Croser is the traditional-method sparkling wine of Petaluma, founded by Brian Croser, and is grown in the cool, elevated Adelaide Hills of South Australia, a region Croser helped pioneer for premium sparkling. Chardonnay and Pinot Noir are drawn from high-altitude sites where grey-brown loam and clay soils over rock, combined with cool nights and a long, mild ripening season, retain the fine acidity essential to sparkling base wine. As a Non-Vintage brut, the wine is assembled for continuity of house style rather than from a single season, blending across parcels and years. Cool-climate site selection and early picking at modest ripeness give the delicate, high-acid fruit the style demands.

Chardonnay and Pinot Noir are harvested early and whole-bunch pressed to preserve freshness, with the base wines fermented in stainless steel and blended for the house brut style. The cuvee then undergoes a second fermentation in bottle following the methode traditionnelle and is aged on its lees to build fine, persistent bubbles and subtle bready, biscuity complexity. After riddling and disgorgement it is finished to a brut dosage. The wine shows citrus and white-stone fruit, a creamy mousse and a crisp, cool-climate finish. Exact lees-ageing duration and dosage for the current disgorgement were not individually confirmed and are flagged for verification.