第二十屆上海國(guó)際淀粉及淀粉衍生物展覽會(huì)

淀粉通常被添加到湯等食物中，使其變得更濃稠，但這樣做會(huì)增加卡路里和碳水化合物含量。
現(xiàn)在，美國(guó)康奈爾大學(xué)的研究人員發(fā)現(xiàn)，通過(guò)將淀粉顆粒排列成特殊形狀，可以將它們變成超級(jí)增稠劑，同時(shí)在不犧牲口感的情況下減少食物中的淀粉含量。
2月16日，相關(guān)研究成果發(fā)表于《科學(xué)進(jìn)展》。淀粉是面粉的一種成分，是烹飪中使用的增稠劑。淀粉顆粒使食物變稠是因?yàn)樗鼈兪軣釙r(shí)會(huì)膨脹。這意味著顆粒會(huì)相互擠壓，從而使液體成分自由流動(dòng)的空間變小。研究人員想知道他們是否可以復(fù)制這種效果“問(wèn)題在于不能像雕刻南瓜一樣雕刻淀粉顆粒。”論文作者之一、康奈爾大學(xué)的李培龍說(shuō)。

原文
We built superstructures using amaranth starch granules as building blocks via a Pickering emulsion approach (Fig. 2A). We first extracted amaranth starch from amaranth flour in such a way that we retained some native proteins. The small size (~1 μm), high protein content (2.4%), and tunable softness of this high-protein amaranth starch make it the best candidate for building fused superstructures using this approach, and was therefore used as our building block for the entire study (21). These high-protein starch granules, being moderately hydrophobic, will position themselves around an oil droplet at the oil/water (O/W) interface during emulsification via high-shear homogenization [Fig. 2A(2)] (21). If no heat treatment is conducted after emulsification, and we remove both the inner (oil) and outer (water) phases by freeze-drying, the adjacent starch granules that originally surrounded the oil droplet will peel off into 2D sheets [Fig. 2A(3a)], which can then be cross-linked to reinforce them [Fig. 2A(4a)]. The size of these sheets can be controlled; for example, by increasing the homogenization speed, smaller oil droplets are formed, which reduce the size of the sheets. Alternatively, if controlled heating is briefly applied after emulsification, but before freeze-drying, adjacent starch granules surrounding the oil droplet become fused together to form a strong hollow 3D cage after removal of both the inner and outer phases [Fig. 2A(3b)], which can then also be cross-linked [Fig. 2A(4b)]. We investigated these superstructures in terms of their morphology, spatial and structural (molecular) conformation, water-holding capacity (WHC), critical caking concentration (CCC), and viscosity, along with the effect of method parameters such as heating temperature and heating time on cage morphology and crystallinity.