Final answer:
Before pasteurization, foods and beverages could carry pathogens that are now typically killed by the pasteurization process, improving safety. Products like milk and cheese were particularly susceptible to contamination. Pasteurization preserves the sensory qualities of foods while ensuring they are safe for consumption.
Step-by-step explanation:
Pasteurization, developed by Louis Pasteur in the 1860s, is a process of heating foods and beverages to kill pathogens and reduce the number of spoilage-causing microbes without rendering the product sterile. Before pasteurization, foods and beverages like milk, cheese, wine, and beer could contain harmful microorganisms such as Campylobacter jejuni, Escherichia coli, and Salmonella spp., which pose a risk to human health. Milk, in particular, could transmit deadly diseases due to its susceptibility to contamination by a variety of pathogens.
With pasteurization, the safety of products like milk is greatly improved, as this process effectively kills many microorganisms responsible for diseases and food spoilage. In modern times, UHT pasteurization has taken this process further, allowing milk to be heated at higher temperatures and stored for extended periods without refrigeration. The introduction of pasteurized products has thus transformed the food and drink industry, providing safer options for consumers while preserving the sensory qualities of the products.