Anais do Simpósio Latino Americano de Ciências de Alimentos
Anais do 14 SLACA - Simpósio Latino Americano de Ciência de Alimentos

Artisanal cheese is commonly produced on small and familiar farms and is characterized by end-to-end manufacturing. Whey is a by-product of cheese production and, on smallholdings, it is generally used for animal feed or improperly disposed due to the lack of technological knowledge for the development of whey-based products. Moreover, the absence of data on non-bovine whey is an additional barrier to the exploration of this protein source. To partially fill this gap, we studied the thermal death of microbial load in goat’s milk whey (GMW), aiming to determine the kinetic parameters (D-values and z) for batch processes at 62 – 85ºC. Unprocessed GCW had 8.2±0.1 log CFU.ml-1, pH 5.65±0.01 and acidity of 15.3±0.3g lactic acid.100 mL-1. Come-up time for processes at 62-71ºC was able to inactivate 0.96-1.81 log CFU.ml-1, indicating that there was a fraction of microorganisms very sensitive to heating. On the other hand, almost all the microbial load was inactivated (7.81-8.17 log CFU.ml-1) at come-up time in processes carried out at temperatures > 80ºC (residual count ranged from 0 to 2 colonies.mL-1, regardless of the time of the processes). A linear model of kinetic inactivation (Bigelow’s model) was fitted to the data of the inactivation curves at 62-75ºC (0.78> R2> 0.99) and the D-values were determined at 62 (64.4±0.8 min), 65 (33.9±0.9 min), 68 (11.4±1.0 min), 71 (5.4±1.0 min) and 75ºC (1.7±0.9 min). These values were used to determine the z-value of the microorganisms in GMW (8.1ºC, R2=0.99). Visual evaluation of the samples showed that only processes at 85ºC / ≥5 min caused intense protein destabilization. These data can be used to design GMW thermal processes, aiming to extend the shelf life of the product shelf-life and, consequently, allowing its use as ingredient in dairy and non-dairy products.