What is the primary benefit of using stainless steel or glass for inert vessels?

Using stainless steel or glass for inert vessels provides the essential benefit of not reacting with the spirit. This characteristic ensures that the purity of the spirit is maintained during storage or fermentation processes. Reaction with the vessel material can lead to unintended flavor changes or chemical interactions that would alter the spirit's intended profile, thereby affecting its quality and taste.

While aesthetics and ease of cleaning can be important factors in vessel selection, they do not contribute to the preservation of the spirit’s integrity like the inert nature of stainless steel and glass. Additionally, these materials are designed to avoid imparting any flavors to the spirit, which is crucial for maintaining the authenticity of premium spirits. Thus, the inertness of materials like stainless steel and glass is critical in the production and storage of spirits, making it the primary benefit in their use.