Peanut Shell Valorization: Effects of Particle Size on Techno-Functional Attributes, Mineral Profile, Starch Digestibility, and Bioactive Properties of Cookies
Ulgen Ilknur Konak Alkis, Fundagul Erem, Nazli Sahin
article (Uluslararası, Hakemli) | Yazar(lar): Ulgen Ilknur Konak Alkis, Fundagul Erem, Nazli Sahin | Yıl: 2026 | Dergi/Kurum: JOURNAL OF FOOD SCIENCE | İndeks: WOS.SCI | DOI: 10.1111/1750-3841.71145 — Özet: Peanuts are among the most widely produced nuts globally, generating greater quantities of shell residues than ot
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 & micro;m) 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 & micro;m, 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.