Vraag
Gepost op: 27 mei 2013Houdbaarheid van benzylbenzoaat crème
Antwoord
Benzyl benzoate degrades to benzoic acid and benzyl alcohol. These degradation products are less active against scabies mites. They are relatively non-toxic and act as preservatives in the lotion. Baker and co-workers found low contents of benzyl benzoate in some emulsions (formulated according to the British Pharmacopoeia) but only small amounts of the degradation products. They assumed that the low concentrations of benzyl benzoate did not result from degradation, but from partial separation of the emulsion at the time of dispensing (13). Benzyl benzoate emulsion should always be well mixed before dispensing and before application. Hydrolysis of benzyl benzoate in emulsions is expected but is limited as there is little contact with water. The only possible contact of benzyl benzoate is at the interface of the oil and aqueous phases, because benzyl benzoate is not dissolved in the water but in the oil phase. The emulsion is therefore suitable for storage during longer periods of times. However, for reasons of physical and microbial stability, we recommend to use benzyl benzoate emulsion within 3 months after production.
Deze termijn zal ook gelden voor eenn "stabiele" crème. Misschien zes maanden , maar gegevens zijn niet beschikbaar. Zeer belangrijk in deze context zijn de hygiënische maatregelen, die genoem worden bij de bereiding en de verpakking van de crème. Geen voorraadpotten !