Because surely you have some sauerkraut juice in the fridge?
I’m guessing “liquefy until glossy” means emulsify. I’ve heard of German recipes using sauerkraut juice in dressing.
From a box sold in Chicago, Illinois.
2 oz. sauerkraut juice
1 medium lemon (including skin)
1/2 tsp. salt
3-1/2 Tbsp. honey
1 cup oil
Liquefy all ingredients together except oil, then add oil slowly and liquefy until glossy.