فهرست نشریات علمی دسترسی آزاد ایران

This study investigated the relationship between the textural and color properties of macadamia nut and macadamia butter in different roasting conditions, including roasting temperature (RT), (100-140 °C) and roasting time (Rt), (5-15 min). The results indicated that increasing the RT resulted in a decrease in lightness (L*) and an increase in redness (a*) and yellowness (b*) for both the macadamia nut and butter. Moreover, an increase in RT led to a significant decrease in hardness and fracturability. The effect of Rt on textural properties was temperature-dependent: at lower RTs, increasing the Rt increased fracturability, while at higher RTs, it led to a decrease in fracturability. Principal component analysis (PCA) with two principal components (explaining 55.35 and 22.32% of the variance) revealed that both products’ a* and b* parameters were strongly positively correlated, while L* exhibited independent behavior. Regarding texture, the macadamia nut showed a positive correlation between hardness and fracturability, while the macadamia butter exhibited an inverse correlation between hardness and adhesiveness. In the process optimization phase, the optimal roasting conditions were determined to be 122 °C for 5 min for macadamia nut and 126 °C for 7 min for macadamia butter. These findings provide practical guidance for optimizing roasting conditions in the macadamia processing industry, enabling the production of nuts and butter with desirable sensory attributes and extended shelf-life.