Organic acids content, sugars content and physicochemical parameters of Romanian acacia honey

Abstract

Introduction. Some elements of a honey are added by bees; others occur after the maturation of honey. The physicochemical parameters, pollen content, sugars content and organic acids content were determined for Romanian acacia honey. Materials and methods. 27 samples of acacia honey from 2020 were examined to determine the physicochemical parameters (moisture, electrical conductivity, pH, free acidity, color, HMF content) and sugars content using the methods proposed by the International Honey Commission. Organic acids composition was determined using the method proposed by Ozcelik. Results and discussion. The botanical origin of all samples was confirmed by melissopalinological analysis, each sample containing more than 45% Robinia pseudocacia pollen granules. According to Codex Alimentarius, moisture content should be lower than 20%, and for the analyzed samples the moisture content ranged from 16,66?20,74%. The pH of the acacia honey samples ranged from 3.61 to 5.33. The free acidity of acacia honey analyzed in this study ranged from 0.32 to 4.14 meq/kg. None of the analyzed samples exceeded the limit imposed by legislation. All honey samples showed similar lightness values (29.62?46.57). The maximum content of HMF in the samples was 23.20 mg/kg thus falling within quality requirements. A value of less than 500 μS/cm indicates a pure floral honey, and in this study the samples of acacia honey had electrical conductivity values between 94.8?405 μS/cm. In the acacia honey samples was identified a percentage of 68.35% monosaccharides, and a small percentage of sucrose (maximum 2.093%). The F/G ratio varied between 1.02 and 1.65 for the studied acacia samples and some samples can crystallize quickly because have high glucose content and the F/G ratio is about 1. In the samples with F/G values above 1.3 the tendency of crystallization is slower. Gluconic acid was the main organic acid in all samples (1.916?2.666 g/kg) followed by propionic and acetic acids. Succinic acid has the lowest concentration in the studied acacia honey samples. Conclusions. All the investigated honey samples (27 samples) met the quality criteria examined (moisture, pH, free acidity, HMF content, color and electrical conductivity) and the high percentage of pollen grains of Robinia pseudoacacia confirmed that the samples analyzed were monofloral acacia honey.