Scientific research demonstrates that monosodium glutamate (MSG) is neither solely found in Chinese food nor a cause for health panics. Nonetheless, such a narrative still persists in the public sphere. I conduct a rhetorical analysis of the original debate on MSG to illuminate how the process of genre uptake – the process of information selection and translation from medical discussion to popular news – facilitated this prejudiced understanding. In the original debate about MSG’s effects, doctors trivialized this issue via satire that was based on latent stereotypes of Chinese identity. Although performed as insider humor, these responses were sufficiently aligned to genre expectations so as to appear to outside readers as unquestionable medical fact. As this knowledge was taken up and disseminated in the public sphere, the markers of humor disappeared, but the prejudicial views remained. This case demonstrates how the process of genre uptake can perpetuate prejudiced ideological narratives even in the absence of overt discrimination.