Spirulina

The research of Professor Benoit Guieysse bridges environmental microbiology and environmental biotech (design, modelling and scale-up of environmental bioprocesses).  A long time interest has been in algae with a substantial research focus on algae as a fossil fuel alternative, and for wastewater treatment.

Not convinced from his modelling that high production of an algae-based alternative fuel could be environmentally friendly, Benoit turned his attention to other possible commercial possibilities for growing micro-algae in New Zealand. The temperate New Zealand climate is ideal for algae cultivation, with 10 out of 12 months of the year providing good growing conditions.

Benoit was aware of spirulina but it was a casual enquiry while he was in France that brought the ‘superfood’ into sharp focus. During a visit to an algae farm he enquired about a dryer they were building, and he was surprised to discover it was being made for a local spirulina farm and that there were hundreds of spirulina farms in France.

Spirulina is a ‘superfood’ rich in B vitamins as well as vital minerals including magnesium, phosphorus, calcium and zinc. One heaped teaspoon of spirulina powder delivers 6 milligrams of natural iron, which is over 50% of the average adult’s recommended daily intake. And strictly speaking spirulina is a cyanobacteria as opposed to a micro-algae. There are 4 species that are used for commercial cultivation.

After crunching the numbers, Professor Benoit Guieysse decided spirulina would be an ‘easy’ product with which to develop an algae cultivation industry here in New Zealand. Bringing in fellow founding shareholders and directors Rob Lawler, Olivier Ausseil and Justin Hall, NZ Algae Innovations Ltd was registered in 2017.

NZ Algae Innovations set up spirulina cultivation at Himatangi Beach in the Manawatū. A starter culture was imported. Import permissions were aided by evidence in a 1960’s academic paper that showed their particular strain of cyanobacteria was already present in New Zealand. Benoit says clearing food safety and cultivation hurdles was a little more nuanced for this ‘novel food’ that bridges the horticulture and aquaculture industries.

Within a few years the team had gone through a number of iterations of their ponds and processing system as they refined the operation. Presently they have 2 shallow ponds under greenhouses. 4 containers provide the drying, grinding and packaging areas for their powder – Tahi Spirulina. Benoit acknowledges they need more ponds not only for production scale up, but to increase resilience, as algae cultures do occasionally collapse.

NZ Algae Innovations has been awarded a $500,000 grant by MPI’s Sustainable Food & Fibre Futures fund to assess the viability of larger scale production and investigate scaling up systems and processes from the present 400m² production unit, to a commercial pilot 6000 m². The company focus is on spirulina, but is also investigating other algae cultivars for applications such as food industry pigments and cosmetics. 

NZ Algae Innovations Ltd currently operates the only spirulina farm in New Zealand, under the Tahi Spirulina brand. The company uses a cultivation method based on the French artisan model. It utilises small covered ponds and dries the spirulina at low temperatures to assure a nutritionally dense end product. (Standard commercial production seen in large scale operations elsewhere has significant drawbacks through the use of very large open-air ponds, and spray-driers to produce the spirulina powder.  Open-air cultivation can result in contamination, such as bird droppings, and spray-driers require operation at temperatures that reduce the nutritional profile of the end product.)

Key to growing spirulina is water, air (CO²) and sunlight. Spirulina cyanobacteria produces its own food by photosynthesis, supplementing this with minerals from the water. Eschewing the fish based food of many commercial operations (because of flavour contamination), Tahi Spirulina adds a mix of minerals to the water. A rotating paddle system keeps the ponds aerated, and the greenhouse covering reduces evaporation while assuring environmental contaminants are kept out. The growing conditions and regular monitoring create an environment that makes pathogenic contamination unlikely.

Harvesting is by hand and starts with pumping the water and algae through a vibrating filter to separate out the algae slurry from the water. Water is then returned to the ponds. The slurry is pressed further until it resembles a ‘playdoh’ texture. Using an adapted sausage stuffer the ‘dough’ is extruded into long noodles for drying.

The dried noodles are then broken up to produce Tahi Spirulina Crunchies and finely ground to produce their powder. The tablets are produced off site at a third party facility.  

Just how easy is it to grow algae and produce spirulina? Benoit keeps things pretty close to his chest, but says the bigger challenge is in increasing production capacity — scaling up the artisan model they’re committed to.

Tahi Spirulina is looking at other spirulina products — recently a blended blackcurrant and spirulina powder was added to their selection. The company presently sells online and is stocked at a number of boutique outlets and Moore Wilson, most notably the products retail on the online Healthpost platform. Right now they’re selling all of their product and increasing capacity will be key — Benoit calls it a “grow or go” stage.

https://www.tahispirulina.co.nz/

https://www.opportunitygrowshere.nz/

Showdown Productions Ltd.   Rural Delivery Series 16 2021