# Physical and Microbiological Characteristics and Antioxidant Activity of Honey Bee Pollen
## 4 Discussion
Among the monofloral pollen studied, the highest water activity, with a value of 0.389 \(\pm\) 0.000, was found in bee pollen from rye flower (RF), phacelia (PHA), with 0.383 \(\pm\) 0.003, and autumn raspberries (AR), with 0.363 \(\pm\) 0.001, all of which were slightly above or close to the permissible norm. In comparison, the lowest water activity (0.228 \(\pm\) 0.001) was found in rapeseed pollen (RS). Of all the analysed multifloralpollen samples, the highest water activity (0.324 \(\pm\) 0.001) was found for the Tervete district collected bee pollen (MF3) sample, whereas the lowest water activity (0.187 \(\pm\) 0.002) was determined for the bee pollen (MF1) sample collected in the Broceni District. The water activity of the analysed multifocal bee pollen samples was not higher than the permissible norm (0.38), but it differed significantly (\(p\) < 0.05) between the analysed pollen samples. These differences could be partly explained by the moisture content of the bee pollen pellets; there was a moderate correlation (\(r\) = 0.68) between the moisture content and water activity of the samples analysed. Red clover bee pollen sample (Table 1) had low moisture content (6.62 \(\pm\) 1.24) and high water activity (0.322 \(\pm\) 0.001), while fava bean pollen demonstrated the opposite trend, having high moisture content (9.47 \(\pm\) 0.44) and low water activity (0.294 \(\pm\) 0.005). This mainly may be due to the ability of specific pollen to bind water. If the water binding ability is low, more free water is present, which results in higher water activity. These differences can also be explained by the weather conditions during the harvest season and the place of harvest, as well as the treatment and storage conditions (including the duration of storage) until the time of the experiments. The optimal water activity of dried bee pollen should not exceed 0.38 [27]. With this amount of water activity, the potential risk of microbiological contamination of bee pollen by various yeasts and fungi is reduced, and pollen is safe for longer storage. As pollen is very hygroscopic, external environmental factors can significantly affect its quality. According to [PERSON] et al. [28], moisture content and microbiological safety should be the key parameters in bee-collected pollen quality control. Our study indicated a moderate correlation between (\(r\) = 0.64) bee pollen moisture content and _Enterobacteriaceae_ counts, as well as between moisture content and total plate count. This confirms the need for sufficiently low water content, requirements of which is less than 4% in Brazil, less than 6% in Switzerland and Poland, not exceeding 8% in Uruguay, and a maximum of 10% in Bulgaria [11]. Microbiological analyses proved that in the analysed bee pollen samples, _Enterobacteriaceae_ ranged from 14.0 cfu/g in willow pollen to 82.0 cfu/g in phacelia pollen, with the highest value of total plate count detected in autumn raspberry pollen (\(7.35\times 10^{2}\) cfu/g). In comparison, the indicated values by [PERSON] et al. [11] are within the permissible range, below 100 cfu/g and \(10^{5}\) cfu/g for _Enterobacteriaceae_ and total plate count, respectively. This confirms the suitability of pollen studied for human consumption. There are no international legal norms established for microbiological control of pollen. Although national standards have been established in several countries, in Latvia, there are no established specific norms or total microorganisms (MAFAM) and _Enterobacteriaceae_ in bee pollen. The high number of AMR cases with isolates that were resistant to ampicillin (7 cases) and penicillin (8 cases) points to an environmental effect because these antibiotics are not normally used in apiaries. This is in agreement with the study of [29], who reported about 80% resistance of _Staphylococcus aureus_ to penicillin. In our study, _S.