Jeff Yeager, author of "The Cheapskate Next Door," says consumers waste money when buying prepared foods such as shredded cheese and prewashed, prepped vegetables.
"A study by Arizona State University showed that, when computed on an hourly basis, you're paying astronomical amounts for the convenience of processed foodstuff like shredded cheese ($80 per hour) and prechopped celery ($49 per hour) -- simple tasks you could do yourself," Yeager says.
In fact, Ingram compared cheese prices for her blog and found that she could buy 8 ounces of shredded mozzarella for $7 or a 16-ounce block of mozzarella for $4.
How much you can save depends on how much you spend now on prepared foods.