Elmehdi H M, Scanlon M G, Page J H, Kovacs M I P
Department of Applied Physics, University of Sharjah, Sharjah, PO Box 27272, United Arab Emirates.
Department of Food Science, University of Manitoba, Winnipeg, MB R3T 2N2 Canada.
J Ultrasound. 2013 Jun 6;16(3):101-10. doi: 10.1007/s40477-013-0022-0.
To probe the thermal and structural properties of gluten proteins using ultrasound.
A new ultrasonic approach for characterizing the quality of wheat gluten proteins is described. Low frequency (50 kHz) longitudinal ultrasonic velocity, v L, measurements were performed on gluten samples extracted from three wheat flours differing in protein content and in wheat endosperm hardness.
At room temperature, v L for gluten extracted from soft flowers (Fielder) was found to be (870 ± 92) m/s, while for gluten extracted from extra strong flours (Glenlea) it was found to be (1,940 ± 90) m/s. In the second set of experiments, which aimed at probing thermal properties of gluten proteins, the variation in the numerical value of v L propagating in the wet gluten was found to be substantial (about 1,000 m/s) when the temperature of the gluten was raised from 20 to 90 °C, and also when gluten from different flour types was investigated. A continuous structural phase transition was observed, which was different for glutens extracted from different flours. Upon cooling, the velocity also varied depending on wheat type.
These experiments demonstrate that ultrasonic velocity measurements can be used as a selection tool and study changes in properties of wheat proteins, particularly the thermal transitions that are critical to the quality of end products such as noodles, pasta, and bread. It was also shown that v L is sensitive to gluten class (strength or protein content), showing the potential of such measurements as an early-generation selection tool in wheat breeding programs.
利用超声探测面筋蛋白的热性能和结构性能。
描述了一种用于表征小麦面筋蛋白质量的新型超声方法。对从三种蛋白质含量和小麦胚乳硬度不同的小麦粉中提取的面筋样品进行了低频（50 kHz）纵向超声速度vL测量。
在室温下，从软质小麦粉（菲尔德）中提取的面筋的vL为（870±92）米/秒，而从超强筋小麦粉（格伦利厄）中提取的面筋的vL为（1940±90）米/秒。在旨在探测面筋蛋白热性能的第二组实验中，当面筋温度从20℃升高到90℃时，以及在研究不同面粉类型的面筋时，发现湿面筋中传播的vL数值变化很大（约1000米/秒）。观察到连续的结构相变，不同面粉提取的面筋的相变不同。冷却时，速度也因小麦类型而异。
这些实验表明，超声速度测量可作为一种选择工具，用于研究小麦蛋白的性能变化，特别是对面条、意大利面和面包等最终产品质量至关重要的热转变。还表明vL对面筋类别（强度或蛋白质含量）敏感，显示了这种测量作为小麦育种计划早期选择工具的潜力。
