Effect of ultrasonic treatment on the structure and functional properties of protein-fortified potato powder

Abstract

Potato powder has substantial nutritional value and gluten-free protein, making it an ideal ingredient in gluten-free foods that meet the dietary requirements of individuals with gluten allergies. However, the absence of gluten protein limits the processing and utilization of potato powder-based products. Different levels of power density (1–5 W/cm³) was used on potato powder enriched with whey protein and determine the impact of structural and functional characteristics by CLSM, FTIR spectroscopy, X-ray diffraction, low-field nuclear magnetic resonance and thermogravimetric analyses. The results showed that ultrasonic treatment destroyed the structures of starch and protein in protein-fortified potato powder, resulting in smaller starch granules. Compared with the blank group, the amylose content increased by 0.13-fold, relative crystallinity (RC) increased to 15.9%, water absorption capacity increased by 36% and oil absorption capacity increased by 112.5%. Ultrasonic treatment increased the contents of disulfide bonds, α-helices and β-sheets in protein-enhanced potato powder; improved the strength and construction rate of the protein network structure; promote the transformation of immobilized-water to bound-water and reduce the water mobility of dough and increased the hardness of protein-enhanced potato powder gel by 1.5-fold. In contrast, excessive ultrasonic power had a negative effect while consuming energy.