• Asian-Australasian Journal of Animal Sciences
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• v.14 no.2
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• pp.268-275
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• 2001

The effects of homogenization conditions and $\beta$-cyclodextrin ($\beta$-CD) on cholesterol removal of Mozzarella cheese were examined. The homogenization pressure influenced markedly on the cholesterol removal in milk and, 75.64% of cholesterol, the highest rate, was removed at $70.0kg/cm^2$. In addition, an increase in temperature resulted in an increase of cholesterol removal in the range of 71.75 to 78.22%. Among different concentrations of $\beta$-CD addition, 1.0% showed 78.21% of cholesterol removal. Therefore, cholesterol-reduced Mozzarella cheese was made by cheese milk treated with 70 $70.0kg/cm^2$ homogenization at $70^{\circ}C$ and 1% $\beta$-CD addition for a subsequent study. The cholesterol reduction of cholesterol-reduced Mozzarella cheese was 63.92%. Meltability, stretchability and oiling-off in cholesterol-reduced cheese were significantly lower than those in control. Hardness, gumminess and chewiness were significantly reduced, while cohesiveness and elasticity increased. Appearance and flavor of the cheese were superior, but texture inferior to the control.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.6
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• pp.754-760
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• 2006

This study was conducted to examine the quality characteristics of canned kimchi prepared by minimal thermal processing. Korean cabbage kimchi was fermented at $20^{\circ}C$ for several days up to acidity $0.5{\pm}0.1%$, was packaged in cylindrical can of 115 mL and pasteurized at low temperature. Thermal processing times based on $F_{60}$ value at geometrical center of the can were determined as 23.1, 17.7 and 12.7 min at 65, 70 and $80^{\circ}C$, respectively. The quality changes of the processed kimchi were measured during storage at $20^{\circ}C$. The pH of pasteurized kimchi was higher than that of unpasteurized control. The number of lactic acid bacteria was reduced to about $10^{2}{\sim}10^{3}$ (CFU/mL). The pasteurized kimchi product showed better texture and color values compared to the control, while resulting in the lower carotenoid and ascorbic acid contents. Kimchi preparation by minimal thermal processing had a positive effect for reduction of sour taste and sour flavor in sensory quality, but gave adverse effect in acceptability because of off-taste and off-flavor.

• Food Science and Preservation
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• v.23 no.3
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• pp.369-377
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• 2016

This study was conducted to investigate the effects of superheated steam (SHS) on volatile compounds and the quality characteristics of onion. Onion samples were treated by SHS at various steam temperatures ($100{\sim}300^{\circ}C$) for 1 min. Thiosulfinates and pyruvic acid were reduced by SHS treatment. The absorbance values obtained for thiosulfinates, the odor-causing compounds in onions, treated by were 0.889, 0.085, 0.049, 0.049, and 0.045, while that of the untreated control sample was 1.587. The pyruvic acid contents of onions treated by SHS were 7.57, 5.85, 1.66, 0.47, and 0.26 mg/mL, while that of the untreated control sample was 8.00 mg/mL. Volatile compounds such as, dipropyl trisufide, 1,3-propanedithiol, methyl thiirane, methyl propyl trisulfide, diallyl disulfide, 1-(methylthio)-1-propene, 1,1-thiobis-1-propene, 1,1-sulfinyl bispropane, dimethyl tetrasulfide, methyl propenyl disulfide, dimethyl trisulfide, and diallyl disulfide were reduced by SHS treatment. The results showed that antioxidant activities in the of onion samples were improved by SHS treatment. The hardness and chewiness of onions treated by SHS were significantly lower than those of the untreated control onion sample. Sensory evaluation suggested that SHS could help lower off-flavors in and enhance the palatability of onions. These results suggest that the application of SHS treatment to onions can decrease their off-flavors, change their textural attributes, and promote their sensory properties.

