The Pine Nut Mystery

"Pine Mouth," a metallic taste that consumers feel after consumption of pine nuts, has been an unsolved mystery until recently. Researchers in Journal of Agricultural and Food Chemistry found that many of the pine nuts on the market contain Chinese pine, a pine nut not usually consumed by humans. As there has been growing demand for pine nuts worldwide, manufacturers have been adulterating the product with cheaper, readily available pine nuts that are not fit for human consumption.

While the researchers cannot accurately pinpoint that the adulteration is to blame for "pine mouth," it is certainly the best hypothesis to date since the decade-old mystery started.

Pine mouth is described as appearing one to two days after eating pine nuts and lasting for one to two weeks.