• Korean journal of food and cookery science
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• v.11 no.2
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• pp.98-103
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• 1995

The effect of blanching time, blanching water and power settings of microwave oven on the minerals retention in spinach and broccoli were investigated. The vegetables were blanched for 60, 120 and 180 sec, with water 0ml, 50ml and 100ml every 100 g of raw material at two different power settings (700w, 400w). The retention of minerals(Ca,K,Mg,Cu,Fe,Na,p) in spinach and broccoli were higher at the 400w power than 700w power level, regardless of blanching time. At the high power, the retention of minerals in spinach and broccoli were reduced remarkably as the blanching time increased. The reason for this is that the increasing power level results in greater water coming ou from the vegetable. Also, minerals in vegetable as coming out with this water loss in proportion to the blanching time.

• Korean Journal of Food Science and Technology
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• v.31 no.5
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• pp.1216-1220
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• 1999

The effects of low-temperature blanching on the physical properties of chestnut powder were studied. Chestnuts were blanched in water for 15, 30 and 60 min., each at three temperatures viz. $45^{\circ}C,\;55^{\circ}C$ and $65^{\circ}C$. The particle size of chestnut powder was prepared smaller than 60 mesh$(250\;{\mu}m)$. Higher blanching time and temperature increased water binding capacity(WBC) of chestnut powder. Water soluble index(WSI) was the highest for chestnuts blanched at $65^{\circ}C$ for 30 min. As with water binding capacity(WBC), swelling power of chestnut powder increased with increasing blanching time and temperature but solubility showed an reduction by increasing blanching temperature. In Brabender amylographic examination, peak viscosity of chestnut powder showed great change, but the gelatinization temperature showed no significant differences by blanching conditions.

• Korean journal of food and cookery science
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• v.11 no.4
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• pp.337-341
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• 1995

The effect of time and amount of water by conventional blanching method on the retention minerals in spinach and broccoli was investigated. The vegetables were blanched for 1, 2, 3 and 4 minutes, with 150 $m\ell$, 300 $m\ell$, 450 $m\ell$ of water for every 100 g of raw material. Blanching of spinach showed that Na was reduced remarkably after 2 minute of blanching, the others (K, Fe, Ca, Mg, P, Cu) were gradually decreased as the blanching time increased. Blanching of broccoli showed that the content of minerals were reduced remarkably after 1 minute of blanching. The longer blanching time further reduced the content of minerals. The retention of minerals (Na, K, Fe, Ca, Mg, P, Cu) in spinach and broccoli was reduced gradually as the blanching water increased. The retention rate of minerals were 12.7％ of Na, 37.4％ of K, 37.1％ of Fe, 43.9％ of Ca, 39.0％ of Mg, 53.5％ of P, 56.2％ of Cu in spinach and 21.0％ of Na, 41.3％ of K, 57.8％ of Fe, 38.8％ of Ca, 51.5％ of Mg, 57.7％ of P, 44.4％ of Cu in broccoli for 4 min, with water 450$m\ell$ every 100g of raw material.

• Journal of the Korean Society of Food Culture
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• v.16 no.4
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• pp.388-397
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• 2001

Wild edible plants are consumed as raw and/or processed. Analytical data for raw biologically functional compounds were relatively well established. The changes on functional compounds during processing are, however, not well studied. This study was carried out to investigate the change of the quality of wild edible plants, Pimpinella brachycarpa(Chamnamul) at various conditions. Samples were blanched at the salt concentration of 0%, 1% or 2% for 1, 2, and 3 minutes each. The biologically active compounds, vitamin C, ${\beta}-carotene$, chlorophyll, flavonoids, polyphenols and minerals were analyzed. The concentration of vitamin C in Chamnamul decreased as blanching time increased. Beta-carotene in Chamnamul showed high concentration when Chamnamul was treated under longer blanching time. Higher salt concentration of blanching water, however, resulted in the increased concentration of ${\beta}-carotene$ in the blanched Chamnamul. Higher salt concentration of blanching water also reduced the loss of total flavonoids and total polyphenols from the blanched Chamnamul. The change of colors in the blanching water seemed to be corresponding to those of total flavonoids and total polyphenols concentrations in the blanching water.

