Laboratory of Food Engineering, School of Food and Nutritional Sciences, University of Shizuoka, Shizuoka, Japan.
Food Technology Section, Industrial Research Institute of Shizuoka Prefecture, Shizuoka, Japan.
J Sci Food Agric. 2023 Jun;103(8):3822-3829. doi: 10.1002/jsfa.12288. Epub 2022 Nov 10.
Soymilk is utilized not only as a beverage but also as an alternative to bovine milk, including products such as yoghurt and cream. Evaporated soymilk is expected to be utilized as condensed milk. Raw and heated soymilk samples prepared in our laboratory were evaporated and then subjected to viscosity measurement. The soymilk samples were made from two different varieties: Fukuyutaka, which contains 7S and 11S globulin proteins; and an 11S-lacking soybean (Nanahomare).
Raw Fukuyutaka soymilk had a lower viscosity and could be concentrated to a solids content of over 300 g kg compared to heated soymilk (around 250 g kg ), but the viscosity changes of Nanahomare soymilk showed an opposite trend. Only 7S globulin was denatured during evaporation at 75 °C and likely affected the interaction between proteins and oil bodies. This tendency was remarkable in the Nanahomare soymilk. The strange viscosity change behavior of evaporated Nanahomare soymilk, number of protein particles, intrinsic fluorescence and flow behavior suggest that thermally denatured 7S globulin accelerates the interactions between oil bodies, whereas 11S globulin, which is probably in its native state, suppresses the acceleration by denatured 7S globulin.
Raw soymilk containing native globulins shows a slower increase in viscosity during evaporation. However, denatured 7S globulin accelerates the increase in viscosity during evaporation through interactions between oil bodies. The effect of the denatured state of individual proteins on interactions is expected to be useful in understanding the interaction between proteins and in controlling their properties and functions. © 2022 Society of Chemical Industry.
豆浆不仅可以作为饮料，还可以替代牛奶，包括酸奶和奶油等产品。浓缩乳中预计会用到蒸发豆浆。我们实验室制备的生豆浆和热豆浆样品经过蒸发后进行了黏度测量。这些豆浆样品由两种不同的品种制成：福谷大豆，含有 7S 和 11S 球蛋白；以及一种缺乏 11S 的大豆（Nanahomare）。
与生豆浆相比，生福谷豆浆的黏度较低，可以浓缩至超过 300g/kg 的固形物含量（热豆浆约为 250g/kg），但 Nanahomare 豆浆的黏度变化则呈现相反的趋势。只有在 75°C 蒸发时 7S 球蛋白发生变性，可能影响蛋白质与油体之间的相互作用。这种趋势在 Nanahomare 豆浆中尤为明显。在蒸发过程中，变性的 7S 球蛋白会显著改变 Nanahomare 豆浆的黏度变化行为、蛋白质颗粒数、固有荧光和流动行为，表明其可能加速油体之间的相互作用，而可能处于天然状态的 11S 球蛋白则可能抑制变性 7S 球蛋白引起的加速作用。
含有天然球蛋白的生豆浆在蒸发过程中黏度增加较慢。然而，变性的 7S 球蛋白通过油体之间的相互作用加速了蒸发过程中黏度的增加。研究个别蛋白质变性状态对相互作用的影响，有望有助于理解蛋白质之间的相互作用，并控制其性质和功能。 © 2022 英国化学学会。
