The phrase "sterile conditions" refers to an extremely clean and germ-free environment where there are no harmful microbes or bacteria present. Full definition
It should be done under sterile conditions by a veterinarian familiar with breed standards. (thesprucepets.com)
In schools they have to plant seeds in sterile conditions only when the science curriculum says they may, and line up for meals which they have no hand in preparing. (home-ed.info)
As always, when working with food it is important to work clean but you won't need sterile conditions to create some delicious red cabbage sauerkraut. (thehealthytart.com)