Soon after he came to the OU, Rabbi Chaim Loike became troubled by the following problem: one of his companies sells totes of kosher glycerin as well as totes of non-kosher glycerin. When a customer of theirs requests more kosher glycerin, the customer gets a new tote of kosher glycerin. A non-kosher customer has it easier: the company sends a trailer tanker of glycerin to its various customers and fills up the totes with non-kosher glycerin, cutting out the need for new totes and reducing freight costs.
How do we know, asked Rabbi Loike, that the non-kosher glycerin is not being delivered to kosher glycerin totes? What can be done to prevent that possibility?
The only genuine solution (short of having hashgacha temidis on the use of the tote) is to rely on OU mashgichim to do an accounting. In our case, the mashgiach at the company receiving kosher glycerin in totes should be checking bills of lading to ensure that all new glycerin is coming in with new totes. A glycerin receipt through a tanker trailer would be a red flag!
The mashgiach should take a second step and see whether the amount of kosher glycerin received equals the amount of glycerin used in kosher production.
A careful records accounting provides a window to operations that simply can’t beviewed by simply walking through a warehouse (even though a walk-through is also essential).
Of course, these measures are necessary in any environment in which glycerin is used, whether the glycerin is kept in totes, drums, or storage tanks. And a mashgiach should be doing this kind of accounting with other sensitive ingredients, such as drums of kosher wine, as well.
Rav Belsky, shlita, has recently urged us to emphasize the importance of a documents review.
Do not be reluctant to ask experienced mashgichim to help! There are many on the OU staff who are very familiar with ingredients accounting procedures whose job description includes helping other mashgichim.