Cravendale has launched Free Milk Fridays, a social media campaign giving away 200 bottles of milk every Friday from 1 July ­until October.

Each week, 100 Twitter followers and 100 Facebook fans are in with a chance of winning. Twitter followers need to wait for a tweet issued on Friday mornings, and retweet it. Followers will then be selected at random to receive a voucher for a free one-litre carton.

Similarly, Cravendale's Facebook page will show a special 'tab' every Friday, with the first 100 fans to click on it given a voucher.