【正文】 ic mechanical thermal analysis. This measurement simulates the physicochemical changes that take place during thermal treatment of dough. Figs. 1 and 2 show the effect of salt addition on the storage modulus (G0) during an oscillatory temperature ramp. Below 55 8C, G0, for both samples, gradually decreased as temperature increased, indicating softening of the dough. Thereafter, the storage modulus increased from 55–60 to 80 8C and then slowly decreased. The abrupt increase can be attributed to the gelatinization of starch。 indicating the physicochemical changes in heated dough are essentially due to changes in the starch fraction. For both samples the transition temperature range of salted dough appeared to be shifted to higher values than doughs made without salt (Figs. 1 and 2) as reported previously by Dreese et al. (1988) and Peressini et al. (1999). Moreover, a parison of the slopes obtained from the linear regressions over the temperature range (55–70 8C) where the G0 increased, showed that, in all cases, the slopes for salted dough were significantly lower than for unsalted doughs (Figs. 1(a) and 2(a) and Table 3). The effect of sodium chloride in delaying the starch gelatinization has been reported 機(jī)械專業(yè)中英文文 獻(xiàn)翻譯 (Chiotelli et al., 2020。 Seetharaman et al., 2020). Table 4 pares the slopes obtained from linear regressions at the different kneading conditions (in the temperature range from 55 to 70 8C) with respect to starch gelatinization. For each salt concentration it can be seen that the slopes sample M are lower that those for sample A, consequently the type of mixing seems to be relevant to the delay phenomenon. The doughs prepared using short time and highspeed mixing conditions, sample M, where high energies were transferred to the dough, were probably less hydrated and developed than sample A, therefore for starch gelatinization, for which water is indispensable, requires higher energy. The dough structure created in these kneading conditions could decrease the capability of water being effectively involved in starch granule swelling and therefore the gelatinization process is delayed. 機(jī)械專業(yè)中英文文 獻(xiàn)翻譯 氯化鈉、混合時間及設(shè)備對面團(tuán)的熱力學(xué)特性的影響 摘要 ： 在不同揉捏條件和加入不同數(shù)量氯化鈉條件下對麥粉的熱力學(xué)性能進(jìn)行了測試?；旌线^程如何進(jìn)行、各成分如何進(jìn)行合并分解很大程度上決定了烘焙產(chǎn)品的最終質(zhì)量（阿莫特等， 2020?；旌线^程有三個重要作用： 使各組成成分混合成宏觀上同質(zhì)的物質(zhì)； 使面團(tuán)變成內(nèi)含氣體的三維有粘彈性結(jié)構(gòu)的物質(zhì)； 包含在面團(tuán)發(fā)酵時為氣泡變大提供核心的空氣（布蘭克， 1990；克拉多及萊納， 2020；多布羅斯科克 及 摩根斯頓 ， 2020； 侯賽因及 羅杰斯， 1990；納伊姆 等， 2020）。生面團(tuán)在高速混合器中混合時，需要很高的條件才能形成有彈性、混合均勻的整體。 淀粉，面粉的主要成分，占其干重的 80%左右，影響生面團(tuán)的流變學(xué)性質(zhì)，特別是淀粉糊化時在暖氣設(shè)備中有水存在 (李、葉， 2020)。再者，當(dāng)在生面團(tuán)中加入食鹽時，熱誘導(dǎo)比如淀粉糊化和蛋白質(zhì)凝結(jié)會變慢。根據(jù)面筋拉力測定儀 AACC 5430A (2020)方法，使用兩種不同的混合器和兩種不同的混合時間，準(zhǔn)備好兩個含 50%水分的生面團(tuán)樣本。為每種不同的揉捏條件和混合器類型加入 （表 1）。 a 加水使生面團(tuán)含水量 50% 熱機(jī)械的測試用一個受控制的應(yīng)力 應(yīng)變流變儀（ MCR 300，物理學(xué) /安東帕） 和平行板幾何（板直徑 25cm,間隙 2mm）完成。 在升溫速度為 ℃ /分，頻率穩(wěn)定在 1Hz振蕩幅度足夠小而不致影響線性粘彈性的情況下完成測試。 1. 結(jié)果與討論 面粉 的化學(xué)、物理特性 面粉化學(xué)成分和流變特性如表 2 所示。不同揉捏條件這種測試模擬在生面團(tuán)熱處理中的物理化學(xué)變化。麥谷蛋白分解，二硫化物 /氫硫基互換反應(yīng)加劇，因此增大了分子的大?。ǖ吕锼沟?， 1988；帕諾斯尼等， 1999）。并且，在 G’上升的 5570℃ 獲取的線性衰退斜率對比表明放鹽的面團(tuán)斜率明顯低于沒放鹽的生面團(tuán)斜率（圖 1(a)和 2（ a）、表 3）。可以發(fā)現(xiàn)，在每個食鹽比例條件下樣本 M 的斜率比同條件下的樣本 A要小，所以混合的類型看來跟延遲這一現(xiàn)象有關(guān)。它們還表明生面團(tuán)的淀機(jī)械專業(yè)中英文文 獻(xiàn)翻譯 粉膠凝和蛋白質(zhì)凝結(jié)反應(yīng)因加入食鹽這一條件被延遲，在雛形混合器高速揉捏得到的面團(tuán)效果更