Slice the parsnips and add them to a saucepan with about 1 gallon of water. Bring the water to a boil and cook the parsnips for 10-15 minutes, until just tender but not mushy. Strain and reserve the cooking liquid, keeping the parsnips for another use.
In a separate saucepan, bring raisins to a boil with 1 quart of water and cook for about 5 minutes. Strain out the raisins for another use (like oatmeal), and reserve the cooking liquid.
Put the raisin waterback in a saucepan with the sugar and sliced lemon. Bring to a boil over high heat, and then reduce to a simmer. Simmer on low for about 45 minutes, until the sugar mixture starts to foam considerably as it changes to a syrup.
Remove the lemon slices from the syrup, and combine the raisin syrup and the parsnip water together. Allow the mixture to cool to room temperature, about 70 degrees.
While the mixture cools, bloom the packet of yeast by dissolving it in about 1/4 cup of water. Allow the yeast to stand until the parsnip syrup is at room temperature.
Pour the parsnip/syrup mixture into a primary fermentation vessel, and add the yeast, yeast nutrient and pectic enzyme.
Allow the mixture to ferment in primary for about 7 to 10 days, until the bulk of the fast fermentation has concluded.
Rack the wine into a secondary fermenter using a sterilized siphon and seal with a water lock. Allow the wine to ferment in secondary for about 6 months, until fermentation is complete and the wine has cleared.
Bottle the wine in wine bottles and cork. Store the wine for 6 months before drinking.