Sparging is a well-established practice in fermentation: by introducing bubbles into the liquid, the process increases the surface area for interaction between the gas and the liquid, making fermentation more efficient.
However, by using ultrafine or nano bubbles, such as those produced by Hydrosome Labs’ technology, there is massive scope to improve on this process.
“The bubbles produced by our technology are around 50 to 100 nanometers in size. To put this in perspective, we can fit a trillion of our bubbles inside a champagne bubble and, being so small, they have a tremendous surface area to interact with cells,” Bob Jacobs, president of Hydrosome Labs, told this publication.
This high surface-to-volume ratio, along with a slight negative charge on the outer surface of the bubbles, maximises their interactions with cells, so they are able to deliver active ingredients to cells more efficiently.
“They can transport large payloads of nutrients and compounds to cells and living organisms. This unique delivery system improves growth rates by increasing the efficiency with which the ‘hungry’ cells receive essential nutrients and compounds,” said Jacobs.
“The other thing that’s important to note is that these bubbles do not float. They stay in the solution rather than rising to the surface and escaping which means they have a lot more time to interact with the cells,” he added.
Hydrosyme Lab’s nano bubbles: Small bubbles, big benefits
In a preliminary evaluation at the Integrated Bioprocessing Research Laboratory (IBRL) at the University of Illinois Urbana-Champaign, the ultrafine bubbles produced by Hydrosome’s technology showed an immediate benefit to microbial growth.
Substituting Hydrosome H2O for regular water in a precision fermentation process doubled the cell reproduction rate, doubled the yields, and reduced fermentation time by 25%, according to Hydrosome.
In a real-life scenario this could overcome some of the obstacles that are currently thwarting the growth of the precision fermented food industry.
“The [precision fermentation] industry is exploding and there’s a lot of demand for fermentation capacity. This is a big problem as companies can’t build tanks fast enough, which is why they are trying to squeeze more capacity out of their existing infrastructure. Our process has been shown to double the output of a fermentation process and reduce in the order of 25% the time it takes to do a fermentation,” said Jacobs.
He continued: “That obviously has implications for cost as well, which is important as there are some segments of the precision fermentation industry that are still not cost competitive when compared with their conventionally manufactured counterparts.”
A further benefit is that the Hydrosome technology is more energy efficient than existing bubbling methods, said Jacobs.
“Bubbling gases through the fermentation and mixing and agitating fermentations uses a lot of energy. Our process uses significantly less and achieves better results,” he said.
Ultrafine bubbles: Replicating a process from nature
Asked to describe Hydrosome’s process for producing ultrafine bubbles, Jacobs said that essentially, it was replicating a process from nature.
“Ultrafine bubbles were first discovered in the 1980s in crashing ocean waves and flowing rivers. We have just found a way to produce them in a more structured way,” he said.
Hydrosome uses a technique called hydrodynamic cavitation, Jacobs explained.
“It is basically spinning the water under very high pressure. We create a vacuum in the centre and when the water and the vacuum exit the process there are some proprietary physical parameters that create the bubbles in a specific way. There are no chemicals; it literally uses the same physical forces that are present in nature.”
One of Hydrosome’s points of difference versus other players in the ultrafine bubble space is that its bubbles remain intact in solution for more than a year. As well as being beneficial if a fermentation lasts a few days, this extended stability opens up new applications such as improving nutrient uptake in skincare and delivering enhanced, longer lasting hydration in performance drinks.
“There are so many different applications for this technology and I think we are only scratching the surface,” said Jacobs.
No nano concerns
Hydrosome deliberately uses the term ‘ultrafine’ rather than ‘nano’ to distance its technology from any nano concerns. However, given that these are bubbles, rather than plastics or particles, Jacobs said that the company hadn’t experienced any anti-nano pushback.
“They are bubbles, and as such, they go away over long periods of time. When you change the phase of the liquid that the bubbles are in, if the water is boiled or evaporated, for example, they are destroyed. So, it is not like they are an issue for the environment.”
As a commercial product, Hydrosome’s technology takes the form of a skid that can be hooked up to a fermenter, allowing companies to improve the output of their fermentation process using their existing infrastructure. The ultrafine bubble generation unit is leased rather than purchased, eliminating the need for capital outlay.
“We charge a lease based on the use of the equipment. That leasing cost is a fraction of the total savings customers will make from improving their process,” noted Jacobs.
