Successful baits rely on stimulating fish into feeding mode, even in the most difficult conditions. Many basic bait ingredients do this to some extent but often these baits are significantly enhanced by the addition of specific bait additives. The mechanisms and reasons for the success of these enhancers is poorly understood but the results are there for all to see.
To the human many of these enhancers seem totally bland and highly unattractive but to fish they are the compounds that signal food. Many of these compounds exist naturally in small quantities in certain foods. By including these additives we simply magnify the baits attraction by increasing the concentration of these stimulatory compounds. It is simple but can be highly effective.
Typically these additives must be included in baits at low levels. It is important not to exceed the recommended levels, too high an inclusion can often have the reverse effect and make the fish suspicious of the bait.