When evaluating vodka quality, focus on the raw material source (grain, potato, or grape) and the distillation purity. High-quality vodka typically undergoes multiple distillation cycles (e.g., 5x or 7x) to remove impurities. Ensure the supplier provides a Certificate of Analysis (COA) detailing the methanol and fusel oil levels, which must strictly adhere to international safety standards. Additionally, the filtration method—such as activated carbon, silver, or platinum filtration—significantly impacts the final mouthfeel and clarity.