• Korean Journal of Food Science and Technology
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• v.4 no.2
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• pp.100-105
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• 1972

This experiment was conducted to investigate the combined effects of radiation and antiseptics on the keeping qualities of pork sausage, which was treated with potassium sorbate and AF-2(2-(-2-furyl)-3-(5-nitro-2-furyl)-acrylamide), and then followed by gamma radiation of 0.25, 0.5, and 0.75 Mrad. Amounts of treated antiseptics were a quarter, half, and full levels of their maximum permissible concentration. Irradiated and unirradiated sausages were stored for 50 days at $5^{\circ}C\;and\;25^{\circ}C$, and their changes in rancidity, volatile basic nitrogen, bacterial counts, pH, and sensory analysis were examined during the storage period. The results obtained are as follows: 1) Preservative effects of antiseptics were manifested at cold storage; antiseptics treatment of a quarter-level and unirradiation following low-temperature storage showed the same good keeping qualities as the combined treatment of full-level antiseptics and radiation of 0.25 Mrad following high-temperature storage. 2) There did not appear to recognize irradiation-odor, while color and odor were deteriorated intensively by storage temperature. Sausage irradiated with 0.75 Mrad has shown slightly noticeable off-odor at the end of storage at $25^{\circ}C$. 3) The most suitable radiation dose was considered to be 0.5 Mrad, which could extend the storage life about $2{\sim}3$ times longer than untreated.

• Korean Journal of Food Science and Technology
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• v.34 no.4
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• pp.565-569
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• 2002

This study was carried out to estimate the effects of preservatives (alcohol, adipic acid) and heat treatment $(40^{\circ}C,\;60^{\circ}C)$ for the prolongation of shelf-life on low-salt Kimchi. Low-salt Kimchi was prepared with salt replacements (NaCl 50%, KCl 36%, $MgSO_4$ 10%, $CaSO_4$ 3%, glutamic acid 0.2%). Chemical characteristics and microbiological parameters were monitored during fermentation at $20^{\circ}C$. When three kinds of preservative which were alcohol 2.0%, adipic acid 0.1% and their mixture were added to low-salt Kimchi, shelf-life of them were prolonged. To extend the shelf-life of low-salt Kimchi, when the heat treatment at $40^{\circ}C$ and $60^{\circ}C$ were tried, heat treatment at $60^{\circ}C$ was superior than at $40^{\circ}C$. In sensory evaluation of low-salt Kimchi, the control was showed the best quality in the overall acceptability. And low-salt Kimchi treated at $40^{\circ}C$ showed the most similar characteristics to the control Kimchi.

• Journal of Animal Science and Technology
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• v.65 no.1
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• pp.225-243
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• 2023

Large amounts of additives are used during meat product processing to maintain product quality and shelf life. With the growing interest in healthy foods, natural plant-based additives are being used as alternatives to synthetic additives. In this study, six types of natural extracts with excellent antibacterial activity were selected, and their antibacterial and antioxidant activities against four types of pathogens were evaluated in various combinations. In addition, the pH, color, amount of thiobarbituric acid reactive substances (TBARS), and growth of pathogenic microorganisms were analyzed during the storage of sausages treated with various combinations of these extracts. The natural extract mixtures exhibited different antibacterial activities, depending on the combination. Compared to grapefruit seed extract, a mixture of natural extracts extracted with ethanol (M4) reduced the Escherichia coli content by more than 99.9% after 8 days of storage and slowed the growth of Listeria monocytogenes and Salmonella spp. by more than 80% after 14 days. Compared to untreated (NC) and grapefruit extract (PC)-treated sausages, sausages treated with the natural extract mixtures showed a significant decrease in CIE L^* and an increase in CIE a^* and CIE b^* (p < 0.05). The pH value was significantly lower in sausages containing natural extract mixtures than in the NC and PC sausages (p < 0.05). The natural plant extract mixtures significantly prevented lipid oxidation (p < 0.05). In summary, different types of natural extract mixtures have a synergistic effect when used together, suggesting that natural preservatives can generally inhibit the growth of microorganisms and oxidation of processed meat.

