The microbial food revolution

Abstract

Our current food system relies on unsustainable practices, which often fail to provide healthy diets to a growing population. Therefore, there is an urgent demand for new sustainable nutrition sources and processes. Microorganisms have gained attention as a new food source solution, due to their low carbon footprint, low reliance on land, water and seasonal variations coupled with a favourable nutritional profile. Furthermore, with the emergence and use of new tools, specifically in synthetic biology, the uses of microorganisms have expanded showing great potential to fulfil many of our dietary needs. In this review, we look at the different applications of microorganisms in food, and examine the history, state-of-the-art and potential to disrupt current foods systems. We cover both the use of microbes to produce whole foods out of their biomass and as cell factories to make highly functional and nutritional ingredients. The technical, economical, and societal limitations are also discussed together with the current and future perspectives.

Fig. 1. Timeline of the role of microbes in food.

A view of the various applications that rely on microbial processes. State-of-the-art in each process is explained as well as the current or potential role of genetic engineering and other future developments to enhance the process or use.

Fig. 2. Nutritional profile of microbes.

The left panel shows the various components of microorganisms that are beneficiary for nutritional needs. This includes both macro-molecular elements such as proteins and fibre as well as small bioactive compounds. The right panel shows the relative levels of fibre, protein and micronutrients in four groups of microorganisms commonly used for food applications based on comparisons from the review by Ravindra.

Fig. 3. The future of microorganisms in food.

A schematic showing the obstacles and future developments in the path to adopting widespread use of Microbial foods. In the beige circle the main obstacles are shown, including the economic viability of some processes, the consumer acceptance of some products, especially GMOs and, in some cases, the presence of undesired molecules. Future developments, shown in the blue arrow, aim to improve microbial-based foods and overcome these obstacles, and include producing nutritionally complete whole foods, alternatives to animal products (meat, dairy, eggs), and ingredients (like flavours or nutraceuticals) that can be made in an affordable and sustainable way, perhaps using waste or CO₂ as carbon sources.