In recent years, edible insects have gained global attention due to their nutritional and environmental advantages over conventional meat. While numerous species of edible insects are enjoyed in various cultures around the world, most Western consumers react with disgust and aversion towards eating creatures that are not regarded as food. The low consumer acceptance of this culturally inappropriate food is currently considered to be one of the key barriers to attaining the benefits of this potentially good source of food. This thesis thus investigates what determines the consumer acceptance of culturally inappropriate foods to provide insights into how insects may gain entry into Western diets. It extends the current body of literature that mostly focuses on the psychological determinants by giving more attention to the roles of culture, taste and product dimensions. The role of culture in determining acceptance was first explored using stage-wise focus group discussions (chapter 2) to examine how consumer perceptions and rationales differ across two cultural settings—one where insects are part of the local diet (Thailand), and one where insects are generally not regarded as food (The Netherlands). It was found that the key difference between those who accept versus reject insects as food lies in individual experiences. People from both cultures who lacked taste experience with a certain edible insect species were generally reluctant to eat it, where negative associations relating to the species and its appearances were only triggered when the food had not been eaten before. The cultural environment enables locals to accumulate rich experiences with obtaining, preparing and consuming the food. This resulted not only in Thai eaters gaining extensive knowledge regarding the taste and usage of available species, it also contributed to culture-specific preferences for certain species and products. The lack of cultural exposure therefore creates additional challenges for Dutch consumers to accept insects as food, where the unfamiliar taste, low availability, high price and lack of knowledge regarding its use remain barriers to acceptance. The role of taste in determining acceptance was investigated in the next chapters of the thesis (chapters 3 and 4). Through hedonic and descriptive sensory evaluations of beef burger patties claimed to contain unusual novel foods (i.e. lamb brain, frog meat, mealworms), the influence of the food’s identity (i.e. label) and properties (i.e. recipe) on acceptance were examined. In chapter 3, it was found that for culturally unusual foods like insects, the low willingness to eat was heavily influenced by its perceived inappropriateness as food. In chapter 4, descriptive sensory profiling revealed that Dutch consumers had little prior knowledge of the taste of the unusual novel foods and expected many negative attributes that were related to associations with the item (e.g. mealy mealworms, mushy lamb brains). After tasting, it was the properties of the food that mainly determined the taste experience. Although food appropriateness determined the willingness to eat, the food’s taste still plays a role in influencing food appropriateness. Together, chapters 3 and 4 conclude that introducing products containing unusual novel foods like insects could benefit from developing products that disconfirm the expected negative attributes that are associated with the novel food items, but the low food appropriateness means that other efforts are required to encourage repeated consumption. The role of product properties in determining acceptance was examined in the last two studies using systematically varied mealworm products (chapters 5 and 6). Chapter 5 showed that Dutch consumers had a strong preference for savoury products with ground mealworms despite their unfamiliarity with eating mealworms. Consequently they evaluated those products more positively in product appropriateness, expected sensory-liking, and willingness to buy and try, but even the most appropriate mealworm products were inferior to the original mealworm-free products. This poses difficulties when insect-based foods have to compete against existing products on the market. Food neophobia and demographic variables (e.g. age, gender, education level) were found to mainly affect the willingness to try. Chapter 6 showed that a more appropriate product improves the expected sensory-liking and willingness to buy mealworm products once and regularly, but this is only the case if consumers are already motivated to eat insects. Descriptive and ideal sensory profiling revealed that mealworm products were preferred to taste similar to the original products but were expected and experienced to taste different, which negatively impacted the experienced sensory-liking. While the taste experience was shown to play an important role in subsequent consumption intentions, willing consumers also shared that their intentions to regularly consume insect-based foods were still hindered by other practical and socio-cultural barriers (e.g. price, knowledge, availability, social acceptance). Overall, new insights from this thesis reveals the complex challenges faced in the consumer acceptance and product development of culturally new foods that are not only unfamiliar but also perceived to be inappropriate for consumption. It highlights the challenges that extend beyond the initial psychological barriers of consuming a novel food, and examines the cultural, taste, and product dimensions that need to be addressed when a new source of food is to be introduced into an existing diet. By focusing on the case of insects, we learned that to attain Western consumer acceptance, communicating the benefits of eating a food might help to raise interest but is insufficient to establish real consumption. Much more needs to be done not only in encouraging trial and changing consumer perceptions regarding the food’s qualities. There is a need to create a conducive environment that makes eating insects convenient, affordable, socially desirable, and enjoyable, as well as to keep in sight the original environmental goals when designing insect-based foods for Western consumers.