‘Best before period once opened’ for honey samples from oceanic climates on the basis of their acidity types

Stability of food is of particular interest, as we should know the period for which a given food maintains its original quality. Acidity is a very important parameter as regards honey quality control. In this study we analysed a possible ‘best before period once opened’, regarding the evolution of acidity in honey throughout 30 months in samples from regions with oceanic climates. The study was carried out at room temperature (between 15 and 25 °C) by analysing all samples in duplicate each 5 months. We also researched the possible influence of induced granulation on the acidity evolution of honey samples, observing that as the analysis of variance showed significant differences at P‐value <0.05, this process had a significant influence on free acid and total acidity. All samples fulfilled the European Regulations regarding free acid, because no honey sample showed a free acid value higher than the limit of 50 meq kg^?1. Nevertheless, all honey samples suffered a continuous decrease of pH from 20 months on (averages: from 4.1 ± 0.25 at 20 months to 4.0 ± 0.23 at 30 months), and a continuous increase of both free acid (averages: from 27.6 ± 6.22 meq kg^?1 at 20 months to 33.5 ± 6.44 meq kg^?1 at 30 months) and total acidity (averages: from 42.5 ± 7.60 meq kg^?1 at 20 months to 44.7 ± 7.60 meq kg^?1 at 30 months). On the basis of acidity types, 20 months should be considered the ‘best before period once opened’ for honey from regions with oceanic climates.