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The aim of the present study was to compare the physical, chemical and biological parameters and the microbiological quality of bee-pollen samples treated with different dehydration processes and to correlate the results. The samples came mainly from Eucalyptus (Myrtaceae) and Eupatorium (Asteraceae) plants. The dehydration conditions of the samples influenced the L*a*b* colour parameters and the biological value. Unlike the protein and lipid content, the glucose and fructose content were unaffected. The vitamin E content (27.2 ± 0.3 mg/g, 27.5 ± 0.4 mg/g) in oven-dehydrated samples with forced air circulation was significantly lower (P < 0.05) compared with lyophilized samples (37.5 ± 0.2 g/100 g, 53.7 ± 3.9 g/100 g). Overall, the results were inconclusive for vitamin B complex, minerals and microbiological indicators. There was a positive correlation between the colour parameters L* and b* and the total phenolic content, as well as between phenolic content and the antioxidant and antimicrobial capacity. The data indicate that lyophilization might be a viable alternative to the current process, resulting in dehydrated bee-pollen with higher biological activity.

Fifty six Brazilian bee pollen samples were characterised, and their botanical and geographical origins were studied. The samples were also classified based on physicochemical and biological properties. The characterisation was done using Soxhlet extraction and micro-Kjeldahl methods, ashing at 550°C, transmittance, microscopy, spectrophotometry, inductively coupled plasma optical emission spectrometry and high-performance liquid chromatography. As expected, the values of proteins (7.9-32.2 g/100 g), lipids (3.2-13.5 g/100 g), ash (1.9-3.6 g/100 g), carbohydrates (54.9-82.8 g/100 g), K (3.4-9.8 g/kg), Ca (0.9-4.1 g/kg), Mg (0.6-2.4 g/kg), Fe (46-1180 mg/kg), Na (20-374 mg/kg), Mn (25-215 mg/kg), Zn (30-101 mg/kg), Cu (7.4-19.7 mg/kg), total phenolics (6.5-29.2 mg GAE/g) and flavonoids (0.3-17.5 mg QE/g) as well as the phenolic profiles varied among the samples. In general, the products had high antioxidant capacity (ORAC: 133-563 μmol TE/g; DPPH: 9.4-155 μmol TE/g) and the antimicrobial capacity varied according to the sample and microorganism tested. The instrumental colour parameters could be used as indicators of some minerals. Based on multivariate approaches, bee pollen from Southern Brazil seemed to have a higher biological potential, whereas products from the Northeast region had higher calcium and magnesium levels. Similarities were identified in bee pollen containing C. nucifera or Brassica, and monofloral bee pollen seemed to have higher mineral content than heterofloral bee pollen.

Contamination of bee-pollen can occur during production, collection and processing, but there are few studies of the microbiological quality of this product. Brazil is an important producer of dehydrated bee-pollen, therefore, a diagnosis of the microbiological status is important to ensure the safety of many consumers. Salmonella sp., genus Clostridium, coagulase-positive Staphylococcus, Escherichia coli and even some yeast species are micro-organisms of public health concern and their presence must be monitored. Furthermore, the determination of spoilage micro-organisms indicates whether the production and the processing practices carried out by beekeepers and warehouses were adequate.

The objective of this study was to determine physicochemical and phenolic profiles as well the antioxidant and antimicrobial capacities of monofloral bee pollen samples from Brazil. Traditional methods were used. The phenolic profile was determined by high‐performance liquid chromatography‐mass spectrometry (HPLC‐MS). The protein (10.6–33.9 g/100g), lipids (3.2–8.3 g/100g), ashes (2.6–3.8 g/100g), total phenolic (5.6–29.7 mg GAE/g), and total flavonoid (0.3–19.0 mg QE/g) values were variable, even between products with the same botanical origin. The minerals analyzed were found in amounts varying between 10 mg/kg and 9.1 g/kg. Each product presented specific color parameters. Myrcia bee pollen presented the greater antioxidant capacity, and Mimosa scabrella bee pollen from Santa Catarina state was the most efficient in inhibiting bacteria and yeasts. Among the compounds identified by HPLC‐MS, flavonoid 3‐O‐glycosides predominated. The physicochemical and phenolic profiles of each sample were distinct, and there was no pattern between monofloral products of the same pollen type. Practical applications This manuscript reports physicochemical parameters, the biological potential, and the phenolic profile from HPLC‐MS of some unknown monofloral bee pollen produced in Brazil. In addition to the possibility of the identification of phenolic compounds using a reliable technique, the current study helps to clarify one of the main questions of apicultural product researchers: Would monofloral bee pollens of the same botanical origin have similar profiles? Besides this, these results can increase consumer interest in this product and thus have positive impacts on apiculture in Brazil.