Role of the bolus degree of structure on the protein digestibility during in vitro digestion of a pea protein‐fortified sponge cake chewed by elderly

• Published in: Journal of texture studies 2020-02, Vol.51 (1), p.134-143
• Main Authors: Assad‐Bustillos, Melissa, Palier, Juliette, Rabesona, Hanitra, Choiset, Yvan, Della Valle, Guy, Feron, Gilles
• Format: Article
• Language: English
• Subjects: bolus viscosity; Chemical Sciences; digestibility; Food and Nutrition; Geriatry and gerontology; Human health and pathology; INFOGEST; Life Sciences; or physical chemistry; oral processing; proteolysis; Theoretical and
• ISSN: 0022-4901; 1745-4603
• DOI: 10.1111/jtxs.12486

This study investigated the digestibility of proteins in a pea protein‐fortified sponge cake, as well as the impact of the degree of structure of the bolus produced by elderly subjects on the digestibility of proteins by combining ex vivo and in vitro approaches via the standardized protocol INFOGEST. The sponge cakes were consumed by a group of 20 elderly subjects with contrasting physiology, their boli were recovered just before swallowing, and their apparent viscosity was measured to delineate the bolus degree of structure. According to this criterion, two pools were formed with boli from subjects selected at the extremes: low viscosity and high viscosity, with apparent viscosity values (at 120 s−1) of 124 ± 18 and 208 ± 19 Pa s, respectively. The sponge cakes and the two pools underwent in vitro digestion. Protein hydrolysis kinetics was followed by measuring the released primary amino groups (NH2) and by sodium‐dodecyl‐sulfate polyacrylamide gel electrophoresis at different time points. For all samples, the representative bands of pea proteins disappear gradually during digestion, accompanied by the appearance of bands indicating the presence of proteins with MW