Softening fat-free cream cheese by incorporating aggregates of pea protein hydrolysates

Abstract

Protein-based fat replacers are increasing in popularity due to their low-calorie nature and customers' preference on high protein foods. Nevertheless, their fabrication requires large energy input (75–95 °C, 20–40 min) which limits their food application. In the present study, pea protein isolates (PPI) were hydrolyzed by Alcalase, followed by mild heating (85 °C for 10 min) to form aggregates as fat replacer. Protein aggregates were added to skim milk at various concentrations (0.1, 0.3, 0.5%) to develop fat-free cream cheese. Chemical analysis found incorporation of pea protein hydrolysates aggregates (PPH) into fat-free cream cheese increased the moisture content from ∼63% to ∼70%. Rheological measurements showed the storage modulus (G’) was decreased from 36 kPa in the control cheese to 11 kPa and 25 kPa when at 0.3% PPH and PPI aggregates were added. Apparent viscosity (η) was decreased ∼78% and ∼36% with the addition of 0.3% PPH and PPI, respectively. Creep-recovery test showed under the same stress, the strain (%) and α, λ1, λ2 of cream cheese containing PPH had much larger value than those of PPI. The Confocal and Scanning Electron Microscopy showed a less continuous network with large aggregates in PPH contained cream cheese compared to those of PPI or negative control sample, possibly due to clustering of PPH or PPH-casein complex. The information provided from this study sheds light on the development of desirable plant protein-based fat replacer with higher energy efficiency for potential application of low-fat dairy foods.