• Journal of Microbiology and Biotechnology
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• v.11 no.4
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• pp.577-584
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• 2001

An antimicrobially active bacterium which was identified as Bacillus brevis, was isolated from kimchi. The antimicrobial activity was found against various Gram-positive and Gram-negative bacteria including some pathogens food-spoilage microorganisms, and some yeast strains. The antimicrobial activity was especially strong against Bacillus anthracis and Shigella dysenteriae. The strong activity was observed during an early stationary phase in the culture when incubated at $37^{\circ}C$ with initial medium pH of 6.8. The antimicrobial activity was found to be stable at $90^{\circ}C$ for 30 min and in the pH range of 3-11, and it was insensitive to organic solvents including acetone, acetonitrile, ethanol, and methanol. Analysis of the bacterocin on tricine-sodium dodecyl sulfate-polyacrylamide gel suggested a molecular mass of approximately 4.5-6.0 kDa. The antimicrobial substance was characterized as a bacteriocin, because of its proteinaceous nature and low molecular weight. The bacteriocin could potentially be used as a food preservative, because of its thermostable property and broad antimicrobial spectrum.

• Food Science and Preservation
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• v.6 no.2
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• pp.245-254
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• 1999

Traditionally, lactic acid bacteria(LAB) is microorganism that has been used for food fermentation. Bacteriocinogenic culture and by-products of lactic acid bacteria have the antimicrobial effect. The antimicrobial effect of lactic acid bacteria enable to extend the shelf life of many foods through fermentation processes. Therefore, a lot of investigation of antimicrobial compounds from LAB have been studied on the effect of foods preservation of fish, meat, dairy product, refreserated nonfermentive food and so on. However a little research on the effects of LAB in fruit and vegetables preservation has been reported. In this study, effectiveness of LAB as a quality preservative in fruit and vegetables storage were reviewed.

• Food Science of Animal Resources
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• v.37 no.6
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• pp.793-798
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• 2017

Salt is an essential ingredient for cheese production, and it influences various aspects of cheese, including the shelf life, enzyme activity, flavor, casein hydration, and microbial proliferation during ripening. Several consumers avoid cheese with high salt content, mainly due to health problems such as hypertension, cardiovascular disease (CVD), stroke, and heart attacks. Salt has been commonly used for several purposes in cheese production, including for obtaining the required flavor and texture, for its preservative properties, and as a taste enhancer. However, salt usage has been opposed by the public and governmental bodies, who have been advised by health authorities that salt should be reduced or avoided in cheese for healthier life. However, salt replacement or reduction in cheese manufacturing requires formulation of intensive strategies. This review provides information about several strategies and innovations for reduction and replacement of salt in cheese manufacturing without seriously affecting the quality, microbial safety, and sensory properties of cheeses.

• Preventive Nutrition and Food Science
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• v.22 no.2
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• pp.144-148
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• 2017

Sulfites are used as food preservatives and excessive sulfite might disturb the body systems including the brain. Curcumin shows protective effects on the nervous system toxicity. The present study aimed to evaluate the protective role of curcumin in sulfite-induced anxiety in rats. Male rats were divided into five groups. The rats in groups I to V received distilled water (vehicle of sulfite, 1 mL/d), olive oil (vehicle of curcumin, 1 mL/d), curcumin (100 mg/kg/d), sulfite (25 mg/kg/d), and sulfite+curcumin, respectively, by daily gastric gavage for 8 weeks. At the end of 8 weeks the rats were tested in the elevated plus-maze for anxiety. The results showed that concomitant treatment of curcumin during sulfite consumption prevented the reduction of the time spent in the open arm and entrance to the open arm (the indexes of anxiety). Besides, an increase was found in motor activity of the rats in the sulfite+curcumin group compared to the sulfite-treated animals. Exposure of sulfite in rats can induce anxiety, and curcumin can act as an anti-anxiety agent.

