Originally Posted by HEAT
Are you a Food Scientist by trade? ...
No, I've just got a background in science and research (biochemistry, physiology, nutrition), and a bad habit of asking "why" way
too many time. If I don't know the answer to a question - I know how to go find the answer, if there is one.
Originally Posted by Rob Babcock
... At any rate, the weight of the can isn't included on the label, and the brands I buy all list the drained weight.
True Rob, the weight of the can is not included on the label. The weight on the label only refelects the weight of the contents within the can. The reason I weighed the unopened can was to give me a reference point to make sure there was no evaporation ... if the empty can plus it's contents after draining didn't equal the unopened can .. I would need to try to figure out what happened with the experiment since can+tuna+water should equal the weight of the unopened can.
I don't know where you live in the USA - but if it's sold in the USA the weight on the can is the weight of the total contents in the can - not the dry/drained weight. A 6-oz can of tuna in water contains 6-oz of tuna + water. There IS
however a clue as to the drained weight by looking at the nutritional information - at least for tuna. The serving size and servings per can gives a basic clue. For all three brands of canned tuna - the serving size is 2-oz. For the number of servings per can: Bumble Bee tuna was "variable", Albertson's was "about 2.5", and StarKist claimed 2.5. This would fit with the results of the experiment.
Rob, I hope you understand that I'm not picking on you ... just the idea that a 3-oz "pouch" of tuna contained twice as much tuna as a 6-oz "can".
Originally Posted by norgeskog
We have all forgotten that that same size can used to hold 8 oz.
Actually, the old 8-oz tuna cans were
a "little" bigger - about 1/2-inch in diameter and 1/4-1/2 inch in height. This observation has nothing to do with food history or science ... it has to do with amateur radio. I got the plans to build a low power 2-tube radio transmitter that was based on a tuna can chasis (from back in the late 1950's) and it wouldn't fit on a modern tuna can. I saw one at a ham convention a couple of years ago ... beside a "modern one" that was transistorized (using a 1995 tuna can) - there was a difference in the can sizes.
As prices went up - we got screwed around. Instead of increasing the prices, the producers (knowning we would scream about that) just reduced the amount we were getting - thinking we wouldn't notice. An 8-oz can of tuna became 6-oz .... and a 1-lb can of coffee shrank to 13-oz .. and it's getting smaller to about 11.5 oz.
CAN vs POUCH
This was only an experiment to see if a 3-oz pouch of tuna had twich as much tuna as a 6-oz can when drained. That is all! That question could be resolved by very simple scientific means.
Flavor and texture are another matter, as is the difference between Yellow Fin, Blue Fin and Albacore - dark, light and white meat - flake, chunk, or solid. These are subjective personal preferences - matters of personal taste and preference that can't be analyzed in a simple scientific experiment.