Pure amino acids in their powder form. This is the amino blend we use in our bait. It is a very expensive product, but also very strong. Do not over do it. You only need a little to get the powder out of it. This is a mix of a few secrets, plus DMPT, L-Lysine, Cysteine, Arginine, L-Proline, Alanine, Glutamine, Aspartic Acid and Glutamic Acid. 
Testing have shown some incredible results. Use one of our liquids/dips as a wet dip and use the Amino powder after that so it sticks to the hookbait.