I have experiencing a huge wave of fatigue/ tiredness after sauerkraut as well.. from my findings sauerkraut is high in Tryptophan: Tryptophan increases the production of serotonin, the neurotransmitter responsible for mood, sleep, and regulating bowel movements.
Consuming foods high in tryptophan causes a rise in insulin leaving you feeling drowsy after your meal.
Try removing sauerkraut and see if the problem goes away.