The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

Why ice for steam?

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breadman52's picture
breadman52

Why ice for steam?

Why do so many home recipes call for the use of ice to produce steam? 

My thoughts are: Ice uses more heat energy to produce an equal amount of steam from the same weight of water.

The ice may last a bit longer.

Thanks in advance for your replies.

Doc.Dough's picture
Doc.Dough

I suspect that the rationale for using ice is to delay the steam until the oven door is closed, without any thought about the net energy cost.  It takes 334 watt-sec/gm to melt the ice + 418 watt-sec/g to heat ice water to boiling + 2257 watt-sec/gm to boil the water + ~200 watt-sec/g to heat the steam to 200°C oven temp.  So the net difference in energy use is about 30% more to create steam from ice than from hot water.  So a 4KW electric oven at 100% efficiency (close) will take ~100 sec to recover from throwing in 4 oz of ice (even with a tight, humidity controlled, 15KW commercial combi oven, where the steam generator is internal to the oven, it takes about a minute to recover after loading three or four 1/2 sheets if steam is being used).  The energy difference between using water and ice is 15% max, and it would be easy to convince me that I lost 15% of the steam before I could close the oven door after I poured water into a pan under a baking stone without burning myself.  So ice might be the right answer, and if you preheat something like a cast iron pan on the stove before you put it into the oven, there might be some net savings.  But I am not going to model that tonight.

gerhard's picture
gerhard

I suspect as the ice melts you get a very thin layer of water that will vaporize pretty much instantly and as it will take some time for the ice to melt you will get steam for a sustained period.  No scientist here just my thoughts.

 

Gerhard

Chuck's picture
Chuck

Why do so many home recipes call for the use of ice to produce steam?

Because it works fairly well in old commercial ovens that don't have a steam generator, so the technique is quite familiar to many recipe writers. 

IMHO, ice cubes do not work very well in home ovens, and if recipe writers realized how poorly ice cubes function and how many better methods of generating steam in a home oven there are, they'd stop recommending it in their recipes.

Ice cubes absorb such an enormous amount of energy in melting that they noticeably drop the temperature in a home oven and the temperature may never recover. Often some sort of covered vessel (dutch oven, Le Creuset, half an old roasting pan, a foil roasting pan from the market, etc. etc.) work just as well as more involved kludges (they "steam just the bread", they don't "steam the whole oven").

scottsourdough's picture
scottsourdough

When I don't use a covered vessel, I steam the oven using boiling water. You might need to do it a couple of times, but there's minimal heat loss.

Chapuchan's picture
Chapuchan

That's great.

breadman52's picture
breadman52

When I taught bread classes at the cullinary in Pittsburgh I would often reply "That's great" to some of my students. It's not possible that you were in one of my classes?

flournwater's picture
flournwater

Water produces steam, depending on atmospheric pressure, at roughly 212 degrees.  Put another way, the boiling point (vaporization stage) of water occurs when the vapor pressure is equal to the atmospheric pressure.  Although it is commonly said the that a bread baker may introduce "steam" to achieve certain characteristics in his/her bread, a more accurate statement might be to say that raising the level of humidity in the oven is what the baker is actually working toward.

Inasmuch as frozen water (ice) cannot vaporize until it reaches 212 degrees at sea level, using ice instead of a pan of water in an oven offers no advantage.  In simple terms, the ice cannot produce steam and elevate the level of humidity until it melts.  It takes more energy to bring the ice to melting temperature, and then add enough heat to produce steam, than it would to maintain an equal amount (by weight) of plain water at or near the stage of evaporation for the same purpose.

I use a shallow level of hot water in a pan on a rack below my baking bread.  When I load the oven with the newly prepared loaf, I "spritz" the oven with a mist of water before closing the oven door.  The pan of hot (boiling) water below the baking loaf does the rest of the work.

lazybaker's picture
lazybaker

Because it's easier. That's what I think.

