Pellets The vitamin C in pellets is only active for 90 days

[saresare93]

So in a laboratory textbook (reference below), in the part on guinea pig nutrition, I found the following:

"If the vitamin C content in the food is insufficient (it remains active in pellets for only 90 days), ascorbic acid can be added to the drinking water (0.5 g/l)."

Has anyone else heard of vitamin C only lasting that long in pellets? The use-by dates on my pellet bags are far longer than 3 months.


Reference:
Kaiser, S., Krüger, C., & Sachser, N. (2010). The guinea pig. In R. Hubrecht & J. Kirkwood (Eds.), The UFAW Handbook on the Care and Management of Laboratory and Other Research Animals, 8th Edition (pp. 380-398). Wiley-Blackwell.

 

[scoottie]

We recommend never putting anything into the water

 

[saresare93]

We recommend never putting anything into the water

My post has nothing to do with putting things in the water - that was merely the end part of the quote. My post is about the pellets.

 

[scoottie]

"If the vitamin C content in the food is insufficient (it remains active in pellets for only 90 days), ascorbic acid can be added to the drinking water (0.5 g/l)."

But to answer the question I haven't heard of it or worried about it since I get pellets in a small quantities

 

[saresare93]

And your point in a quoting the textbook I quoted as though to somehow accuse me of saying something I didn't? Perhaps you could refer to where, at any point, I actually asked about stuff in the water? My post has absolutely nothing to do with water and nowhere did I say it was. The only mention of water was at the end of a textbook sentence which contained the relevant information about the pellets. So to clarify, this thread is only about the vitamin C lifespan in pellets, and not about stuff in the water.

 

[sallyvh]

How old is this textbook?

I would say that is dated/incorrect information.

High quality guinea pig pellets are now made with stabilized vitamin C, meaning it can last longer. Your book doesn't know the exact formulation of all current guinea pig pellets so it's just a generalized statement.

You can also used pellets past their expirary date, all it means is that the vitamins and minerals will start to degrade a certain point. Not that they are instantly bad or useless.

I know Oxbow pellets come with an expirary date on the bag, so if stored correctly the content analysis is guaranteed up until that date. Also with KMS pellets I believe the vitamin C is guaranteed for 225 days from the manufacturing date.

 

[saresare93]

How old is this textbook?
I would say that is dated/incorrect information.
High quality guinea pig pellets are now made with stabilized vitamin C, meaning it can last longer. Your book doesn't know the exact formulation of all current guinea pig pellets so it's just a generalized statement.
You can also used pellets past their expirary date, all it means is that the vitamins and minerals will start to degrade a certain point. Not that they are instantly bad or useless.
I know Oxbow pellets come with an expirary date on the bag, so if stored correctly the content analysis is guaranteed up until that date. Also with KMS pellets I believe the vitamin C is guaranteed for 225 days from the manufacturing date.

The textbook is only from 2010 - I have many older textbooks and take their information with a grain of salt because they're so old, but I was more struck by this one because it's the latest edition. Of course you're right in that they don't know the exact formulation of every pellet brand, so perhaps their statement is the case for the standard lab guinea pig pellets of Europe or something? Or perhaps they referenced an old textbook themselves.

Do you know how vitamin C is stabilised? I would be interested in reading about it.

 

[sallyvh]

I would say they used dated or just blatantly incorrect information.

I personally have no knowledge of the stabilization process of vitamin C. You'd have to research that one on your own!

 

[bpatters]

Stabilized vitamin C will last much longer than 90 days -- I think it's actually about 270 days.

Textbooks often repeat outdated information because the whole book isn't updated when one section needs to be. Guinea pigs don't get much research, so their information just gets copied over and over again. The list of bad information on guinea pigs in veterinary textbooks could fill a book itself.

 

[SonOfOdin]

cant hurt to keep in a dark cool area also

 

[saresare93]

Textbooks often repeat outdated information because the whole book isn't updated when one section needs to be. Guinea pigs don't get much research, so their information just gets copied over and over again. The list of bad information on guinea pigs in veterinary textbooks could fill a book itself.

Very frustrating. How am I supposed to know if a piece of information is accurate when I can't even trust the latest textbooks? (Not a serious question, just a rhetorical vent.) -_-
Guinea pigs get lots of research, just not with anything useful. It's generally things like 'what happens when we burn them with boiling water' and 'what happens when we inject their sperm into rabbit muscle.' Experimentation, yay.

cant hurt to keep in a dark cool area also

Yeah I do. I just bought a bulk 8-pack of pellets online so good to know it wasn't a waste, haha.

 

[saresare93]

Kaytee on their vitamin C stability:

As you are aware, vitamin C (ascorbic acid) is a vital nutrient for guinea pigs. The source of vitamin C generally used for Guinea Pig pellets is unstable and requires a much shorter code date on the product (6 to 9 months maximum). Vitamin C is generally used as a coated product that is somewhat more stable then the plain ascorbic acid. This coated product is sometimes referred to as "stabilized". The primary value of this form is that it does a good job of protecting the product during storage, prior to processing. When ascorbic acid products are subjected to heat during pelleting of the product, there is significant loss due to the heat processing, and then the ascorbic acid remaining in the product begins to breakdown due to interactions between feed ingredients, oxygen, light and moisture. In typical conditions, approximately 50% of the products ascorbic acid is lost every 3 months. Therefore to adequately provide a 3 month shelf-life, 400 ppm of vitamin C should be present at manufacturing. Likewise, to ensure a 6 month shelf-life, the product must originally contain 800 ppm to make sure the requirement of 200 ppm is satisfied after 6 months.
To avoid the uncertainty related to this issue of ascorbic acid unstability, especially considering how critical this nutrient is to guinea pigs and how quickly deficiency signs will be manifested, we are now using an ascorbic acid derivative called L-Ascorbyl-2-Polyphosphate. This is a newer, modified form of ascorbic acid that is both time and heat stable, enabling us to guarantee that the vitamin is available in the food for a far longer period. Kaytee did extensive feeding studies in guinea pigs to evaluate both the effectiveness and stability of this unique form and found that its performance (and stability) was far greater and more reliable than the typically used, and far less expensive, form of vitamin C.

Oxbow has L-Ascorbyl-2-Monophosphate instead of Polyphosphate. However, according to Argent Laboratories, it is the '2' part that stabilises the vitamin C.

The phosphate esters of vitamin C have L-ascorbate molar activity equivalent to L-ascorbic acid. Esterification of the 2-carbon atom protects vitamin C from destruction by oxidation.

So that's interesting. The more you know. ^_^

References:

Guinea Lynx. (2001). Stabilized Vitamin C in Kaytee Products. Retrieved from https://www.guinealynx.info/kaytee.html.
Argent Labs. (?). Stay-C V Stabilized Vitamin C. Retrieved from (broken link removed).