Adulteration of honey is a major problem in the food industry. The purpose of the present study was to classify different types of monofloral honey based on physicochemical characterization and analysis of phenolic compounds coupled with chemometrics methods. The methods for classification were trialed on a wide range of honey samples from different floral origins. For thyme, jujube, coriander, barberry, acacia and alfalfa honey samples, principal component analysis combined with discriminant analysis (PCA-DA) and partial least squares combined with discriminant analysis (PLS-DA) were trialed. The results indicate that the botanical origin of the honey affects the profile of flavonoids and phenolic compounds. For example, jujube honey samples had the highest amounts of hesperetin and chrysin, while thyme honey had the maximum amount of caffeic acid; the highest levels of quercetin and p-coumaric acid were found in coriander honey. To reduce the numbers of independent variables for modeling, the principal component analysis (PCA) algorithm was used. The three scores extracted from PCA had 83.17% variance. The classification results show that PLS-DA was successfully used to predict the class membership of honey samples (100%), but PCA-DA gave the lowest correct classification rate (97%).

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In this study, the kinetics of total antioxidant activity changes by DPPH radical evaluation, brown pigment formation (BPF), and phenol total with folin-ciocalteu reagent intestinal tract in heated alfalfa honey at different temperatures (45, 55 and 65 °C) over a period of 10 days it placed. The results showed that the amount of antioxidant activity, BPF, and total phenol content increased with increasing temperature and time. Also, the kinetics of changes in BPF and total phenol showed that these parameters follow a zero-order kinetics and the activation energy was 86.1 and 71.7 kJ / mol, respectively, at 45-65 °C. However, due to the diversification of antioxidant activity at different temperatures, second order, first order, and zero order kinetics were obtained at 45, 55 and 65 ° C, respectively. Honey heating at 65 ° C was more effective than 45 ° C and 55 ° C for all three parameters. The results showed that antioxidant activity was associated with an increase in both browning factors and total phenol, and also with increasing brown pigment formation, the total phenol content increased so that the highest amount of phenol was related to the darkest honey sample.