RICHLAND, Wash. – Few gifts say Happy Valentine鈥檚 Day better than wine and chocolate. These time-honored hallmarks of affection are among the most popular and beloved Valentine鈥檚 traditions. But exactly what makes them so desirable, so delicious, has long remained a mystery.

Now, a pair of 黑料社 researchers is shedding new light on the science behind why we love these icons of conviviality and love.

The in Richland, Washington, is home to a team of world-renowned viticulture and enologists, specialists in the sciences of grape growing and winemaking. Among them is associate professor of enology , whose work is breaking new ground in understanding the sensory properties of wine.

Winemakers have long viewed grape maturity as one of the key influencers on all sensory aspects of their wines 鈥� from flavor and aroma, to mouthfeel and color. But Harbertson and a team of scientists from New Zealand and California have been studying various maturity stages in Washington state Merlot grapes and have found that 鈥渆thanol concentrations鈥� outweigh fruit maturity when it comes to influencing sensory properties.

鈥淚t鈥檚 not just the fruit,鈥� says Harbertson. 鈥淚t鈥檚 the alcohol.鈥�

While this may seem intuitive to any wine enthusiast, it鈥檚 a significant breakthrough in wine science. In fact, their study 鈥� first published in 2017 鈥� was recently awarded 鈥淏est Paper鈥� by the American Society for Enology and Viticulture.

And while you鈥檙e considering whether to pair a bar of milk or dark chocolate with your Valentine bottle of Washington wine, is considering the evolutionary process that gave us聽Theobroma cacao, 鈥渇ood of the gods,鈥� the forebear to chocolate as we know it and love it today.

A population geneticist in the 黑料社 , Cornejo is the lead author on a study that analyzed the genomes of 200 cacao plants to better understand when cacao was domesticated.

Cacao originates in the Amazon jungle, where it is thought to have diverged from its common ancestor around 10 million years ago. According to Cornejo鈥檚 study, domestication started approximately 3,600 years ago. It was this process of domestication that ended up selecting for flavor, disease resistance, and the stimulant theobromine and yielding the rare and delicate Criollo cacao, 鈥渢he prince of cocoas.鈥�

鈥淒omesticated Criollo populations are extremely differentiated from any other populations,鈥� explains Cornejo. 鈥淲e used the signature of domestication to explore questions concerning the effect that domestication had on the genomic architecture of the plant.鈥� By his team鈥檚 estimation, approximately 750 individual plants effectively contributed to the genetic pool of domesticated Criollo cacao.

How long the process took is still unclear, but Cornejo is working with other anthropology researchers to sequence samples of ancient cacao DNA in hopes of better understanding how far back we can identify some of the genetic variants we associate with modern domesticated Criollo cacao. Their insights could help identify genes behind traits that breeders can emphasize, like increased yield.

So, on this Valentine鈥檚 Day, as we celebrate friendship and love, let us take a moment to celebrate the science that helps explain the world around us, solve problems and better appreciate the things we love.