I use your batch weights to connect a cooked portion with a raw food label. This gives you a weight conversion for that batch, not a standard cooking yield or a measurement of the nutrients left after cooking.
Weigh the same batch twice
I would weigh the food before cooking and the same batch after cooking, before taking out any portions. Leave the container out of both weights and use grams throughout. The conversion assumes your portion has the same yield as the whole batch. It cannot separate ingredients with different yields in a mixed dish.
A worked example
Suppose a batch of chicken weighs 500 g raw and 350 g cooked, and you serve 150 g cooked. These are the prefilled inputs, not a claim about how much chicken usually loses. I divide 350 by 500 to get a yieldfactor of 0.7, displayed as 70.0%. Then 150 divided by 0.7 gives a raw equivalent of 214.3 g. The batch weight loss is 500 minus 350, or 150.0 g.
What the weight cannot tell me
A batch that gains weight has a yield above 100 percent and a negative weight loss. Water absorbed during cooking can do this with rice or pasta. The weights alone do not identify what was gained or lost. I cannot use this ratio to measure nutrient changes or account for added oil, sauces or discarded cooking juices. Account for additions separately when using a raw label.
Recheck for the recipe you are making
I would measure a fresh yield for each new batch, especially when the recipe or cooking method changes. A saved result describes the batch you weighed. It does not expire after a set number of days, so there is no timed reminder. Use those fresh weights when you cook again.