There are three possible methods of preparing a 3-1 solution: In method 1, amino acids and dextrose are mixed first. Fat emulsion is added next followed by the additives. In method 2, amino acids are added to the fat emulsion. Dextrose is added next followed by the additives. In method 3, dextrose, amino acids, and fat emulsion are added simultaneously while swirling and mixing. Additives are incorporated last.