• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1086-1092
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• 2003

This study was carried out to investigate the effectiveness of blanching on the different drying methods and to examine the quality properties of carrots dried by freeze., vacuum- or hot air-drying during storage. Blanched carrots (BC) dried faster than raw carrots (RC), while RC showed more effective rehydration than BC by hot air- and vacuum-drying methods. There was more stability for BC on carotene retention and browning degree than RC in all drying methods during storage. Moreover, firmness of RC and BC by vacuum-drying was slightly lower than that of hot air-drying, but higher than freeze-drying. In firmness, BC and RC showed similar trends with different drying methods (decreasing with increased storage periods), while BC showed about 3 time firmer texture than RC in all cases during storage. The dried carrots prepared with blanching treatment showed more fine structures than those not treated. These results showed that the blanching treatment of carrots was good for maintaining quality by various drying methods.

• Journal of Food Hygiene and Safety
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• v.38 no.3
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• pp.164-169
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• 2023

Vegetables are rich sources of dietary fiber, which exhibit various health benefits. In the Republic of Korea, vegetables are consumed after cooking using different methods. However, they are most commonly eaten raw or blanched. In this study, chamnamul, sesame leaf, Fischer's ragwort, burdock root, and garlic stem from Korea were analyzed according to the Korean Food Code, and changes in dietary fiber content after blanching were compared. Blanching reduced the total dietary fiber (TDF) content in chamnamul (from 3.67±0.03 to 2.61±0.14 g/100 g), burdock root (from 4.95±0.40 to 3.89±0.10 g/100 g), and sesame leaf (from 4.32±0.12 to 3.65±0.17 g/100 g), but increased it in Fischer's ragwort (from 6.09±0.49 to 6.43±0.01 g/100 g) and garlic stem (from 4.52±0.35 to 5.09±0.04 g/100 g). Sucrose, glucose, and fructose were detected in the vegetables; however, sesame leaf did not have sucrose. Fresh burdock root had the highest sucrose content (1.71±0.07 g/100 g) whereas garlic stem had the highest glucose and fructose content (1.65±0.02 and 1.73±0.02 g/100 g, respectively) compared with other vegetables. Upon blanching, the free sugar content of vegetables decreased for all sugars except for sucrose, which increased in Fischer's ragwort (from 0.10±0.01 to 0.14±0.01 g/100 g) and garlic stem (from 0.76±0.00 to 0.83±0.01 g/100 g). These results can provide information on blanching-associated changes in the content of dietary fiber and free sugar in foods prepared using these vegetables.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 1998.09a
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• pp.66.1-66
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• 1998

• Korean Journal of Food Science and Technology
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• v.7 no.2
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• pp.100-106
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• 1975

• Korean journal of food and cookery science
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• v.10 no.4
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• pp.369-375
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• 1994

This study was carried out to investigate the effect of beany flavor elimination and the acceptability of tofu prepared with blanched soybean. The results were as follows: 1. The content and me total protein of soymilk prepared with blanched soybean were decreased comparing with those of soymilk prepared with raw soybean. But the yield of tofu was not changed by blanching the soybean. 2. The beany flavor(hexanal, 1-hexanol, and pentanoI) was decreased but the toasted nutty flavor(ethanol and propanol) were increased by blanching the soybean. 3. By heating of soymilk, most of volatile compounds was disappeared, but ethanol, hexanal and 1-hexanol were remained. The hexanal content of tofu prepared with raw soybean was eleven times higher than that of tofu prepared with blanched soybean. 4. The color of tofu prepared with blanched soybean was more yellower than that of control group. At the lower temperature of blending, the texture of tofu was more smooth and elastic. 5. The tofu prepared with blanched soybean was more tasteful.

• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 2001.12a
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• pp.131-131
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• 2001

The enzyme activity and organoleptic properties of Korean pickled cucumber were studies for their changes during fermentation. The Korean pickled cucumber were prepared by blanching and high temperature soaking in salt solution and trehalose treatment The results shelved that the effect of combined heat and trehalose treatment significantly reduced the fermentation rate and softening rate of texture while a rather rapid fermentation was for those pleserved with salt. The effect of trehalose treatment enhenced fermentation and it was significantly reduced softening rate of texture by 2% treatment. The sensory evaluation of Korean pickled cucumber was found that combined heat treatment with blanching and hot solution had a positive effect for reduction of softening of cucumber tissue, however, odor and taste were not significantly affected. This study suggested that combined heat and trehalose treatment might have potential for affording protection against softness of cucumber tissue during the fermentation time.

• Food Science and Preservation
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• v.5 no.3
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• pp.305-314
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• 1998

In the drying process, many undesirable physicochemical changes occur that influence dried food product qualities. Pretreatments method is used to reduce the deterioration of dried food product qualities such as color, flavor, texture, rehydration ability and retention of nutrients. The methods of pretreatments are blanching, chemical treatment and osmotic dehydration. Osmotic dehydration is a water removal process which is based on placing foods in a concentrated osmotic solution or in a dry osmotic material. A large number of process variables have a significant effect on process and final product quality. In order to improve final product quality it is necessary to know the role of each process variable and understand the mecanisms throughout the process. Osmotic dehydration is a valuable processing tool with great future in minimal processing of fruits and vegetables.

• Journal of the East Asian Society of Dietary Life
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• v.10 no.1
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• pp.42-47
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• 2000

Flavonoids in commerical green-yellow vegetables (carrot, mugwort, perilla leaf, leek and water dropwort) were analyzed by HPLC. Flavonoids analyzed in samples were myricetin, luteolin , qercetin, apigenin and kaempferol. When 2N HCI and a reaction period of 1 hours was used, quercetin and kaempferol could be detected in leek and water dropwort, luteolin and apigenin could be detected in perilla leaf. Increasing reaction period up to 6 hours with 2N HCI led a degradation of quercetin and kaempferol to approximately 90% in leek and water dropwort, but it led to a increasing of luteolin and apigenin of maximum 300% in perilla leaf. After the blanching process, the amount of the flavonoids increased whereas the components of the flavonoids were not changed.

• Proceedings of the PSK Conference
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• 2000.04a
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• pp.179.2-179.2
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• 2000

• Food Science of Animal Resources
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• v.35 no.4
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• pp.441-448
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• 2015

Blanching beef for use in home meal replacements (HMR) is an important process that determines the final quality of the beef after the cooking process. Thermal pretreatment also minimizes the change in quality during the main cooking process or storage. In this study, beef samples were washed and sliced, then treated by immersion in boiling water (1-10 min), steaming (1-10 min), or pan-frying in oil (30-240 s). The color after each thermal treatment showed higher L* and b* values and lower a* values compared with the raw beef, except for the pan-frying thermal treatment. The total color difference (∆E) and pH value were significantly increased by panfrying (p<0.05). There was no significant difference in the shear force of the beef samples, except for the sample pan-fried for 210 s. The nutritional content of beef was measured as the moisture, protein, fat, and ash contents, which were 69.96, 16.64, 3.49, and 1.13%, respectively, in raw beef. After thermal treatment, the crude protein and fat contents were increased, whereas the moisture and ash contents decreased. The mineral content, including Na, Mg, Fe, and Ca was highest after pan-frying. The heat treatment decreased microorganisms in all the samples. The total bacteria count in raw beef was 4.5-4.7 Log CFU/g, whereas the bacteria count decreased to 2.2-2.8 Log CFU/g after blanching. Thermophilic bacteria, coliform, mold, and yeast not detected in any thermally treated sample.