A fast and low-cost method for determining moisture content in frozen pre-fried potatoes

The pursuit of rapid, affordable, and energy-efficient analytical methods offers an opportunity to improve quality control in the food industry. In this context, this study developed and evaluated a gravimetric method for determining moisture content in frozen pre-fried potatoes, using a conventional air fryer as an alternative to an industrial convection oven procedure adapted from AOAC Official Method 984.25. Experimental optimization was performed using a Box–Behnken design comprising 15 experimental runs, combined with response surface methodology, considering sample mass (1–3 g), heating time (5–25 min), and temperature (100–140 °C). The optimized conditions were established at 1.0 g, 17.3 min, and 120 °C, yielding a mean moisture recovery of 101.74% (95% confidence interval: 99.92–103.56%), closely matching the model-predicted value of 102.35%. Comparison with the industrial procedure, standardized at 3 h and 105 °C, involved six independent samples analyzed in triplicate, with no statistically significant mean difference detected between the methods (p = 0.058). Relative standard deviations were 0.59% for repeatability and 1.57% for intermediate precision. The energy assessment, based on direct measurements, revealed an average electricity consumption of 0.122 kWh per cycle for the air fryer, compared with 0.867 kWh for the convection oven, corresponding to reductions of approximately 85.9% in electricity consumption and 90.4% in heating time. These findings highlight the potential of conventional, low-cost equipment as an alternative analytical solution, contributing to the development of faster, more accessible, and energy-efficient procedures for industrial quality control.