How have the courts in England and Wales dealt with the issue of unmerchantable hops?

An early case having a direct bearing on the question under consideration is Parkinson v. Lee (1802), 2 East 314. The facts were, I think, practically identical in principle with those of this case. The defendant had bought hops from a grower who had fraudulently dampened them to increase the weight, which made them unmerchantable. Without knowledge of this, the defendant resold them to the plaintiff, by sample fairly drawn from the bulk, at the fair market price of merchantable hops. The defect could not be detected by ordinary examination of the sample, and the defendant was held not liable, on the ground that he was not the grower, and there was no fraud.