We are happy to announce that the 8^th edition of NMKL method No. 67 now has been published. In the 8^th edition, the title of the method is changed back to “Presumptive Bacillus cereus. Determination in foods.”, and errors from the 7^th edition are corrected. In the 8th edition, it is still possible to use blood agar in parallel with selective agar, especially, when low counts are expected.

Unfortunately, NMKL has decided to withdraw the method “NMKL 67, 7^th Ed. 2020 Bacillus cereus group”. We urge customers to use the 6^th Ed. until the 7^th Ed. has been revised and re-published early 2021.

NMKL acknowledges that a clarification concerning reporting results as ‘Bacillus cereus group’ is needed and that there are discrepancies between the Norwegian/Scandinavian and the English text. If the 7^th Ed. has already been applied, please express results as ‘presumptive Bacillus cereus’. There are no known issues with technical performance of the method.

We sincerely apologize for the inconvenience and thank our observant customers for constructive feedback.

NMKL participated in the Codex Committee on Methods of Analysis and Sampling (CCMAS) webinar series November 23-25 and our presentation is now available.

The standardized analytical method for folate in food has traditionally utilized quantification by a microbiological assay, a method that cannot distinguish between the different folate vitamers. This new NMKL method enables quantification of total folate based on quantification of six folate vitamers which contribute to the main folate activity. Besides providing the information about the content of the specific folate vitamers, the method includes fast extraction of folates from food that may be carried out within eight hours.

The essential part of the method is using a pure γ-glutamyl hydrolase, which enables efficient and fast break-down of the polyglutamates to monoglutamates. LC-ESI-MS/MS quantifies monoglutamates by use of 13C5-labelled internal standards.

A collaborative study was conducted in summer 2019 with participation of eight laboratories from seven European countries. The method has been successfully validated for total folate determination in strawberries, spinach, lentils, yogurt, liver and infant formula, providing acceptable Horwitz ratio values (0.60-1.94). The results are published in Food Chemistry (Ložnjak Švarc, P; Oveland, E; Strandler, HS; Kariluoto, S; Campos-Giménez, E; Ivarsen, E; Malaviole, I; Motta, C; Rychlik, M; Striegel, L; Jakobsen, J (2020): Collaborative study: Quantification of total folate in food using an efficient single-enzyme extaction combined with LC-MS/MS. Food Chemistry, 333, 127447).