Dehydration

Hello community,

I’ve tried to dehydrate some cherry tomatoes last night by leaving the oven at 80°c average for about 7 hours. I noticed there was always a mist on the door so every once ina. while I was opening the door to let the steam out. However at the bottom of the oven there was quite a bit of water depositing… is it normal?

Steam was obv set to 0, no sous vide and rear heat activated.

The result is that the tomatoes are cooked but not really dry… what happened? I thought the oven would have “push” out the humidity during the process if steam is not activated… and where was it getting all that humidity from?!?

Your typical tomato(es) are 89% or more water, so if you look at the punnet weight, what you used & do the math then spill a similar amount on the worktop you’d likely have some context as to a first time user of this mode (NB I have not, but my own oven airfryer(s) do have dehydrate on them

Is your setting automatic? (just checked my non anova unit) my dehydrate setting is 57 degrees c, considerably lower, (that is for my instantpot which has a seal & not open like yours to give insight as to differences. which may reflect a heat build up, I have not tried, but presumably my settings are adjustable not just factory pre-sets.

The oven variant (with a door that can be opened …akin to yours, the setting is 70 degrees c

Across our 3 units that is quite a temperature difference i’m sure you’ll agree.

Sugar content tends to prolong the drying action, presumably due to “chains” (thus sucrose / glucose heavy items will need longer generally.

Your own localised humidity will be a factor here also, so if it is a high humidity day maybe avoid, or get onto ali express & invest in a few temp / humidity wall hanging units to guage anomalies where you live or because you’ve just released a tonne of moisture vapour from an open pot into the kitchen (for instance)
To throw the cat amongst the pigeons again, (& demonstrate that no two units are the same, thus “guidlines” not definitive timings, I looked on a dehydrator site which recommends no higher than 115f / 46.11 degrees celcius for 10-18 hours. no mention of variety just “dip hot then cold water & slice up to 3/4 inch thick slices”

Basically though pooling water is going to keep the immediate area of moisture up in general, so perhaps it is not so much an overnight thing as a visit every 90 mins & wipe out moisture residue? which would reduce the local (oven) moisture percentile accordingly.

I know you used cherry tomatoes, but did you allow the skins to become porus by a water dip as per above? (a skin softening action to presumably speed up the process)?

Also, humidity locally? what was it?
Marcello, I have linked a comparison site for tomatoes for you to peruse, please note the 3 methods, available & data, they use a dedicated dehydrator, an oven & the sun, they also use super ripe (presumably somewhat softer to the pinch tomatoes, rather than firm under ripe, were yours too fresh maybe as a contributing factor) ?

That link:

You have piqued my interest & reminded me, plant seeds for cucumbers & tomatoes, so thanks for your timely post!