Although advancements in science and technology have increased food production, there is still sever hunger in several parts of the world. Besides issues around access to nutritious food, there are other social, environmental, economic and health issues related to food production, distribution, consumption and discarding. Among these, food (in-)security and food waste tend to be significantly urgent problems. The complex socioenvironmental and technoscience issues that are related to food, food waste and food security place them among STSE and socioscientific issues. As much of these issues and problems are related to power imbalances in (global) food systems, participatory roles of citizens are required to bring more sustainable and equitable balances. To achieve that, critical food literacy and critical science literacy are much needed to support citizen engagement in informed sociopolitical actions to support food justice, societal change and environmental sustainability. In this research, and using an action-oriented science education framework, we collaborated with four community members (CMs) of immigrants as they learnt about, and acted upon, issues of food waste in a major metropolitan city in Ontario, Canada. In doing so, we explored their learning experiences, challenges that they encountered (as a minority group) in their ‘new’ socio-cultural contexts, and how these were relatively mitigated. Our research indicates that language, (science and) political literacies, and needs to negotiate collective formal identities were among main challenges that CMs encountered. Our research further points to significant roles of personal reflection, funds of knowledge, and dialogue in supporting CMs’ learning experience and co-production of knowledge, and needs for translation efforts to enhance these engagements. Implications are also discussed.