Effect of masticatory behavior on the characteristics of biscuit bolus with different amounts of chia seed powder without compromising taste

This study investigated the impact of masticatory behavior, including variations in chewing duration (D) and chewing frequency (F), on the bolus characteristics of biscuits with different chia seed powder (CSP) additions. Five distinct biscuits were prepared with varying amounts of CSP (0%, 5%, 10%, 15%, and 20%, w/w) and their physicochemical indexes and sensory properties were conducted. Subsequently, six types of bolus were obtained under different conditions of chewing duration (15, 30, or 45s) and chewing frequencies (70 or 90 times per minute). The moisture content, texture properties, and in vitro starch digestion of bolus were also determined. The findings indicated a significant decrease in the spread ratio, with a reduction of approximately 25% in biscuits enriched with 20% (w/w) CSP compared to the control (0%). And the 15% added CSP biscuits had the highest overall acceptance rating. After chewing, the particle size decreased significantly (p < 0.05), with increased surface inhomogeneity and a decline in rapidly digestible starch (RDS) levels. The moisture content, salivary uptake, and resistant starch (RS) of bolus chewed for a long duration (D45) were at least 1.3 times higher than those chewed for a short duration (D15). Nevertheless, the salivary flow rate and RDS were found to be significantly lower. Changes in chewing frequency for the bolus with CSP did not significantly alter the bolus texture and image texture properties. However, the discomfort associated with high-frequency reduced the saliva flow rate. This study discusses how CSP addition and masticatory behavior affect the characteristics of CSP biscuit bolus, providing insights for innovative chia seed nutritious food research and understanding consumer masticatory behavior.