Acid‐induced aggregation and gelation of heat‐treated chia proteins

INGRASSIA, ROMINA; BOERIS, VALERIA; INGRASSIA, ROMINA; BOERIS, VALERIA; BUSTI, PABLO; SPELZINI, DARÍO; BUSTI, PABLO; SPELZINI, DARÍO; LÓPEZ, DÉBORA N.; WAGNER, JORGE; LÓPEZ, DÉBORA N.; WAGNER, JORGE

INTERNATIONAL JOURNAL OF FOOD SCIENCE AND TECHNOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Año: 2020 p. 1641 - 1648

0950-5423

This work studied for thefirst time the acid‐induced aggregation and gelation of heat‐treated chiaprotein isolates obtained by extraction at pH 10 or 12 (CPI10 and CPI12,respectively). The aggregation state of proteins was modified duringacidification. The size of the aggregates was reduced for both samples when thepH decreased but below pH 4.5 further protein aggregation took place for CPI12.Gelation of CPI12 was completed after about 30 minutes of acidification withglucone‐δ‐lactone. By contrast, this period was not enough to reach a constant valuein G´ for CPI10. When gelation was ensured, confocal laser scanning micrographsfrom those gels revealed a coarse and irregular structure with large pores(median size of diameters: 30 μm). Instead, micrographs from CPI12 cold gels showed a more regular andinterconnected network, with smaller pores (median size of diameters: 9 μm). Thesedifferences are consistent with a higher elastic behaviour (G?max=13.6 ± 0.1Pa).