• The Korean Journal of Food And Nutrition
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• 제27권2호
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• pp.183-193
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• 2014

This study is conducted to evaluate the effects of gamma irradiation (0.4, 0.6, 0.8, 1 and 1.5 kGy) on the microbiological, physicochemical and sensory qualities of imported oranges during storage at $20^{\circ}C$ for 15 days. Total aerobic bacteria and yeast/mold counts in non-irradiated oranges increase significantly with increasing storage time. Irradiation has effects on the reduction of microorganism of dose-dependent oranges. The vitamin C contents decrease significantly according to dose-dependent manners and storage times after the gamma irradiation. Sensory evaluation decreases according to dose-ependent manners and storage times, excluding the color. The results suggest that gamma irradiation is effective for ensuring the microbiological safety, but the irradiated oranges more than 1 kGy are not good for physicochemical and sensory qualities. Therefore, irradiated samples of 0.4~0.6 kGy are considered as the optimum-dose for maintaining quality.

• Korean journal of food and cookery science
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• 제20권2호
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• pp.211-218
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• 2004

The issue of safety and quality of cooked food served at foodservice institutions has brought more attention to food scientists because the foodservice system is growing and becoming more popular in Korea. In order to control the quality and safety of cooked foods, the production and holding methods of foods should be carefully studied and the implications considered by the foodservice industry. Therefore, studies on microbiological, nutritional, physicochemical and sensory quality are essential in this area. The purpose of the present study was to evaluate the chemical and microbial qualities of salads during holding. Several holding temperatures in the range of 5∼26$^{\circ}C$ were used for holding. Chicken salad and ham ＆ cucumber salad exceeded the standard after 30min of room temperature holding after preparation. Quality deterioration increased at higher holding temperatures, which suggested that refrigerator holding is the most desirable.

• Journal of Food Hygiene and Safety
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• 제2권3호
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• pp.97-102
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• 1987

The effects of gamma irradiation on microbiological and physicochemical qualities in raw ingredients (thirteen kinds of cereal grain and their by-product) of mixed feeds were investigated. The total aerobic bacteria counts in the samples were $10^2\;to\;10^6/g$. They were sterlllzed to a undetectable level by 5 to 7 kGy irradiation. Coliforms were contaminated in high levels in all sample, ranging from $10^2\;to\;10^6/g$. They were radiation-llensitive and completely eliminated by irradiation with 3 to 5 kGy. Total fungi, ranging from $10^2\;to\;10^4/g$, mainly osmophiles were identified as Aspergillus and Penicillium. They were eliminated below identification limit by 5 to 7 kGy irradiation. Seven kinds of species, including Aspergillus IkrlJUB. were identified as a potential mycotoxin producers. Physicochemical qualities, such as total amino acid content, total sugar content. TBA value and color difference showed that an optimum dose of irradiation was less detrimental than ethylene oxide fumigation.

• Food Science of Animal Resources
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• 제39권5호
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• pp.804-819
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• 2019

Ezine cheese is a non-starter and long-ripened cheese produced in the Mount of Ida region of Canakkale, Turkey, with a protected designation of origin status. Non-starter lactic acid bacteria (NSLAB) have a substantial effect on the quality and final sensorial characteristics of long-ripened cheeses. The dominance of NSLAB can be attributed to their high tolerance to the hostile environment in cheese during ripening relative to many other microbial groups and to its ability to inhibit undesired microorganisms. These qualities promote the microbiological stability of long-ripened cheeses. In this study, 144 samples were collected from three dairies during the ripening period of Ezine cheese. Physicochemical composition and NSLAB identification analyses were performed using both conventional and molecular methods. According to the results of a 16S rRNA gene sequence analysis, 13 different species belonging to seven genera were identified. Enterococcus faecium (38.42%) and E. faecalis (18.94%) were dominant species during the cheese manufacturing process, surviving 12 months of ripening together with Lactobacillus paracasei (13.68%) and Lb. plantarum (11.05%). The results indicate that NSLAB contributes to the microbiological stability of Ezine cheese over 12 months of ripening. The isolation of NSLAB with antimicrobial activity, potential bacteriocin producers, yielded defined collections of natural NSLAB isolates from Ezine cheese that can be used to generate specific starter cultures for the production of Ezine cheese (PDO).

