Changes

Dissolved oxygen meters play a large role in brewery QC of the final packaged products as well as oxygenation of wort pre-fermentation. Although cheaper DO meters can be used to find the PPM(parts per million) of oxygen in the wort pre-fermentation, more expensive advanced equipment is needed post fermentation as you'll need equipment that is capable of reading much lower levels of DOon a ppb level. When monitoring DO its crucial to be under 100 ppb packaged DO and for hop driven beers its ideal to be under 50 ppb or else you risk oxidation and other off flavors associated with oxygen.