Alexander Dyce, A General Glossary to Shakespeare's Works

bastard — “Drink brown and white,” MEASURE FOR MEASURE, iii. 2. 3 ; “Score a pint of bastard,” 1 HENRY IV., ii. 4. 25 ; “your brown bastard is your only drink,” 1 HENRY IV., ii. 4. 70. Bastard was a sweetish wine (approaching to the muscadel wine in flavour, and perhaps made from a bastard species of muscadine grape), which was brought from some of the countries bordering the Mediterranean. There were two sorts, white and brown. See Henderson'sHistory of Ancient and Modern Wines, pp. 290-1.