This study investigated the effect of different treatments (centrifugation and filtration; heating; adulteration with sugar syrups, and storage) and collection variables (year and region of the country) on the physicochemical properties of 44 Hungarian acacia honeys. The characteristics measured were diastase activity, hydroxyl-methyl-furfural (HMF), total phenolic content (TPC), electrical conductivity (EC), colour, pH, proline, moisture, sucrose, fructose and glucose contents, and concentration of eleven elements (As, B, Cd, Cr, Fe, K, Mg, Na, P, S, Zn). Centrifugation and filtration reduced the concentration of all examined parameters, except for moisture. Heating reduced diastase activity, proline and total phenolic concentrations and increased HMF concentration and colour value. Adulteration with sugar syrups had adverse effects on the diastase activity, proline, moisture and sugar concentrations, EC, colour and pH. Two-year storage reduced diastase activity, HMF, proline and TPC concentrations and increased sucrose concentrations. The collecting area influenced Na, Fe and As concentration, but the collecting year had no effect on the examined parameters. It is concluded that method and region of honey collection, duration of storage and processing all have major effects on the quality of acacia honey. Applied sugar syrup, although it affected honey quality, would be difficult to detect in the finished product.