Strained yoghurt, yoghurt cheese, labneh, or Greek yoghurt is yoghurt which has been strained in a cloth or paper bag or filter to remove the whey, giving a consistency between that of yoghurt and cheese, while preserving yoghurt's distinctive sour taste. Like many yoghurts, strained yoghurt is often made from milk which has been enriched by boiling off some of the water content, or by adding extra butterfat and powdered milk.
Yoghurt strained through muslin is a traditional food in the Levant, Eastern Mediterranean, Near East, and South Asia, where it is often used in cooking, as it is high enough in fat not to curdle at higher temperatures. It is used in both cooked and raw, savoury and sweet dishes. Due to the straining process to remove excess whey, even non-fat varieties are rich and creamy.
In Western Europe and the U.S., strained yoghurt has become increasingly popular because it is richer in texture than unstrained yoghurt, but low in fat. Since straining removes whey, strained yoghurt is higher in protein and lower in sugar and carbohydrates than unstrained yoghurt.
In fact, most of the recent growth in the $4.1 billion yoghurt industry has come from the strained yoghurt segment. In the West, the term "Greek yoghurt" has become synonymous with strained yoghurt due to successful marketing by the Greek Fage brand, though strained yoghurt is a staple in many countries besides Greece, and most yoghurt in Greece is not strained. "Greek-style" yoghurts are similar to Greek strained yoghurt, but may be thickened with thickening agents, or if made the traditional way, are based on domestic (rather than Greek) milk.