Tangy and lactic

Lactic acid

Every cheese begins with bacteria turning lactose into lactic acid. In lactic cheeses this acid does most of the work of setting the curd, and the finished cheese keeps much of it, giving a fresh, citrus-like sharpness. In rennet cheeses that are aged, other flavours slowly take over as the acid is used up or neutralised, especially near the surface of bloomy and washed rinds. So a clear tang is usually a mark of youth, and it softens as a cheese ripens.

Tangy cheeses of the world

France's young goat cheeses, Greek feta and Bulgarian sirene, and the crumbly British cheeses, Caerphilly, Wensleydale and Lancashire, all have a clear acidity. Quark and tvorog are tangy in the same way as yoghurt. Kalimpong cheese is mild and slightly tangy when young. Ethiopia's ayib, made from soured milk after the butter has been churned, is gently sour and is served beside stews spiced with berbere, where it cools the heat.

In cooking

Tangy cheeses balance richness and sweetness. Crumbled feta lifts lamb and roasted vegetables, goat cheese sets off sweet beetroot, and in Yorkshire, Wensleydale is eaten with fruit cake, especially at Christmas. Quark and tvorog give cheesecake and syrniki their gentle sourness. Indian cooks set paneer with lemon juice or vinegar and rinse it well, which leaves only a faint tang, but home-made paneer set with sour whey often keeps a little more.

Worth knowing

• Feta: Brined, salty and tangy
• Crottin de Chavignol: Lemony when young
• Caerphilly: Welsh crumbly cheese
• Wensleydale: Yorkshire cheese eaten with fruit cake
• Lancashire: Crumbly, buttery and tangy
• Quark: Spoonable lactic cheese
• Sirene: Bulgarian brined cheese

Sources and further reading

• Wensleydale cheese on Wikipedia
• Goat cheese, Wikipedia
• Lactic acid bacteria, Wikipedia