The present invention is directed to a powder acid-sanding composition comprising partially neutralized polycarboxylic acid and at least one of a sugar and sweetener for confectionery products. The partially neutralized polycarboxylic acid improves the stability in terms of acid migration into the candy and moisture uptake from the environment. The invention is further directed to a method for acid-sanding of confectionery products using a partially neutralized polycarboxylic acid and to the products obtained. The acid-sanded confectionery products as for example hard and soft candies of the invention have an improved shelf life. The present invention also results in acid-sanded confectionery products with an immediately felt sour taste and of a constant strength at bringing it in the mouth and digesting it. Soft-candies as e.g. gelatin or starch-based candies with an acid-sanding according to the invention have a very stable acid profile at the surface of the acid-sanded candies since acid migration into the soft candy is decreased or even prevented.