摘要
本研究采用超声波辅助碱液提取的方法从米渣粉中提取米渣蛋白.考察超声波处理对米渣蛋白结构的影响。通过氨基酸组成分析、扫描电镜、原子力显微镜和傅立叶红外光谱分析测定米渣蛋白的氨基酸组成、蛋白形貌、聚集体和蛋白质的微观结构。从结果可以看出,超声波处理能显著提高米渣蛋白的提取率(p<0.05),在0.08mol/L的碱液浓度下,米渣蛋白质提取率达到最大值;超声波处理后达到88.44%,而不经过超声波处理的仅为43.20%;根据仪器分析结果,超声波处理能够提高疏水氨基酸的含量、改变米渣蛋白的微观结构、提高米渣颗粒的多孔性和使米渣蛋白的颗粒粒径发生变化。因此可以得出,这些结构的变化与蛋白质提取率的提高有一定的相关性,超声波辅助碱液提取是一种有效的米渣蛋白的提取方法,对米渣蛋白的工业生产也有一定的帮助。
In this study,Counter-current ultrasound-assisted alkali was employed to extract rice dreg protein(RDP) from rice dreg flour(RDF).Amino acid composition,scanning electron microscopy,atomic force microscopy and fourier transform infrared spectra were used to determine amino acid composition,morphology,aggregates and microstructure of RDP.The results indicated that ultrasound significantly improved extraction yield of RDP(p < 0.05) and extraction yield reached a maximum value at 0.08mol/L alkali concentrate.It was only 43.20%in absence of ultrasound,whereas it reached up to 88.44%under ultrasonic condition.Ultrasound treatment could result in improving of hydrophobic amino acids content and changing of RDF and RDP microstructure,showing enhancement in the porosity of RDF particle,variation of RDP particle size.Thus,the acceleration of protein extraction was related to the changes of RDF and RDP microstructure caused by ultrasound.Counter-current ultrasound-assisted alkali extraction,as a modified method,was proved to be helpful in industrial manufacture of RDP from RDF.
引文