Is pre-heating an oven all that important?

[flobadob]

Whenever I'm reading oven cooking instructions it always says to pre-heat the oven first, but does it really matter if you put stuff in an oven and then turn the oven on?

[craft1948]

Thank you...............you've given me my first tena moment today.......

[sherrardk]

I tend to turn the oven on and then put stuff in but you are just adding to the cooking time (it must take about 10 minutes for the cooker to warm up). I don't do it if I am making cakes or bread though.

[pericat]

you mean bread dough ?

[Sachs]

I presume any recipes have been tried & tested in a 'regulated' temperature to achieve the best results. Therefore to achieve the same results you would need to follow the pre heat instructions.

[sherrardk]

No - I meant what I put (maybe it just doesn't sound right) - probably should have put 'although I don't do it if I am making cakes or bread'.

[flobadob]

What does that mean, craft?

[pericat]

..

http://www.youtube.com/watch?v=S8T2URUM_04

[flobadob]

Oh I see, craft weed herself, understood.

[craft1948]

well Lucy after always having gas ovens for 40 years my fan assisted electric oven also takes about 5 minutes too......

[heathfield]

In answer to the question...Different ovens will take different amounts of time to reach the recommended temperature - so food placed in a cold oven will be subject to different warming up times. This can't be taken into account for any given recipe, and means that the end results may not be what you expect. By pre-heating any oven up to the correct temperature, the cooking results from the given recipe will be the same every time..

[lollyone]

I actually thought it was so the bacteria in food isn't warmed up slowly, giving it chance to multiply much quicker. If it goes in when the oven is really hot, the bacteria is killed faster. Have I just made that up?? My Mum told me and I've never questioned it!

[coccinelle]

You're right lollyone, when cooking meat or fish they should be put into a hot oven for the reason you say. if cooking cakes, biscuits or bread if you put them into a cold oven they would start drying out before baking so the result wouldn't be what was expected.

[flobadob]

Thanks, I think I'll pre-heat for 5 mins from now on, cheers for replies.