Final answer:
The first commercial pasteurization process was applied to wine, discovered by Louis Pasteur in 1856. Pasteurization of milk, which began in the 1860s, significantly improved public health by making milk safer to drink.
Step-by-step explanation:
The first product to be commercially treated by pasteurization was wine. Louis Pasteur discovered microbial fermentation in 1856 while studying causes of spoilage in wine and beer. However, it was the pasteurization of milk, which began in the 1860s following Pasteur's discoveries, that had a significant impact on public health by heating milk to destroy pathogens and making it safer to drink.
The first product to be commercially treated by pasteurization was milk. Louis Pasteur, a French scientist, developed the pasteurization process in the 1860s as a way to safely consume milk by heating it to destroy pathogens.