• Food Science and Biotechnology
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• v.18 no.5
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• pp.1132-1137
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• 2009

Successive application of Saccharomyces cerevisiae DSM 70424 and Saccharomyces rouxii DSM 2535 or DSM 2531 in the production of non-alcoholic beer was investigated. The aim of the study was to consider the impact of the 2 mentioned strains of S. rouxii on the reduction of alcohol content in wort fermented at 12 or $24^{\circ}C$ for 96 hr, applying periodic aeration. The 2 S. rouxii strains were added at the $48^{th}$ hr of fermentation after thermal inactivation of S. cerevisiae cells. The greatest alcohol decrease rate was observed for the treatment containing S. rouxii DSM 2535-fermented at $24^{\circ}C$ (from 1.56 to 0.36%). The concentration of acetaldehyde, diacetyl, and 2,3-pentandione, that have a key role in appearance of 'wort' and 'buttery' off flavors, were significantly lower in S. rouxii-containing treatments fermented at $24^{\circ}C$. S. rouxii-containing treatment fermented at $24^{\circ}C$ showed slightly lower overall flavor acceptability compared to S. cerevisiae-containing treatment fermented at the same temperature. Such score was improved for the products obtained at $12^{\circ}C$.

• Food Science of Animal Resources
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• v.37 no.6
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• pp.804-812
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• 2017

This study was carried out to determine the physicochemical, microbiological, and quality characteristics of a new type of fermented sausage manufactured by incorporating Baechu-kimchi powder and gamma-aminobutyric acid (GABA)-producing lactic acid bacteria (LAB). The LAB count was at the maximum level by day nine of ripening in inoculated sausages, accompanied by a rapid decrease in the pH. The addition of kimchi powder decreased the lightness ($L^*$) and increased the redness ($a^*$) and, yellowness ($b^*$) values, while also significantly increasing the hardness and chewiness of the sausage (p<0.05). Moreover, although the thiobarbituric acid reactive substances values increased in all samples during the study period, this increase was lower in the kimchi-treated samples, indicating a reduction in lipid oxidation. Overall, our results show that the addition of Baechu-kimchi powder to sausages reduced the off-flavor properties and improved the taste profile of the fermented sausage in sensory evaluations. The GABA content of all fermented sausages increased from 17.42-25.14 mg/kg on the third day of fermentation to 60.95-61.47 mg/kg on the thirtieth day. These results demonstrate that Baechu-kimchi powder and GABA-producing LAB could be functional materials in fermented sausage to improve quality characteristics.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.12
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• pp.1769-1775
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• 2016

Aerial parts (leaves and stems) of radish are usually discarded due to the distinct undesirable flavors associated with inappropriate preparations, despite their many health benefits. In this study, we examined the role of extrusion process in the removal of off-flavors and elevation of antioxidant activity in radish (Raphanus sativus L.) leaves and stems. To optimize the extrusion conditions, we changed the barrel temperature (110, 120, and $130^{\circ}C$), screw speed (150, 200, 250, and 300 rpm), and moisture content (20, 25, and 30%). The polyphenol and flavonoid contents significantly increased in extruded radish leaves and stems (ER) under optimum extrusion conditions ($130^{\circ}C$, 250 rpm, and 20%). Under extrusion conditions, we compared off-flavors (as amount of sulfur-containing compound) levels between ER and non-extruded radish leaves and stems (NER) by an electronic nose. A total of six peaks (sulfur-containing compound) were similarly detected in both ER and NER, whereas the ER showed reduced off-flavors. Levels of glucosinolate (${\mu}g/g$), which can be hydrolyzed into off-flavors during mastication or processing, were significantly decreased in the ER. From these results, extrusion processing can be an effective method to increase anti-oxidant activity and removal of off-flavors in radish leaves and stems.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.4
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• pp.271-282
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• 1982

