I don't know of any "literature" that can direct you on how to create lot codes for a "product" you use internally.
That being said the lot code only HAS to be something that you can identify to be a specific quantity of product. You can make it anything you want insomuch as it makes sense to you and that you can use it later to identify the product.
Using the date is a fine thing to do and we use that where I are for the most part.
So for example let's say your company is Mr. Incognito's Doughnut Factory. For the dough you could use MIDFD06262014 which you know stands for Mr. Incognito's Doughnut Factory Dough and the date. It doesn't have to be that and it doesn't have to be that long... but it could be.
I've worked in a place that had 2 factories. In an effort to obfuscate the lot code they used a Julian date calendar but added something like 300 to it. Before the date they had a 2 letter code for the factory. So let's say my doughnut factory is in Detroit it might have been something like this DT4024 Detroit (DT), 102 day of the year (402 - 300), in 2014 (4).
For the dough it's going to be used internally so your code date probably could be just the date it was made. "The dough that made Mr. I's fantastic chocolate chip cookie was code date 62614" Then you can go to the dough paperwork for 6/26/14 and see what ingredients went into it.
Any ingredient you use that is purchased form a supplier the lot code should be the one they use and provide you with. That way you don't have to cross reference it. So Setanta provides Mr. I's factory with sugar with a lot code of 01234 that's what I would write on my paperwork.
Please keep asking questions if you have any of them. No question is a dumb question and I want to make sure all of your questions are answered.