The influence of ethical values and food choice motivations on intentions to purchase sustainably sourced foods

This study examined a three-step adaptation of the Theory of Planned Behaviour (TPB) applied to the intention of consumers to purchase sustainably sourced food. The sample consisted of 137 participants, of which 109 were female, who were recruited through a farmers market and an organic produce outlet in an Australian capital city. Participants completed an online questionnaire containing the TPB scales of attitude, subjective norms, perceived behavioural control and intention; measures of positive moral attitude and ethical self identity; and food choice motives. Hierarchical multiple regression was used to examine the predictive utility of the TPB in isolation (step 1) and the TPB expanded to include the constructs of moral attitude and ethical self-identity (step 2). The results indicated the expansion of the TPB to include these constructs added significantly to the predictive model measuring intention to purchase sustainably sourced food. The third step in the adaptation utilised this expanded TPB model and added a measure of retail channel (where consumers reported buying fresh produce) and 9 food choice motives, in order to assess the predictive utility of the inclusion of choice motivations in this context. Of the 8 food choice motives examined, only health and ethical values significantly predicted intention to purchase sustainably sourced food. However, with the addition of food choice motives, ethical self-identity was no longer a significant predictor of intention to purchase sustainably sourced food. Overall the adapted TPB model explained 76% of the variance in intention to purchase sustainably sourced food.