When evaluating quality, focus on the moisture content, which should typically range between 15% and 25% to ensure shelf stability without being overly tough. Check for uniformity in size and color (deep purple to black), as this indicates consistent processing. Ensure the product is free from foreign materials like stems, leaves, or sugar clumping. For premium markets, prioritize Wild Blueberries (Vaccinium angustifolium) over cultivated ones, as they offer a higher antioxidant concentration and more intense flavor profile.