• Preventive Nutrition and Food Science
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• v.17 no.1
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• pp.46-52
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• 2012

This study was performed to investigate the effects of pre-treatment and storage temperature and periods on the quality characteristics of ginger paste. The pH of the ginger paste remained constant during room temperature storage but increased with prolonged refrigerated storage periods. During five months of frozen storage, regardless of pre-treatment, the pH of most of the samples decreased slightly and then remained constant. In the color value of ginger paste stored at room temperature, the samples with and without chemical additives changed in color more prominently than fermented or pasteurized samples. Intriguingly, the color value for samples containing chemical additives changed more dramatically when stored under refrigerated conditions. However, the L, a, and b values of samples stored under frozen storage conditions did not change even after ten months. Most of the samples contained glucose and fructose, except for the fermented samples. The free sugar content of samples slowly decreased with increasing storage periods, while the organic acid content generally decreased also, regardless of sample type. Depending on pre-treatment and storage temperature, the gingerol content of the samples was either retained or decreased with prolonged storage time.

• Archives of Pharmacal Research
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• v.25 no.4
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• pp.546-549
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• 2002

The impact of storage conditions on the permeability of porcine buccal mucosa to [$^3H$]water and [$^{14}C$]mannitol was assessed. The fresh pocine buccal tissue (fresh tissue) was obtained by utilizing pig heads within 24 hours of slaughter. The stored and frozen porcine buccal tissues (stored tissue and frozen tissue) were obtained after the storage of the tissue intact in the pig heads at $4^{\circ}C$ or -$20^{\circ}C$, respectively, for 24 h. The results demonstrated that the barrier properties of the porcine buccal mucosa were maintained with regard to [$^3H$]water permeability when stored at $4^{\circ}C$ for 24 h. However, freezing the tissue resulted in tissue damage illustrated by a significant increase in [$^3$H]water permeability. [$^{14}C$]Mannitol does not appear to be a suitable model solute to assess the ex vivo permeability of porcine buccal mucosa due to its extremely low permeability.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.4
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• pp.356-362
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• 1986

This experiment was designed to evaluate effects of freezing and frozen storage on survival of sanitary indicative bacteria in seafoods. Culture of bacteria such as Escherichia coli type I, Citrobacter freundii type I, Klebsiella aerogenes type I and Streptococcus faecalis was inoculated into homogenates of pollack, shrimp, and sardine frozen in a contact plate freezer at $-40^{\circ}C$ and chest freezer at $-20^{\circ}C$, stored at $-20^{\circ}C$, and then survival of the inoculated bacteria was determined over a period of 95 days. Coliform group was highly sensitive to freezing and frozen storage showing survival of about $2\%$ after 95 days of frozen storage at $-20^{\circ}C$, whereas Streptococcus faecalis was relatively resistant with $20\%$ survival rate. The sanitary indicative bacteria count was rapidly decreased in the early stage of frozen storage revealing 90 to $95\%$ loss of coliform group and 40 to $70\%$ loss in case of Streptococcus faecalis after 10 days storage. In determining recovery rate, most probable number (MPN) method gave more reproducible recovery of the tested strain than did the selected agar plate method.

• Journal of the Korean Dietetic Association
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• v.13 no.4
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• pp.345-356
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• 2007

The purpose of this study was to investigate utilization and storage management practice of the frozen and refrigerated foods in school foodservice. 222 dietitians employed in school foodservice were surveyed. In school foodservice, the refrigerated stock farm products and seafoods (78.3%) were more used rather than frozen products (47.5%). According to school foodservice characteristics, the refrigerated meats including dairy products were more frequently used in elementary and middle schools than high school foodservice. On the other hand, the foodservice in high school used more frozen seafoods and processed foods than elementary school did. The data also showed a tendency for the contracted foodservice using more frozen meats and seafoods rather than refrigerated products when comparing with the self-operated foodservice. In terms of receiving conditions, storage methods and storage time, the result indicated that frozen or refrigerated products were often delivered at inappropriate temperature. Especially some products which were needed to be shipped and stored at refrigerated temperature such as mollusks, were delivered and kept at room temperature. The most frequently used thawing method were running water (56.9%), however, the frozen products were often sitted at room temperature for the purpose of thawing. According to the results, several inappropriate handling processes for frozen and refrigerated products were found in school foodservice. In order to improve handling process for frozen and refrigerated products, recognition of food handlers' weakness about storage and distribution, development of radical standards for receiving conditions, storage and thawing methods should be debated.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.6
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• pp.763-770
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• 1993

