Course Blog Projects Course 2018

Nurture – Growing meals at home

The food production problems society faces

The state of global food production is changing rapidly. Our team is attempting to envision how the state of our food may look in 10 – 20 years time and discovering the problems we may face.  As the atmospheric temperature levels rise many negative and unforeseen consequences, and many are outlined below in a U.S. report on the state of agriculture:

“Even under the most optimistic CO2 emission scenarios, important changes in sea level, regional and super-regional temperatures, and precipitation patterns will have profound effects. Management of water resources will become more challenging. Increased incidence of disturbances such as forest fires, insect outbreaks, severe storms, and drought will command public attention and place increasing demands on management resources. Ecosystems are likely to be pushed increasingly into alternate states with the possible breakdown of traditional species relationships, such as pollinator/plant and predator/prey interactions, adding additional stresses and potential for system failures. Some agricultural and forest systems may experience near-term productivity increases, but over the long term, many such systems are likely to experience overall decreases in productivity that could result in economic losses [and] diminished ecosystem services” [1]

Breaking down the listed issues and focusing on the problem of more dramatic weather uncovers whole new sets of problems to solve. Take for example that the higher chance of extreme temperature shift “is expected to increase the exposure of food to certain pathogens and toxins. This will increase the risk of negative health impacts, but actual incidence of foodborne illness will depend on the efficacy of practices that safeguard food” [2] 

Lastly and most difficultly is the issue that high carbon dioxide levels are going to cause our food to contain less nutrients than they did before: “The nutritional value of agriculturally important food crops, such as wheat and rice, will decrease as rising levels of atmospheric carbon dioxide continue to reduce the concentrations of protein and essential minerals in most plant species” [2] When that is coupled with the issues of overfishing [3] and the highly unsustainable meat industry [4], neither of which may be sustainably viable in 10 years time, then we have a major issue to solve in the production of protein for human consumption. 

Our solution

Our solution the problem of protein is to encourage the cultivation of  Spirulina (Athrospira) [5], which in fact is a cyanobacteria but commonly known as a microalgae. This organism is considered earth’s oldest plant that dates back to 3.6 billion years ago. Spirulina is a photosynthetic organism that makes complex compounds such as proteins and carbohydrates. It is perfectly edible and thought of as the most nutritious concentrated food. The Spirulina has many vitamins, antioxidants, probiotics, phytonutrients, nutraceuticals and 60-70% protein content of its dry weight. The World Health Organization (WHO) names it ‘Mankind’s best health product’, and UNESCO sees that it is the most ideal food for tomorrow. We want people to be able to grow this at home along with regular vegetables. in this way they can have a great deal of control over their own food, and to an extent, remove themselves from what may be a highly problematic industrial food production system. Spirulina can be grown in a closed system such as a tubular photobioreactor that we think is a convenient way to use in a household, were it is less exposed to contamination.

Growth of algae in tubes

Hydroponic system

The most important part of this project is a hydroponic food production system. Hydroponic plant culture system has been successfully applied in many areas [6]. Compared with traditional soil agriculture, this technique allows us to do more specific control of the plant growth especially for indoor culture. The waste of this system mainly comes from culture media, which is rich in nutrient element and cause “red tide” pollution. “Red tide” caused by algae in water could compete O2 with other organism and produce toxic in water, leading to deterioration of water quality. To achieve maximum use of medium, plants have different requirement of nutrient element could be selected and form a plant series [7].

Hydroponic system

Coupling algae with hydroponic system

After the culture medium go through the plant hierarchy, there are some nutrients cannot be absorbed by plants but still cause water pollution. In this project, we plan to culture edible algae with the hydroponic waste. For example, spirulina, an edible algae, could grow under 18°C -38°C, with low sunlight requirement [8]. Recent study has proved that the nutrient in algae is the best for human. Algae is high in lipids, such as oleic acid, DHA, are important in human health [9]. Another advantage of using waste medium is that waste medium has relatively lower nitrogen where the algae will be stressed to produce more lipid [8]. Natural products from algae are expensive to synthesis by chemical method and very low in other plant. However, the algae cultivation will be influenced by the plant hydroponic system; some research has coupled algae with different hydroponic plants [9], proving that hydroponic plants could influence algae quality. We are going to carry out some experiment to test which algae species to use and how efficiency the algae culture is. In the future, we might be able to generate algae with special functions or tests by controlling the growth condition.

