What DC should I use for someone trying to survive solely with an alchemy jug as their source of food and water?

They have no other access to sustenance or magic. There are no negative environmental effects beyond the complete lack of food/water in the surroundings.

The jug provides one of the following quantities of liquid per day:
\begin{array}{c|c} \text{Liquid} & \text{Max Amount} \ \hline \text{Acid} & \text{8 ounces} \ \text{Basic poison} & \text{1/2 ounces} \ \text{Beer} & \text{4 gallons} \ \text{Honey} & \text{1 gallon} \ \text{Mayonnaise} & \text{2 gallons} \ \text{Oil} & \text{1 quart} \ \text{Vinegar} & \text{2 gallons} \ \text{Water, fresh} & \text{8 gallons} \ \text{Water, salt} & \text{12 gallons} \ \text{Wine} & \text{1 gallon} \ \end{array}