Thirty chestnut and twenty‐six of floral honeys were collected from different regions of Turkey. The amounts of phenolic compounds in honeys were determined by high performance liquid chromatography‐diode array detection. The antioxidant capacities were determined by ABTS and CHROMAC methods. The total phenolic content of honeys were determined by spectrophotometric method using the Folin‐Ciocalteu reagent. Caffeic, protocatechuic, and p‐hydroxybenzoic acids are the major phenolic compounds with the contents of 44.52, 17.48, and 21.50 mg/kg, respectively in chestnut honeys. Chestnut honeys exhibited the higher antioxidant and better antimicrobial activities, and than the floral honeys. Floral honeys contain similar amounts of propolis flavonoids such as pinocembrin, chrysin, and galangin. The results show that these flavonoids can be used as chemical markers in honey samples. Practical applications Honey is an important natural product that contains major compounds including glucose and fructose and minor components such as amino acids, organic acids, enzymes, vitamins, proteins, phytochemical substances mainly flavonoids and other phenolic compounds. Plants are important sources of natural compounds that contain polyphenolic derivatives such as flavonoids and phenolic acids. These bioactive compounds can be transferred from plants to honey. Polyphenolic compounds were recognized as the major components responsible for health‐promoting properties of honey. This article evaluates the antimicrobial and antioxidant activities and phenolic compounds of chestnut and floral honeys. The chemical content and biological properties of honey have been studied extensively in many but there are a few studies in our knowledge about the determination of phenolic compounds in chestnut honey.

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The distribution and stability of aflatoxin M1 (AFM1) in Kashar cheese were investigated. Raw milk samples were spiked with AFM1 at the levels of 50, 250 and 750 ng/L. Distribution of toxin in milk, cheese curd, whey, kneading brine and cheese, and its stability during ripening were determined by high‐performance liquid chromatography. Concentrations of AFM1 in curds for each contamination level were 2.93, 3.19 and 3.37 times higher than those in milk. After syneresis, the percentage distribution of AFM1 was 40–46% in curds and 53–58% in whey indicating that relatively higher concentration of toxin passed to whey. Moreover, by the kneading process approximately 2–5% of AFM1 passed to kneading brine. Compared to the initial spiking level, the percentage of toxin in cheeses varied between 35–42%. Over a 60‐day storage period, there was no decrease in the concentration of AFM1, suggesting that the toxin was stable during ripening.

Honey samples, collected from the Southern Marmara region of Turkey, were analysed for erythromycin residues by liquid chromatography-mass spectrometry using electrospray ionization in the positive ion mode (LC-ESI-MS). Fifty samples, comprising chestnut, pine, linden and multi-flower honeys, were collected directly from hives and analyzed. The limit of detection and quantification were 6 and 20 ng g(-1), respectively, and recovery ranged from 85 to 89%. Four of the honey samples (8%) were found to be contaminated with erythromycin residues at concentrations ranging from 50 to 1776 ng g(-1). An erythromycin-fortified cake feeding assay was also performed in a defined hive to test the transfer of erythromycin residue to the honey matrix. In this test hive, the residue level in the honey, 3 months after dosing, was approximately 28 ng g(-1).

Chestnut bee pollen is a high antioxidative natural bee product. In this study the phenolic compounds in chestnut bee pollen were determined by HPLC-DAD system. Ethanol, water and methanol were used for the extraction of antioxidant compounds from chestnut bee pollen. The total phenolic contents and antioxidant capacities of extracts were determined by Folin-Ciocalteu, CHROMAC (Cr(VI) reduction antioxidant capacity) and FRAP (ferric reducing antioxidant power) methods, respectively. When compared the amounts of phenolic compounds and spectroscopic results (total phenolic contents and antioxidant capacities), the most suitable solvent was found ethanol for the extraction of antioxidant compounds from bee pollen. The major phenolic compounds in the chestnut bee pollen were determined as pinocembrin, chrysin, galangin and hyperoside with the contents of 1.246, 0.332, 0.122 and 0.516 mg/g of bee pollen, respectively. And also it was determined that the chestnut bee pollen was inhibited 11% of DNA oxidation in Fenton medium.