Since then their use has become widespread with anglers suggesting anything up to 10ml per egg! You cannot read an article, a blog or see a DVD without somebody spouting off about their new wonder bait incorporation such and such oil.
This is strange, as anyone with a basic knowledge of chemistry will tell you that oils are insoluble and in their pure state they cannot be detected by carp, yet this fact is blissfully ignored by the majority of carp anglers.
Of course, there are several reasons why oils can be beneficial to carp and at the same time improve the bait, but using them as pure attractors is just plain daft, as carp do not possess a receptor that can detect oil. That said, carp can detect solids suspended in oil and carried into the water table by upward dispersion.
The best oils are also an important aspect of carp nutrition as they contain all the beneficial Omega fatty acids that carp use to maintain a healthy body weight and shape. It is now well accepted than you need to include a satisfactory amount of protein in a bait, and the same goes for fat. Fatty acids are as essential in their own way as amino acids. Both are a prime requirement in a balanced food bait and there is no better way of providing these vital fatty acids than in a bulk food oil.
Why food oil? Well, that is exactly what they are, food. Their make up has been structured to add balance to any well formulated base mix by increasing the amount of necessary dietary fat in the bait. Fat has a sparing action on protein thus allowing bait protein to be more widely assimilated into boosting healthy growth. Squid Liver Oil is rightly regarded as one of the richest sources of Omega-3 -6 & -9 EFAs along with amino acids and Gamma Linolenic Acid (GLA), which is also a rich source of Vitamin E.
At the same time oils provide the quickest and most easily converted source of energy and as nothing can survive without energy it figures that fats (oils) are as essential as any other factor in nutrition.
So which oils are the best for use in carp baits? Well it goes without saying that they should come from the group of oils know as polyunsaturated oils. These contain the important Omega -3 and -6 essential fatty acids which play an important part in the carp well-being. The prime examples are the fish oils, notably salmon oil, pilchard oil, squid liver oil, seed oils such as sesame seed and hemp seed oils, and blends of primarily fish oils.
I read a lot of twaddle about the need to generate a widespread oil slick on the surface over your bait, oil that has leached out of your bait carpet or PVA bag or mesh. Quite frankly this is a waste of time and if anything it could confuse and disrupt the process of chemoreception by which carp find their food. Carp do not recognise oil on the surface for what it is. They are not attracted to it per se as they do not possess a receptor capable of detecting it's presence. Hence the oil slick is virtually useless and by interfering with the olfactory process can actually do more harm than good!
OIL AS A DISPERSAL MEDIUM.
Now we come to the interesting bit. While carp cannot detect oils in isolation, they can detect food particles carried in suspension in oil.
You can speed up this process by pre-mixing known attractors with the oil you wish to use in you bait. These could be say, Green Lipped Mussel Extract, chilli powder, turmeric, liver powder, or Betaine Hcl, any solid attractor in fact that is not soluble in oil and can be detected by carp once in the water column.
I advise putting 75% of the oil into the bait itself using the remainder as a glug for your main feed (boilies).
Some emulsifiers work well with oils, others do not. Probably the most common (and the cheapest) is simple glycerine. Granular Lecithin is also very effective. I should also mention a surfactant (detergent) called Sodium Lauryl Sulphate. This certainly works in breaking down oil molecules but it has numerous health warnings against its use in products meant for human use and that alone is enough to rule it out for carp baits. In any case, while using an emulsifier will break down the structure of the oil, the end results is still insoluble, there are just more insoluble molecules than there were before, that's all! It does not make it any more attractive or detectable.
Want to beef up you PVA mesh parcels and at the same time slow down the rate at which the PVA melt? (Useful in hot water temperatures as this gives you time to adjust the position of the hookbait and its attached PVA mesh parcel if required.) Well simply dowse the pre-tied mesh parcels in a glug of an oil blended with a liquid food. Here the mesh parcels have been glugged in a blend of Nutrabaits Pure Salmon Oil and Trigga Liquid. Mmmmmmmmmmmmmmmm!