Finding the optimum treatment procedure to delay honey crystallization without reducing its quality

•One year study in honey to estimate the best procedure to delay crystallization.•Six different pretreatment procedures investigated.•Time differentiation of the selected quality parameters of honey were determined.•Storage of honey at −18 °C extended the shelf-life of honey. The current study investigated the effect of different thermal and non-thermal procedures for the estimation of the optimum conditions of treatment of different honey types (erica, cotton, thyme, eucalyptus and pine honey) to avoid or delay crystallization without losing the nutritional benefits of honey. Different physicochemical parameters, such as pollen analysis, hydroxymethylfurfural (HMF), diastase activity, acidity, and total phenolic compounds were used as quality indicators. The different treatment procedures were evaluated in different honey types and in different time periods. It was proved that to achieve a non-crystallised product that lasts over a year, samples must be heated at 72 oC or stored at −18 °C. However, only by storing samples at −18 °C kept the nutritional benefits of honey and provide similar results with the fresh unheated samples. All procedures were examined in a long-term period (one year) in order to have a complete and accurate result.