• Food Science and Preservation
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• v.4 no.2
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• pp.189-196
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• 1997

Blanching conditions for immatured soybeans were optimized by analyzing the effects of various time/temperature blanch treatment on the activities of peroxidase and lipoxygenase, the stability of vitamin C and color, and moisture content in immatured soybeans for the purpose of minimizing quality deterioration during frozen storage. Blanching at 96$^{\circ}C$ for 70 sec led to maximum inactivation of lipoxygenase in the immatured soybeans, while my blanching conditions tested in this study were not enough to inactivate peroxidase. Blanching at 82$^{\circ}C$ for 60 sec resulted in the highest amount of vitamin C remaining in the immatured soybeans after blanching. Hunter -a/b ratios of immatured soybeans blanched at 82$^{\circ}C$ for 60 sec and hue values (ΔE) of the immatured soybeans blanched at 76$^{\circ}C$ for 60 sec showed the closest values to those of fresh products. The changes in moisture content of immatures soybeans was not so significant after blanching. In conclusion, it was suggested that immatured soybeans be blanched at 96$^{\circ}C$ for 70 sec to minimize lipoxygenase activity and resulting quality deterioration, while blanching at 82$^{\circ}C$ for 60 sec was recommended to stabilize vitamin C and color.

• Food Science and Preservation
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• v.14 no.6
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• pp.584-590
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• 2007

This study investigated quality characteristics of Aster scaber (color; firmness; vitamin C, chlorophyll and phenolic contents; and sensory properties) under blanching conditions of $90^{\circ}C$/25 min, $95^{\circ}C$/16 min, and $100^{\circ}C$/6 min, and salt concentrations of 0%, 1% and 2%. The contents of vitamin C, chlorophyll and total phenolic compounds, and firmness decreased by 39.5-60.3%, 26.2-31.5%, 45.6-50.1% and 50.7-51.1%, respectively, after blanching. For these parameters, treatment with 1% salt was 7.1-30.2%, 9.2-12.2%, 35.9-52.0% and 2.7-6.8% relative to the control, and drip water could be prevented by 3.3-23.4%. Results for treatment with 2% salt were (respectively) 22.7-34.1%, 10.4-20.7%, 55.5-80.4% and 13.8-17.3%, and drip water could be prevented by 23.9-27.3%. These results showed that 2% salt treatment had a greater effect on preservation of quality characteristics than 1% treatment and the control. With respect to sensory evaluation, the 2% treatment had lower overall acceptability than the 1% treatment because of the saltier taste. However, the 1% treatment was more acceptable than the control. The optimal blanching condition was found to be $100^{\circ}C$/6 min and 1% salt.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.2
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• pp.246-253
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• 2012

In this study, we determined the optimum blanching conditions for pretreatment of Aster scaber prior to freezing to ensure its long, safe preservation as a fine cooking ingredient. Frozen-thawed A. scaber did not significantly differ between blanching groups, but the blanched group showed significantly higher Hunter L, a, and b values than the un-blanched group (p<0.05). Higher temperatures and longer treatment times increased softness; hardness did not significantly differ between the blanched and un-blanched groups of frozen-thawed A. scaber (p<0.05). Total bacterial counts and the presence of coliforms seemed to decline with blanching treatments, but treatment temperature and time did not influence this reduction. Over 95% of peroxidase activity was inactivated by blanching treatment but increased slightly after thawing. The sensory evaluation of the frozen-thawed A. scaber by test group showed the A. scaber blanched at $90^{\circ}C$ for 3 min to be the most highly preferred (p<0.05).

