Africans Brought Rice to the New World

Genetic markers suggest African slaves brought the best rice strains to America.

Origins of Chocolate Lie in Preclassic Mesoamerican Beer

Analysis of Early Preclassic pots from Puerto Escondido in the Ulua Valley of Honduras show that chocolate was a by-product of the fermentation of cacao pods for use in making beer. The exploitation of chocolate as a specific product may date to ca. 1100 BC. It is noteworthy that this evidence is not from the Olmec Gulf Coast, but from the southern edge of Mesoamerica. Previously, the Olmec had been credited with the invention of chocolate, in part on linguistic grounds.

Early 16th Century Beads in Georgia May be Evidence of Failed Spanish Settlement

A handful of beads and metal found in southern Georgia (US) date to the early sixteenth century, and may have something to do either with deSoto's entrada in 1540, or an earlier failed settlement in 1526.

Edit: Looks like they're leaning towards De Soto