From Waste to Taste: My PhD Journey in Transforming Food Waste into Novel Fermented Foods

By Anik Khan

During my high school days, I have always been fascinated by how microorganisms manage to thrive everywhere. During my bachelor’s degree in pharmaceutical sciences, I initially envisioned a career in the pharmaceutical industry, focusing on the formulation of various medicines. Then I had a turning point when I worked on an undergraduate research project on chromium-resistant bacteria and their antimicrobial drug resistance mechanisms. I felt a spark and discovered my affinity for microbiology. 

During my MSc, I chose to work in microbiology and explored the lignocellulosic biomass-degrading microbial communities in landfill sites. I was amazed to see how the complex microbial community functions, and how it could be harnessed to transform landfill waste into something valuable like biofuels. This work intensified my interest in understanding different microbial communities and how their functions can be tailored to solve real-world problems.  

Today, as a PhD student in food microbiology, I am studying microbial communities from traditional fermented foods and trying to figure out how these communities can be tailored to develop novel fermented foods. 

From waste to taste: developing novel fermented foods

Food fermentation is one of the oldest technologies humans have been using around the world for millennia. This technique provides humans with a wide range of gastronomic, cultural, health, and scientific benefits. Foods and beverages like cheese, sauerkraut, kimchi, yogurt, kefir, beer, and wine are just a few examples of the remarkable power of fermentation.

My PhD project is being funded as part of a larger EU-funded project named DOMINO. My PhD project aims to develop a novel, healthy, and sustainable plant-based fermented beverage. The idea of novel fermented food has emerged as a response to several converging factors, including an increase in demand for diverse and functional fermented foods, an increase in interest in health and nutrition, efforts to find novel solutions to global food shortages, and the shift towards more sustainable and plant-based diets (Arrigan et al., 2024). One of the promising ways to develop novel fermented food is switching substrates in traditional fermented foods with food waste or by-products that we normally discard but still contain valuable nutrients, such as fruit pulp and brewers’ spent grains. This can allow the transformation of food waste into nutritious food products.

However, scaling up this novel fermentation is challenging due to the lack of defined starter cultures. Here comes the synthetic ecology approach, I am using for my PhD project to rationally design synthetic microbial communities that are tailored to enhance flavour, nutrition, and functionality of these novel fermented foods (Jin et al., 2024). For instance, certain lactic acid bacteria such as, Lactobacillus plantarum, are known to enhance the flavour and nutritional attributes of fermented foods by producing organic acids and other bioactive substances (Lin et al., 2025). Similarly, yeast like Saccharomyces cerevisiae can enhance the flavour by producing esters, fatty acids, and other volatile compounds during the fermentation (Que et al., 2024).

Tackling food insecurity with novel fermented foods

The global food system is already under pressure. According to the report of the World Food Program (2025), around 343 million people across the world are facing acute food insecurity (World Food Programme (WFP), 2024). This food insecurity will likely intensify in the future as the global population is projected to reach 9.8 billion by 2050. The food production must increase by 70% by 2050 to ensure food security for this growing population (Roy et al., 2024).

A significant amount of food byproducts is generated every year, particularly from fruit and vegetable processing. The growing production of fruit juices leads to the generation of more byproducts and waste. For example, pineapple, banana, grapes, oranges, blueberries, strawberries, and mango processing produce peels, pomace, seeds, and pulp, and they are often unutilised. However, these byproducts are packed with soluble and insoluble fibres, vitamins, minerals, antioxidants, and polyphenols (Torres-León et al., 2018). Conversely, breweries in Europe generate over 3 million tonnes of brewers' spent grains annually, and they are currently used as cattle feed (Qazanfarzadeh et al., 2023). However, brewers' spent grains are a nutrient-rich byproduct containing dietary fibre, protein, and bioactive compounds like phenolic acids, which can offer numerous health benefits if transformed into food products (Virdi et al., 2025).

Novel fermentation provides an innovative solution to utilise these food by-products and transform them into healthy food products. Imagine the microbial transformation of fruit pulp leftovers into a healthy fermented beverage or spread, and brewers' spent grain into high-protein snacks. By producing these novel fermented foods, we can tackle food insecurity and build a more sustainable food system.

References

Arrigan, D., Kothe, C.I., Oliverio, A., Evans, J.D., Wolfe, B.E., 2024. Novel fermentations integrate traditional practice and rational design of fermented-food microbiomes. Curr. Biol. 34, R1094–R1108. https://doi.org/10.1016/j.cub.2024.09.047

Jin, R., Song, J., Liu, C., Lin, R., Liang, D., Aweya, J.J., Weng, W., Zhu, L., Shang, J., Yang, S., 2024. Synthetic microbial communities: Novel strategies to enhance the quality of traditional fermented foods. Compr. Rev. Food Sci. Food Saf. 23, e13388. https://doi.org/10.1111/1541-4337.13388

Lin, M., Lin, S., He, H., Yu, Y., Hu, J., Zhou, L., 2025. Lactiplantibacillus plantarum in fermented beverages: Properties, mechanisms, and future prospects. J. Funct. Foods 129, 106864. https://doi.org/10.1016/j.jff.2025.106864

Qazanfarzadeh, Z., Ganesan, A.R., Mariniello, L., Conterno, L., Kumaravel, V., 2023. Valorization of brewer’s spent grain for sustainable food packaging. J. Clean. Prod. 385, 135726. https://doi.org/10.1016/j.jclepro.2022.135726

Que, Z., Wang, S., Wei, M., Fang, Y., Ma, T., Wang, X., Sun, X., 2024. The powerful function of Saccharomyces cerevisiae in food science and other fields: a critical review. Food Innov. Adv. 3, 167–180. https://doi.org/10.48130/fia-0024-0016

Roy, A., Moradkhani, H., Mekonnen, M., Moftakhari, H., Magliocca, N., 2024. Towards strategic interventions for global food security in 2050. Sci. Total Environ. 954, 176811. https://doi.org/10.1016/j.scitotenv.2024.176811

Torres-León, C., Ramírez-Guzman, N., Londoño-Hernandez, L., Martinez-Medina, G.A., Díaz-Herrera, R., Navarro-Macias, V., Alvarez-Pérez, O.B., Picazo, B., Villarreal-Vázquez, M., Ascacio-Valdes, J., Aguilar, C.N., 2018. Food Waste and Byproducts: An Opportunity to Minimize Malnutrition and Hunger in Developing Countries. Front. Sustain. Food Syst. 2, 52. https://doi.org/10.3389/fsufs.2018.00052

Virdi, A.S., Mahajan, A., Devraj, M., Sanghi, R., 2025. Brewers’ spent grains: Techno-functional challenges and opportunity in the valorization for food products. LWT 227, 117785. https://doi.org/10.1016/j.lwt.2025.117785

World Food Programme (WFP), 2024. WFP 2025 Global Outlook. https://doi.org/10.71958/WFP129881