EPA (eicosapentasenoic acid), most commonly sourced from fish and seafood, is a long-chain omega-3 fatty acid much studied for its potential health benefits, especially for cardiovascular health.
Microencapsulated omega-3 ingredients are already used by the food and dietary supplements industry to prevent oxidation and deal with taste and odour issues associated with fish oils, but little research has been done in microencapsulation to boost bioavailability, the Hull team wrote in a paper published in the journal Lipids.
They set about investigating the potential of emptied-out pollen shells, known as exines, to be used as microencapsulation materials. Two of the researchers, Grahame Mackenzie and Professor Stephen Atkin, are involved in an enterprise spun out from the University of Hull called Sporodex, which provided the exines from Lycopodium clavatum, also known as club moss, for the study.
In the open-label study six healthy volunteers ingested 4.6g of fish oil with 20 percent EPA in the form of an ethyl ester, then as 1:1 microencapsulated powder of exines and fish oil.
The participants’ serum bioavailability was measured after each step. It was seen to be significantly higher with EPA from ethyl ester with exines than without exines.
Although the group was small, the researchers say the results are highly significant and warrant further in vitro and in vivo studies. At this stage the mechanism of action is not sure, but they hypothesise that it may be due to the “protective structure of fish oil-enriched exines whereby the whole unit could travel unhindered through the mucosal lining without releasing its inner core until it has entered the circulation”.
Sporodex’s exine technology is not currently available for commercial use, but Mackenzie told NutraIngredients.com that multinational companies are currently assessing the technology in their own laboratories, and others are looking at ways to scale up or provide companies with estimates of how much it would cost to produce the pollen on a commercial scale.
It is expected to be competitive with other forms of microencapsulation, however, and exines have the added advantage of having antioxidant capabilities of their own.
Mackenzie added that the cost would be lower if readily available pollens were used, such as rye or maize.
Flavour studies
The same team from Hull has previously reported on the use of exines to mask the flavour of fish oil in the journal LWT- Food Science and Technology.
They reported that the process of filling was simple, requiring no sophisticated equipment and as such is likely to be appropriate for scaling up to industrial quantities.
“A remarkable property of the loaded exines at 1/1 (w/w) was that they retained a free flowing powder consistency, potentially important for mixing in with other components,” they wrote.
Looking further ahead, the researchers also noted that enhanced flavour masking could be achieved by a double encapsulation with, for example, wax, or by using more traditional methods such as flavouring.
Source
Lipids
DOI: 10.1007/s11745-010-3427-y
Enhanced bioavailability of eicosapentaenoic acid from fish oil after encapsulation within plant spore exines as microcapsules.