I find that the fish oil imported from Chile smells unpleasant. I was provided with a sample of this fish oil as Exhibit MX-3 and have smelt it. It smells like a cross between stale fish and vinyl. My associate thinks it smells like semi-fermented grass cuttings revealing his more sophisticated nose. I have not tasted it but I am prepared to infer that it would be very unpleasant to consume even in small doses. I also accept that placing the fish oil in the soft-gel capsules has the effect of making palatable and flavourless a product which is essentially very unpleasant. It has another benefit too. By sealing the fish oil in the capsules the speed of oxidation is reduced and, along with that, the rate of deterioration in the fish oil caused by exposure to light. This is not the case with the liquid fish oil imported from Chile.

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There is a related issue. Professor Barrow properly drew my attention to the phenomenon of ‘burp-back’. ‘Burp-back’ occurs when a soft-gel capsule containing something malodorous such as fish oil is consumed. Once the capsule descends into the digestive depths of the stomach the soft-gel dissolves releasing its noxious payload the odour of which, thus liberated, rises up the gullet to the mouth where, unsought and unwelcome, it presents itself as a salutary warning against the perils of belching. Professor Barrow succinctly described it as ‘unpleasant fishy burping’. Just because the soft-gel fails in the inhospitable regions of the upper reaches of the alimentary canal does not mean that for many people the capsule is not effective to protect them from the smell of the fish oil. It does mean, however, that it cannot be entirely correct to say that encapsulation has changed the nature of the fish oil so that its odour is no longer present. It can be present when the fish oil is extracted from the capsules and it may emerge if a consumer should burp.