以機械壓榨方式製作之脫脂大豆胚軸理化性質之探討

A study of physicochemical properties of defatted soybean hypocotyl manufactured by mechanical pressing

薛文彬(Wen-Pin Hsueh)

指導教授 ： 林貞信 博士

國立屏東科技大學/農學院/食品科學系所/碩士(2008年)

摘要

大豆包含許多對健康有益的植物化合物，尤其是大豆異黃酮，已有諸多文獻證明大豆具有預防心血管疾病、癌症、骨質疏鬆症及減少更年期不適症狀等功能。但是隨著時代的進步，國家經濟的發展，國民不論在生活水準及營養觀念上，均有質與量的提升，也不再以直接食用大豆為主。因此各種大豆加工及萃取機能性質之物質方式不斷進步，尤其是脫脂大豆粉可直接添加於食品製程中，提供豐富的蛋白質。為符合現代崇尚天然的風氣，本研究採用的原料為大豆胚軸，它不但含有高蛋白質更有豐富的異黃酮，利用浸漬、加壓蒸煮及壓榨等加工方式製作脫脂大豆胚軸，探討不同浸漬溫度(30、40、50、60 ˚C) 、不同浸漬時間(0、2、4、8、12 h )及不同加壓蒸煮時間(5、30、60 min)，對脫脂大豆胚軸理化性質(水分、灰分、粗脂肪、粗蛋白、色差、異黃酮(daidzin、genistin、daidzein、genistein))含量的影響。實驗結果顯示：大豆胚軸於30˚C水中時，浸漬過水、加壓蒸煮5 min，再壓榨乾燥後，粗脂肪含量即可低至6.91 %。隨著浸漬溫度及浸漬時間的增加及加壓蒸煮時間的增加，粗脂肪含量之相對比例亦升高。至於色澤方面，除了30˚C時，浸漬加壓蒸煮變數交互項對於b值及40˚C時浸漬蒸煮變數交互項對L值沒有顯著影響外，實驗結果顯示浸漬蒸煮變數對L、a、b值均有顯著影響。在異黃酮方面，大豆胚軸以40 ˚C浸漬12 h，daidzein最高含量為2866.67 ppm，50 ˚C浸漬12 h ，genistein最高含量為830 ppm。加壓蒸煮加工對於四種異黃酮個別含量均有極顯著的影響。進行壓榨後，在浸漬時間(0、2、4、8、12 h ) 、加壓蒸煮5 min 條件下的四種異黃酮含量總和均減少，浸漬時間(2、4、8、12 h )、加壓蒸煮30 min及60 min條件下的四種異黃酮含量總和均增加。熱風乾燥對於四種異黃酮總含量的增加有顯著影響。最後則是相同浸漬溫度下，浸漬時間與加壓蒸煮時間對水分及粗蛋白含量皆有顯著影響，至於對灰分含量的影響，則不顯著。

關鍵字：大豆異黃酮、機能性質、大豆胚軸、浸漬、蒸煮、壓榨

關鍵字

大豆異黃酮 ； 機能性質 ； 大豆胚軸 ； 浸漬 ； 蒸煮 ； 壓榨

並列摘要

Recently, numerous literature reported that soybean contains several health-benefiting phytochemicals which past evidences had proved that it is related to the cardiovascular diseases prevention, cancer, osteoporosis and relieving menopause symptom, in particular isoflavones. With progress of society and development of national economic, the level of living and the concept of nutrition of citizen has raised not only quantify but also qualifiedly. Thus, people not longer consume soybean directly. Therefore, methods for functional material processing and extract are improving unceasingly. In particularly, the defatted soybean flour can be directly added in food processing and thus provides rich protein. In order to pursue nature, the soybean hypocotyls was used as material in this study, not only it includes the high protein but the rich isoflavones, which processed by soaking, cooking and pressing in order to produce defatted soybean hypocotyls. The effects of different soaking temperature (30, 40, 50, 60℃), soaking time (0, 2, 4, 8, 12 h) and cooking time (5, 30, 60 min) on the physicochemical properties (moisture contents, ash contents, crude fat contents, crude protein contents, isoflavone contents (including daidzin, genistin, daidzein, genistein)) of defatted soybean hypocotyls were investigated. The results showed that soybean hypocotyls under 30˚C water temperature, washed and cooked for 5 minutes then dried by mechanical pressing, crude fat content would be reduced to 6.91 %. However, with the increasing of soaking temperature, soaking time and cooking time result in the crude fat content would be also increased fast. As to the color differences
, the results showed that there were significant effects between soaking variable and L, a and b value, except at 30˚C of soaking showed no significant effects between cooking variable and b value, no significant between 40˚C soaking and cooking variable and L value. In isoflavone content, after soaking at 40℃ for 12 hours, daidzein content was 2866.67 ppm, and genistein content was 830 ppm at 50℃ of soaking for 12 hours. Daidzin, genistin, daidzein and genistein were affected significantly by cooking variable. After mechanical pressing, under soaking time (0, 2, 4, 8, 12 h) and cooking time (5 min), the sum of four varieties of isoflavone contents were reduced. However, under soaking time (2, 4, 8, 12 h) and cooking time (30, 60 min), the sum of four varieties of isoflavone contents was increased. There was significant effect on the increasment of four varieties isoflavone contents after hot-air drying. When under the same temperature, both soaking time and cooking time had the remarkable effects on the moisture and crude protein contents but not ash content.

Key words: soybean isoflavone, functional property, soybean hypocotyls, soaking, cooking, pressing

並列關鍵字

soybean isoflavone ； functional property ； soybean hypocotyls ； soaking ； cooking ； pressing

參考文獻

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