Italian and Italian-style hard cooked cheeses: Predictive formulas for Parmigiano-Reggiano 24-h cheese yield

Predicting the 24-h Parmigiano-Reggiano (PR-RE) cheese yield (CY) is relevant for controlling the efficacy of cheese-making processes, yet the existing formulas are old and need to be re-evaluated. To this aim, 119 cheese-making trials were carried out in 20 different dairies to calculate the 24-h actual CY. From a subset of 89 trials, 35 formulas for 24-h PR-RE CY were developed by applying a multiple regression analysis using up to 14 milk parameters as predictors. The formulas were validated on a second data subset (30 trials). The predictive ability was not significantly improved by increasing the predictors when a formula based on milk fat and casein contents was considered (R2 = 0.872). The formula predicted 24-h CY more effectively than the existing formulas for Italian hard cheeses. Using a database obtained from a single dairy, the predictive ability of the resulting formula was further improved.