Cook the pasta in salted water until al dente. Rinse with cold water, pour some sunflower oil over it, allow to cool.
Transfer to a large bowl and sprinkle the mayonnaise on top. Chop the beetroot and add with the juice. Dice the feta cheese, add the peas and mix everything carefully. For caper lovers, these can also be added. Season to taste with pepper, salt, apple juice and vinegar.
If there is enough time, let it steep in the refrigerator for about 1 hour, then season again. Our vegetarian daughter thinks this is very tasty even without the tuna and the color is thrilling!