We have the decoder ring for your next trip to the supermarket.

Have you ever wondered about all of those codes on the food that you buy? What do those numbers and letters mean? Do they have serious significance? Should I be paying attention to these? Do they even make a difference? The answer to all of these questions is yes, if you want to be an informed consumer.

Why are bread bag Kwik Loks and twist ties different colors?

Bread isn't delivered to stores every day of the week, it's really only delivered five days a week: Mondays, Tuesdays, Thursdays, Fridays and Saturdays. Each of those days has a color associated with is. Traditionally, Mondays are blue; Tuesdays are green; Thursdays are red; Fridays are white; Saturdays are yellow. Those colors are on the twist ties or the little plastic bag closures (called Kwik Loks) and therefore reflect the day that your bread was baked.

So the next time you're shopping for bread, note what day of the week it is and look for the color closest to that day of the week.

Incidentally, Kwik Loks are also used for produce, in the medical industry, and more. In fact, the apple producers were the first to use Kwik Loks.

How fresh are those eggs?

The stamp on the end of the egg box will tell you everything you need to know.

On my box of Happy Egg Company eggs that I bought on Friday Oct 22 the stamp looks like this:

  • P1267 15 JKF

  • SELL BY NOV O5 2021

  • 280 18:03

Let's break that down:

  • P1267 | This is the plant number (look it up here). This is Mid-States Specialty Eggs in Berryville, Arkansas. These eggs have traveled farther than we have in the past year, and after looking at the farm's website, those hens don't seem all that happy. The 15 JKF is a mystery.

  • SELL BY NOV O5 2021 | Mr. Obvious is going to tell us that this is the sell-by date.

  • 280 18:03 | This is the Julian date and time that the eggs were packed. Day 280 is October 7 at 6:03PM. So the time between the packing and sell-by dates is 30 days.

How long should those eggs be okay to eat? The USDA says 3-5 weeks, but they don't specify whether that is from the packing date or the sell-by date. Eggs don't last that long in this house.

What do can codes mean?

Codes on canned goods are different for different manufacturers. The codes indicate batches, canning dates, and enable the tracking of product in interstate commerce. These codes also enable manufacturers to rotate their stock and locate their products in the event of a recall. The codes are not meant for the consumer to interpret but have a "Best if Used By" date. Discard cans that are dented, rusted, or swollen. High-acid canned foods (e.g. tomatoes and fruits) will keep their best quality for 12 to 18 months. Whereas, low-acid canned foods (e.g. meats and vegetables) will keep for two to five years.

Is it conventionally grown or organic?

When you're shopping for the best fruits and vegetables for your family, you might be interested in making sure that your fruits and vegetables are grown organically. Fortunately, you can get this information directly from the PLU – the number code for paying for your produce at the register. All you need to do is crack the code on the produce sticker.

  • Organic produce has a 5 digit PLU number that begins with the number 9.

  • Conventional produce has a 4 digit PLU number that begins with the number 4.

  • Genetically modified (GMO) produce has a 5 digit PLU number that begins with the number 8.

Unfortunately, this labeling isn't fail-proof, as some organically grown produce raised from GE or GMO seeds will still be labeled simply beginning with the digit 9, to indicate that is was grown organically.

If you want your produce at it's freshest, just ask someone in the store when they restock the produce section. On all military installations, it's on Mondays, but it varies by store everywhere else.

The whole food date labeling protocol in the United States could be improved. Check out this study done by Harvard in 2013: "The Dating Game: How Confusing Food Date Labels Lead to Food Waste in America"

Some things have improved since then, but not much. The best advice is to shop seasonally and shop local. California farmer's markets are as local as it gets. These people really care and are proud of what they grow and raise. And they have strict regulations that they have to follow. Check out our list of Farmers Markets on the West Side for information on when to shop and where.

Cecilie Korst/, supermarket, decoder, codes, egg carton stamp, upc codes on produce