• Korean journal of food and cookery science
• /
• v.25 no.2
• /
• pp.170-179
• /
• 2009

This study examined effects on shelf-life extension and prevention of starch retrogradation in rye-wheat mixed bread (RWMB) samples prepared with substitutions of 20, 40, 60, and 80% rye sourdough (RSD) as well as a control made with the addition of naturally fermented raisin extract. These effects were investigated using mold growth, water activity, and textural characteristics during a storage period of 8 days at $20^{\circ}C$. The activities of the rye sourdough were examined in terms of pH, total titratable acidity, general bacteria, lactic acid bacteria, and yeast counts. As the incubation time of the sour dough increased, pH decreased, while total titratable acidity increased. General bacteria, lactic acid bacteria, and yeast counts increased with increasing incubation time. Mold grew on the external surface of the control group after 6 days and on the surface of the RSD bread samples after 8 days, respectively. With regard to water activity, the control group had increasing activity as the storage period increased. In addition, the 20, 40, 60, and 80% RSD samples had increasing water activities until the 4th day however, these strongly decreased by the 6th day. In terms of textural characteristics, as the storage period increased, hardness increased, while springiness, cohesiveness, and resilience decreased. There were no significant differences in gumminess among the samples. The control, 20, 40, and 60% RSD samples had decreases in chewiness with increasing storage time, however, the 40% RSD sample did not differ significantly during the storage period. Finally, water activity was negatively correlated with hardness (p<0.05). In conclusion, the results indicate that substituting rye sourdough in rye-wheat mixed bread has a prolongation effect on shelf-life, but no effect on the prevention of starch retrogradation.

• Journal of Bio-Environment Control
• /
• v.16 no.3
• /
• pp.247-251
• /
• 2007

To extend the shelf-life of spinach after harvest, we investigated the effect of various packaging methods and storage temperature. In case of polypropylene film package, there was no weight loss, but in non-package, remarkably weight loss occurred as storage period extended and storage temperature risen. Content of vitamin C was decreased rapidly at early stage of storage, and decrease of vitamin C in low temperature storage was lower than that of room temperature storage, but its large difference according to packaging method was not observed. In hunter's value on spinach, b value in room temperature storage was higher than that of low temperature storage. In terms of freshness, shelf-life of spinach by low temperature storage $(1{\sim}3^{\circ}C)$ after PP film packaging lasted 34 days, and that by room temperature storage $(10{\sim}15^{\circ}C)$ after PP film packaging lasted 8 days, but that by room temperature storage after non-packaging lasted 3 days.

• Korean Journal of Food Science and Technology
• /
• v.36 no.2
• /
• pp.365-367
• /
• 2004

Electrolyzed-acid water was used to prolong shelf life of salted Chinese cabbage during storage, Chinese cabbage was salted, washed twice with electrolyzed-acid water, packaged in high-density polyethylene film, and stored at $10^{\circ}C$. Titratable acidity, pH, color, and microbial loads of salted Chinese cabbage were measured. Treated sample showed lower pH, total microbial count, and lactic acid bacteria than those of control, whereas almost equal titratable acidity and color, Acidity of treated sample maintained lower pH value until 6 days, and remained constant thereafter, Sharp decrease in L value occured after 2 days for control, and was delayed 4-6 days for treated sample. Salted Chinese cabbage treated with electrolyzed-acid water showed lower total microbial load ($10^3\;CFU/mL$) and lactic acid bacteria ($10^1\;CFU/mL$) after washing, whereas similar loads, compared to control after 6 days. Treatment with electrolyzed-acid water maintained higher quality for salted Chinese cabbage, with limited shelf life extension.

• Korean Journal of Food Science and Technology
• /
• v.34 no.4
• /
• pp.746-749
• /
• 2002

From 7 different medicinal herbs, Rubus coreanus miquel, Therminalia chebula Retz and Rhus javanica was selected by paper disk method against 10 different microorganisms. The ethanol extracts of selected herbs was added into Tofu, and the total viable cell counts was determined. After 4 days, total viable cell count reached to $10^7$ and the Tofu putrefacted. The tested sample added with 0.01% of Terminalia Chebula Retz extract, the shelf-life was extended as 108.8%, with 0.05% was 117.3% and with 0.1% was 132.6%. Among 3 kinds of medicinal herb, Therminalia chebula Retz has better powerful activity than others.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.56 no.4
• /
• pp.512-519
• /
• 2023

Pacific oysters Crassostrea gigas are a popular shellfish in the Republic of Korea. However, due to their abundant moisture and nutrient content, oysters are susceptible to microbiological growth and biochemical changes, which lead to quality degradation. Therefore, the present study aimed to investigate the effectiveness of modified atmosphere packaging (MAP) in maintaining the quality of raw oysters during storage. Microbiological and physicochemical parameters such as pH, glycogen content, soluble protein, turbidity, and volatile basic nitrogen (VBN) were analyzed for oysters stored under various gas compositions and storage periods. The results showed that there was no significant increase in viable cell count in MAP oysters after six days in MAP oysters. Moreover, the physicochemical quality of non-MAP oysters deteriorated rapidly, whereas the quality of MAP oysters were maintained during storage. This study suggests that MAP can be an effective technique for maintaining the freshness of raw oysters during distribution and storage, and may also be useful for extending the shelf-life and maintaining the quality of other seafood products.

