The essence has natural and artificial flavouring in it. The sweetener contains the artificial sweetener acesulfame potassium (also known as acesulfame K), along with dextrose sugar as a bulking agent.
It is also worth pointing out that our cider kits contain sulphites which are not only a legally recognised allergen themselves, but they’re also another of the sulphur-containing compounds listed above.
Please note, that the full ingredients for the essence and sweetener sachets are listed on the packaging - please check those for any of your own allergens and concerns.