It’s hard to get universal ripening of your grapes in a small vineyard with lots of variability. The Wizard provides some pointers as well as clues to determining grape ripeness when the refractometer is left home. Plus, the threat of contamination from “killer” yeast.
Oxidation is one of the most common faults among homemade wines. The Wiz has some tips for minimizing exposure during racking along with advice for how to read fermentation temperature, reducing reductive stink with copper, and carbonating a dessert wine.