Mapping Moisture Sorption Through Carbohydrate Composite Glass with Fourier Transform Near-Infrared (FT-NIR) Hyperspectral Imaging
Mapping Moisture Sorption Through Carbohydrate Composite Glass with Fourier Transform Near-Infrared (FT-NIR) Hyperspectral Imaging
复制标题
利用傅里叶变换近红外 (FT-NIR) 高光谱成像绘制碳水化合物复合玻璃的吸湿图
作者：
C. M. Nowakowski;W. Aimutis;S. Helstad;D. Elmore;Allen Muroski
食品在储存过程中的固有变化通常是由于水的吸附或解吸引起的，这往往会导致产品基质的不稳定。吸水行为因基质的不同而不同。通常，结晶等同时发生的现象会改变水的运动。我们描述了一种结合高光谱成像和傅立叶变换近红外(FT-NIR)光谱的新用途，以绘制水分子在二维中的位置，同时量化结晶基元，在一个月的储存时间内将水吸收到碳水化合物基质中。这种方法使我们能够识别和量化在碳水化合物基质中形成的蔗糖晶体，同时还可以绘制通过这个复杂基质的水迁移图。我们比较了蔗糖过饱和(高蔗糖，HS)、蔗糖低于饱和(低蔗糖，LS)、蔗糖低于饱和与蔗糖晶体(LSS)以及麦芽三糖在玉米糖浆基质(高麦芽三糖，LSM)中过饱和的玉米糖浆/蔗糖混合物。这种FT-NIR方法被用来表征随着时间的推移碳水化合物基质对水的吸附，并测量了体系形成蔗糖晶体的倾向以及蔗糖晶体对水吸附的影响。我们观察到水在低糖碳水化合物玻璃中的扩散较慢，吸附过程也不同。在蔗糖中过饱和的非晶态体系在吸附足够的水时允许结晶，因此，这种同时发生的作用破坏了正常的费克扩散。当水锋通过基质吸收时，它被压缩成一个窄带。嵌入在无定形基质中的晶体的存在通过使移动的水分子的路径卷曲来减缓水在基质中的整体渗透。这似乎并没有改变扩散的速度。过饱和浓度麦芽三糖的结晶速度慢于蔗糖。因此，作为蔗糖的潜在替代品，纯麦芽三糖并不是一种实用的解决方案，可以减缓食品系统中的吸收。
Inherent changes in foods during storage are often caused by water sorption or desorption that often results in product matrix instability. Water sorption behavior differs depending on the matrix through which it moves. Often, concurrent phenomenon such as crystallization modifies water’s movement. We describe a novel use of hyperspectral imaging combined with Fourier Transform Near Infrared (FT-NIR) spectroscopy to map where water molecules are in two dimensions while concurrently quantifying the crystallization motif as water sorbs into a carbohydrate matrix over a month’s storage time. This methodology allows us to identify and quantify sucrose crystals formed within a carbohydrate matrix while also mapping water migration through this complex matrix. We compared corn syrup/sucrose blends where sucrose is supersaturated (high sucrose, HS), sucrose is below saturation (low sucrose, LS), sucrose below saturation with embedded sucrose crystals (LSS) and maltotriose is supersaturated within a corn syrup matrix (high maltotriose, LSM). This FT-NIR method was used to characterize water sorption through a carbohydrate matrix over time and measured both the propensity of the systems to form sucrose crystals and the influence sucrose crystals have on water sorption. We observed water diffusion was slower in lower sugar carbohydrate glasses, and the process of sorption was different. Amorphous systems supersaturated in sucrose allow crystallization when sufficient water is sorbed and thus, this concurrent action disrupts normal Fickian diffusion. The water front compresses to a narrow band as it sorbs through the matrix. The presence of embedded crystals in an amorphous matrix slows overall water penetration through the matrix by convoluting the path of moving water molecules. This did not appear to change the rate of diffusion. Experiments with maltotriose at supersaturation concentration showed the crystallization rate was slower than sucrose. Thus, pure maltotriose is not a practical solution as a potential replacement for sucrose to slow sorption in food systems.
糖玻璃的傅里叶变换红外光谱研究。
影响因子：
3.1
作者：
Wolkers,WillemF;Oliver,AnnE;Tablin,Fern;Crowe,JohnH
通讯作者：
Crowe,JohnH