What's Your Take on Expired Fish Food?

  • We are currently upgrading MFK. thanks! -neo
Wife = Cubic
Girlfriend = Real

I would definitely turn that around.

you're gf can't divorce you, take you for half, and make you pay alimony!
 
I have a number of things to say about expiration dates, but I will try to refrain from a rant...

In order to determine when food "expires," whatever that means, you would have to do an experiment. This means taking samples from a number of different batches; storing a large quantity of product in normal, abnormal, and ideal conditions; and then sending them to a lab regularly to get tested for whatever criteria you mean when you say expired. I say that no such test has ever been done. I know for a fact that it's not been done for many human drugs, and I can say without a doubt that it hasn't been done for fish food. The fact is that properly prepared and sealed items in an inert gas in a cool, dark place last more or less indefinitely (well, many years). The FDA also says that frozen food lasts indefinitely if stored at freezer temperatures, even if exposed to air. Except for, umm, freezer burn type changes.

Here are some things that I think you should consider. Open food and food in bright light is subject oxidation which will break down certain desirable components. I would not necessarily feed open, expired food, and I would try to use opened food as soon as possible. Additionally, products that sit for years on LFS shelves will be exposed to light. Not so good.

You can buy expired food if you are looking to save money. If you want a scientists opinion, look for food whose packaging looks the same as that of new packages (the inks/dyes will be a good indicator for you and they are subject to more harsh conditions than the contents). I would not buy it if it is not well sealed. Check this by squeezing and/or looking for a good seal. Some vitamins are unstable and their quantities will decrease with time. You can mix with "fresh" food or supplement with something like Vita-chem. However, my understanding of vita-chem is that we often are forced to feed predators foods with excess thiaminase (rosies, goldfish, krill, etc.) which do not replicate natural diet, and thiamin (and other B vitamins) may need to be supplemented. YMMV.
 
I have a number of things to say about expiration dates, but I will try to refrain from a rant...

In order to determine when food "expires," whatever that means, you would have to do an experiment. This means taking samples from a number of different batches; storing a large quantity of product in normal, abnormal, and ideal conditions; and then sending them to a lab regularly to get tested for whatever criteria you mean when you say expired. I say that no such test has ever been done. I know for a fact that it's not been done for many human drugs, and I can say without a doubt that it hasn't been done for fish food. The fact is that properly prepared and sealed items in an inert gas in a cool, dark place last more or less indefinitely (well, many years). The FDA also says that frozen food lasts indefinitely if stored at freezer temperatures, even if exposed to air. Except for, umm, freezer burn type changes.

Here are some things that I think you should consider. Open food and food in bright light is subject oxidation which will break down certain desirable components. I would not necessarily feed open, expired food, and I would try to use opened food as soon as possible. Additionally, products that sit for years on LFS shelves will be exposed to light. Not so good.

You can buy expired food if you are looking to save money. If you want a scientists opinion, look for food whose packaging looks the same as that of new packages (the inks/dyes will be a good indicator for you and they are subject to more harsh conditions than the contents). I would not buy it if it is not well sealed. Check this by squeezing and/or looking for a good seal. Some vitamins are unstable and their quantities will decrease with time. You can mix with "fresh" food or supplement with something like Vita-chem. However, my understanding of vita-chem is that we often are forced to feed predators foods with excess thiaminase (rosies, goldfish, krill, etc.) which do not replicate natural diet, and thiamin (and other B vitamins) may need to be supplemented. YMMV.

There are no industry recognized standards for shelf life. However, studies have been done and a reasonable estimate for the shelf life of dry pet foods (e.g. dog/cat kibble, fish pellets, etc) is 12-18 months, depending on the antioxidants used and storage conditions. Shelf life in the pet food industry is usually determined through chemical analysis of oxidation products, palatability testing, and olfaction (e.g. see reference below*). As you mentioned, the main cause of diminished shelf life in dry products is oxidation. This not only causes rancid odors and alters flavor reducing palatability, but also destroys essential fatty acids and the fat soluble vitamins A, D, E, and K potentially leading to malnutrition. I personally would rather err on the side of caution and stick with non-expired food. Unless you are feeding a huge amount of food, the price difference really isn't much, and if you end up having to supplement for the lost nutrients then you really are not saving anything and probably spending more time dealing with the supplements.

*Gross KL, Bollinger R, Thawnghmung P, et al. Effect of three different preservative systems on the stability of extruded dog food subjected to ambient and high temperature storage. Journal of Nutrition 1994; 124: 2638S-2642S.
 
To think that the aquatic industry, especially those that are involved in the manufacture of fish food, do not test at post production levels for nutrient loss, spoilage, mycotoxins, etc, is absurd.

There have been some generalizations made in this discussion as though all fish foods are created equally, when in fact they are not. As previously mentioned the fatty acid levels, moisture content, and level of antioxidents will all play a major role in how long a feed stuff will remain stable , which is where expiry or "best before" dates come in to play.

We know that feed ingredients with high levels of unsaturated fatty acids are susceptible to becoming rancid over time, and cereal grains exposed to high moisture content (over 12-14%) can become prone to mold and possibly aflatoxins.

http://www.soyaqua.org/pdf2/asafeedhandstorepub.pdf

http://edis.ifas.ufl.edu/fa095

As mentioned in the first link freezing ones food will not necessarily make it last indefinitely, either. Again, one cannot generalize on the stability or oxidation rate of a food stuff without knowing a number of factors, such as freezing temp, lipid levels, antioxident levels, and even the types of antioxidents utilized by the manufacturer.

Certainly not all foods require being tossed the moment they reach a manufaturers expiry or best before date, but with some of the high fat, high moisture content foods that are currently on the market spoilage is only a matter of time, even IF they are stored under ideal conditions. (such as a dark, dry, cool environment)

For both palatability reasons, and cost effectiveness, most manufacturers would love nothing more than to add 25% or more moisture content to their fish food, but by doing so manufacturers & feed mills also realize that the stability (ie shelf life) of the food will be decreased by a significant amount. Add to that less than ideal storage & handling conditions by a feed mill, a retail store, or by consumers, and you now have a recipe for disaster.

12-18 months from date of manufacture is a good starting point, many fish foods will remain stable with little overall nutrient loss for much longer (3-4 yrs), while others should be used up within 6 months time, or less, depending on storage & handling practices.

The bottom line is there are way too many factors involved to give the OP a simple yay or nay on the products that he was considering.
 
I have related questions to ask : 1) how long will my New Life Spectrum food be good after the opening date; 2) Is it a good idea to freeze it if I have a big quantity; 3) How long will it stay good once frozen ?
 
Impossible to answer with any real accuracy without specifics, just as it is impossible to answer the OP's question other than in a general manner.

For best results ALL fish food should be stored in a dark, dry, cool environment, and fed within the manufacturers stated expiry date, or in lieu of that within 1 year of purchase.
 
I probably wouldn't buy it already expired, but if I had some that expired I wouldn't hesitate to feed it to my fish. Heck, I've had stuff out of my fridge that was way expired; if it hasn't grown turf on it and smells ok, I'm throwing it on the grill!
 
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