Effects of high hydrostatic pressure on the physicochemical and emulsifying properties of sweet potato protein

Abstract

Summary The influence of high hydrostatic pressure (HHP) treatment on the physicochemical and emulsifying properties of sweet potato protein (SPP) at various concentrations, e.g. 2%, 4% and 6% (w/v, SPP‐2, SPP‐4 and SPP‐6), was investigated. Significant differences in hydrophobicity, enthalpy of denaturation and solubility were observed (P < 0.05). Emulsifying activity indexes (EAI) of SPP‐2 and SPP‐6 increased at 400 MPa, whereas EAI of all SPP significantly decreased at 600 MPa (P < 0.05). Emulsion stability (ESI) was significantly decreased for SPP‐2 and SPP‐6, while increase in ESI was observed for SPP‐4 above 200 MPa (P < 0.05). SPP‐2 emulsions showed sharp decrease in apparent viscosity with pressure increase, while pseudo plastic flow behaviour was not changed for all of emulsions. Sporamins A and B were well‐adsorbed in pressurised emulsion without displacement. These results suggest that HHP treatment could be used to modify the physicochemical and emulsifying properties of SPP.

Effect of heat treatments on the structure and emulsifying properties of protein isolates from cumin seeds (Cuminum cyminum)

“…The n value in emulsion stabilized by native protein decreased with protein concentration increasing, while it increased in the emulsion stabilized by heated CPI for all the thermal treatments tested (Table 3) . Guo and Mu (2011) found that the apparent viscosity of sweet potato emulsions decreased with an increasing protein concentration in the range from 0.1 to 2.0%, and similar results were reported with protein concentration ranging from 2.0 to 4.0% (Khan et al., 2013). Indeed, emulsions formed with higher protein concentrations are more stable and have higher interfacial protein concentrations, producing smaller emulsion droplet size, which could efficiently prevent flocculation between the droplets (Guo and Mu, 2011).…”

High Hydrostatic Pressure (HHP)-Induced Structural Modification of Patatin and Its Antioxidant Activities

“…The thermal denaturation and stability of NP and HHP-treated patatin were analyzed using a differential scanning calorimeter (Q200; TA Instruments, New Castle, DE, USA) [ 67 ]. NP and HHP-treated patatin were accurately weighed (≤1 mg each), followed by transfer to an aluminum pan with 10 μL of 0.05 M phosphate buffer (pH 7.0) and mixing to uniformity.…”

Effects of high hydrostatic pressure on secondary structure and emulsifying behavior of sweet potato protein

“…The emulsion produced with control (0.1 MPa) SPPs had a fairly homogenous structure, which was in accordance with the results obtained in our pervious study. [17,18,19] The emulsions produced with HHP-treated SPPs (pH 3, 6, and 9) showed no sign of obvious flocculation. However, the Downloaded by [University of Nebraska, Lincoln] at 09:07 12 April 2015 droplet sizes were observed smaller compared to control (0.1 MPa) SPP at pH 3 and pH 6; furthermore, the emulsion produced at pH 9 showed no differences in microphotography which also supports the droplet size distribution results for pH 9.…”

“…[14][15][16] In our previous work, we have evaluated the emulsifying properties of SPP and found that it has good emulsifying activity and stability; however, in the previous case, the emulsions were produced before the HHP treatment. [17,18] This study was amid to evaluate the emulsifying behavior of SPP after the HHP treatment with different pH media (pH 3, 6, and 9).…”