NG28 provides food microbiological testing services related to quality control samples, which are mainly used for method verification and confirmation, quality assurance of the testing process, etc., which can be used for blind samples for on-site review, supervisory review, reassessment and unannounced inspections by regulatory agencies, and can also be used Alleged samples or blind samples such as internal audit, daily quality supervision, quality assessment, personnel assessment, method comparison, personnel comparison, and equipment comparison in the laboratory.