Intervention studies: insights from quantitative, qualitative and ethnographic data
Intervention studies can provide deeper insights into behavioural change when quantitative outcomes are complemented with qualitative and ethnographic data capturing participants’ experiences in real-life contexts. This study aims to evaluate this approach by examining consumer responses to foods incorporating novel protein sources through a mixed-method intervention design.
Seventy-two couples were randomly assigned to one of two intervention groups and exposed to bar, granola and pasta products over three weeks, with consumption taking place in sensory lab and home environment. Participants evaluate the products at pre-, during (at home) and post-exposure and follow-up.
Participants’ liking for the plant-based granola increased significantly over the exposure period (p = 0.003), suggesting that repeated consumption promoted familiarity and appreciation. Liking for the insect-based pasta also increased (p = 0.021), indicating that incorporating insect ingredients into familiar formats may reduce initial resistance. In contrast, liking for the insect-based bar decreased over time (p = 0.030), highlighting the importance of sensory and consumer evaluation on food formulation.
Qualitative comments indicated that improved acceptance was associated with familiarity and balanced sensory attributes, while negative reactions were mainly related to texture, flavour intensity and expectations regarding insect ingredients. Ethnographic observations based on meal photographs showed that participants frequently combined the products with vegetables, carbohydrates and sauces, adapting them to familiar meal structures.
Overall, combining quantitative, qualitative and ethnographic data provided a comprehensive understanding of how consumers interact with the products, highlighting the role of repeated exposure, sensory characteristics and consumption context for sustainable protein alternatives acceptance.
Acknowledgements
This work has received funding from “Agenda Mobilizadora InsectERA – um novo setor bioindustrial”, funded by the Resilience and Recuperation Program in Portugal, financed by the Next generation EU funds. Author Barbosa acknowledges Non-Academic Doctoral grant No. 2023.03467.BDANA, funded by the Foundation for Science and Technology (FCT) and supported by Sense Test, Lda. Authors Barbosa, Rocha, Ribeiro and Cunha acknowledge additional support from FCT through UID 05748: GreenUPorto - Centro de Investigação em Produção Agroalimentar Sustentável.
Bruna Barbosa1,2,3, Célia Rocha1,2*, Daniela Campelo1,3, José Ribeiro2, Rui Costa Lima1, Luís Miguel Cunha2*
1Sense Test, Vila Nova de Gaia, Portugal
2GreenUPorto, Faculty of Sciences, University of Porto, Porto, Portugal
3Faculty of Nutrition and Food Sciences, University of Porto, Porto, Portugal
*celia.rocha@sensetest.pt
Publish date 2026-03-27
Author(s) Bruna Barbosa1,2,3, Célia Rocha1,2*, Daniela Campelo1,3, José Ribeiro2, Rui Costa Lima1, Luís Miguel Cunha2*