The browning development, mainly through the Maillard reaction, occurring in the dried fish meat products during storage causes reduction of the nutritional value due to the loss of the essential amino acid such as available lysine as well as off -flavor resulting in the deterioration of the food quality thus shortening the shelflife. In the work, the changes in the amount of available lysine, extractable nitrogenous compounds (nonprotein-N, amino-N, trimethylamine oxide, trimethylamine, and free lysine) and development of browning were measured to assess the relationship between the shelflife and the quality loss in dried filefish under the steady state conditions (35,45, and $55^{\circ}C;a_{w}'s$ of 0.44 0.52, 0.65 and 0.75 at each temperature) and fluctuating temperature condition of $35/55^{\circ}C$ will. alternating 7 day periods at each water activity. The results indicated that the amount of available lysine and extractable nitrogenous compounds except TMA decreased rapidly with increasing temperatures and water activities while the rate of available lysine and extractable nitrogenous compounds must be involved in the initial stage of brown pigment formation. The available lysine loss of the dried filefish products stored under the fluctuating temperature conditions was greater than that stored under its fixed mean temperature, $45^{\circ}C$. The activation energies for lysine loss obtained from the Arrhenius plot ranged 6.9 to 4.4 Kcal/mol and $Q_{10}$ values at $40^{\circ}C$ were 1.4 to 1.2. The values for browning were 15.7 to 14.4 Kcal/mol and 2.2 to 2.0 respectively. Shelf-life, defined as the time to reach 0.15 O. D./g solid or the limit of off-color deterioration by browning reaction, was extented longer than the halflife of Iysine loss, actually corresponding $75\%$ loss of available lysine. This suggested that the halflife of lysine loss might not be adequate to assess the shelf-life of the food system with high potential of protein, nonproteinous nitrogen compounds, and lipids.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.1
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• pp.104-108
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• 2006

Effect of gamma irradiation on the softening of dried fernbrake at different moist-heating conditions was investigated. Dried fernbrake packaged in controlled atmosphere $(CO_2\;25\%,\;N_2\;75\%)$ was irradiated up to 7 kGy with $\gamma-ray$. Hardness of dried fernbrake was significantly decreased at the irradiation dose of above 5 kGy. Hardness of cooked fernbrake was significantly decreased with increasing irradiation dose level as well as heating temperature and time. $DT_{50}$ value (The heating time required to reach the $50\%$ reduction of hardness) for irradiated fernbrake was shortened according to dose level as well as heating temperature and heating time: $DT_{50}$ value of control: 23 min, 5 or 7 kGy: $2.2\~5.0$ min at $60^{\circ}C$. Also, the activation energy for softening of irradiated fernbrake ($1.85\~1.88$ kcal/mole for $5\~7kGy$) decreased compared to control (4.30 kcal/mole). Moisture content, swelling and rehydration rate of gamma irradiated fernbrake during moist heating increased according to the irradiation doses. Sensory results showed that scores of off-flavor and odor in irradiated fernbrake upto 7 kGy were not significantly different from control. Based on these results, gamma irradiation was effective for the reduction of cooking time and the activation energy for softening of dried fernbrake with increasing dose levels.

• Journal of Food Hygiene and Safety
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• v.23 no.4
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• pp.330-337
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• 2008

Betarich carrots were washed at various hypochloric acid(HCA) concentration and steeping time and packed in PE bag keeping at $8^{\circ}C$ for 12 days, in order eventually to examine microbiology, firmness, surface color, whiteness index(WI) and sensory quality. It was found that total bacterial counts at T-II and T-III with the 3 minute steeping were $4.37{\pm}0.19\;\log\;CFU/g$ and $4.27{\pm}0.13\;\log\;CFU/g$ respectively, showing slight decrease compared to control condition. E. coli was not detected at all treatments but less coliforms were detected at the 8-day treatments of T-II and T-III. Treatment of 3-minute steeping showed smaller reduction in firmness than that of I-minute steeping at 12-days, and T-1 (T-3) had the largest (smallest) reduction among them. It was also found that during the treatment the L-value showed decreasing trend, but the parameter a- and b-value showed increasing trend. WI increased, and its change was small with the increase in HCA concentration. The sensory quality check after 8 day storage showed that evaluation of the off-flavor appeared to be significantly high (p<0.05) at both non-treatment and HCA treatment. On the basis of the results above, it is likely to be more effective to prolong the period of circulation of beta rich carrots if you use HCA over 50 ppm for washing betarich carrots. This study will contribute to improve safety and quality in circulation of beta rich carrots.