"Enhancement of flaxseed oil quality and yield using freeze-thaw pretreatment optimization: A novel approach"

The impact of freezing-thawing (FT) pretreatment on flaxseed oil yield and quality was evaluated by pre-screening process parameters using a Taguchi design and further optimizing them through response surface methodology. The study examined freezing time (6-48 h), thawing time (6-24 h), and the number of cycles (1-5) on oil yield, thermal diffusivity, phenolic content, and antioxidants. The optimal conditions 6 h freezing, 6 h thawing, and 4 cycles resulted in a 50 % increase in oil yield and a 20 to 27 % improvement in antioxidants. Microstructural analysis showed surface disruptions at the cellular level, facilitating enhanced oil extraction. Additionally, the FT pretreatment increased thermal conductivity and diffusivity due to cracks and voids in the treated seeds. Furthermore, FT pretreatment did not affect the fatty acid profile or key physicochemical parameters (acid value 1.47 mg/KOH, peroxide value 2 meqO₂/kg, p-anisidine value 0.5 AnV), maintaining the oil's stability and quality. Therefore, FT pretreatment is an effective technique to enhance the oil yield and quality, providing a promising alternative to meet the growing global demand for edible oil.