Differentiating emotions in the theory of planned behaviour: evidence of improved prediction in relation to sustainable food consumerism

The theory of planned behaviour (TPB) and its extensions are often used to explain intentions to perform sustainable behaviours. Emotions can provide the impetus for action and should be considered in high-involvement situations, such as sustainable food purchase decisions. Therefore, the aim of this research work was to investigate whether the addition of different types of emotions (self-related, social and pro-active) to the TPB main constructs – attitude (ATT), subjective norm (SN) and perceived behavioural control (PBC) – improves the explanation of intention to make two sustainable food purchase choices: purchase Fairtrade (FT) products and purchase through solidarity purchasing groups (SPGs).

The present investigation was conducted by two studies using online questionnaires and focussing on purchasing FT food products (Study 1) and purchasing food through SPGs (Study 2). Stepwise regression models were run to explain the intention to purchase FT products (Study 1; N = 240) and the intention to purchase through SPGs (Study 2; N = 209).

Results show that emotions increase the predictive validity of the TPB model. The study also highlights the importance to distinguish between different types of emotions. Amongst those considered in both studies, only pro-active emotions play a significant role in predicting food purchasing intention. Results encourage further investigation of the role of emotions in TPB-based models for predicting sustainable food purchase choices.

The measurement of the three classical antecedents of the TPB model (ATT, SNs and PBC) performed by single items can be considered the main limitation of this work. In future research, instruments made up of more items measuring these three theoretical dimensions should be used. In addition, it would be important to conduct an analysis of the beliefs that determine ATTs, norms and perceived control.

Different from previous studies that considered emotions in extension of the TPB model to explain sustainable behaviours, the present work separately analysed the role of three different kinds of emotions (self-related, social and pro-active) in explaining sustainable food behaviours.