glucose (0.15~3.97%) and maltose (0.01~0.54%), whereas sucrose (0.02%) was detected only in M4 and fructose only in M1 and M2. The major organic acids were citric acid (0.16~3.09%), malic acid (0.06~0.23%) and succinic acid (0.01~0.11%). The total content of free amino acids ranged from 0.02 to 8.74 mg/g, and major amino acids were detected in the order of glutamic acid, leucine, alanine and aspartic acid. Numbers of viable cells of bacteria as well as yeast and molds were $7.8{\times}10^4{\sim}4.8{\times}10^5$ and $8.1{\times}10^3{\sim}3.6{\times}10^4$, respectively. The results of the sensory evaluation showed that over-all preference of Kyungsang-do Makjang was higher than others. Consequently these results provide better information for standardizing and improving quality and functional activity of commercial Makjang.

• Food Science and Preservation
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• v.15 no.3
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• pp.385-389
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• 2008

The effects of high vanillin concentration on fresh-cut apples treated with NatureSealTM were investigated Apples were sliced, treated with 6% NatureSealTM or 6% NatureSealTM + 120 mM vanillin, packaged in polyethylene bags, and stored for 3 weeks at 4C. The L value, soluble solid level and titratable acidity of fresh-cut apples treated with NatureSealTM + 120 mM vanillin during storage were lower than those of fresh-cut apples treated with NatureSealTMonly; the growth of total aerobic bacteria, yeast and molds were also more inhibited in fresh-cut apples treated with NatureSealTM + 120 mM vanillin. These results show that the addition of 120 mM vanillin inhibits the growth of microorganism but 1m detrimental effects on the quality characteristics of fresh-cut apples treated with NatureSealTM.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.1
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• pp.138-145
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• 2010

The combined effect of 50 ppm aqueous chlorine dioxide ($ClO_2$) or 0.5% fumaric acid with $5 kJ/m^2$ ultraviolet-C (UV-C) on the postharvest quality of "Flamengo" strawberries was examined. After non-thermal treatment, the samples were stored at $4\pm1^{\circ}C$ for 12 days. The combined treatment of fumaric acid/UV-C reduced the initial populations of total aerobic bacteria and yeast and molds in the strawberries by 2.09 and 2.02 log CFU/g, respectively, compared to those of the control. In addition, after 12 days of storage the yeast and molds population in the combined treatment was 1.72 log CFU/g, compared to 5.10 log CFU/g for the control, resulting in a significant decrease of 3.38 log CFU/g. Postharvest treatments used in this study caused negligible changes in the color of the strawberries. Sensory evaluation results indicated that the combined postharvest treatment provided better sensory scores than did the control. In particular, the overall acceptability scores were higher for the combined treatment groups after 5 days of storage. These results suggest that combined treatment of either 50 ppm $ClO_2$ or 0.5% fumaric acid with $5 kJ/m^2$ UV-C can be useful for maintaining the quality of strawberries.