• Korean Journal of Food Science and Technology
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• v.43 no.4
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• pp.426-431
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• 2011

In this study, we set an optimum blanching condition as a pretreatment condition to freeze welsh onion (Allium fistulosum L.) for the purpose of preserving the cooking material for long-term usage. With higher blanching temperature and longer processing time, the Hunter color values and the hardness of welsh onion tended to decrease, which confirmed softening of the tissue. Compared to before blanching, total bacterial counts decreased to near 2 log scale, whereas coliforms were not detected or decreased to a 1-2 log scale. Blanching by heating at 100$^{\circ}C$ for 5 min decreased peroxidase inactivity to more than 94%, whereas only 47% of the inactivity was achieved at 80$^{\circ}C$ for 1 min. The sensory evaluation for the blanched and defrosted welsh onion showed that the group blanched at 80$^{\circ}C$ for 1 min was preferred significantly (p<0.05).

• Food Science and Biotechnology
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• v.17 no.3
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• pp.534-539
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• 2008

This study investigated the effects of pretreatment and storage conditions on the properties of stored chestnuts. Effects on chestnuts of refrigerated storage (RNT) and frozen storage (FNT) with no pretreatment, frozen storage after oxalic acid treatment without blanching (FON) and with blanching (FOB) were examined. Water binding capacity, swelling power, solubility, and viscosity of the starch produced from RNT, FNT, and FON were similar to those of the starch produced from control (CON). FOB showed significant differences in these properties from CON. Textural properties of starch gels prepared from stored chestnuts except FOB also were very similar to those of CON starch gels. The sensory characteristics of steamed FON and FNT were similar to those of steamed CON except in brown color and hardness. Steamed FNT tended to have higher brown color and lower hardness than steamed FON. Steamed RNT showed significant differences in all the sensory properties except in hardness and cooked chestnut flavor. Steamed FOB was significantly higher than steamed CON in water release and off-flavor. Among the storage conditions examined, frozen storage with oxalic acid treatment is recommended for the long-term storage of chestnuts.

• Journal of the Korean Society of Food Culture
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• v.36 no.5
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• pp.512-521
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• 2021

This study investigated the quality characteristics of sweet pumpkin after blanching. Sweet pumpkins were blanched in distilled water, 2% citric acid and 2% NaCl water at 100℃ for 3 min. The cooking loss of sweet pumpkin in the blanching groups was lower than that in the control group, and greenness and yellowness in the blanching groups were higher than those in the control group (p<0.001). Total polyphenol content (TPC) of sweet pumpkin increased after blanching (p<0.05), and TPC true retention (TR) was measured with the highest NB. CON and NB were significantly higher in ?-carotene content (p<0.001). Lutein content in the blanching treatment groups was lower than that in the control group, but NB was the highest between the blanching groups (p<0.001). DPPH and ABTS⁺ radical scavenging activity assays revealed higher antioxidant activity in the NB groups among the blanching groups (p<0.001). The CON was 2.44 log colony-forming unit (CFU)/ g in the total bacterial count, but there were no microorganisms in the blanching groups. In conclusion, blanching with the addition of 2% NaCl can inhibit the growth of microorganisms and improve TR and antioxidant activities in sweet pumpkin.

• Food Science and Preservation
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• v.20 no.5
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• pp.628-635
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• 2013

This study was conducted to investigate the changes in the physicochemical properties of Peucedanum japonicum Thunb. after blanching. After blanching treatment, the crude protein content decreased but did not affect the crude fat, crude ash and carbohydrate contents of P. japonicum. All the detected free sugar contents decreased after blanching, but the total free sugar content decreased by 14.8% from that of the raw P. japonicum after blanching. The total amino acid and essential amino acid contents of the blanched P. japonicum. decreased by 10.75% and 15.22% from those of the raw P. japonicum. There were no differences in the contents of the total fatty acid between the raw and blanched P. japonicum. The total organic acid content decreased by 37.03% from that of the raw P. japonicum. after the blanching, and the reduction of the acetic acid was largest in the organic acid. The vitamin A, C and E contents decreased by 20.20%, 8.23% and 35.59% after the blanching. The total mineral content of the blanched P. japonicum. decreased by 21.84% after the blanching. The nutrients in the P. japonicum were essential amino acid, vitamin C, minerals, but these were reduced after the blanching. Therefore, the blanching conditions that can reduce nutrient loss of P. japonicum must be established.

