FIMIX-PLS segmentation of Islamic brand consumption in a multicultural market: extending the theory of planned behavior as an information–motivation–behavior framework

Purpose Islamic branding research has largely relied on models developed in Muslim-majority contexts and often assumes homogeneous consumer responses. Addressing this limitation, this study aims to examine Islamic brand consumption in a multicultural setting by extending the theory of planned behavior (TPB) with Islamic brand knowledge (IBK) and Islamic brand health benefits (IBH) as informational mediators, while explicitly accounting for unobserved heterogeneity through finite mixture partial least squares (FIMIX-PLS) in Thailand. Design/methodology/approach A cross-sectional survey of 688 Thai consumers, including Muslim and non-Muslim respondents, yielded 637 valid responses analyzed using partial least squares structural equation modeling. FIMIX-PLS was then applied to detect unobserved heterogeneity and estimate segment-specific structural relationships within the extended TPB framework. Findings Subjective norms and perceived behavioral control were the strongest predictors of Islamic brand consumption, while IBK and IBH also showed significant positive effects. Compliance, Islamic brand by customer and country of origin influenced behavior primarily through indirect cognitive, affective and normative pathways. The model explained 70.6% of the variance in consumption behavior. FIMIX-PLS identified two latent segments, confirming unobserved heterogeneity. One segment was driven mainly by country of origin through normative and control pathways, reflecting an identity-based logic. The other was shaped more by the Islamic brand, by customer knowledge and by perceived health benefits, indicating an informational and health-oriented logic. Originality/value Building on previously published research that established the predictive validity of an extended TPB model using the same Thai consumer data set, this study advances Islamic marketing by examining mediation and unobserved heterogeneity through IBK, IBH and FIMIX-PLS.