What is the difference between butter and yellow fat spreads?

The term ‘yellow fat spread’ is broadly used to describe all spreadable fats such as butter, margarine and blended fat spreads, whereas butter is defined as having no less than 80 % milk fat, a maximum water content of 16 %, 1.5 % milk solids-non-fat and it can be salted or unsalted. Margarine is a solid, malleable emulsion, principally of water and fat from either vegetable and/or animal sources.

It is required to have a fat content of between 80-90 %, with reduced and low-fat versions also available. Margarine usually contains less saturated fat than butter and it is often fortified with vitamins A and D to mimic the composition of butter. Blended spreads have a similar composition to margarine and are available in a wide range of fat contents. With the exception of butter, yellow fat spreads usually contain additives, colouring agents and preservatives.