• Food Science and Preservation
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• v.19 no.6
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• pp.866-872
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• 2012

This study was conducted to investigate the changes in physicochemical properties of Spergularia marina Griseb by blanching. The proximate composition, free sugar, free amiao acid, organic acid, vitamin and mineral composition of raw and blanching Spergularia marina Griseb were compared. After blanching treatment, the moisture and carbohydrate contents of Spergularia marina Griseb increased, but the crude protein, crude fat and crude ash contents decreased. Total free sugar content decreased by 62.50% compared with raw Spergularia marina Griseb after blanching, and the reduction of galactose was the largest in free sugars. The raw and blanched Spergularia marina Griseb contained all the essential amino acids, except tryptophan. The total amino acid and essential amino acid contents were reduced by blanching, but the essential amino acid ratios of the raw and blanched Spergularia marina Griseb were similar. The amounts of all the detected organic acids were reduced by blanching, except acetic acid. Spergularia marina Griseb was found to contain high levels of vitamin C, vitamin E, and minerals, but these were reduced by blanching. These results showed that most of the nutrients contained by Spergularia marina Griseb are decrease by blanching. Therefore, the blanching conditions that can reduce nutrient loss of Spergularia marina Griseb must be established.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.5
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• pp.647-654
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• 2012

This study was conducted to investigate the physicochemical properties of raw and blanched $Haetsun$ vegetables. The proximate composition, reducing sugar, free amino acid, organic acid, vitamin C and mineral composition were compared between raw and blanched $Haetsun$ vegetables. After blanching treatment, the moisture content of $Haetsun$ vegetables was increased, but the crude ash, crude fat, crude fiber, and crude protein content decreased in all samples. $C.$ $sinensis$ contained the highest level of reducing sugar with 1,518.16 mg% among all samples, and the content of the reducing sugar was decreased after blanching in all samples. Raw and blanched $Haetsun$ vegetables contained all essential amino acids except tryptophan. The vitamin C content of blanched samples was reduced 29~88% compared with raw samples. All $Haetsun$ vegetables contained high levels of potassium and calcium regardless of blanching. From these results, even though this study confirmed that $Haetsun$ vegetables were rich in vitamin C and minerals, their high amount of nutrient was reduced by blanching. Therefore, blanching conditions which can keep food value of $Haetsun$ vegetables must be established, because most of the nutrient composition of $Haetsun$ vegetables decreases by blanching.

• Food Science and Preservation
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• v.23 no.7
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• pp.939-944
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• 2016

The aim of this study was to establish an optimum blanching condition for outer cabbage leaves to increase utilization of the byproduct. Outer leaves of Kimchi cabbages were cut to size ($4{\times}4cm$) and blanched at 80, 90, $100^{\circ}C$ for 1, 3, and 5 min. Subsequently, weight loss, pH, total bacteria, coliform and texture properties were investigated. Sensory evaluation of a ready-to-cook soup prepared from blanched outer leaves was investigated to determine whether the quality of the blanched outer leaves was acceptable. Both weight loss and pH of outer leaves of Kimchi cabbage were increased by blanching. Compared to raw samples, total bacterial counts decreased and coliform bacteria were not detected. The hardness of raw leaf samples was $1.5kg{\cdot}force$ (N). Sample hardness was 18.7~21.7% lower after blanching for 3 min and 34.8~36.7% after blanching for 5 min. Sensory evaluation of outer leaves blanched at $100^{\circ}C$ for 5 min revealed significant differences from the other treatments (p<0.05). In addition, sensory evaluation scores for texture and appearance of outer leaves blanched at $100^{\circ}C$ for 3 min were higher than those for commercially available products. The results of this study indicate that blanching can be effective for developing a food product from the outer leaves of Kimchi cabbage.