Frequently Asked Questions (FAQ)

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What is Chlorella?

Chlorella is a green, single-celled freshwater algae and was discovered in 1890 by the Dutch microbiologist M.W. Beijerinck. Chlorella belongs to the microalgae. It grows in large quantities in rivers and lakes in Southeast Asia. The green colour is obtained through the amount of chlorophyll present. This green pigment has a detoxifying and liver-protective effect. There are various types of Chlorella, but the most common types used in food supplements are Chlorella vulgaris and Chlorella pyrenoidosa.

What is the difference between macroalgae and microalgae?

The term “algae” includes both macroalgae and microalgae. Macroalgae – popularly called seaweed – can be observed with the naked eye. Examples are nori (sushi rolls) and sea lettuce. Microalgae are single-celled organisms up to 50 micrometres in size and therefore not or hardly visible to the naked eye. There are many different types of microalgae, the best known of which are Chlorella and Spirulina.

What are the main differences between Spirulina and Chlorella?

Spirulina and Chlorella are both rich in healthy nutrients. The differences between Spirulina and Chlorella are:

  • The blue-green Spirulina is a cyano bacteria and the green Chlorella is a freshwater algae
  • Spirulina has a helix structure, Chlorella consists of single round cells
  • Chlorella can be cultivated in a bioreactor, for Spirulina this is not possible (yet)
  • Chlorella generally contains more chlorophyll and is thus a strong detoxifier
  • Spirulina generally contains more proteins
  • Chlorella generally contains more cartenoids
  • Spirulina contains phycocyanin, a powerful antioxidant
What is the difference between Chlorella Vulgaris and Chlorella Pyrenoidosa?

There are many types of Chlorella, the best known being Chlorella vulgaris and Chlorella pyrenoidosa. Both are full of essential nutrients. Many properties can be greatly influenced by the cultivation method and origin of the algae. These things ultimately make more of a difference than the specific species.

Why is Chlorella good for people?

Chlorella is full of healthy nutrients. For example, it contains more than 20 different vitamins and minerals. Chlorella contains beta-carotene, depending on the cultivation conditions. This is a provitamin that is converted by the body into vitamin A. It plays an important role in the cell renewal process and has antioxidant properties. In addition, Chlorella contains many healthy fats and the green alga has several vitamin B variants. Chlorella also contains all essential amino acids, chlorophyll, dietary fibre, cartenoids, minerals and vitamin C, E and K. 

Why does Duplaco cultivate Chlorella algae?

There is currently a transition from conventional foodstuffs to alternative, sustainable and nutritious foodstuffs. We believe that Duplaco® micro-algae comply with these aspects and can also be used in vega(n) products. We therefore want to play a part in this transition, so that young and old will still have access to healthy food in the future.

Why did Duplaco choose to cultivate Chlorella pyrenoidosa specifically?

After a specific selection procedure, we chose a particular strain of Chlorella pyrenoidosa that is able to meet the desired nutritional values but that also grows well in our heterotrophic cultivation system: the algae achieves a high growth rate and a high concentration, so that we only need a slight centrifuging step after which we can immediately spray dry to a powder.

How are Chlorella algae cultivated by Duplaco?

Duplaco® cultivates in a heterotrophic manner. It has chosen to do so for various reasons. The autotrophic cultivation methods require a lot of downstream processing and are not profitable for large-scale production in the Netherlands due to the costs and the few hours of sunshine. Because of these and other (quality and sustainability) considerations, Duplaco® cultivates its algae in a heterotrophic manner. This enables us to produce a lot of algae in a small area with relatively low energy consumption. The amount of water we need to use is also very low compared to other production methods. Finally, there is the possibility of switching to residual flows in due course in order to make the process even more sustainable.

What is the difference between autotrophic and heterotrophic cultivation?

In autotrophic culture:

  • Sun- or UV light provides the energy source.
  • Mostly in Asia, from where large quantities of micro-algae are imported to the EU.
  • Advantage: no need to add food such as sugar. 
  • Disadvantage: algae is subject to fluctuations in quality due to fluctuations in sunlight and other conditions. Lower concentrations are reached because the light cannot penetrate through the upper layer of algae.
  • Grow in open ‘ponds’: risk of contamination (like heavy metals) or contamination from outside. 
  • Grow in photobioreactor systems: often fed with sugar as well because of slurry build up in the pipes, very expensive pipe systems or flat panel systems.

In heterotrophic culture:

  • Sugar provides the energy source.
  • Less volume and surface required
  • Controlled and sterile environment: no outside contamination.
  • Because sunlight is not necessary, this method can easily take place in countries like the Netherlands.
  • More possibilities to use alternative nutrients (eg residual flows).
  • Our heterotrophic Chlorella has a predominantly mild taste-odor profile.
  • The heterotrophic methodology of Duplaco®️ has a unique high conversion rate and growth rate, also in comparison to other conventional heterotrophic methodologies. In other words, a very efficient and productive methodology.
  • The heterotrophic methodology of Duplaco®️ results in a liquid with 10% dry matter, which is up to five times higher compared to conventional heterotrophic methodologies. As a result, we need less energy to get from liquid to powder by means of a centrifuge and a dryer. That is not only more sustainable, but also much more cost effective.
What does the Chlorella cultivation process look like?

The process of cultivating Chlorella begins with the mother strain from the laboratory. This is then fed into a 15 litre fermenter, which starts with a low concentration of microalgae. The concentration then increases to 100 grams per litre, or 10 percent dry matter. Then the culture goes into the large 10,000 litre fermenter. This is normal fermentation, but the settings of the fermenter have been optimised for algae.

When the fermenter is ready, the Chlorella is transferred to a cooling tank under overpressure, which serves as a buffer tank. After the first cooling tank, there is a centrifuge where the concentration is increased to 20 per cent, and then to the second cooling tank. 

From 20 per cent onwards, the solution goes to a standard spray dryer and eventually comes out as powder. This is one of the end products, alongside the fresh Chlorella (10% and 20%). The fresh Chlorella is tapped directly from the fermenter.

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