Riesling — Mosel Style Winemaking Protocol

The style is grown on steep slate slopes whose stored heat and sharp drainage let Riesling ripen slowly in a cool climate while holding its acidity. Low vigour and long hang time build flavour and the terpene pool; a canopy managed with sun exposure in mind also governs how much TDN precursor accumulates.

For the higher Prädikat wines, noble Botrytis is welcomed and selectively picked; for clean, fresh styles it is sorted out. Keep vine nitrogen moderate — enough for a complete, if slow, ferment.

Pick by must weight (measured in Oechsle) to target the Prädikat: Kabinett is the lightest, then Spätlese, then Auslese and the botrytis-concentrated Beeren- and Trockenbeerenauslese. Retaining acidity is as important as sugar — the pick balances rising sugar against falling acid.

Higher Prädikat wines are hand-harvested with selective passes, picking botrytised or shrivelled berries separately for concentration.

Handle cool and protectively. Whole-bunch pressing is typical, giving a delicate, low-phenolic juice; work under SO₂ and inert gas to protect the florals and keep the wine pale.

Botrytis fruit is pressed with particular care, as it is fragile and oxidation-prone.

Settle cool to a moderate clarity — not ultra-clean, since Riesling ferments are slow and some solids help the yeast finish (or, for sweet styles, ferment steadily to the arrest point).

Keep everything cold and protected through settling.

Usually minimal — whole-bunch pressing already gives clean juice, and a pectolytic enzyme is optional for settling only.

Glycosidase enzymes that free bound terpenes are generally avoided: the style relies on the grape's natural terpene balance developing slowly in bottle, not on an up-front aromatic release.

Choose cool-tolerant, low-temperature strains that respect the aromatics; indigenous ferments are common for complexity. For sweet styles, strains that ferment slowly and can be halted — or that stop naturally at lower alcohol — are useful.

Whatever the choice, the aim is a clean, slow ferment that neither strips terpenes nor pushes higher alcohols.

Ferment cool, roughly 12–18 °C, and let it run for weeks to months. The slow, cold ferment preserves the delicate florals and the wine's freshness.

Patience here is the method — rushing a Riesling ferment warm costs exactly the perfume and tension the style is known for.

The signature choice is how much residual sugar to leave. Either arrest the ferment at the target sugar/alcohol balance — chilling hard, adding SO₂ and racking or sterile-filtering the wine off its yeast — or use a low-alcohol-tolerant yeast that stops of its own accord.

The residual sugar is set against the very high acidity: a Kabinett with 30–45 g/L sugar can still taste vibrant, not sweet, because the acid balances it. This tension is the heart of the Mosel style.

Malolactic is deliberately avoided to keep the sharp malic acidity that defines the wine and drives its ageability.

Maintain SO₂ and keep the wine cool to prevent malolactic starting on its own.

Handle protectively to preserve the florals and the pale colour — inert cover, minimal oxygen — though a little reductive, slaty character is often welcomed rather than feared.

SO₂ matters especially for the sweet styles: residual sugar is a refermentation and microbial risk, so target adequate molecular SO₂ (the low pH helps achieve it) and keep it maintained.

Stabilise protein with a heat-test-guided bentonite and tartrate by cold, and — critically for any wine with residual sugar — sterile-filter before bottling to prevent refermentation in bottle.

There is no oak: the wine is raised in stainless steel or in large, old, neutral Fuder casks that give slow micro-oxygenation without any wood flavour. New oak would trample the delicacy.

Bottle protectively with low oxygen pickup, under screwcap or cork, to keep the wine fresh and to curate the slow development of the petrol (TDN) note.

Good Mosel Riesling ages for years to decades, the primary lime and floral notes deepening toward honey, dried fruit and that characteristic mineral, petrol-tinged maturity.