Determination of shelf life of chaste tree (vitex agnus castus) honey and pine honey

Chaste tree and pine honeys were bought from three different producers (natural) and three local markets (commercial). The honey samples were stored for 30 months at room temperature. The shelf life of the samples was estimated for indices of HMF and diastase activity. The values for HMF formation and diastase deactivation fitted to a zero-order reaction. The highest rate of HMF formation was observed in the chaste tree honey as 2.674±0.013 mg/kg/month while the least value was observed in the pine honey as 0.435±0.037 mg/kg/month. The maximum diastase deactivation was determined in the natural chaste tree honey as 0.613±0.000 DU/kg/months and the minimum was 0.318±0.002 DU/kg/month for the commercial chaste tree sample. In terms of HMF, all honeys except commercial chaste tree honey, have exhibited longer shelf life than 30 months of storage. The results showed that the shelf life of the commercial honeys depend on the botanical origin, pH, electrical conductivity, temperature and storage.