In spite of the fact that increasing numbers of food processing companies are moving to open dating it is not yet universal. For those products that do not come with a plain "best used by" date it is still possible, albeit with much more difficulty, to determine the rotation period for that specific product.
For a processor to move their product in interstate commerce it must exhibit a packing code. This allows them to easily track their product for purposes of stock rotation and in the event of a recall. These packing codes are usually a series of letters and numbers that indicate dates, times, and sometimes places of manufacture. These dates are not "use by" dates, but the time the container was actually filled. As they are not really intended for general public knowledge these codes are frequently unique to a particular processor and are not commonly published by them.
It is possible to get the keys to these codes by contacting the processor and asking how to decipher the dating code for specific product lines. Over time, readers have been doing this and the code keys below are the ones that have been sent to me. Obviously, they are only a few of the many, many products that use closed dating and I hope that future readers will continue to send these codes in as they are gleaned from the processors.
Frankly, when it comes to the potential dozens of products that would require deciphering their packing codes the entire process is a major nuisance. While it is better to have an encoded date than not to have one at all, it would be far better if processors would just use clear open dating and (best used by) so we wouldn't have to carry a book of code keys like covert agents every time we go to the grocery. Should you happen to call a processor customer service number you might tell them this in an effort to encourage them.
Before I list specific manufacturers there is one fairly widely used code key that may be useful. Some processors use a system where all the days of the year are listed 1-365 (366 for leap year) as the first three digits in the code. This number is then followed by a single letter such as "B" and then by a single digit that represents the year.
Some examples of this might be:
ARMOUR STAR CANNED MEAT PRODUCTS
Vienna Sausage, Stew, Chili, Deviled Ham, Potted Meat, Slice Dried Beef, Soups, etc. but does NOT include Armour Star Roast Beef or Corned Beef.
The code is on the bottom of the container. The first letter is the month of production; A=January, B=February, C=March and so on. The following two numbers represent the day of the month it was processed and the third number indicates the year.
Example: A code of B148C23 would be B=Feb, 14 = the fourteenth day, 8=1998. B148C23=February 14, 1998 and the last three characters would be plant or processing line locations.
Armour Star Microwaveable Meals have a two line production code on the container lid. The second line is the is date and uses the same code as above.
BERTOLLI OLIVE OIL
two years prior to the use by date on the bottle or can.
BUSH BROTHERS & CO.
Baked beans, chili, etc.
A five digit code on the bottom of the can. The first digit is the month, the next two digits is the day of the month, the next number is the year and the last digit is ignored.
Example: A code of 50173 deciphers to be:
5 = the fifth month or May
01 = the first day of May
7 = 1997
3 = last number is discarded.
Thus 50173 is May 1st, 1997.
CAMPBELL SOUPS: Best by date on cans. Filled exactly two years prior to that date.
DEL MONTE Canned fruits, vegetables, etc. I'm not sure if it applies to *all* product lines.
A five character packing code, usually on the bottom. The first character is a digit representing the year. The next three characters are digits representing the day of the year the product was packed. The last character is a letter and may be ignored.
Example: A packing code of 8045B deciphers to be:
8 = 1998
045 = The 45th day of the year or February 14th.
B = A plant code.
Thus 8045B is February 14th, 1998.
The manufacturing date is coded to their fiscal year that begins on June 1st and ends on May 31st.
Interpret the code as follows:
The first character of the code is a letter and represents the month the product was made.
The second character in the code is a number which represents the year the product was made.
The following two characters are numbers that represent the day of the month the product was made.
The remaining characters following identify plant location and shift information.
Example: A packing code of E731B would translate as follows:
E = October
7 = 1997
31 = 31st day of the month
B = A plant location
The following is their 12 month cycle. The letter "I" is not used because it can be confused with the number "1".
A = June E = October J = February
B = July F = November K = March
C = August G = December L = April
D = September H = January M = May
HANOVER FOODS CORP.
Small whole potatoes, green beans, corn, etc.
A five digit code on the bottom of the can. Omit the first digit. The next digit is the year. The remaining three digits are the day of the year the product was packed.
Example: A code of 28304 deciphers to be:
2 - discard this number
8 = 1998
304 = the 304th day of the year or October 31st
Thus 28304 is October 31st, 1998
First character is a number, second is a letter with the remaining characters being a lot ID. The number is the year it was packed with the letter being the month, October = A, November = B, December = C, January = D, and so on through the year. The recommended shelf life is 2 years.
Their packing code is a letter followed by five numbers. The letter is their plant location and the numbers are the dating code in a MM-DD-Y format.
Example: A code of G07048 decodes to mean:
G = plant location
07 = July
04 = The fourth day of the month
8 = 1998
The can was packed July 4, 1998 at plant location G.
JELL-O BRAND PUDDINGS & GELATINS
The first four digits are the date coding. The first digit is the year and the following three digits is the day of the year.
Example: A packing code of 804522 10:38 deciphers as:
8 = 1998
045 = the 45th day of the year or February 14th
22 = discard the last two digits.
10:38 = the time it was packed.
Thus 804522 10:38 means that box of pudding mix was packed on February 14th, 1998 at 10:38 a.m.
McCORMICK HERBS & SPICES:
There should be a four digit number of the bottom of the spice package or extract bottle. On foil packages, it will be around the outside edge. This code is more complicated than other manufacturers so read closely.
Example: Using a number 3604 as the packing code:
To derive the year, take the first number and add 5 (3 + 5 = 8) so 1998 is the year of manufacture.
To derive the month and day, divide the last three digits by 50 (604 / 50 = 6 with 4 remaining). The six indicates the last whole or complete month before the month of production, January, February, March, April, May, and then June. The next month, July, is the production month. The 4 remaining is the day it was produced.
Therefore a packing code of 3604 means that product was packed July 4, 1998.
While not as precise, you can save considerable time by just finding the year. The last three digits representing the day and month will increase as the year grows.
Canned soups, beans, etc.
Two lines of code on top of the can. The top line, the first two characters are the date portion. The first character is a letter indicating the month and the second character is a digit indicating the year.
Example: A packing code of L7N18 1211 (this is the first line) would be:
L = 12th month or December
7 = 1997
N18 = ignored
1211 = ignored.
Thus a packing code of L7N18 1211 indicates the can was packed in December of 1997.