sugar
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Brewing sugar (Dextrose) ferments slightly more cleanly than table/granulated sugar, but there's not a lot of difference really. Either is fine for priming.
For best results, use Spraymalt instead of sugar when making a kit up. Using sugar makes the beer thin, and gives it that unmistakeable 'homebrew' taste. If you can't get hold of Spraymalt, Wilko's sell Beer Kit Enhancer in 1Kg bags, which is half Spraymalt and half brewing sugar - a bit of a cheaper compromise.

Brewing sugar (Dextrose) ferments slightly more cleanly than table/granulated sugar, but there's not a lot of difference really. Either is fine for priming.
For best results, use Spraymalt instead of sugar when making a kit up. Using sugar makes the beer thin, and gives it that unmistakeable 'homebrew' taste. If you can't get hold of Spraymalt, Wilko's sell Beer Kit Enhancer in 1Kg bags, which is half Spraymalt and half brewing sugar - a bit of a cheaper compromise.