ABSTRACT Peanuts are among the most widely produced nuts globally, generating greater quantities of shell residues than other nut by‐products, thereby representing a highly abundant source of lignocellulosic fiber and phenolic compounds. This study examined the effect of peanut shell ground to different sizes (212, 500, and 800 µm) on the physical, chemical, techno‐functional, and textural properties of cookies. As the particle size decreased, the dough's hardness increased, while its stickiness and strength decreased ( p < 0.05). Adding peanut shell to cookies resulted in approximately a 100‐fold increase in crude fiber content, a 1.8‐fold increase in total phenolic content, and a 2.4‐fold increase in antioxidant activity compared to the control sample ( p < 0.05). Moreover, as the particle size of the peanut shell decreased from 800 to 212 µm, starch digestibility declined, and the mineral content increased in the cookies ( p < 0.05). Incorporating peanut shell powder into cookies reduced their thickness by 8%–15% but increased the spread ratio by 18%–33% compared to the control cookies ( p < 0.05). The cookies' hardness and fracturability decreased by about 27%–47% and 1%–5%, respectively, as the particle size of the peanut shell powder increased ( p < 0.05). These findings suggest that peanut shell could serve as an important source of fiber and phenolic compounds for functional cookie production. Practical Applications Peanut shells, often discarded as processing waste, can be transformed into a valuable ingredient for healthier cookies. Adding peanut shell powder significantly increases fiber, antioxidants, and minerals while reducing starch digestibility. Using peanut shells in bakery products not only supports sustainable waste utilization but also offers an affordable way to create functional foods with added health benefits, an opportunity for both industry innovation and improved public nutrition. The significant increase in dietary fiber and antioxidant activity suggests that its incorporation could support clean‐label product development and align with consumer demand for health‐oriented food products.
Alkış et al. (Mon,) studied this question.