Complex coacervation and freeze‐drying using whey protein concentrate, soy protein isolate and arabic gum to improve the oxidative stability of chia oil

BORDÓN, MARÍA GABRIELA; BARRERA, GABRIELA NOEL; GONZÁLEZ, AGUSTÍN; RIBOTTA, PABLO DANIEL; MARTÍNEZ, MARCELA LILIAN

JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE

JOHN WILEY & SONS LTD

Año: 2023 vol. 103 p. 3322 - 3333

0022-5142

BACKGROUNDChia oil (CO) is popular for being the richest vegetable source of α-linolenic acid (60-66 %). However, this content of polyunsaturated fatty acids limits the incorporation of bulk CO in food products due to its high probability of oxidation. This justifies the study of alternative wall materials for microencapsulation. No reports regarding the use of dairy protein/vegetable protein/polysaccharide blends as wall material for the microencapsulation of CO were published. Therefore, this work analyzed the behavior of a whey protein concentrate (WPC)/soy protein isolate (SPI)/arabic gum (AG) blend as wall material. The complex coacervation (CC) process was studied: pH (4.0); total solid content (30% w/v); WPC/SPI/AG ratio (8/1/1 w/w/w); stirring speed (600 rpm) and time (30 min); room temperature.RESULTSThe oxidative stability index (OSI) of CO (3.25±0.16 h) was significantly increased after microencapsulation (around 4 times higher). Besides the well-known matrix-forming ability of AG, WPC helped increase the OSI of microencapsulated oils. Meanwhile, SPI contributed to the increase of the encapsulation efficiency due to its high viscosity. Enhanced properties were observed with CC: encapsulation efficiency (up to 79.88%), OSIs (from 11.25 to 12.52 h) and thermal stability of microcapsules given by the denaturation peak temperatures of WPC (from 77.12 to 86.00 °C). No significant differences were observed in the fatty acid composition of bulk and microencapsulated oils.CONCLUSIONMicrocapsules developed from complex coacervates based on the ternary blend represent promising omega-3-rich carriers for being incorporated into functional foods.