The chocolate eating Weevil beetle.

[xraanswerban]

My brother has a large chocolate museum with easter eggs and chocolates going back into the 1800s, he has an infestation of a chocolate eating weevil beetle that also eats it's way through the paper wrappers, can anyone help please?

[theprof]

First of all, are you sure they are weevils? You should be able to tell readily enough as the majority of weevils have a rostrum or snout sticking out from their head.

As to the treatment, I can give you some pointers which may be useful.

Normally, if the weevil infestation was not that bad, good hygiene and the gentle, frequent and thorough use of a vacuum cleaner would be about the only thing that might have some effect. All types of insecticide and insecticidal application methods are obviously out of the question. Pheromone traps are virtually useless against weevils although they are effective with some other insect pests - this is why I asked if you were certain they were weevils.

As far as I can see, that leaves only one option.

Bearing in mind, that chocolate is a foodstuff, the ideal solution is something called Controlled Atmosphere Technology.

In CAT, all your brother's chocolate would be removed, weighed and placed in a gas-tight vault or tent. The vault is flooded with a gas or mixture of gasses which might include Nitrogen and/or Carbon Dioxide and left for a specific period specified by the operators. The weight is necessary in order for the volume of gas to be calculated.

At the end of the period - it could be weeks or months - the vault is opened and all stages of the infestation will have perished.

Be warned - this procedure doesn't come cheap. Nevertheless, it seems to be the standard method used in the food industry and commerce.

We've used the idea ourselves on a smaller scale in the insect labs in uni and it does work.