To investigate the quality changes during frozen storage, top shell, Omphalius pfeifferi capenteri, was stored at -18$^{\circ}C$, -$25^{\circ}C$ and -3$0^{\circ}C$ immediately after shelling and water holding capacity, protein composition and histological features were examined with the lapsed period of the storage. During the storage period, amount of free drip was increased with higher frozen temperature and longer frozen period, but with the longer storage period, the lower water holding capacity was observed. The extractability and composition of muscle protein, sarcoplasmic protein and stroma protein were rather stable regardless of frozen temperature and frozen storage period. However, the extractability of myofibrillar protein was decreased with higher frozen temperature and longer frozen storage period. On the changes of muscle tissue structure, following points were observed. 1) In the muscle tissue structure of fresh sample, fine muscle fiber was closely distributed all over the tissue regardless of cross and longitudinal section. 2) In tissue structure under frozen state, it was observed that ice crystals apparently grew with the higher storage temperature. Empty spaces between muscle bundles which wee formed by aggregations of muscle fiber were observed after 3 months storage at -18$^{\circ}C$ . 3) Tissue structure in thawed state was restored satisfactorily after 1 month storage regardless of storage temperature. After 3 months storage at -3$0^{\circ}C$, muscle tissue was well restored, but at -18$^{\circ}C$, empty spaces were apparent due to incomplete restoration.

• Food Science of Animal Resources
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• v.21 no.4
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• pp.292-299
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• 2001

Chicken surimi from mechanically deboned chicken meat was prepared with 0.2% oleoresin spices such as rosemary, thyme, sage, mace, marjoram, and bay. Samples were stored at -18$\^{C}$ for 14 weeks to observe quality change including lipid oxidation, color and textural properties. The pH of surimi decreased from pH 7.44∼7.58 stored at 1 day to pH 7.03∼7.13 stored at 14 weeks. The control surimi showed higher level of pH during storage periods. Color stabiilty of surimi decreased during frozen storage both in control and oleoresin added surimi. Control surimi comparatively maintained higher color stability during frozen storage because of higher L* and a* values, and lower b*. On the contrary, the marjoram addition significantly decreased L* and a* value, and increased b* value compared with other oleoresins. Therefore, the color of surimi seems to be affected original color of oleoresin spice itself. Gel strength showed loser level in oleoresin added surimi than control surimi. Oleoresin spices inhibited lipid oxidation significantly because less thiobarbituric acid-reactive substance(TBARS) were accumulated in oleoresin added surimi than control surimi. Sage was the most effective in minimizing lipid oxidation in frozen surimi as TBARS of sage added surimi stored for 14 weeks maintained only 42% compared with that of control. In conclusion, the 6 kinds of oleoresin in this experiment retarded oxidative rancidity in chicken surimi but there was no beneficial effect on the surface color and gel strength.

• Korean Journal of Veterinary Research
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• v.15 no.2
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• pp.207-213
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• 1975

Skimmed goat milk heated at $92^{\circ}C$ for 10 minutes was used as a basal extender for bull semen. The extenders for liquid semen were prepared by adding simultaneously at various ratio of 5% dextrose solution and egg yolk to skimmed goat milk. After bull seven was diluted with the extenders at the rate of 20 million spermatozoa per ml of the extenders. The extenders were stored at $5^{\circ}C$ and the survival rates of spermatozoa were examined at 4 and 24 hours, and 3, 5 and 7 days after dilution. The extenders for frozen semen were prepared by adding various ratlo of glycerol to skimmed goat milk containing 20 parts of 5% dextrose solution and 3 parts of egg folk to 77 parts of skimmed goat milk. After bull semen was diluted with the extenders at the rate of 40 million spermatozoa per ml of the extenders, the extenders were frozen in liquid nitrogen tank. The frozen extenders were thawed at $40^{\circ}C$ for 2 minutes, and the revival rates of the spermatozoa in the extenders were examined. These thawed extenders were stored at $5^{\circ}C$ and the survival rates of the spermatozoa were examined at 10 minutes and 24 hours and 3 and 5 days after thawing. The results obtained were as follows: 1. Among the extenders stored at $5^{\circ}C$, the survival rate of the sperm was the highest in the extender including 20 parts of 5% dextrose solution and 3 parts of egg yolk to 77 parts of skimmed goat milk, and the survival rate was significantly higher that of the spermatozoa in egg folk-2.9% sodium citrate (1 : 4) extender. (P<0.05) 2.Among the extenders frozen in liquid nitrogen tank, the revival rate of the spermatozoa was the highest in the extender containing 7ml of glycerol per 100ml of the extender with consisted of 77 parts of skimmed goat milk, 20hparts of 5% dextrose solution and 3 parts of egg yolk, and the revival rate was significantly higher than that of the spermatozoa in egg yolk-2.9% sodium citrate (1 : 4) extender containing 8ml of glycerol per 100ml of the extender (p<0.01). 3. Among the extenders stored at $5^{\circ}C$ after thawing, the survival rate of the spermatozoa was the highest in the extender containing 7ml of glycerol per 100ml of extender which consisted of 77 parts of skimmed goat milk, 20 parts of 5% dextrose solution and 3 parts of egg yolk, and the survival rate was significantly higher than that of the spermatozoa in egg yolk -2.9% sodium citrate (1 : 4) extender containing 8ml of glycerol per 100ml of the extender (p<0.01).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.2
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• pp.121-126
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• 2018

