Candles are an essential tool for sommeliers, enabling them to detect any sediments in a wine before pouring to ensure a pristine and enjoyable wine experience for their customers.

Sommeliers position the candle below the neck of the bottle and use the flame's glow to detect sediments and other residues before they reach the glass and risk tainting the wine.

Sediments are natural byproducts of fermentation and include tartrate crystals, or "wine diamonds," and lees, which are remnants of the yeasts that contribute to wine aging.

Though harmless, sediment in wine is unappealing. Home wine enthusiasts can use a phone's flashlight or any other light source to illuminate the bottle and reveal any sediments.

To avoid sediment in your glass, consider using a decanter with a filter, or store the bottle upright for a few days before serving, allowing sediment to settle at the bottom.