We used to have an old gas oven. I watched that segment from Julia Child about baguettes. Danielle Foriester used about a 1/4 cup of water and splashed it into the oven. I did that, and it was a big mistake. The water extinguished the fire underneath the oven. Luckily I detected gas and immediately turn off the oven.  Whew. But yeah, I wouldn't recommend splashing water into the oven. LOL Now that we have a new oven with a glass window, there's no way I'm creating steam. I don't want to risk damaging the oven.

OldWoodenSpoon's picture
OldWoodenSpoon

I suspect that a lot of those calls for ice instead of water are considering their audience in the most general sense, and directing them to a least-risk, or at least a lower risk, option for steaming.  Ice is easy to hang on to, falls in chunks, and generally it all goes where you put it without dribbling down the side of the pouring vessel.  Result:  less cracked and crazed oven door glass from spilled water.

Another free opinion.  Always worth what you pay for it.
OldWoodenSpoon

GrapevineTexas's picture
GrapevineTexas

because steam was so important on my first.....

'tis a true story.  

BTW, I still create a bit of steam, sometimes with water added to a pan beneath my bread stone (oh, and that's another tale...I've lost count of the number of stones broken by my 'tricks of the trade.'  Then sometimes I use an inverted pan over a loaf.  Spritzing the walls of my oven is another fav.  

In my latest pursuits, I'm working with higher hydration loaves.  There's something to be said for going this route, but the trick is learning how to manage the dough.  ... 

Janetcook's picture
Janetcook

I have tried just about everything and ice cubes remain my favorite mode of steam....

The hot water into a hot pan ended up with steam burns on my face.....

Pouring hot water into a cast iron pan beneath a stone was always risky due to glass in oven door and the oven door had to be opened way longer than when I use ice cubes ....

I have also broken a baking stone with water....

So ice cubes placed in the oven on a long ladle works for me when I am too lazy or the loaf is too big for my DOs.

Janet

Sadassa_Ulna's picture
Sadassa_Ulna

I am three months into a new obsession with sourdough. I still have not taken the plunge to buy proper equipment but I have been quite successful using tools I happen to have. I have experimented with various ways of getting lots of steam generated.  I have many burn marks on my forearms and backs of hands  trying to get boiling water into cast iron pans.

I recently discovered that just tossing some ice cubes into the oven and letting them land where they may works well; some land on the bottom racks and slowly drip water onto the oven floor as they melt. Some land on the actual oven floor and form quickly evaporating steaming puddles. And some land in the cast iron pans I place on the bottom rack. 

Do I risk any damage to my electric oven by doing this?

Thanks!

 

 

 

 

 

flournwater's picture
flournwater

IMO, at some point in time somebody got the idea that ice cubes lasted longer and were easier to handle than a mere pan of boiling water (no hot water splashing around) and promoted the idea until it became popular.  Ice is simply frozen water and the steam from frozen water is no better (or worse) than the steam from liquid water.  The steam from ice cubes is exactly the same as the steam rising form a pan of boiling water resting on the bottom of the oven or one of its racks as you might prefer.  In fact ice cubes do not emit steam.  They first have to melt, then the melted water has to heat to 212 degrees before any steam is produced.  Conversely, with hot water, the amount of steam produced is a factor of the temperature and surface area of the water.  A pan of boiling water with a 9x13 surface area will produce more steam over a given amount of time than a mountain of ice cubes on the floor of the oven.  There is no scientific basis for using ice cubes in place of hot water.

Davo's picture
Davo

Sublimation? Some water molecules at least will go direct from ice to vapour.... In fact, ice can vaporise below freezing temp. I keep some large ice blocks in my freezer, and trust me, they evaporate! And I think freeze drying works by freezing the subject matter, and then lowering the pressure - favouring the vapour phase for the water content.

I don't use ice, but I suspect it is just convenient for some - you can throw it on the floor of many ovens where you can't just splash water in without a pan to hold it. For what it's worth, I use a pan with water in it.