超声与高压微射流处理对大豆分离蛋白微细化的影响

研究超声功率与时间和高压微射流操作压力与次数件对乳液温升、加权平均粒径和粒度分布等的影响,以寻找适合不同工艺需求的大豆分离蛋白物理改性方法。结果表明,经超声处理SPI乳液粒径呈现双峰分布,经高压微射流处理SPI乳液粒径呈单峰分布,说明高压微射流比超声处理的乳化均匀一致性好。超声(1200 W)能够提高SPI乳液的均匀一致性和乳化稳定性,但SPI微团尺寸缩减能力有限,处理时间过长则乳液发生再凝聚,出现SPI微团尺寸增大的现象。当乳液粒径较大(10~(-4) m级)时,瞬时(10~(-6) s级)高压微射流(35 MPa以上)处理形成高能量密度能够达到较好的微细化结果,加权平均粒径D_([3,2])和D_([4,3])显著减小。

Study on micronization of SPI emulsions by ultrasonication and microfluidization techniques

The purpose of the study was to produce soy protein isolate(SPI) micro emulsion droplet by ultrasonication and microfluidization Techniques. The changes of SPI emulsion temperature, average droplet diameter and size distribution were observed. The distribution curve of SPI droplet processed by ultrasonication has two peaks and that of SPI droplet processed by microfluidization has single peak. The results indicate that the SPI emulsion processed by high pressure is more homogeneous. The capability of reducing size by ultrasonic process (1 200 W) is very limited, and the SPI emulsion tends to agglomerate after a long time of ultrasonic process. Microfluidization (microseconds, 35 MPa) can provide high energy and has the rather better affection for micronizing the treated SPI emulsion (hundred micrometers), and the mean droplet diameter D_[3,2] and D_[4,3] are exponentially shortened.