Study of the Grape Cryo-Maceration Process at Different Temperatures.

This research aimed to determine the effects of cryo-maceration at different temperatures on polyphenol content during the winemaking process of Chardonnay wine. Samples of Chardonnay grapes were subjected to rapid cooling processes by direct injection of liquid CO₂ to obtain final temperatures of 10.0, 8.0, 6.0 and 4.0 °C and yield different batches of grape mash. Subsequently, each batch underwent the winemaking process to produce four different wines. The wines obtained were characterized by chemical analyses. We observed higher extraction of polyphenolic compounds with low-temperature cold maceration, particularly when the temperature was reduced from 10.0 to 6.0 °C. Conversely, when the temperature was reduced below 6.0 °C, the increase in polyphenol content in wine was negligible, whereas CO₂ consumption increased. Furthermore, a numerical simulation was performed to determine the pipe length, L₀, after which the temperature was constant. This condition is very important because it guarantees that after the length L₀, the thermodynamic exchange between liquid CO₂ and is complete, eliminating the possibility of liquid CO₂ pockets in the cyclone.