Physical Properties and Oxidative Status of Concentrated-from-Fish Oils Microencapsulated in Trehalose/Sodium Caseinate Matrix

MARÍA SOLEDAD ALVAREZ CERIMEDO; ROBERTO J CANDAL; MARIA LIDIA HERRERA

FOOD AND BIOPROCESS TECHNOLOGY

SPRINGER

Lugar: Berlin; Año: 2014 vol. 7 p. 3536 - 3547

1935-5130

Foods supplemented with omega-3 fatty acids haveattracted much attention in the past decade. However, it isdifficult to protect polyunsaturated fatty acids from oxidation.Microencapsulation is a technological process used with theaim to protect oils against oxidation or chemical deterioration,to mask unpleasant flavors or retain aromas, and/or to powderpolyunsaturated fatty acids for food fortification purposes.The objective of this study was to analyze physical propertiesand oxidation status of microencapsulated concentratedfrom-fish oils. Powders were prepared from emulsionsformulated with 10 wt.% of concentrated-from-fish oilsas fat phase and 20 or 30 wt.% trehalose solution thatalso contained 0.5, 2.0, or 5.0 wt.% sodium caseinate asaqueous phase. Encapsulation efficiency was higher forpowders coming from 20 wt.% trehalose emulsions, andthe percentage of retention of core material increased withincreasing sodium caseinate concentration. The powderprepared from 20 wt.% trehalose and 5 wt.% sodiumcaseinate showed the highest retention of core material.This powder had lower water content and an amorphousmatrix. Matrix-assisted laser desorption ionization time-offlightmass spectrometry method, used for this new application,allowed proving that trehalose/sodium caseinatematrix was efficient for microencapsulation of polyunsaturatedoils and that concentrated-from-fish oils was protected fromoxidation in powder form. Spectra were very similar to theoriginal oil without any treatments. Most likely, the oxidationproducts found when core material was extracted were formedduring extraction steps.