Reliability of food measurements – a South African perspective

Abstract 

 High quality analysis of food involves a comprehensive process, which includes proper sampling, validated methodology, experienced technical staff and the use of standard reference materials. Today there is more international emphasis not only on generating food composition data but also on data quality and the main issue is that South African data should be internationally recognized as acceptable and representative. Quality is multi-dimensional and should at least include aspects of accuracy, precision and representativeness. A major step forward is that laboratories can apply for accreditation, which involves, inter alia, documented, validated methodology, regular interlaboratory studies, the use of certified reference materials and the existence of a sound quality system. The South African National Accreditation System (SANAS) is a regulatory body in South Africa, which is internationally recognized. Assessment of laboratories against specific standards is performed regularly and laboratories have to comply with certain managerial and technical requirements. Once a laboratory is accredited, ongoing validation and verification of results as well as regular assessment ensure reliability of results and overall competency of the laboratory. With a quality assurance programme in place, the reliability of results of the Irene laboratory is beyond doubt and nutrient data could be included in food composition tables.