The invention relates to a spray-dried powder formulation comprising particles that contain the following components i) to iii): i) a compound of formula 1, in which A represents a group selected from (I), (II) or (III), R and R' each representing hydrogen or in combination form a group selected from a single bond, --CH.sub.2-- and --O--, and in which X.sup.- represents a negatively charged anion, ii) at least one embedding material selected from the group consisting of mono- or disaccharides, oligosaccharides, polymers, sugar alcohols and cholesterol, iii) an organic, physiologically acceptable, sterically demanding acid, selected from the group consisting of ascorbic acid, a monovalent, divalent or trivalent carboxylic acid, preferably fumaric acid, oxalic acid, diacetic acid or a sterically demanding amino acid and a fruit acid or culinary acid, preferably citric acid, tartaric acid, malic acid, lactic acid, acetic acid, .alpha.-hydroxycaprylic acid or gluconic acid. The invention also relates to a method for producing said formulation and to the use of an organic, physiologically acceptable, sterically demanding acid, from the group consisting of ascorbic acid, a fruit acid or culinary acid, preferably citric acid, tartaric acid, malic acid, lactic acid, acetic acid, .alpha.-hydroxycaprylic acid or gluconic acid and a monovalent, divalent or trivalent carboxylic acid, preferably fumaric acid, oxalic acid, diacetic acid or a sterically demanding amino acid, for stabilising a powder formulation produced by spray-drying containing the aforementioned compound i) of formula 1 and a suitable embedding material ii).