For years and it still hold true if you want to save money especially on the pantry staples, buy in bulk. In general this means buying dried beans, pastas, grains, flours, dried herbs and spices, coffee beans, sugars, loose tea, baking needs, nuts and similar types of foods. The best prices of course will be found if you go directly to the source. For example, buying flours from the flour mill will be cheaper than in the stores. It may not always be possible to go directly to the source. It may be possible to order in bulk through co-ops. There are specialty stores that sell a variety of foods in bulk and now it is possible to order online.
This style of shopping can save money in two ways. First, many foods available in the Bulk Barn and similar specialty stores are a lower price per unit because packaging has been greatly reduced. Second, this style of shopping allows you to buy just the amount of an item that you need. Let's say you want to make a dish that calls for 1 tsp of paprika yet you don't use paprika for any other cooking. If you buy paprika in the grocery store you will pay at least $3 for a small glass container only to use 1 tsp. However, at the bulk food store you can scoop out 1 tsp of paprika if desired which would cost you less than 5¢.
While shopping in the specialty bulk food stores can save you a significant amount of money they can also cost you more than what you would normally pay. The first problem is there really is no way to tell how much you are buying. Scooping the item really is all guestimation so there is the tendency to spend a bit more than anticipated. The second problem is the temptation to buy certain items you normally would not (eg. bulk candies). The third problem is some foods are not cheaper in the bulk food stores. In particular I noticed dried bean prices during my last trip to the Bulk Barn. A 500 g (1.02 lb) bag of roman beans cost $1.89 at No Frills and at the Bulk Barn they were $1.79 so 10¢ per lb cheaper but black eyed at No Frills were $2.19 for a 900 g (1.98 lb bag) or $1.10 per lb while they were $1.79 per lb at the Bulk Barn or 69¢ per lb more. This really becomes a case of knowing unit prices in the grocery stores to be sure you are actually getting the item cheaper at the bulk food store. The easiest way to do this is use a price book so you can easily check to be sure you are buying at the cheapest source.