Lemon and caper butter, flavouring profile

Lemon and caper butter, flavouring profile

This sauce is sharper and saltier than it looks, and a wine short on acidity turns soft and dull the moment it meets it.

The compounds that matter. Citric acid from the lemon, which sets a floor of sharpness the wine must match or clear. Capers, which bring brine and a faint mustard bite from the same family of compounds that makes mustard hot. Butter, whose fat coats the palate and needs acid to lift it.

What it demands of a wine. High acidity above all, and a citrus or green herb note to meet the lemon and the capers. No oak: the sauce usually goes on white fish, and fish and oak together taste metallic. Tannin has no place here, and neither does a soft, perfumed white.

Seek. Loire Sauvignon Blanc, from Sancerre or Touraine, whose gooseberry and green herb sit right on the capers. Aligoté from Burgundy, lean and lemony. Assyrtiko from Santorini, for salt and grip. Unoaked Chablis, chalky and taut. Loureiro from Vinho Verde, light and floral with a lemon edge.

Avoid

Oaked Chardonnay and any oaked white, since the barrel turns metallic beside fish and blurs the lemon. Red wine of any kind. Soft, aromatic whites low in acid, such as Viognier, which taste flabby against the sauce.

Three to reach for. Sauvignon Blanc, Sancerre, France. Dry Semillon, Hunter Valley, Australia. Verdejo, Rueda, Spain.