The Lavelin site says that a 5 gram pack of yeast for every 5 or 6 gallons of wine should be added to fermentation. But what I am not sure of is how to measure how many gallons I've crushed in order to add this amount. For instance, if I crush 15 lugs (36lbs) of sangiovese how many gallons is this? I know that 1 lug yields about 2 to 2.5 gallons of wine but that is finished product. The amount at the point of crush is obviously higher. So how much would 15 or 20 lugs require? Any calculation/formula? Thanks!