Purpose Product packaging visually distinguishes products, making it a key determinant of a product’s success. This study examines two highly prominent packaging elements – colour and shape – of hedonic foods and their combined effects on consumers’ sensory expectations, such as the perceived sweetness, and their subsequent purchase intentions. Design/methodology/approach Study 1 conducted an experiment to examine the interaction effect between packaging colour (red vs blue) and shape (round vs angular) on consumers’ sweetness expectations and purchase intentions, with product-related perceptions serving as mediators. Study 2 used a survey involving a choice task to examine differences in consumers’ preferences between round-red and angular-red packaging, incorporating shape-related perceptions. A two-way between-subjects ANOVA, moderated mediation and binary logistic regression analyses were employed for data analyses. Findings Colour and shape interactively influenced sweetness expectations, with shape’s effect being more pronounced for blue packaging than red packaging. Moreover, the enhanced sweetness expectations triggered by packaging increased purchase intentions by amplifying expected food enjoyment and perceived package attractiveness. Furthermore, consumers preferred the round-red packaging to the angular-red packaging when focusing on sweetness, colour–shape congruency and package attractiveness; the angular-red packaging was favoured when consumers focused on package typicality. Originality/value This research advances the body of knowledge on consumer responses to product packaging by providing insights into the combined effects of the colour and shape of packaging for hedonic foods. Our findings highlight the importance of strategic packaging design while considering the combined impacts of colour and shape.