Jiménez Antonio, Rufo Montaña, Paniagua Jesús M, Crespo Abel T, Guerrero M Patricia, Riballo M José
Department of Applied Physics, School of Technology, University of Extremadura, Avenida de la Universidad, s/n, 10003 Cáceres, Spain.
Department of Applied Physics, School of Technology, University of Extremadura, Avenida de la Universidad, s/n, 10003 Cáceres, Spain.
Ultrasonics. 2017 Apr;76:192-199. doi: 10.1016/j.ultras.2017.01.007. Epub 2017 Jan 10.
Ultrasound evaluation permits the state of milk being curdled to be determined quickly and cheaply, thus satisfying the demands faced by today's dairy product producers. This paper describes the non-invasive ultrasonic method of in situ monitoring the changing physical properties of milk during the renneting process. The basic objectives of the study were, on the one hand, to confirm the usefulness of conventional non-destructive ultrasonic testing (time-of-flight and attenuation of the ultrasound waves) in monitoring the process in the case of ewe's milk, and, on the other, to include other ultrasound parameters which have not previously been considered in studies on this topic, in particular, parameters provided by the Fast Fourier Transform technique. The experimental study was carried out in a dairy industry environment on four 52-l samples of raw milk in which were immersed 500kHz ultrasound transducers. Other physicochemical parameters of the raw milk (pH, dry matter, protein, Gerber fat test, and lactose) were measured, as also were the pH and temperature of the curdled samples simultaneously with the ultrasound tests. Another contribution of this study is the linear correlation analysis of the aforementioned ultrasound parameters and the physicochemical properties of the curdled milk.
超声评估能够快速且低成本地确定牛奶的凝固状态，从而满足当今乳制品生产商所面临的需求。本文描述了一种非侵入性超声方法，用于原位监测凝乳酶作用过程中牛奶物理性质的变化。该研究的基本目标，一方面是确认传统无损超声检测（超声波的飞行时间和衰减）在监测羊奶凝乳过程中的有效性，另一方面是纳入此前该主题研究中未考虑的其他超声参数，特别是快速傅里叶变换技术提供的参数。实验研究是在乳制品工业环境中对四个52升的原料乳样本进行的，其中浸入了500kHz的超声换能器。同时测量了原料乳的其他理化参数（pH值、干物质、蛋白质、盖勃氏脂肪测定、乳糖）以及凝乳样本的pH值和温度，与超声测试同步进行。本研究的另一个贡献是对上述超声参数与凝乳的理化性质进行线性相关分析。
