Introduction
Seafood products, including mussels, play an important role in food consumption in Europe, especially in Italy (EUMOFA, 2024). In mussel aquaculture, reducing the use of conventional plastics in farming equipment, particularly in nets used during mussel growth, has become an important sustainability challenge (Arantzamendi et al., 2023; Baini et al., 2024). Since many production characteristics of seafood products are not directly observable to consumers, purchasing decisions may also depend on non-visible attributes and external information cues (Carlucci et al., 2015; Cantillo et al., 2021). It remains an open empirical question whether consumers recognise and value these innovations and whether regulatory support for sustainable materials affects their purchasing decisions (Oliva et al., 2019). This study investigates consumer preferences for farmed mussels produced with alternative net materials and tests the role of a regulatory requirement for the use of sustainable materials in mussel farming nets, within the LIFE MUSCLES project (LIFE20 ENV/IT/000570).
Materials and Methods
This exploratory case study analyses consumer preferences for farmed mussels produced with alternative net materials through a Choice Experiment grounded in Random Utility Theory (McFadden, 1974; Louviere et al., 2000). Data were collected in Italy through an online questionnaire distributed via non-probability sampling, yielding 242 completed responses. The questionnaire covered consumption habits, purchasing drivers, sustainability perceptions, label use, and sociodemographic characteristics. Choice tasks required respondents to select among alternatives differing in three attributes: net material (plastic, recycled plastic, bioplastic), the presence or absence of a regulatory requirement mandating a minimum share of sustainable materials in mussel farming nets, and price premiums expressed in ���/kg. The regulatory attribute was included to test whether an external institutional requirement linked to otherwise non-observable production practices may influence consumer choice. A no-purchase option was also included to approximate realistic decision contexts (Train, 2009). In addition, the questionnaire included a Van Westendorp Price Sensitivity Meter (PSM) (Van Westendorp, 1976) to explore respondents' perceptions of an acceptable price range for the innovative mussel farming concept as a whole. While the choice experiment was used to estimate trade-offs among specific attributes, the PSM provided complementary evidence on perceived price acceptability.
Results
Results from the choice models show that the sustainability-related attributes are positively associated with the probability of choosing a mussel alternative. In particular, in the conditional logit specifications, both recycled plastic and bioplastic nets display positive and statistically significant coefficients relative to conventional plastic, with the effect of bioplastic being the largest among the product attributes considered. The presence of a regulatory requirement for a minimum share of sustainable materials in mussel farming nets is also associated with a positive and statistically significant effect on choice. By contrast, the price coefficient does not show a stable and robustly interpretable negative sign across specifications. This result suggests caution in deriving direct willingness-to-pay estimates from the choice experiment alone and, more generally, indicates that the monetary dimension is not cleanly identified within the tested price range.
The latent class model points to heterogeneity in preferences across respondents, although these class profiles should be interpreted cautiously given the exploratory nature of the study and the sample size. The three-class solution highlights a larger main group (about 69% of respondents) and two smaller groups (about 17% and 15%), suggesting that respondents differ in the strength and direction of their response to sustainability-related attributes. Additional evidence from the Van Westendorp Price Sensitivity Meter indicates an optimal price point of about ���4.85/kg for the innovative mussel farming concept, compared with a reference market price of about ���3/kg. This result should be interpreted prudently, as the PSM captures stated price perceptions rather than observed choices; however, it suggests that the price levels used in the choice experiment may have fallen within a relatively acceptable range for many respondents.
Discussion and Conclusion
For this exploratory case study, the results indicate that respondents tend to prefer mussel alternatives associated with more sustainable net materials, especially bioplastic, and they also respond positively to the presence of a regulatory requirement for sustainable materials in farming nets. These findings are consistent with the idea that non-visible production attributes may matter in consumers' evaluations, although the underlying mechanism cannot be identified directly from the present data.
At the same time, the price attribute does not show a stable and robustly interpretable negative effect across the choice model specifications. This limits the possibility of deriving direct willingness-to-pay estimates from the choice experiment alone and suggests caution in interpreting the monetary dimension of preferences within the tested price range.
In this respect, the Van Westendorp Price Sensitivity Meter provides a useful complementary perspective. Although it captures stated price perceptions rather than observed trade-offs, it identifies an optimal price point of about ���4.85/kg, above the reference market price of about ���3/kg. Taken together, these results suggest that the surveyed respondents show interest in sustainable mussel farming innovations, while the price dimension requires more careful investigation in future studies based on broader samples and refined price designs.
Acknowledgment
This study was developed within the LIFE MUSCLES project (LIFE20 ENV/IT/000570) (https://lifemuscles.eu/en/il-progetto/)
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