Patterns of Raw Milk Adulteration in Informal Markets in Malawi: A Multivariate Statistical Analysis

Milk adulteration is a common fraud practiced by milk producers. In Malawi, information about its extent is limited. A cross-sectional study was conducted across three major milk- producing districts in Malawi to assess the prevalence and levels of predominant adulterants. Adulterant testing was performed using semi-quantitative milk test strips, except for water, which involved a combination of flow/drop and organoleptic observations followed by lactometry. Data were analyzed in R. The most prevalent adulterant was water (91%, n = 350), followed by neutralizer (91%, n = 350) and urea (4%, n = 14). Samples from vendors and Thyolo District had the highest prevalence of neutralizers (90%, n = 64). In comparison, water adulteration was highest (100%, n = 78) in Lilongwe. Compared with farmers, vendors had higher odds of water (aOR = 8.12) and neutralizer (aOR = 2.19) adulteration. With reference to Thyolo, the odds of water adulteration (aOR = 4.06) were higher in Lilongwe, while for neutralizer, Lilongwe (aOR = 0.20) and Karonga (aOR = 0.11). Co-occurrence of urea, neutralizers, and water was associated with vendors and Thyolo. Samples from vendors and farmers in Lilongwe and Karonga had similar neutralizer levels (p > 0.05). These findings underscore the need to apply interventions to address milk adulteration in Malawi with the hope of scaling them to other countries.