Leiva-Valenzuela Gabriel A, Quilaqueo Marcela, Lagos Daniela, Estay Danilo, Pedreschi Franco
1Department of Chemical and Bioprocess Engineering, Pontificia Universidad Católica de Chile, Avenida Vicuña Mackenna 4860, Macul, Santiago, Chile.
2Department of Chemical Engineering, Universidad de La Frontera, Avenida Francisco Salazar 01145, Temuco, Chile.
J Food Sci Technol. 2018 Apr;55(4):1234-1243. doi: 10.1007/s13197-017-3008-7. Epub 2018 Feb 20.
The aim of this research was to determine the effect of composition (dietary fiber = DF, fat = F, and gluten = G) and baking time on the target microstructural parameters that were observed using images of potato and wheat starch biscuits. Microstructures were studied Scanning Electron Microscope (SEM). Non-enzymatic browning (NEB) was assessed using color image analysis. Texture and moisture analysis was performed to have a better understanding of the baking process. Analysis of images revealed that the starch granules retained their native form at the end of baking, suggesting their in complete gelatinization. Granules size was similar at several different baking times, with an average equivalent diameter of 9 and 27 µm for wheat and potato starch, respectively. However, samples with different levels of DF and G increased circularity during baking to more than 30%, and also increasing hardness. NEB developed during baking, with the maximum increase observed between 13 and 19 min. This was reflected in decreased luminosity (L*) values due to a decrease in moisture levels. After 19 min, luminosity did not vary significantly. The ingredients that are used, as well as their quantities, can affect sample L* values. Therefore, choosing the correct ingredients and quantities can lead to different microstructures in the biscuits, with varying amounts of NEB products.
本研究的目的是确定成分(膳食纤维=DF、脂肪=F和麸质=G)和烘焙时间对使用马铃薯和小麦淀粉饼干图像观察到的目标微观结构参数的影响。使用扫描电子显微镜(SEM)研究微观结构。使用彩色图像分析评估非酶褐变(NEB)。进行质地和水分分析以更好地了解烘焙过程。图像分析表明,淀粉颗粒在烘焙结束时保持其天然形态,表明它们未完全糊化。在几个不同的烘焙时间,颗粒大小相似,小麦和马铃薯淀粉的平均等效直径分别为9和27μm。然而,不同DF和G含量的样品在烘焙过程中圆形度增加到30%以上,硬度也增加。烘焙过程中发生了NEB,在13至19分钟之间观察到最大增加。这反映在由于水分含量降低导致的亮度(L*)值下降。19分钟后,亮度没有显著变化。所使用的成分及其数量会影响样品的L*值。因此,选择正确的成分和数量会导致饼干中出现不同的微观结构,以及不同数量的NEB产物。