Digestion of waste food and example cyanobacteria

Sunlight as another key factor to be considered

Since sunlight is very limited indoors, the utilisation of sunlight should be very efficient in the system. A possible solution is a vertical culture system. In our system, the plants are allocated at different positions for their different light requirement. Generally, when we arrange the plant hierarchy, we need to consider both sunlight and nutrient factors. EDIS website give use some growth requirement for common plant species [10].

Making the algae appetising

As we are looking to replace meat fish and many vegetarian sources of protein with algae we are well aware of how unappetising the raw materials may seem. We are looking 10 – 20 years into the future however and are fully expecting the ability of genetic modifiers to alter the taste of spirulina to come on leaps and bounds. It is important to us that the user should be able to cultivate different strains of the algae simultaneously so that they can have different flavours. One flavour that it’s already quite possible to induce is lemon flavour [11] and we would expand that out to include both sweet and savoury flavours which could more adequately fill the hole left behind by meat in the recipes we enjoy.


We are creating a new kind of eating and food preparation. Currently we are building a modular unit to contain our hydroponic and Spirulina growth system, and we are also creating recipes for how people would be able to cook with this new ingredient, which we are putting in a cook book

Cooking with spirulina and our cook-book


[1] CCSP (2008). The Effects of Climate Change on Agriculture, Land Resources, Water Resources, and Biodiversity in the United States. A Report by the U.S. Climate Change Science Program and the Subcommittee on Global Change Research. Backlund, P., A. Janetos, D. Schimel, J. Hatfield, K. Boote, P. Fay, L. Hahn, C. Izaurralde, B.A. Kimball, T. Mader, J. Morgan, D. Ort, W. Polley, A. Thomson, D. Wolfe, M. Ryan, S. Archer, R. Birdsey, C. Dahm, L. Heath, J. Hicke, D. Hollinger, T. Huxman, G. Okin, R. Oren, J. Randerson, W. Schlesinger, D. Lettenmaier, D. Major, L. Poff, S. Running, L. Hansen, D. Inouye, B.P. Kelly, L Meyerson, B. Peterson, and R. Shaw. U.S. Environmental Protection Agency, Washington, DC, USA.

[2] USGCRP (2014). Ziska, L., A. Crimmins, A. Auclair, S. DeGrasse, J.F. Garofalo, A.S. Khan, I. Loladze, A.A. Pérez de León, A. Showler, J. Thurston, and I. Walls, 2016: Ch. 7: Food Safety, Nutrition, and Distribution. The Impacts of Climate Change on Human Health in the United States: A Scientific Assessment. U.S. Global Change Research Program, Washington, DC, USA.

[3] Fox, B. (2018). Overfishing | Threats | WWF. [online] World Wildlife Fund. Available at: [Accessed 24 Apr. 2018].

[4] Walsh, B. (2018). The Triple Whopper Environmental Impact of Global Meat Production | [online] Available at: [Accessed 24 Apr. 2018].

[5] Soni, R., Sudhakar, K. and Rana, R. (2017). Spirulina – From growth to nutritional product: A review. Trends in Food Science & Technology, 69, pp.157-171.

[6] Barbosa, G., Gadelha, F., Kublik, N., Proctor, A., Reichelm, L., Weissinger, E., Wohlleb, G. and Halden, R. (2015). Comparison of Land, Water, and Energy Requirements of Lettuce Grown Using Hydroponic vs. Conventional Agricultural Methods. International Journal of Environmental Research and Public Health, 12(6), pp.6879-6891.

[7] Nguyen, N., McInturf, S. and Mendoza-Cózatl, D. (2016). Hydroponics: A Versatile System to Study Nutrient Allocation and Plant Responses to Nutrient Availability and Exposure to Toxic Elements.Journal of Visualized Experiments, (113).

[8] Estim, A., Saufie, S. and Mustafa, S. (2018). Water quality remediation using aquaponics sub-systems as biological and mechanical filters in aquaculture. Journal of Water Process Engineering.

[9] Eduardo, C C. Carlos, A C. Ana, T L. Maria, I L. Coupling microalgal cultures with hydroponics: prospection for clean biotechnology processes. J. Algal Biomass Utln. 2015, 6 (1): 88- 94

[10] Natalie B. Parkell, a. (2018). HS1279/HS1279: Leafy Greens in Hydroponics and Protected Culture for Florida. [online] Available at: [Accessed 22 Mar. 2018].

[11] Bouwmeester, H., Gershenzon, J., Konings, M. and Croteau, R. (1998). Biosynthesis of the Monoterpenes Limonene and Carvone in the Fruit of Caraway. Plant Physiology, 117(3), pp.901-912.