焙烤裹衣花生加工工艺的研究

本实验是在美国乔治亚大学食品安全和品质改良中心进行的。研究出一种裹衣花生新配方及加工工艺。对裹衣花生加工过程中有关影响因素的作用进行了研究。裹衣花生的裹衣层重占５０％为佳。膨松粉与裹衣糖浆的适宜比例为１３：１。裹衣层间隔７分钟为宜。焙烤温度和时间对裹衣花生产品的质量影响很大。裹衣占４２％ ，焙烤温度１６５℃、４０ 分钟和１５５℃、４５ 分钟较好；裹衣占５８％ ，温度１７５℃、４５ 分钟为好；裹衣占５０％ ，以温度１７５℃、４５ 分钟或１６５℃、５０ 分钟为好。

焙烤处理对发芽糙米生理活性物质及抗氧化活性的影响

为探究焙烤处理对发芽糙米生理活性物质及抗氧化活性的影响,为开发焙烤类发芽糙米产品提供理论依据,以发芽糙米为研究对象,研究焙烤温度(125～175℃)和焙烤时间(15～30 min)对发芽糙米中γ-氨基丁酸、植酸、谷维素、抗氧化物质及抗氧化活性的影响。结果表明,150℃焙烤后的发芽糙米与其它温度相比,γ-氨基丁酸(GABA)损失率最小,植酸降解率与谷维素增加量较大,抗氧化物质与抗氧化活性下降较小;随着焙烤时间的增长,发芽糙米中的生理活性物质均呈不同程度的下降趋势,抗氧化物质及抗氧化活性显著下降(p<0.05),其中,焙烤15 min时,发芽糙米中GABA损失了5.58%,植酸降解率为43.53%,谷维素含量增加了21.54%;游离酚、结合酚和黄酮的下降程度分别为16.77%、18.54%和20.30%;在抗氧化活性方面,DPPH自由基清除率、ABTS清除率、FRAP值和ORAC值分别下降了14.77%、13.60%、9.10%和19.86%。因此,150℃焙烤15 min能最大限度地保持发芽糙米的生理活性物质和抗氧化活性。

Various Temperature of Vacuum and Conventional Roasting on Color Alteration and Polyphenols Content of Cocoa Powder

This study has the objective to found out the temperature and raosting time of cocoa powder in order to gain color, aroma and taste favored by the panelist and has high polyphenol content. The roasting time in this research has been determined 35 min, and roasting temperature of 80, 90, 100, 110, 120, 130, 140 and 150 ℃ with vacuum and conventional system. From those temperatures ranges, we would take the three best levels according to organoleptic test result. The three selected temperatures would be tested for changing in polyphenol content during roasting process. Color alteration would be physically analyzed using color reader （PCE-RGB）. However, phenol total content was analyzed using colorimetric method of Folin-Ciocalteu. Result of this study showed that color alteration percentage （RGB model analysis） during conventional roasting is higher （43%） compared with vacuum roasting system （2%） Subsequently, organoleptic test result showed that from roasting temperatures between 80 ℃ and 150 ℃, cocoa powder favored by the panelist were those that was treated in temperature 100 ℃, 110 ℃ and 120 ℃. Other results indicated that vacuum roasting implementation could increase polyphenol content. While vacuum roasting of 60.8 cm Hg in 120 ℃ with roasting time of 25 min has obtained 10.57% total phenolic, or increasing as much as 1.22%.