Influencer Efficacy and the Fan Effect in Green Food Branding: The Mediating Role of Perceived Quality

Social media has become the core channel through which people communicate, and the important role of influencer marketing in creating a fan base for brands is widely recognized. Grounded in Source Credibility, Homophily Theory and Signaling Theory, the purpose of this study is to investigate how influencer efficacy affects the fan effect of green food brands under digital social media. This paper adopts a quantitative research method. A cross-sectional survey was conducted on the Wenjuanxing platform and collected 417 valid responses from consumers who had previously purchased green food based on an influencer’s recommendation. A conceptual model was tested through the structural equation modelling procedure. The results showed that professionalism (β = 0.166, p = 0.011), trustworthiness (β = 0.291, p < 0.001), and similarity (β = 0.267, p < 0.001) had positive effects on perceived quality. Furthermore, perceived quality (β = 0.333, p < 0.001) significantly promoted the formation of the brand fan effect and partially mediated the effects of these characteristics of influencers on the brand fan effect. This study provides new insight into the fan effect of green food brands and also provides a theoretical basis for green food companies to accurately match their brands with suitable influencers, enhance the brand fan effect, and rationally formulate operational strategies.