Cooking For Engineers

[Nettacow]

Actually, I have the basic tomato sauce down. It's the fine-tuning that I need an engineerish person for.

So, here's how I make tomato sauce: We usually overplant tomatoes in our garden, and the extras that we can't use get rinsed, cored, any bad spots cut out, packed in a ziplock, and frozen. Once the temps and humidity outside go down (i.e. fall), I take the frozen tomatoes, run them under hot water to slip the skins off, and toss them in the crockpot with no lid. It goes on high until they melt down, then low to evaporate the water. (maybe 1-2 days?) I then use an immersion blender to give it a smooth texture, and I have been re-freezing it in one-cup portions, although as an aside I'd like to try canning it one of these years.

Here's my dilemma: I have no control over how concentrated the sauce ends up and therefore how acidic it is, if you will, especially considering variables such as some tomatoes are more ripe than others, etc. I tried subbing some of my sauce in a Spanish rice recipe that called for water and tomato paste (I googled a substitution for tomato paste/water and tomato sauce). From the taste of the final product, you'd have thought I just used watery tomato paste - way too strong. Anybody know a method to test the acidity/concentration? Or some other suggestion? Thanks!

[Dilbert]

Netta -

first, concentration ie sauce "thickness" has zero.zip relationship to acidity.

second, you have complete control over how "concentrated" the sauce becomes. as in, stop cooking it.

you made no mention of any ingredients other than tomatoes. so going on the "you are not adding two bottles of vinegar" assumption, the acidity of the sauce is determined by the tomato strain/type/variety. they do vary.

your local pet store can provide you with pH test strips (commonly used in keeping tropical fish) - which means you can quantify the acidity/pH of your sauce. which brings up the next problem: if you could make the pH anything between zero and 14, what would you like?

since tomatoes tend to the acid side, you can reduce the acidity very simply with something like baking soda. baking soda carries a salty taste - so baking soda first, salt/season later.

>>> 1-2 days in a crockpot
this concerns me. that's a long time in the open air at minimal temps.
I'd recommend you blend it up and use a low heat aiming for 4-5 hours to the desired consistency.

[kgb1001001]

First of all, I'm with Dilbert -- I'd think it would be safer to reduce this over a higher temperature for a shorter time period -- so I'd ditch the crockpot and go with a stock pot on the stove.

As for it being too acid -- that's why you taste it! The easiest way to correct that is to add a bit of sugar -- you don't want to eliminate the tartness; that's part of the beauty of the flavor profile of the tomatoes. Instead you want to balance it with some sweetness. Sugar is the simplest solution, but you could instead add honey or any other ingredient you care to that will balance the flavor.

[Nettacow]

Thanks to both of you for replying - you bring up some good points. Couple of things . . .

By definition, wouldn't more concentrated sauce be more acidic - pulling out the water makes the proportions of everything else go up? I'm just kind of thinking out loud here, which will probably get me in trouble. :>) As for what pH/acidity I'm going for - that of commercial tomato sauce, I suppose . . .

You'd think tasting it would be the easy way to go - but I can't say I care for the flavor of straight tomato sauce and it's difficult to quantify taste anyway, know what I mean? I typically add sugar to my tomato sauce recipes (spaghetti sauce, chili, etc.) anyway, so it might make sense to do it at this stage of the game.

I appreciate your concern regarding safety in the crockpot. I assumed that it was staying well over 140, but if I do it that way again, I'll check it periodically with a thermometer to make sure.

And thanks for the pH test strips mention - I'll take a look and see if it's worth it to dink around with an experiment. Might be interesting!