• Korean Journal of Fisheries and Aquatic Sciences
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• 제52권3호
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• pp.224-231
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• 2019

This study investigated the physicochemical, microbiological, antioxidant, and sensory characteristics of Makgeolli supplemented with 10, 20, and 30% Codium fragile (Cf) during an 8-day fermentation period. The pH and acidity on day 0 were lower in Makgeolli supplemented with Cf (pH 3.55-3.65, acidity 0.26-0.29%) than in the unsupplemented Makgeolli (control) (pH 3.72, acidity 0.23%). The pH and acidity of Cf Makgeolli on day 8 were 3.08-3.12 and 0.67-0.75%, respectively. The sugar content increased steadily until day 4 (8.1-8.5 Brix) and then decreased steadily (6.5-6.8 Brix). The alcohol content increased steadily until day 8 (13.2-14.3%). The pH decreased, acidity increased, and alcohol content increased significantly (all P<0.05), with stepwise increases in fermentation time and Cf concentrations. The lactic acid bacteria counts were 9.28-9.37 log versus 8.18 log in the control. The DPPH (1,1-diphenyl-2-picrylhydrazyl) and ABTS [2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)] radical scavenging activities were higher in Cf Makgeolli (DPPH 74.63-84.64%, ABTS 51.01-64.79%) than in the control (DPPH 30.97%, ABTS 21.21%). Makgeolli supplemented with 10 and 20% Cf had the highest taste, smell, and overall acceptance scores. This study suggests that Makgeolli supplemented with 10 and 20% Cf could be developed due to its good physicochemical and microbiological characteristics, including high antioxidant properties and good consumer acceptance.

• Journal of the Korean Society of Food Science and Nutrition
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• 제26권5호
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• pp.800-806
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• 1997

Effect of temperature on Kakdugi during fermentation was investigated by measuring sensory, physicochemical and microbiological, properties up to 57 days. The diced(2.5$\times$2.5$\times$2.5cm) Chinese radishes(Ra-phanus sativus L.) with other ingredients were fermented under the different temperatures. Kakdugi were stored at 4$^{\circ}C$ after keeping at 2$0^{\circ}C$ for 12 hours(treatment E) from initial fermentation to the end at each temperature on preparation. The pH was decreased to the range of 4.14~4.29 in the initial of pH 5.8, and total acidity was increased 2~4 times more than that of in the initial period (0.24%). And the changes of treatment A, B, and C were nearly constant up to 57 days in the range of 0.80~0.88% (pH 4.1). The changes of vitamin C showed sigmoidal curve, increasing significantly in the palatable period after decreasing gradually in the initial period. The content of vitamin C in treatment E was rapidly decreased, but that of treatment C was kept high content up to 57days. the number of lactic acid bacteria was remarkably increased in palatable period and was gradually decreased thereafter. The scores of aroma, taste, overall acceptability in sensory evaluation during the fermentation was high in order of treatment E, C, D, B and A. The scores of sensory evaluation treatment D and E during fermentation was rapidly decreased, however, treatment A, B and C were maintained. Changes of lactic acid bacteria, and sensory properties, among treatment A, B and C which kept a good quality up to 57 days, had high scores of sensory evaluation, abundant vitamin C in the palatable period. The result showed that Kakdugi fermented at 4$^{\circ}C$ after keeping at 2$0^{\circ}C$ for 36 hours had better taste and quality than those of other treatments.

• Food Science of Animal Resources
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• 제42권4호
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• pp.639-654
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• 2022

The current study investigated the effects of the most suitable modified atmosphere packaging (MAP) on the physicochemical, microbiological, and sensory properties of fermented dry sausages during 45 days of refrigeration (4℃) storage period. Treatments were vacuum-packed (control), 25% CO₂/75% N₂ (MAP1), 50% CO₂/50% N₂ (MAP2), 70% CO₂/30% N₂ (MAP3), and 100% CO₂ (MAP4). All MAP samples regardless of their CO₂ composition significantly (p<0.05) decreased in pH, a_w, total plate count, and lactic acid bacteria count values as compared to the vacuum-package during storage. The Enterobacteriaceae count in all MAP packaging was significantly (p<0.05) lower than the vacuum-packed samples and counts in MAP3 and MAP4 samples were markedly (p<0.05) lower than all other treatments in prolonged storage of 15 and 45 days. Based on the thiobarbituric acid reactive substance content at day 15 and 30 storage time, treatments are ranked as follows: Vacuum-packed>MAP1>MAP2>MAP3>MAP4. The a^* of MAP4 was higher than all other treatments. In the final storage days, no variation was exhibited (p>0.05) among treatments in lactic acid aroma and sourness, and MAP2 samples had the lowest (p<0.05) overall acceptability. The use of MAPs with an increase in the CO₂ from MAP1 to MAP4 samples can help in better microbial inhibition than vacuum package, and 70% CO₂/30% N₂ (MAP3) and 100% CO₂ (MAP4) were effective to maintain several quality parameters (a_w, pH, microbial inhibition, stability against lipid oxidation, and instrumental color traits) and extend the shelf life of dry fermented sausage.

