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How to Restore Soft Biscuits


Making stale/soft biscuits dry and fresh again

The Recovery of biscuits, cookies, crisps, and other snacks to make them fresh again! (Even soft chocolate biscuits can be made crisp and fresh again by this method).


Biscuits go soft when exposed to the air, but this is reversible by knowing the right technique. Through experiment I have discovered how to restore soft biscuits, and crisps (potato chips). With a bit of practice the method even works for chocolate biscuits that have gone soft.

Of course there's no harm in eating soft damp biscuits, if that's how you like them. However, the usual preference is for dry, crisp biscuits whose moisture content is low and whose structure is crispy and breakable rather than soggy and bendable.

So, this page details a method for turning soft biscuits into apparently "fresh" or "new" biscuits.

Well, you might say, it's obvious, you just cook them in the microwave oven! Yes, that sounds good, but if you try this it tends to make the soft biscuits into very soft warm biscuits, and further heating produces what might be described as baked biscuits, rather than restored fresh biscuits! What's needed is something more subtle and clever, something that takes away the moisture content without there ever being much heat. (Remember, my technique works even for chocolate biscuits, so it's clearly not just "heating in a microwave oven"!).

Scientifically, boiling water away requires much more heat than just boiling the water. There's something which is the Latent Heat of Vaporisation.

How about a vacuum pump? This works, but it requires a lot of evacuation to dry out even a small number of biscuits, and it takes a surprisingly long time. That's because exposing the damp biscuits to the vacuum of outer space causes them to become cold, and the replacement heat has to come from the surroundings, which takes a while, and that is a problem exacerbated by being in vacuo. Also, most kitchens of the zero zeros decade were not equipped with laboratory vacuum pumps, as these were not required for most culinary procedures of that age.

So, how do you restore soft biscuits then?:

First, get several cold ceramic dinner plates. If the climate's not cold enough, these can be chilled in the fridge.

Now, put a few of the soft biscuits on a plate and put it in the microwave oven. Give it a blast for just long enough to warm up the biscuits but not cook them.

Then, take the plate out of the oven and transfer the warmed biscuits onto a cold ceramic plate.

What happens is the moisture in the biscuits evaporates without boiling and then condenses on the cold surface of the plate.

Wait a short while and then transfer the biscuits again, dry the plate, and repeat the technique a few times. After several cycles of the process, the biscuits will be dry, but not hot!

The same technique works for sliced potato snacks, crisps, potato chips, etc.

The method requires some care to calibrate the amount of microwave time required to warm the biscuits/crisps etc rather than overheat them, but once this has been established, the process is repeatable. It is condensation that's important here, and that's why cold plates are required.

For chocolate biscuits, the same technique is used, but extra care is required to limit the heating such that it doesn't melt the chocolate. As a consequence, more cycles of the process are required. However, the drying out of chocolate biscuits is sufficiently unbelievable to most people that it's almost like a conjuring trick!

Other notes:

* You can't microwave and condense a whole packet of biscuits in one go! For the biscuit moisture condensation to work, all of the biscuits in the batch need to be in contact with the cold plate for some of the time. So, it's limited to however many will fit flat on the plate. Patience is required.

* Biscuit drying throughput rate can be increased by multi-tasking, using several plates of biscuits at the same time, some warming and some condensing. More plates are required, as they take time to cool down.

* Although the technique can be used to dry food that's become moist, and restore soft biscuits, it can't be used to recover food that's gone bad. That requires different techniques, which might yet appear as other pages here!


Other interesting things: Domestic appliances , food , how a microwave oven works , best before dates , selective baddening of bananas , crisps and snacks , don't waste food , how to freeze milk and separate skimmed and whole milk , How to remove sugar from a cup of tea , and how to convert a washing machine door into a mashed potato bowl

This page also seems to have a connection with other restorations, including Restore Mustangs and Restore Classics. Also see Restore Photos Online. Also see Recovery of Lost Data

If you like this site, explore it! If you like this page, link to it, don't copy it. See fair use policy.

You are reading this curious, intriguing, interesting page at Zyra's website, (the .org.uk) which is a website about all kinds of crazy things. Well worth making a note of the address or even bookmarking it.

I believe that this sort of thing adds to the knowledge of the world, so it's worth publishing. If search engines are too poorly made to find it, that's their problem, not mine. I suggest we the people link to pages like this because it is this types of stuff that makes the Real Internet what it's supposed to be!


Shame upon Google! They seem to have demoted this page for "How to Restore Soft Biscuits" even though it is actually ABOUT restoring soft/stale biscuits. If you search for that, then that's what you should get! Yet, I've seen the page of "semi-skimmed milk" come up higher for no other reason than it mentions this page. Time to replace google with a new search engine! Something that lists things that are relevant!