• Title, Summary, Keyword: blanching

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Effects of Low-temperature Blanching on Physical Properties of Chestnut Powder (Low-temperature Blanching 처리가 밤가루의 물리적 특성에 미치는 영향)

  • Lim, Jeong-Ho;Kim, Jun-Han;Seo, Young-Ho;Moon, Kwang-Deog
    • 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.

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Changes in physicochemical properties of Peucedanum japonicum Thunb. after blanching (Blanching에 따른 갯기름 나물의 이화학적 특성 변화)

  • Son, Hee-Kyoung;Kang, Su-Tae;Jung, Hae-Ok;Lee, Jae-Joon
    • Korean Journal of Food 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.

Quality Characteristics of Frozen Welsh Onion (Allium fistulosum L.) according to Various Blanching Treatment Conditions (Blanching 처리 조건에 따른 동결 대파의 품질 특성)

  • Lee, Hye-Ok;Lee, Young-Joo;Kim, Ji-Young;Yoon, Doo-Hyun;Kim, Byeong-Sam
    • 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).

Changes in Physicochemical Properties of Spergularia marina Griseb by Blanching (Blanching에 따른 세발나물의 이화학적 특성 변화)

  • Lee, Jae-Joon;Jung, Hae-Ok
    • Korean Journal of Food 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.

Effects of Blanching, Chemical Dipping, Freezing Methods and Storage Period on Quality of Frozen Mushrooms (Blanching, Chemical Dipping, 냉동방법 및 저장기간이 냉동 양송이의 품질에 미치는 영향)

  • Lee, Young-Chun;Lee, Kyung-Hae
    • Korean Journal of Food Science and Technology
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    • v.20 no.4
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    • pp.536-540
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    • 1988
  • Effects of blanching time, chemical dipping, freezing method and storage period on texture, color and yield of frozen whole and sliced mushrooms were investigated, and the results are summarized as follows; Frozen whole mushrooms blanched for 5min. had markedly tougher texture than mushrooms blanched for 1 or 2 minutes. As the storage time of frozen mushrooms increased from 3 to 6 months, shear press values increased very significantly. The texture of Freon frozen and plate frozen mushrooms was similar after 3 months storage. Blanching time did not affect texture of frozen sliced mushrooms significantly, but storage time did. The results of sensory evaluation for texture were in good agreement with shear press values. Chemical dipping methods were effective in maintaining desirable color of frozen whole and sliced mushrooms stored for 3 months. The yield of frozen whole mushrooms was significantly increased by shortening blanching time in combination with chemical dipping. Sliced mushrooms required at least 2 min. blanching, to avoid excessive breakage in mechanical slicing operation, for better yield.

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The Blanching Effects on the Drying Rates and the Color of Hot Red Pepper (고추의 건조율 및 색도에 미치는 Blanching 효과)

  • Chung, Shin-Kyo;Shin, Jong-Chul;Choi, Jong-Uck
    • 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.

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Changes in Physicochemical Properties of Haetsun Vegetables by Blanching (Blanching에 의한 햇순나물의 이화학적 특성 변화)

  • Kim, Min-Ha;Jang, Hye-Lim;Yoon, Kyung-Young
    • 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.

Quality characteristics of outer leaves of Kimchi cabbage according to various blanching treatment conditions (국내산 배추 우거지의 blanching 처리에 따른 품질 특성)

  • Hong, Joo-Heon;Hwang, Tae-Young
    • Korean Journal of Food 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.

Effects of Blanching Conditions on the Quality of Immatured Soybeans during Frozen Storage (냉동저장동안 풋콩의 품질에 영향을 미치는 Blanching 조건)

  • Hong, Ju-Heon;Bae, Dong-Ho;Choe, Yong-Hui
    • Korean Journal of Food 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.

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Changes in Phytochemical Compounds and Hazardous Factors of Spinach by Blanching Methods (데치는 방법에 따른 시금치의 phytochemical 성분 및 위해성 요인 변화)

  • Hong, Jeong-Jin;Ahn, Tae-Hyun
    • Korean Journal of Food Science and Technology
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    • v.37 no.2
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    • pp.268-273
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    • 2005
  • Changes in contents of phytochemical compounds (${\beta}$-carotene, ascorbic acid, chlorophylls, total flavonoid, total polyphenol) and hazardous factors (microbial counts, nitrate) of spinach (Spinacia oleracia L.) were investigated by conventional and microwave blanching methods. ${\beta}$-Carotene and chlorophylls contents of spinach were significantly increased by blanching, with conventional blanching resulting in higher contents than microwave blanching. In contrast, contents of ascorbic acid, total flavonoid, and total polyphenol of blanched spinach decreased, with microwave blanching resulting in higher ascorbic acid, total flavonoid, and total polyphenol contents than conventional blanching. Total plate count and total coliforms of blanched spinach significantly decreased, with conventional blanching showing less than 20-25% of microwave blanching. Nitrate content of blanched spinach also showed decreasing pattern, with decrease due to microwave blanching being lower, although not significantly, than that of conventional blanching.