As a chef in training, my chefs would often say that you cannot create good food from bad ingredients. in most cases I will agree with that. In this one area, I will slightly disagree. Many supermarkets often have a sale rack in the back of the produce department with items that are slightly blemished, a little past prime or truly on their way out to the compost pile.
Let me divert on this topic slightly and say that the produce department is an area that the grocer makes some money in. If you buy a 50 pound bag of cabbage wholesale, in season, it sells for about $9 - $11. The grocer sells it for 49 cents a pound. He has made $15 on that bag of cabbage, a more than 50% profit. He has to make a good margin on these items to offset the loss he takes on other produce that has a poor shelf life and goes bad more quickly. In comes the discount rack.
Often times, I will come across this rack in my local grocer and find hidden gems at a great price that I can use. Bell peppers are a great find. Put them over an open flame or in the oven and roast them. Any blemish is easily removed once it is roasted, deseeded and deskinned. Grapes are another great find. As long as they are not molded and only a little shriveled, make raisins from them. I often toss a container of older grapes into the dehydrator and make a batch of fresh raisins. They are surprisingly better than anything Sunmaid can put out. Onions, carrots, celery or other vegetables can always make a great veggie stock, at the least. Older apples can be used for what they are used commercially- apple sauce or cider. Berries can be cleaned up and frozen on a sheet pan in the freezer to make smoothies, compote or cobbler. Tomatoes can be used for sauce or added to any cooked dish. Citrus fruit can be juiced and make a great drink (I often can get a bag full of limes at the Spanish market for a buck that we use to make lemon/lime ade). Again the Spanish market (see previous post about ethnic markets) usually has a bag of plantains that have over ripened for less than a buck. Bananas are usually marked down to 19 cents a pound for over ripened ones. These are actually how you want them if you are baking with bananas. Peel them, put them in a zipper bag and freeze them. Use them for banana bread or smoothies anytime.
These are just some ideas that I use for marked down produce. Please exploit the opportunity when they present themselves to you and save some money on day old produce. My only guidelines are these- 1/ If it's moldy, forget it at any price. The mold will ruin the flavor of even a stock. 2/ Even if it's not moldy but has degraded to the point that it has lost ability to hold it own structure, it's too far gone. 3/ Assess how much of the produce is truly bad and how much can be salvaged and used. 4/ Cut away any part that is moldy or slimy and add to the compost pile. Use only what is usable. Don't be TOO cheap.
I have talked to the produce manager at own local Walmart and he has told me how they probably throw away thousands of dollars of produce in a week. They are one place that does not mark down produce (at least in my area). Bakery and meat they do, but produce they don't. Explore your options and take advantage of them.