Your question is confusing. Do you mean "preservative" such as an ingredient that will prevent the chocolate from going bad? Chocolate has a fairly long shelf life due to the fact that is contains very little water which is necessary for spoilage bacteria and molds to form. So, unless you plan on storing your chocolate for a very long time, you do not need to add any preservatives.
Dear Friends ! Happy Morning. I am bar chocolate manufacturer in small scale . I make both with cocoa butter and vegetable fat.Now I wish to go marketing with bit big scale so I need to use preservatives. So if you have any idea to use it .Please kindly do let me know.
As others have said, pure chocolate (a.k.a. couveture) needs no preservatives because it contains very little water. Dark chocolate can be kept for well over 3 years IF it is stored between 18-24 Celsius. Milk and white chocolates can be kept for up to 18-24 months, but after this time the milk powder in the chocolate will go rancid.
If you are doing solid bars, there is no need for preservatives. If your bars have fillings, you need to look at the moisture content of the fillings before deciding on what kind of preservatives you want to use.
I can suggest a few good books in this subject if you are interested.
The first is Peter Grewing's "chocolates and confections", probably one of the best books I have, or have ever read on chocolate. The second is a series of books from Wybauw, in conjunction with Callebaut, in which he goes into great detail about various sugars (sorbitol, glycerol, etc.) and the effect they have on shelf life. These additives will prolong the shelf life, but as your fillings age, their flavor profile will change--and not for the better--regardless of shelf life.
From 2007-2016 I made and wholesaled a line of 26 varieties of chocolate bars, some with fillings, some with solid inclusions. The shelf life on these were anywhere from 12-18 Mths, and I achieved this using only natural ingredients, with absolutely no preservatives and only pure couveture--no compound chocolate.
I'll post the Ibn codes for the books I mentioned when I get home tonight.