This has always seemed backwards to me

It's like the old poser, "Which is heavier, a pound of feathers or a pound of lead?"

I always understood the reason for weighing flour to be that the volume can vary greatly due to the amount of air, not water in it. Some flours -- even of the same type -- have been "fluffed" more. Think of the difference between a cup of flour that has been spooned in, one that has been packed and tamped, and one that has been sifted; all of them leveled. The volume may appear to be the same, but the weight -- and the total amount -- is different for each.

So they will each absorb a different amount of liquid. Weighing flour ensured the same flour-to-water ratio every time. (Although as the bread bakers will tell you, even that is not always the case; but at least it's closer.)

I am in the camp of those who say "Get rid of your measuring cups and get yourself a scale; your results will be more consistent."

 

Baking by using weight to measure your ingredients is much more accurate than measuring by volume, that is, measuring cups.

 

Measuring cups are great for measuring liquids. Period. Take a first year college chemistry class and you'll see what I mean.

May I also add that water density changes with temperature and when dealing with numbers as small as 1/10,000 'th, measuring water must be done with a scale graduated in 100'ths of a grain.

In baking for quantities, then, the scale is the most accurate way to go.

 

On the other hand, one of the old timers at a baking supply place we used to buy from, Walter from JAR in Lincoln RI if anybody knows him, told me that a 50 lb bag of flour can vary by as much as 15% due to moisture in the flour. That's quite a bit I think, and will definitely throw a formula off, expecially if you're emptying that whole bag into the 80 qt Hobart. That means every pound you measure out will weigh 18.4 oz. But every pound you scale out will weigh a pound. It's still going to screw up your formula because it's wetter. I almost always find myself making small adjustments when making bread, usually with the water because I always weigh the flour. And that's why I find Roses' new bread bible to be ludicrous, as she measure percentages so minutely. I disremember if Reinhart does or not, but please....

 

I think there might be two issues here which have been combined and therefore clash:
(1) that it is commonly said that the humidity of a flour varies and will affect its weight, and how much water you need to add to a dough;
(2) that measuring by weight is more accurate than by volume, but would appeat to be unreliable, given (1).

I read recently (in Bread Baker's Apprentice, or On Food and Cooking, or??) that the humidity issue is almost insignificant. (It is fluctuations in the hardness of the wheat, and similar variables, that are more important.) This seems to contradict thebighat's 'Walter', but there might be an explanation:

If Walter assumed that humidity was the explanation for variation in the weight of his (nominally) 50lb bags, then he may have been attributing any discrepancy to the wrong reason... This is just a suggestion. By law, the actual weight (or volume, depending on the product) of a package is permitted to vary within a certain range of the nominal weight/volume specified on the package. I don't know what percent this permitted variation is in the USA. And, of course, there may be variation outside the permitted range, due to poor measurement by the manufacturer, leakage, etc.

 

umm, ok, the question is obviously academic.

First question to ask about the recipe: what type of scales are being used. The tolerances of the equipment used are going to affect the end result - due to how precise or inprecise the method used.

Second question (or really, more of an answer) is that to ask your self; what company sells products by volume?. Chances are, packets will state "this product is sold by weight, rather than volume and as a result, some settling may occur". This alone would provide a solid evidence, that what you can feel, as opposed to what you can weight, generally can differ.

As to the old question of what what weights more, a pound of feathers or a pound of lead, easy, they both weight the same. However, the density of both items are going to vary, given that mass is relative to its structure.

The bottom line, is that ingredient items have variations. Whether it is based on its relative gravity, or its protein content, considerations have to be made on its suitability in the workplace.

p.s. Merry stinking hot day (i mean christmas ehh lamington)