What is the difference between cream cheese and quark?

Quark is a soft white and unaged cheese with a relatively mild flavour. The texture of quark varies according to its fat content. The higher the fat content the smoother and creamier the texture. Production of quark involves adding lactic acid bacteria to curdle the milk, followed by the straining of whey from the curd. Cream cheese is also a fresh soft cheese, with a smooth and spreadable texture, and a slightly acidic flavour.

Cream cheese is made in a similar way but from a combination of cream and milk, giving it a higher fat content. However, after whey separation, the curd is typically heated to about 80-85 °C; salt and gums (stabilisers) are generally added and blended with the hot curd, prior to cooling and packaging. Stabilisers added to cream cheese include xanthan, locust bean or guar gum.

The shelf-life of cream cheese at refrigerated temperature is typically 3-6 months, and is much longer than that of Quark (about 1 month) because of the heat treatment of curd during the manufacture of Cream cheese.