Often referred to as "black oil" or "green gold," pumpkin seed oil has a nutty taste and is packed with nutrients, including vitamin B1, B6, E, A and K. It's also a good source of magnesium, calcium and unsaturated fatty acid. The process of producing the oil is very tedious and time consuming. The average Halloween jack-o-lantern won't make the cut. Pumpkin seed oil is extracted from the seeds of the Styrian pumpkin, native to Austria, but also available in the US. These pumpkins are perfect for oil because the seeds lack the hard, stringy casing of other pumpkins.
Buy necessary Styrian pumpkins or seeds, or plan ahead by planting seeds in the spring and harvesting the Styrian pumpkins in the fall when ripened. Keep in mind that it will take approximately 2.5 kilograms of seeds to make one liter of oil. This is about five pumpkins.
Gather the seeds or, using a very sharp knife, split the pumpkins apart so that the seeds are exposed and the pumpkin can be cleaned out easily.
Remove all of the seeds, manually separating them from the pumpkin pulp.
Wash the seeds thoroughly and then allow them to dry completely. The seeds must be perfectly cleaned of all fibrous materials.
Roast the seeds at 140F for a few minutes in the oven. The amount of roasting and the temperature will have a great impact on the overall flavor of the oil. Be careful not to burn the seeds.
Press the seeds using a mortar and pestle to expel the dark oil. Apply firm pressure.
Collect the oil and allow it to rest in an airtight container for approximately four weeks. At this point, it can be bottled or canned.