Title : Effect of oleaster (Elaeagnus angustifolia) flour on the properties of gluten-free buckwheat pasta: Enhancing functional, nutritional, and quality attributes
Abstract:
The increasing demand for gluten-free products has led to the development of alternative formulations, especially for widely consumed foods like pasta. This study focuses on producing gluten-free pasta using different combinations of buckwheat flour and 20% flour from various parts of oleaster fruit (Elaeagnus angustifolia), including shell, seed, and pulp. The research examines the chemical, nutritional, and quality properties of the resulting pasta. The moisture content of oleaster-derived flours was higher than that of wheat and buckwheat flours, with oleaster pulp containing the highest ash content (2.36%). Protein content varied between 8.14% and 13.07%, with the highest value found in seed flour. pH values of gluten-free pasta doughs containing oleaster flours were lower than those of control wheat and buckwheat pasta doughs. The moisture content of gluten-free pastas with different oleaster flours showed no statistically significant difference (p>0.05). Among the pastas, CKM pasta (containing seed flour) had the highest protein content (18.36%), whereas control buckwheat pasta (KM) and KKM pasta (containing 20% shell flour) had the lowest. The highest fat content (5.40%) was found in PKM pasta, which contained 20% oleaster pulp flour.
Cooking properties varied among samples. The control wheat pasta exhibited the highest weight and volume increase (186.34% and 276.60%, respectively), whereas among oleaster-containing pastas, PKM pasta (containing pulp flour) showed the highest values (172.17% and 245%, respectively). Water absorption was highest in KKM pasta (containing shell flour) at 11.14%. Cooking time was shortest in wheat pasta and PKM pasta (both at 11 minutes).
Textural analysis revealed that KKM pasta, containing shell flour, exhibited the highest hardness and brittleness. Pasta thickness ranged from 1.17 mm to 2.24 mm, with the thickest being PKCM pasta, which contained a combination of core-shell and pulp flour. In terms of bioactive properties, total phenolic content, antioxidant capacity, and flavonoid content varied significantly depending on the oleaster flour used (p<0.05). The highest total phenolic content was found in KCKM pasta (56.61 mg/100g), which contained equal amounts of shell and kernel flour. The highest antioxidant activity (81.89%) and flavonoid content (11.01 mg/g) were observed in PKM and KKM pasta, respectively. Color measurements showed differences based on the type of oleaster flour used. The highest L* value (66.35) was found in KKM and PKM gluten-free pasta, the highest a* value (6.00) in CKM pasta, and the highest b* value (29.72) in wheat pasta. Overall, oleaster pulp and seed flours demonstrated higher nutritional quality than other parts, with oleaster pulp exhibiting technological properties comparable to wheat pasta. The study highlights the potential of using oleaster fruit parts, typically consumed as dried fruit, as valuable ingredients in gluten-free pasta production.