• Food Science and Preservation
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• 제16권2호
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• pp.198-203
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• 2009

We examined the effects of electron-beam irradiation(0.5, 1, 2, or 5 kGy) on microbiological, physicochemical, and sensory quality characteristics of Myungran Jeotgal, Korean fermented seafood, during subsequent storage at $4^{\circ}C$ for 2 weeks. Viable counts of total aerobic bacteria, yeasts and molds, and total coliforms fell, after irradiation, to below detection limits($10^1CFU/g$). The pH of irradiated Myungran Jeotgal was maintained during storage but that of the non-irradiated control decreased. Sensory quality was not affected by electron-beam irradiation, except that color scores in samples irradiated with 2 and 5 kGy were lower than that of the control. Lipid oxidation tended to rise with increased irradiation dose and longer storage periods. The results suggest that electron-beam irradiation can be used to extend the shelf-life of Myungran Jeotgal without apparent quality attribute deterioration. However, means of preventing lipid oxidation resulting from electron-beam irradiation need consideration if irradiation is to find further applications in the food industry.

• Journal of Animal Science and Technology
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• 제57권7호
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• pp.24.1-24.5
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• 2015

The objective of this study was to investigate the physicochemical and microbial quality of loin (m. longissimus dorsi) and top round (m. Semimembranosus) in Holstein veal produced from two slaughter age groups (5 and 8 months of age). A total of 20 Holstein calves were randomly selected from a local cattle farm. The slaughtered cold carcasses were vacuum-packaged. The samples were analyzed for proximate composition and physicochemical analyses and stored for 1, 7, 10, 20 and 30 days for microbiological analyses. Fat and protein contents of loin for the 8 month group were higher than those for the 5 month groups (p < 0.05). For both loin and top round muscles, the pH, cooking loss and the shear force values for the 5 month group was higher than those for the 8 month group (p < 0.05). On the other hands, the water-holding capacity (WHC) for the 8 month group was higher than those for the 5 month group (p < 0.05). In terms of meat color, CIE $L^*$ (lightness) for both muscle were higher in the 5 month group than in the 8 month groups. On the other hands, $a^*$ (redness) were higher in the 8 month group than in the 5 month groups (p < 0.05). Total aerobic counts in all samples remained up to 30 days at values less than 7 log CFU/g. However, there was no significant difference for both muscles between the two age groups. The results indicate that Holstein muscles from the 8 month group had desirable quality properties than those from the 5 month group.

• Food Science and Preservation
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• 제5권1호
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• pp.41-47
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• 1998

Physicochemical properties and microbiological quality chanties were investigated on mixed fruit and vegetable juices (apple, carrot and cucumber) stored at 4$^{\circ}C$ without pasteurization(NT), with light piasteurization (LP; 66$^{\circ}C$, 10 sec) and with full pasteurization(FP; 90$^{\circ}C$, 60 sec). Effects of ultrafiltration (UF) on the changes during storage were also examined. pH, viscosity, a-value and b-value remained relatively constant and all samples revealed Newtonian characterisitics. Total acidity and turbidity tended to increase slightly; however, total vitamin C content and L-value slowly decreased during storage up to about 2 months. During the first 4 weeks storage, soluble solids content slowly increased and then decreased. Mold and Yeast and Bacteria were not detected in LP, UP and UF treated samples during storage studied; however, E. coli were detected after 24 days storage. No distinctive storage effects were found among samples prepared; however, ultrafiltration had a considerable effect on the color and soluble solids content of mixed fruit and vegetable juice.