Consumer group Which? has condemned some major retailers for bulking up chicken in sandwiches after analysing the contents of 26 lines.

Researchers found only one sandwich, sold by Asda, in which the meat ingredient was 100% chicken. In other sandwiches, bought at stores including Marks & Spencer, Tesco and Waitrose, meat content ranged from 94% to 99% and was found to have been bulked up with ingredients including rapeseed oil, potato starch, water and chicken stock. Which? says a chicken and stuffing sandwich, sold at BHS, was the worst offender. Labelled “100% breast meat”, it included water, glucose syrup, thickener, salt and salt compound.

Which? also looked at salt content as it surveyed chicken sandwiches from a selection of retailers. It found most salt in a Tesco healthy living chicken salsa wrap, which had 3.2g salt per pack – over half the UK recommended daily limit of 6g.

The lowest was found in Waitrose’s Perfectly Balanced Tzatziki Chicken sandwich. On average the sandwiches contained nearly 2g of salt each.