A true tomato ketchup needs nothing in it except tomatoes, sugar, vinegar and salt, plus herbs and spices – so keep a sharp eye on the ingredients label. Anything else listed is chiefly for the convenience of the manufacturer, and while they may argue it keeps prices down for you, you can bet it will keep profits up for them. Water, Tomato Concentrate, Sugar, Modified Starch, Acid: Acetic Acid, Salt, Acid: Citric Acid, Preservative (Potassium Sorbate), Colour (E150d), Rapeseed Oil, Sweetener (Sucralose), Natural Flavourings. Granted, preservatives such as potassium sorbate will help the ketchup keep a bit better out of the fridge (arguably a benefit for us, too), but they aren’t necessary. Most ketchup will keep a month out of the fridge and at least six months in the fridge. As for the rest of the additives on the ingredients list – their role, generally, is to make up for deficiencies elsewhere, such as modified starch instead of tomatoes and acetic acid instead of vinegar. Either way, ketchup arrived over here with British sailors in the 17th century and our early versions were made with spices plus anchovies, oysters, and whatever fruits and vegetables were to hand, bearing little relation to modern ketchup. British producer Geo Watkins ( geowatkins.com) still makes mushroom ketchup, along with another long-forgotten classic, anchovy sauce. The mushroom version looks more like Worcestershire sauce, but it’s mild tasting and a great addition to all sorts of soups and braises. The top brand is Heinz, to ketchup what Hellmann’s is to mayo and Coke is to cola. But it’ll cost you: a recent report by Which? had Heinz ketchup topping its league table for food inflation among top brands, with a price increase of 53 per cent on two years ago. For some people, the distinctive bottle holds the taste of their childhood – but with prices this high, nostalgia may not be enough to keep on putting it in the trolley. So, is the taste irreplaceable? Or could another, cheaper ketchup hit the spot?