Being too runny may be due to the kind of tomatoes used. Many are not as suitable for a salsa or sauce as they contain quite a lot of water. Other types are more dense and are better suited for thicker products. Usually plum or sauce type tomatoes are more useful, compared to a store bought, jumbo, or beefsteak type. These bigger types are great for slicing and for salads. Keep in mind that if weighed, your also factoring in the weight of the water. Some pepper types have a lot of water, but some types contain a lot less than others. The weight vs. volume will surely be different. For correcting a runny salsa, suggest tomato paste, or add some dried vegetables (peppers and onions).

I find it frustrating and think weight should be included in all recipes where preserving safely is the goal. Even how coarse or fine something is chopped can make a sizeable difference in weight.

Sometimes I put on my labels, sometimes I don't, but lately my notes always have the weights.

jt

tanya,

Please don't use 600 g of peppers and onions instead of 2.5 cups! It is not the same thing at all and might not be safe.

There's every reason why 28 ml isn't the same as 28 g, and a fluid ounce not the same as a wight ounce! It's for the same reason that a litre isn't the same as a kilogram. They're totally different systems --- litres, ml, and fl oz are measures of volume, and kilograms, grams, and ounces are measures of weight. So it all depends on WHAT you're measuring.

The connection between the two systems is water. A ml of water weighs a gram, which is not a conicidence --- it's the reason those units were chosen way back when in ancient France.

It's easy to see why people get confused, because a "fluid ounce" seems like it should be the same as an ounce. But it is the same ONLY IF what you are measuring is water, or a fluid of similar density. (That's why it's called a "fluid ounce" --- it's the amount of volume that water, or a similar fluid, takes up if it weighs an ounce.)

But chopped onion, green pepper, cilantro, etc. have very different densities than water does. I am guessing you were assuming that 2.5 cups would be 600 g because a cup is about 250 ml, so 2.5 cups is about 625 ml. So that much WATER would weigh 625 g.

But anything very different will have a very different conversion. solid. Think about it --- 2.5 cups of popcorn would weigh a lot less than 2.5 cups of ball bearings, right?

Using weight measurements properly shouldn't give you a different salsa than using volume measurements. To get a proper conversion, you would have to measure the volume of onions, etc. called for, then weigh them. Then use that weight. Which would give you exactly the same recipe.... But you might prefer to measure that way if you have a scale.

To solve your runniness problem, instead I would advise as Ken did --- try using a meatier tomato. OR you could cook it longer.

So, 625 grams of onions and pepper is not the same as 625 ml; as you found out, 625 g is more like a litre than like 2.5 cups, which is way more low-acid ingredients than the recipe is designed to have and therefore might make it a place where botulism could grow.

Does this make sense?

Zabby

Thanks Zabby it does - I'm going to use your suggestion of measuring it out by volume and then weighing it.
Question : I'm going to chop it up very finely to get the maximum volume(and by default weight)even though I won't be chopping it up as finely for the actual recipe. Would that be OK ito safety ? Might seem like a silly question but I'm paranoid :-)

tanyak,

Canning recipes assume a reasonable definition of "chopped" or "diced" etc. If you put more in for any reason --- whether because you add 2 cups when it says 1 cup or because you minced it into teeny bits when it said "coarsely chop" then you are putting more in and it's not the same recipe.

There's a margin of safety built in, since it's assumed that some people will chop on the small side, but if you mince really finely then you're adding more onion or whatever than the recipe calls for and no, you can't assume it's safe. (So, not a silly question!)

By all means, find out the weights and use them to measure in future if it's easier for you to measure that way. But you really won't --- or shouldn't if you are following the recipe --- get a different consistency. (Measuring by weight doesn't mean you can suddenly put in more onion compared to the amount of tomato.)

If what you want is a less runny salsa, again I wd suggest a meatier tomato or more cooking (you want to end up with less water, not put in more low-acid ingredients).

Another thing you can do is let your chopped tomatoes sit a bit and drain before you put them into the pot.

Good luck! I'll be interested to see what the weight equivalents are.

Zabby

OK, someone please correct me if I am making a mistake here but .... I think you can solve both problems if you use ReadingLady's method of measuring, which is by liquid displacement. Let's say you want 2 cups of chopped tomatoes. If you take a 4 cup measuring glass and fill it to 2 cups with water, then add chopped tomatoes until the water level is at 4 cups, you have added 2 cups of chopped tomatoes. This would be the same whether you chop in big or little pieces. You could then strain it and weigh the tomatoes.

Now, if you added very juicy tomato parts without draining first, you will lose some of the tomato volume when you drain. So instead, you could chop and drain the tomatoes, then measure out the 2 cups, drain, and weigh.

Does this make sense? You would then be able to chop as small as you like, also draining will make it less runny, and you will get a weight measurement you can use in the future.

Zabby? Carol? Am I right, is this an okay way to do it?

Ann, not an expert, so let's see what the others say....

Ann, I'm not sure about that. I always thought 2 cups of onions meant to keep dropping in onions until the top of the flattened pile was at the 2-cup mark. There would be air in between, so if you put those onions in 2 cups of water, the total would be less than 4 cups because the air doesn't get under the water. So Carol's method would work for recipes that assume liquid-displacement measurement, but not for recipes that assume loosely packed ingredients.

Tanya and Zabby, most produce has a lot of water in it (as do our bodies), so 1 mL = 1 g might appear to work for some things, but Zabby's right that it's not a safe conversion. On the show Good Eats, Alton Brown used to say "a pint is a pound the world around" and exchange weight with volume when measuring. This always bothered me. In fact just now I went to the kitchen and weighed an unopened half-gallon of milk. Milk is mostly water, with some cream mixed in which is lighter than water. 4 pints of milk in the container weigh 4.5 pounds (4 lb, 8 oz). I also have an almost-empty milk carton, which weighs about 5 oz. So milk, which I would expect to be lighter than water, is heavier in pounds than in pints. Bad unscientific maxim!

Melissa

Melissa,

Exactly! And even less close with something like green peppers. Tanya found that 625 g was not the 2.5 cups she expected but about a litre, or 4 cups (ish).

Alton can do what he likes when he's cooking, but where exactness matters, like in baking and in canning, I'll follow recipes as written, thanks.

Or convert in a more certain way, like measuring, then weighing, as Tanya will do. Weight IS a more accurate way to measure, after all. In Europe (and presumably South Africa, where Tanya is), cooks all have a scale in their kitchen and weigh most things other than liquids....

Zabby

Hi This is the measurements I came up with after converting the volume measurements to weight measurements :

Tomatoes 8 cups/1892.72ml/1749.71g Ratio : 0.92

Onion 2 ½ cups/591.48ml/330.89g Ratio : 0.56
Green pepper 1 ½ cups/354.89ml/115.67g Ratio : 0.33

Cilantro ¼ cup/59.15ml/23.66g Ratio : 0.4

Interestingly even the weight of 5ml salt,cumin and pepper differs - salt being the heaviest and ground pepper the lightest.

Thanks for the help all !