Polyphenolic content, flavonoid content, and free flavonoid aglycon compounds were determined in 11 samples of Spanish honeybee-collected pollen. Adequate extraction was obtained with ethyl acetate in the determination of free flavonoid aglycon. Recovery (>83.6%), within-run repeatability (<6.67%), between-run reproducibility (<8.73%), and detection limits (1.4--1.9 mg/kg) were satisfactory. A total of 15 compounds were separated with gradient reversed phase HPLC, and 13 were identified and quantified using diode array detector. The most predominant compounds were flavonoid glycosides, mainly flavonols. Eighty-two percent of the samples contained at least 14 of the phenolic components, primarily rutin, quercetin, myricetin, and trans-cinnamic acid as free aglycons. Total phenols were present, at levels of >0.85 g/100 g in the form of non-tannins, and flavonoids of >0.35 g/100 g, using spectrophotometric procedures. Rutin is the best identifier of free flavonoid aglycon compounds. A minimum quantity of 200 mg/kg of rutin is suggested to guarantee the nutritional and biological properties required in the European market.

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The enzymatic activities of 147 samples of commercially produced Spanish poly¯oral and mono¯oral honeys are reported. Important variations in invertase activity and peroxide accumulation were determined to obtain objective information related to honey quality. Variations from 4.04 (Robinia pseudoacacia) to 25.61 g sucrose hydrolysed per 100 g h À1 (SN) (Castanea sativa) and from 11.31 (Erica vagans) to 45.25 mg H 2 O 2 g À1 h À1 (Hedysarum coronarium) were detected, with a range from 10.57 to 46.2 SN in poly¯oral honeys. Honeys from Erica spp had different invertase activitiesÐ high for E cinerea (18.3 SN) and low for E vagans (8.36 SN). The different heating processes of honey have been evaluated to determine the best treatment for preserving invertase activity. The hydroxymethylfurfural content is not a suf®ciently good indicator of the degree of deterioration of honey. Another objective was to assess the use of invertase activity in honey quality legislation.

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