• Food Science and Biotechnology
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• v.18 no.5
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• pp.1301-1304
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• 2009

Macelignan is a bioactive compound isolated from nutmeg (Myristica fragrans Houtt.) which has been traditionally used for the food and pharmaceutical purposes. In this study, the activities of macelignan against vegetative cells and spores of Bacillus cereus were evaluated in vitro. Our results showed that the vegetative cells of B. cereus were significantly inhibited in growth by macelignan with minimum inhibitory concentration (MIC) of $4{\mu}g/mL$. The vegetative cells of B. cereus were completely killed with minimum bactericidal concentration (MBC) of $8{\mu}g/mL$ of macelignan. Killing time of macelignan against vegetative cells of B. cereus was very fast; endpoint of macelignan was reached after 4 hr of incubation at $4{\times}MIC$. Macelignan inactivated more than 3-log (99.9%) of spores/mL of B. cereus at the concentration of $100{\mu}g/mL$. Macelignan was found to be effective against vegetative cells and spores of B. cereus. These results suggest that macelignan might be good to be developed as a food preservative.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.1
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• pp.100-106
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• 1999

Use of chemical preservative for controlling harmful microorganisms in food products has been debated due to public concerns about food quality because of perceived toxic and carcinogenic potential. Thus, use of non toxic natural antimicrobial agents has become essential. This study was investigated to determine the antimicrobial activity of water or ethanol extract of commercially available tea, and of solvent fractionated ethanol extracts obtained from steamed green tea. Both of water and ethanol extracts of green tea(steamed or roasted), oolong tea and black tea exhibited strong antimicrobial activity against gram positive and negative bacteria, but not effective against yeast and mold. Also, antimicrobial activity of ethanol extract of 4 different kinds of tea was stronger than that of water extract. Among 4 different tea, ethanol extract of steamed green tea was further fractionated. One thousand g/disk buthanol extract had the strongest antimicrobial activity against bacteria and mold. The concentration of the antimicrobial activity of buthanol extract in tested microorganisms ranged from 125~1000 g/disk except for Rhizopus javanicus. Antimicrobial activity of buthanol extract of steamed green tea was not destroyed by heating at 100oC for 60 min and at 121oC for 15 min, which is very stable over heat treatment. The inhibitory effect of the buthanol extract on the growth of Listeria monocytogenes and Staphylococcus aureus was investigated. Growth of both strains was started in the presence of 250 and 500 g/ml after 12 and 24 hour respectively, whereas complete inactivation of both strains was occurred in the presence of 1000 g/ml.

• Food Science of Animal Resources
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• v.36 no.3
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• pp.427-434
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• 2016

Benzoic acid is occasionally used as a raw material supplement in food products and is sometimes generated during the fermentation process. In this study, the production of naturally occurring yogurt preservatives was investigated for various starter cultures and incubation temperatures, and considered food regulations. Streptococcus thermophilus, Lactobacillus acidophilus, Lactobacillus delbrueckii subsp. bulgaricus, Lactobacillus rhamnosus, Lactobacillus casei, Lactobacillus paracasei, Lactobacillus reuteri, Lactobacillus plantarum, Bifidobacterium longum, Bifidobacterium lactis, Bifidobacterium bifidum, Bifidobacterium infantis, and Bifidobacterium breve were used as yogurt starter cultures in commercial starters. Among these strains, L. rhamnosus and L. paracasei showed the highest production of benzoic acid. Therefore, the use of L. rhamnosus, L. paracasei, S. thermophilus, and different incubation temperatures were examined to optimize benzoic acid production. Response surface methodology (RSM) based on a central composite design was performed for various incubation temperatures (35-44℃) and starter culture inoculum ratios (0-0.04%) in a commercial range of dairy fermentation processes. The optimum conditions were 0.04% L. rhamnosus, 0.01% L. paracasei, 0.02% S. thermophilus, and 38.12℃, and the predicted and estimated concentrations of benzoic acid were 13.31 and 13.94 mg/kg, respectively. These conditions maximized naturally occurring benzoic acid production during the yogurt fermentation process, and the observed production levels satisfied regulatory guidelines for benzoic acid in dairy products.