Frozen burger sales fall 43pc amid horse meat scandal The data also showed mixed fortunes for the big four supermarkets - Asda, Morrisons, Sainsbury's and Tesco. Sainsbury's was the only one of the big four supermarkets to increase its market share rise in the 12 weeks to February 17, with a growth rate of 4.6pc. Tesco, which has become embroiled in the horse meat scandal, saw its share in the market come under pressure falling from 30.1pc a year ago to 29.7pc now, but that that was not necessarily as a result of the scandal, Kantar said. "It might seem natural to attribute this decline to the horsemeat contamination; however, Tesco undertook heavy promotions this time last year, where consumers received a £5 voucher when they spent £40, and not repeating this offer will have adversely affected its share," Mr Garner said. Tesco was the first major retailer to withdraw its frozen burgers, after it was discovered that horse meat accounted for approximately 29pc of the meat in the supermarkets Everyday Value Beef Burgers. Morrisons was the only retailer to post a sales decline in the 12 weeks, due in part to easing Christmas demand, a lack of convenience stores and no online presence. It has since announced a decision to buy some Blockbuster video stores to convert into metro outlets. Meanwhile, Waitrose and Aldi delivered all-time record shares in the 12 weeks of 4.8pc and 3.3pc respectively. Mr Garner said this indicated that market polarisation and the 'two nations' consumer climate continues. So far, companies embroiled in the crisis include Tesco, Asda, Aldi, Whitbread, Findus, Birds Eye, Ikea and Sodexo, which supplies food to schools, care homes and the armed forces.