The purpose of this study was to assess bacteriological hazards in the following 7 kinds of minimally processed shellfish products purchased from Korean seafood retail outlets: raw oysters stored with seawater in polyethylene bags, frozen oysters, raw mussels, frozen mussels, boiled mussels, raw short-necked clam, and frozen short-necked clams, obtained from Korean seafood retail outlets. The total coliform and Escherichia coli counts determined in all samples were detected below regulation limit of the Korean government guidelines (Food Code). In addition, the high-risk bacterial pathogens, Listeria monocytogenes, Salmonella spp., and E. coli O157:H7 were not detected in any samples. Low-risk pathogens such as Staphylococcus aureus and Vibrio parahaemolyticus were detected at levels above $1.0{\times}10^2$ colony forming unit (CFU)/g in some minimally processed shellfish products. Notably, S. aureus was detected in all samples. Raw oysters stored with seawater in polyethylene bags, frozen oysters, and boiled blue mussels are commonly ingested without heating, and therefore these minimally processed shellfish products pose bacteriological hazards. The detection of S. aureus in all shellfish products, an organism indicative of poor personal hygiene, which can grow and multiply during distribution, indicates the necessity of improving the food safety of minimally processed shellfish products.

• Preventive Nutrition and Food Science
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• v.6 no.4
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• pp.211-215
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• 2001

The packaging effect on physicochemical changes in irradiated sausage stored at -2$0^{\circ}C$ was studied. Emulsion-type cooked pork sausage was made with (156 ppm) or without NaNO$_2$ (0 ppm), and packaged in three different conditions such as aerobic, vacuum and $CO_2$ (100%). The samples irradiated at 0, 5 and 10 kGy absorbed dose, and the total number of microorganisms, lipid oxidation, color and texture were analyzed during frozen storage at-2$0^{\circ}C$. Irradiation of the sausage at 10 kGy completely controlled microbial growth during storage. An NaNO$_2$ addition to the sausage significantly reduced lipid oxidation, and the TBARS value of the sausage with aerobic packaging was higher than that with the vacuum and $CO_2$ packaging. The NaNO$_2$ addition increased Hunter color a-value dramatically, but no packaging effect was found (p > 0.05). Irradiation influenced shear values resulting in lower shear values in 10 kGy-irradiated sausages with aerobic packaging, and $CO_2$ packaged sausage showed comparatively lower shear value than other packaging methods. From the results, vacuum or $CO_2$ (100%) packaging were better than aerobic packaging for frozen stored pork sausage, especially far microbial quality and lipid oxidation.

• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.536-540
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• 1988

Effects of blanching time, chemical dipping, freezing method and storage period on texture, color and yield of frozen whole and sliced mushrooms were investigated, and the results are summarized as follows; Frozen whole mushrooms blanched for 5min. had markedly tougher texture than mushrooms blanched for 1 or 2 minutes. As the storage time of frozen mushrooms increased from 3 to 6 months, shear press values increased very significantly. The texture of Freon frozen and plate frozen mushrooms was similar after 3 months storage. Blanching time did not affect texture of frozen sliced mushrooms significantly, but storage time did. The results of sensory evaluation for texture were in good agreement with shear press values. Chemical dipping methods were effective in maintaining desirable color of frozen whole and sliced mushrooms stored for 3 months. The yield of frozen whole mushrooms was significantly increased by shortening blanching time in combination with chemical dipping. Sliced mushrooms required at least 2 min. blanching, to avoid excessive breakage in mechanical slicing operation, for better yield.