Mushroom by-products as ingredients for food applications: A review of health and sustainability benefits

Mushrooms are renowned for their nutritional and therapeutic potential, playing a crucial role globally in the culinary and pharmaceutical industries since ancient times. However, increasing production and consumption of mushrooms have also led to a rise in mushroom waste, which includes deformed mushrooms, caps, stems, and spent mushroom substrate (SMS) that contains bioactive compounds having nutraceutical and therapeutic properties. Despite having multiple health benefits, these by-products have traditionally been considered waste. Hence, incorporating them into food formulations will reduce waste, promote sustainability, and enhance the nutritional value of formulated foods. The online databases, including Google Scholar, PubMed, online market research, ScienceDirect, Web of Science, and Scopus, were screened using keywords such as caps, stems, spent mushroom substrate, mycelium, and off-grade mushrooms. This review outlines a comprehensive analysis of the nutritional composition, extraction methods, and bioactivity of mushroom by-products, as well as their applications as functional ingredients in various food products. The review highlights the potential of mushroom by-products to enhance food system resilience, improve public health, and reduce agro-industrial waste. The novelty of this review lies in integrating the compositional, nutritional, and environmental perspectives of mushroom waste valorization. Additionally, utilizing mushroom waste aligns with the United Nations Sustainable Development Goals by supporting waste reduction while promoting the emerging global trend towards a circular economy. • Increase in production of mushroom has led to a rise in their by-products. • Potential utilization of mushroom by-products as food ingredients is reviewed. • Utilizing mushroom by-products aligns with sustainable development goals.