Abstract
Plant proteins are increasingly incorporated into food products to enhance their nutritional value. However, little is known about how this alters the textural perceptions of such products. This study investigated the substitution of up to 35% wheat flour with pea protein isolate (PPI) into pasta sheets to determine how this influenced texture. Furthermore, an in vivo human mastication test (n = 116 participants) was conducted to evaluate oral tactile perceptions (perceived firmness, stickiness, and brittleness) and chewing time associated with PPI-containing pasta. Cooked pasta hardness decreased from 145 to 96 N at 5% PPI substitution due to the disruption of gluten network but increased to 144 N at 15–25% PPI substitution, indicating a stronger protein network at higher PPI substitution levels. In vivo, pasta substituted with 25% PPI required a shorter chewing time and was perceived as less firm, less sticky, and more brittle than wheat flour-only pasta. Regardless of pasta samples, fast chewers (average chewing time ≤13 s) were better at recognizing differences in pasta firmness, while slow chewers (>13 s) were more sensitive to changes in stickiness and brittleness. The results obtained in this study could contribute to the design of protein-rich pasta tailored to populations with specific texture requirements (e.g., softer texture for the elderly).