Effect Of Sucrose Esters On Fat Crystallization,interfacial Properites And Whipped Cream Quality

Whipped cream can be described as a metastable semi-solid aerated food after the whipping of oil-in-water emulsion composed of fats,sugars,proteins,emulsifiers and hydrocolloid,etc.Previous studies have found that emulsifiers affect the quality of whipped cream mainly by governing fat crystallization and interfacial properties.Sucrose esters are commonly used emulsifiers in food.Sucrose esters with different fatty acids moieties and esterification degrees played important roles in fat crystallization and interfacial properties.However,there were relatively few studies on the use of sucrose esters in whipped cream systems.The influence mechanisms of sucrose esters on the quality of whipped cream by affecting fat crystallization and interfacial properties are still unclear.Therefore,in this study,from the perspective of fat crystallization and interfacial properties,the effect and mechanism of sucrose esters with different fatty acid moieties and esterification degrees on the quality of whipped cream was systematically studied.Firstly,the effect of hydrophobic sucrose ester S370 concentration on fat crystallization and whipped cream quality were studied.The addition of S370 can be used as a nucleation template to induce nucleation and reduce the crystal size of fat.The addition of S370 resulted in lower degree of fat coalescence,lower interfacial protein concentration,longer optimum whipping time and higher overrun of whipped cream.When S370 concentration was lower than 0.05 wt%,large-size crystals and inhomogeneous partial coalescence network led to poor stability of whipped cream.When S370 concentration was higher than 0.05 wt%,the thinner interfacial protein layer and weaker fat coalescence network structure resulted in lower firmness and poor stability of whipped cream.When S370 concentration was 0.05 wt%,homogeneous partial coalescence network and denser interfacial layer resulted in better stability of whipped cream.Further,the effect and mechanism of five hydrophobic sucrose esters with different fatty acid moieties and esterification degrees on fat crystallization,interfacial properties and whipped cream quality were compared and analyzed.Low-melting-point short chain sucrose ester L195 and unsaturated sucrose ester O170 as interfering substances resulted in large-size crystals inside the fat globules.High-melting-point long chain sucrose esters S170,S370 and S570 could function as nucleation templates to reduce the size of fat crystals.L195 and O170 remained liquid at the oil-water interface,causing lower interfacial elastic modulus(E′).While S170,S370 and S570 can induce interfacial crystallization and enhance E′.Whipped cream with L195 and O170 presented poorer stabilities,caused by higher partial coalescence,larger-size crystals and inhomogeneous network.Smaller-size crystals and lower partial coalescence was detected in whipped creams with S170,S370 and S570,which displayed homogeneous network structure and better stabilities.Next,the effects of different concentrations of the hydrophilic sucrose ester S1570 on the interfacial properties and quality of whipped cream were investigated.When the concentration of S1570 was lower than 0.10 wt%,the coexistence of sucrose ester and sodium caseinate at the oil-water interface retarded the partial coalescence rate,prolonged the whipping time and increased the overrun,which caused the loose partial coalescence network and poorer stabilities of whipped cream.When the concentration of S1570 was 0.30-0.50 wt%,the interfacial protein was displaced by S1570,accelerated the shear-induced fat partial coalescence during whipping but inhibited the surface-mediated partial coalescence,which caused loose partial coalescence network around air bubbles and poorer stabilities of whipped cream.Finally,the effects of concentrations of three hydrophilic sucrose ester with different fatty acid moieties and esterification degrees on the rheological properties of the oil-water interface and quality of whipped cream were compared and analyzed.Low-concentration hydrophilic sucrose esters can coexist with sodium caseinate(SC)at the oil-water interface to improve the viscoelasticity of the interfacial layer.As the concentration of sucrose esters increased,the interfacial protein network structure was destroyed due to competitive adsorption,resulting in a decrease in the interfacial viscoelasticity.When S1170 with more polyesters and sodium caseinate were competitively adsorbed at the interface,stronger intermolecular interactions caused higher interfacial viscoelasticity.When P1570 with more short-chain monoesters and sodium caseinate were competitively adsorbed at the interface,weaker intermolecular interactions led to lower interfacial viscoelasticity.When the concentration of sucrose esters was 0.10 wt%,all three sucrose esters could coexist with sodium caseinate at the interface of emulsion droplets surface,and there was no significant difference among the partial coalescence degree,overrun and stability of whipped cream(p>0.05).When the sucrose ester concentration was 0.50 wt%,the interfacial layer viscoelasticity of P1570-SC was the lowest,and the stability of whipped cream was the worst.The interfacial layer viscoelasticity of S1170-SC was higher,and the stability of whipped cream was better.