Increase shelf life of marshmallows


I am not a food scientist so I’m looking for help as to why my marshmallows don’t last a minimum of 3 months.

a few factors:

I live in Melbourne, Australia where we have recently had both humid weather as well as damp and wet. We will not have any more humid weather for a while now.
I live 519m above sea level
I don’t want to use any artificial colours or preservatives
When making the fruit versions I am using freeze dried fruit powders
Packaged in Natureflex bags with minimal air but some

The vanilla flavour has the best texture after 4 weeks but smelt ‘off’. It was unfortunately stored in warmer than ideal conditions, but still dry. Approx average of 19-21C.

The fruit flavours have a crumbly like texture inside.

The mallows don’t ooze and are not wet in any way.

My most recent recipe vanilla: (Damp and cool day)

80g beef gelatin
400g water
900g dextrose
400g sugar
300g glucose syrup
400g invert sugar
300g water
8g salt
48g cornflour
80 g vanilla caviar

boiled to 113.6C (to take into consideration elevation of 1722ft, equation being 116C less 1.1C for every 1000ft).
Mixing in a 20L Standing Mixer and whipping until about 38C
About 10 minute total whipping, in 3 speeds

Fruit recipe is same as above however with 6g salt, 60g freeze dried strawberry powder and 40g vanilla extract (replacing the vanilla caviar)

Chocolate is same as vanilla however with 10g salt, 100g cocoa powder (added at whipping stage), 40g vanilla extract (replacing caviar), 6g instant coffee powder.

Thank you anyone and everyone for helping me.


Products with high sugar concentrate have long shelf life, generally.

But of course moisture content and also aw value of final product is very important.

And secondly, packaging material must protect the product from moisture and oxygen.

Can you specify the overall nature of your spoiled mallows .
Did you measure water activity ?

thank you for this. can i ask what you mean by ‘aw value’?

the packaging i’m using is home compostable as it is plant based. I have written their statement below:

With NatureFlex™, it’s possible to have packaging that is better for the earth, but can withstand the test of time when it comes to protecting your brand’s packaged snacks and dried foods. Our cellulose-based food packaging film delivers: A high oxygen barrier . Excellent grease resistance . * Protection against mineral oil contamination. * Light and durable materials. * Exceptional seal integrity for heat seal flow-wrap

thanks for the time you’ve taken to read and follow up my enquiry.

i really believe the storing temperature of the packaged items had a lot to do with the quality after time, as it was an unseasonably hot and humid summer when i was testing this recipe for shelf life.

however, the vanilla variant had the best texture it just ‘smelt off’, the fruit flavours (strawberry is one flavour, and apple is another) suffered the worst as they use freeze dried fruit which i believe re-absorbed the moisture however it was really a ‘crumbly’ texture inside that was the main issue, a slight dampness but not oozing.

the chocolate flavour (made with cocoa powder) was also crumbly but without the added moisture. same with the sesame variant.

i don’t use any food colouring drops or flavouring drops.

When you ask about measuring the water activity … I measure the water for the gelatin ratio, then i measure the water for the sugar syrup for boiling. Or do you mean to measure the liquid (or finished product) after cooking to gather how much moisture has evaporated? I have not done the latter on this recipe.


Aw is a symbol for water activity…You can read about it in the web and its importance in confectionery products shelf life, specially marshmallows.
it requires an instrument every institutional marshmallow manufacturer had it in their possession.
An example is this
Although there are less expensive alternatives also.


Freeze dried fruit have induced moisture migration.absorbing moisture from the base marshmallow making it crumbly textured.
Cocoa had the same drying effect so there must be moisture adjustments in the amount of water you used in your base marshmallows having these moisture absorbing components.


thank you, i’ll read up on these and have a think about what to do


1 Like