Oak barrels are used throughout the world for whisky maturation.  There are two primary sources of American oak and French oak, both work well for maturation but impart different finishes.

Origins & Grain

• French Oak (Quercus robur): Tight grain, high tannins. Slower extraction = layered complexity.
• American Oak (Quercus alba): Wide grain, rich in lactones. Faster extraction = bold, sweet flavours. Vanillin and iso-vanillin

Flavour & Aroma

French Oak drier and finer finishes, common in Australian whisky. American Oak brings dessert-like richness think bourbon vanillas.

STR Cask Treatment

STR = Shaved, Toasted, Re-charred
This method refreshes wine casks for whisky, enhancing flavour extraction.

• French Oak STR: Boosts spice, dried fruit, and depth.
• American Oak STR: Amplifies vanilla, caramel, and sweetness.

Morris source French Oak and American Oak from ex-red wine barrels within the Barossa and Coonawarra region, both play distinct roles in shaping flavour, texture, and complexity.

Oak Origins and Grain Structure

French Oak (Quercus robur)

• Origin: Harvested from forests across France, including Limousin and Allier.
• Grain: Tighter grain structure, which slows the release of flavour compounds.
• Common Use: Often used in premium red wine barrels, making them ideal for reuse in whisky maturation.

American Oak (Quercus alba)

• Origin: Grown primarily in the United States, especially Missouri and Kentucky.
• Grain: Wider grain allows for faster extraction of flavour compounds.
• Common Use: Widely used in bourbon production and increasingly in Australian whisky via wine cask repurposing.

Australian Red Wine Influence

Morris Whisky employ a method to remove the red wine taint from the barrels and re-purpose them into excellent whisky barrels. Applying this method after toasting allows the whisky to perfectly mature.

Flavour Profiles in Maturation

French Oak

• Tannins: Higher tannin content adds structure and grip.
• Flavours: Spice (clove, cinnamon), dried herbs, and subtle toast.
• Mouthfeel: Often drier and more complex.
• Ideal For: Longer maturation, bold wine cask finishes, and whiskies with depth.

American Oak

• Tannins: Lower tannin levels, softer texture.
• Flavours: Vanilla, coconut, caramel, and sweet spice.
• Mouthfeel: Creamier and rounder.
• Ideal For: Quicker maturation, sweeter profiles, and approachable expressions.

French Oak and American Oak each bring something special to the table. In the hands of Morris of Rutherglen, especially when paired with STR and our own coopers, these casks form the backbone of our superb spirits.