Fish smoking in the French tradition encompasses two distinct techniques: fumage à froid (cold smoking, 15-25°C) and fumage à chaud (hot smoking, 60-90°C), each producing fundamentally different products. Cold smoking preserves and flavours without cooking — the fish remains essentially raw but profoundly transformed; hot smoking cooks and flavours simultaneously, producing flaky, fully cooked flesh. Both techniques begin with curing: the fish is either dry-cured (packed in a mixture of salt, sugar, and aromatics for 12-24 hours) or brined (soaked in an 8-10% salt solution for 4-8 hours depending on thickness). The cure draws moisture from the flesh via osmosis, firms the protein structure, and creates the sticky, glossy surface called the pellicle — essential for smoke adhesion. After curing, the fish is rinsed and air-dried uncovered in the refrigerator for 12-24 hours until the pellicle forms (the surface feels tacky but not wet). COLD SMOKING: hardwood sawdust (traditionally beech, oak, or alder) smoulders in a chamber separate from the fish, and the smoke is channelled at 15-25°C for 8-24 hours. Salmon is the classic subject: saumon fumé requires 12-18 hours of cold smoke after a 24-hour dry cure (3:1 salt to sugar ratio). The result is silky, translucent, and complex. HOT SMOKING: the fish sits directly above smouldering wood chips in a closed chamber at 60-90°C for 1-4 hours. Trout is the classic subject: truite fumée requires 2-3 hours at 80°C. The flesh is fully cooked, flaky, and intensely smoky. The wood choice matters enormously: beech gives a clean, mild smoke; oak is deeper and more assertive; alder is sweet and light; apple and cherry add fruity notes.
Curing before smoking is non-negotiable — it firms the flesh, develops the pellicle, and enables smoke adhesion The pellicle must be dry and tacky — wet fish repels smoke, producing an acrid, surface-only flavour Cold smoke: 15-25°C — above 25°C, bacterial growth accelerates dangerously Hot smoke: 60-90°C — below 60°C, the fish is in the danger zone; above 90°C, it dries out Wood choice defines the character — match the wood to the fish intensity
Add juniper berries, black pepper, and dill fronds to the dry cure for a Scandinavian-French hybrid that is extraordinary A light brush of maple syrup on the pellicle before hot smoking creates a lacquered, caramelised surface Cold-smoked salmon sliced paper-thin on the bias with a long, flexible knife should be translucent — thick slicing wastes the texture that smoking creates
Skipping the pellicle formation — smoke slides off wet fish and produces a bitter, harsh flavour Cold smoking above 25°C — the fish enters the bacterial danger zone (25-60°C) and becomes unsafe Over-curing with too much salt — the fish becomes unbearably salty and the texture turns leathery Using resinous softwoods (pine, spruce, cedar) — they produce acrid, creosote-laden smoke that is toxic Rushing the process — good smoking cannot be accelerated without sacrificing quality
Larousse Gastronomique; Charcuterie and French Pork Cookery (Jane Grigson)