Ověření metod stanovení přirozených a cizích amylas v medu
Honey is a traditional food with unique nutritional and sensory properties. On the Czech market, however, a large amount of adulterated honey still appears. The presence of foreign amylases indicates the addition of starch syrups. Our work focuses on the verification of selected methods for determination of amylases activity in honey. The methods were tested on samples containing defined additions of amylases (α-, β- or γ-amylase) and on the real samples from the Czech market. α-Amylase activity was measured by 3 methods (Schade method, Phadebas method, Alpha Amylase Megazyme test). Beta Amylase Megazyme test was used for determination of β-amylase. The results of the measurements show that the Schade and Phadebas methods are not specific to α-amylase, as opposed to the Alpha Amylase Megazyme test. For determination of foreign amylases (β- and γ-amylase) derived from starch syrups, a Beta Amylase Megazyme test containing p-nitrophenyl-β-ᴅ-maltotrioside substrate is advisable. The analyses carried out show that the methods based on the specific enzyme-catalyzed reaction are suitable for the assessment of honey quality and authenticity, and together with other parameters could contribute significantly to detection of adulterated samples.