• Korean journal of food and cookery science
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• v.8 no.4
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• pp.411-419
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• 1992

Retention of ascorbic acid in vegetables as influenced by various blanching methods was measured and the effects of blanching time, amount of water added, and with or without lid on the retention were compared. It was found that blanching with small amount of water and without lid generally retained the higher activity of ascorbic acid. Although steam blanching showed the highest retention of the vitamin, the longer heating time was needed to blanch the vegetables. Blanching by microwave oven has revealed that addition of small amount of water did not affect the retention. From the scoring difference test for texture of blanched spinach, the samples which were indicated as best in texture by the 8-panel members have retained 73~96% of ascorbic acid and samples blanched by microwave oven for 60 seconds showed highest retention.

• Journal of the Korean Society of Food Culture
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• v.38 no.6
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• pp.434-441
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• 2023

This study investigated quality characteristics and antioxidant activity of beetroots after blanching. Beetroots were blanched in distilled water, 2% NaCl water, and 2% citric acid water at 100℃ for 3 minutes (the blanched group). The moisture content was highest in the control (CON) at 91.30% (p<0.05), and cooking loss was lowest in the water-blanched beetroot (BW) at 5.39% (p<0.01). Chromaticity decreased after blanching compared to CON (p<0.001). Total polyphenol contents (TPC) and total flavonoid contents (TFC) decreased after blanching, and as a result of comparing the True retention (TR) of the blanching treatment group, BW had the highest with TPC TR 91.22% and TFC TR 70.51%. DPPH and ABTS+radical scavenging activities were highest in the CON, and in the blanching group BW was highest scavenging activity. The total number of microorganisms in the CON group was 2.97 log CFU/g, whereas no microorganisms were detected in the blanched groups. Therefore, this study, blanching in water without additives is the most appropriate method for preserving physiologically active substances and nutrients in beetroots and inhibiting microbial growth.

• 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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.6
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• pp.1298-1303
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• 1999

For the purpose of improving the qualities of immatured soybean(Seoklyang), the effects of table height (0, 5, 10, 15mm) and time(60, 66, 72, 78 sec) for microwave blanching on physicochemical properties were investigated. Enzyme inactivities lipoxygenase and peroxidase for all there conditions were more de creased than for control and water blanching. Enzyme activity of each conditions was expressed as percentage on the enzyme activity of control. Lipoxygeanse activity and peroxidase activity of immatured soybeans were about 20% and 10% levels, respectively. Also the color showed the higher L(lightness), b(yellowness), chroma(brightness) values, but the lower a(redness) and hue angle. Vitamin C content was worse than for control, but was better than for water blanching. Hardness with a few exceptions showed the higher value for control.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.1
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• pp.64-69
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• 1992

To examine the effects of blanching treatments on the drying of hot red pepper, the pilot scale hot-air dryer equipped with the weight sensor using strain gauge type load cell and strain amplifier was designed and manufactured. The drying characteristic curves of cut hot red pepper showed a settling down period followed by a constant rate period and falling rate period, but blanched hot red pepper showed only falling rate period. According as the blanching time and temperature rises, the drying rates and the capsanthin contents of hot red pepper fairly increased. Considering the drying rates and the color values of dried hot red pepper, we suggest the desirable blanching condition of hot red pepper should be water blanching at $80^{\circ}C$ for 3 mins.

• Korean journal of food and cookery science
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• v.9 no.3
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• pp.204-209
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• 1993

This investigation was undertaken for the purpose of studying the chemical properties of different kinds of spinach by various blanching procedure. Ascorbic acid, mineral and oxalic acid retention of spinaches, as well as blanch effluent composition were the major factors considered with Dong-cho(winter spinach) and vinylhouse grown spinach. Ash, crude protein, crude fat and vitamin C contents of Dong-cho were higher than those of vinylhouse spinach. On the other hand, vinylhouse grown spinach showed higher content in moisture, phosporous, calcium and oxalic acid. Most of the components in spinaches were decreased by increasing the blanching water volume and time. Reducing sugar and solid content in blanch effluent of Dong-cho were increased by increasing the blanching water volume and time, however, vinylhouse spinach showed no reducing sugar.