• Food Science of Animal Resources
• /
• v.30 no.4
• /
• pp.674-684
• /
• 2010

The effects of ascorbic acid (AA) alone or in combination with sodium acetate/calcium lactate (AA+SACL) and chitosan (AA+CH) on the physicochemical properties and microbial growth of beef and pork patties stored at $5^{\circ}C$ were investigated. The patties were case-ready packed in an air-containing polypropylene (PP) tray and sealed with polyethylene terephthlate (PETP)/casted polypropylene (CPP) top film. Treatments with AA, AA+SACL and AA+CH were effective in inhibiting total aerobic bacteria from day 4 compared to the control. In general, thiobarbituric acid, volatile basic nitrogen, and hue values in treated samples were lower than the control over the storage, whereas Hunter ${\alpha}^*$ (redness) values and sensory scores for surface color and off-odor were higher. Regarding quality and shelf-life extension, ground beef and pork patties treated with AA+SACL produced the most desirable results among all treatments during storage.

• Korean Journal of Food Science and Technology
• /
• v.22 no.5
• /
• pp.514-519
• /
• 1990

Some chemical constituents were monitored to evaluate the biochemical and nutritional aspects of ${\gamma}-irradiated$ mushrooms associated with shelf-life extension. Volatile components identified by GC and GC-MS were composed primarily of 1-octen-3-ol(68%)). benzaldehyde(13%), 3-octanone(8%), benzyl alcohol(5%), 3-octanol(2%)). 1-octen-3one(1%). etc. Treatment with 2kGy-irradiation and subsequent storage for 17 days at $(9{\pm}1^{\circ}C\;and\;80{\pm}7%$ RH resulted in appreciable changes In their contents. even though negligible changes were observed in GC patterns between the nonirradiated and 2 kGy-irradiated samples. Most of the amino acids were resistant to ionizing energy of 2 kGy, while sulfur-containing free amino acids were affected significantly by ${\gamma}-irradiation$.

• Food Science and Preservation
• /
• v.12 no.6
• /
• pp.534-539
• /
• 2005

Effects of grapefruit seed extract and Ag ion solution on the keeping quality and shelf life of mungbean sprouts were investigated in terms of weight loss, gas composition, hardness, color, ascorbic acid content, and viable cell counts during storage. Packages with $30\;{\mu}m$ polypropylene(PP) film was applied for mungbean sprouts dipped in Ag ion solution, 50 ppm and 100 ppm GFSE, 50 ppm and 100 ppm GFSE in Ag ion solution and stored $5^{\circ}C$. Totally weight loss exceeded $1\%$ and no visible signs of shrivelling of mungbean sprouts were observed. GFSE in Ag ion solution treatment, resulting in mungbean sprouts of better visual quality, weight loss, color, ascorbic acid as compared to the control without dipping. A shelf life of 6 days was achieved with 100 ppm GFSE in Ag ion solution treatment.

• Journal of Bio-Environment Control
• /
• v.17 no.2
• /
• pp.96-100
• /
• 2008

To extend the shelf-life of kidney bean (Phaseolus vulgaris L.) after harvest, we investigated the effect of packaging material and storage temperature. In case of film package, there was no weight loss during storage, but in paper-box package, remarkable weight loss occurred as storage period extended and storage temperature risen. Firmness of kidney bean was greater in low temperature than ambient temperature storage. Content of vitamin C was decreased rapidly during storage, and in paper package, low temperature storage group had lower decrease of vitamin C than that of room temperature. Total chlorophyll content was not difference among storage temperatures in film package treatments. However, in paper-box package, decrease of chlorophyll in room temperature storage was greater than that of low temperature ($8{\sim}10^{\circ}C$). In terms of freshness of kidney bean, we suggest that shelf-life by low temperature storage ($8{\sim}10^{\circ}C$) after PP film or paper package was 8 days, but that by room temperature storage after paper package was 4 days.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.39 no.3
• /
• pp.455-460
• /
• 2010

This study was investigated the effect of the ultra filtration (UF) on extending shelf-life and increasing quality of Acer mono sap. To evaluate the quality changes of Acer mono sap before and after UF, crude ash, crude protein, minerals, free sugar, organic acid, pH, total acidity, browning index, turbidity and total microbial number were measured during storage periods at -1, 4 and $10^{\circ}C$. After UF, the ash, minerals, organic acid, total acidity, browning index and turbidity of Acer mono sap were slightly decreased, while the pH was slightly increased, and total microbial number was not detected. After UF, the pH, total acidity, browning index, turbidity and total microbial number of Acer mono sap were very stable during storage periods at -1 and $4^{\circ}C$. During the storage at $10^{\circ}C$, turbidity and total microbial number was slightly increased, while the pH of before UF was decreased and the total acidity, browning, turbidity and total microbial number was increased during storage periods. As the results of this study indicate application of UF on Acer mono sap could extend the shelf-life and quality without loss of natural minerals and useful components.