Yeah, the taste is what keeps many people away from beets. Pickling is an interesting way to make it more palatable. I hadn’t thought of that, honestly. Pickling preserves and extends the shelf life of beets by either anaerobic fermentation in brine or immersion in vinegar. The pickling procedure may affect the nitrate content as has been shown in studies on pickled Asian foods such as Kimchi. In fact the nitrate content of the latter is quite high (>120mg/100g), too. And pickled beet has been shown to have in excess of 25 mg/100g of product. But that will depend on the beetroot cultivar that has been used. So it is difficult to say how much nitrate will be in any pickled beet product.
I’m not too much worried about the nitrate in preserved meat (nitrate and nitrite) as long as it is consumed together with whole plant foods. After all, the link between nitrate in processed meats and cardiovascular disease is very weak to start with (I’m working on a post to explain this in greater detail).