With items that go on sale, on a fairly regular basis, I can make a guess at whether or not my supply will last until the next time. But with items which go on sale less frequently, I find I have to be more exacting in my estimations of how long my supply will last. The following has been an effective method for me.
I was rummaging through the freezer a week ago and discovered that I was down to 12 pounds of butter. The next big sale period for butter will be Easter week, most likely. It could go on sale before then, but it could also not.
Butter is an expensive ingredient. Buying a lot of it at the regular price can pinch that budget more than I like. But, if I can estimate how long my supply will last, given our current rate of consumption, I can make changes to our use, now, while those changes could have the biggest impact. This would extend my supply for extra several weeks, and so I could wait for the next big butter sale.
While standing out in the garage, I made a guess in my head that we were currently going through 1 pound per week, the 5 of us. With one pound per week, our 12 pounds would last for 3 months. I use butter in baking, added to skillets, to enrich soups, and for table use. One pound per week sounds about right. But what if we use more than 1 pound per week? I could be off significantly, and not know any better. So it was best to find out exactly how much we are currently using in a week.
When I brought out the most recent pound of butter, I marked the label with that day's date. It was January 19th. Today is the 27th and we have 1/8 pound left (half a stick). As it turns out, we are currently going through 1 pound every 8 or 9 days. My current supply, if used at this current rate, should last 3.4 months, a little better prognosis than I'd guessed.
Knowing this, I also have an opportunity to make this butter last even longer, by choosing recipes which call for less butter, by using saved fat from cooking meat, by using vegetable oil in place of butter more often, by making soft butter spread by adding vegetable oil and by choosing fat alternatives when baking, such as applesauce, mashed bananas, and pureed pumpkin.
(Bonus -- knowing how long each pound lasts, I also now know how much to buy, the next time I find a great sale.)
I mark packages with the date, as I open them, for other items in the house. When I've wanted to know which brand of shampoo was a better deal (as some can be more watery than others), I've marked the lids of the bottles with the date of open. I've done this with laundry detergent and bathroom tissue, too, to determine best value for our use.
It's just a small thing and requires very little time and effort. But marking the package with the opening date gives me more accurate information for my planning and purchasing.
FYI, the package of butter up at the top is what butter looks like when bought at Cash & Carry. One pound is wrapped in a single large sheet of waxed paper. I make "sticks" of butter for the butter dish by cutting each pound into quarters, lengthwise. My "sticks" are longer and more narrow than prepackaged sticks of butter, but I like that. I think we use less butter when the sticks are long and narrow.
