Stem Inclusion in Cabernet Franc Fermentations (2016)

Cabernet Franc Grapes were hand harvested and then destemmed into three lots. The first lot contained no stems, the second lot had 5% stems included based on fruit weight, and the third lot had 10% stems included based on fruit weight (ie: 1 pound of stems for every 10 pounds of fruit in the 10% inclusion treatment). All other treatments between lots were the same. Phenolic and color profiles were not gathered for the 5% treatment. Additionally, because the 5% inclusion did not complete malolactic conversion, it was excluded from tastings. 10% stem inclusion did not result in many chemical differences between wines. Monomeric anthocyanins, quercetin, malvidin glucoside, and total anthocyanins were increased by stem inclusion, whereas tannin was decreased. This increase in anthocyanin, however, did not greatly alter color intensity, possibly due in part to the decrease in polymeric pigment. Overall, these wines were not found to be significantly different from each other. There were slight trends for the stem inclusion to increase Bitterness and Herbaceous/Green character, and reduce Body. This study should be repeated over several vintages, as well as with different grape varieties in order to better determine the full impact of stem inclusion with Virginia ripening conditions. Additionally, this would be an interesting project to see how the wine evolves over time, to see if differences grow over time.

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