If you're shopping at Costco and want a treat, you can choose from Kirkland Signature frozen yogurt--Costco's store brand--or the soft-serve YoCream--yogurt served from their food courts. While both versions may satisfy your sweet-tooth craving, the Kirkland frozen yogurt has fewer calories and less cholesterol, sodium and protein than the YoCream food court variety.
Both Kirkland Frozen Yogurt and Costco's food court frozen yogurt contain cultured and pasteurized skim milk. This provides the base of their frozen yogurt. Cultured milk products are also known as fermented milk products, indicating they have been incubated with bacteria. In this case, it is the bacteria that makes the milk into an actual yogurt product. Different bacteria impart different tastes and all increase the shelf-life of the product.
Both Kirkland and YoCream yogurts are heavily sweetened. Both contain sugar and corn sweeteners. YoCream's ingredient list includes "sugar and corn syrup," while Kirkland "sucrose and corn sweeteners." Because sucrose is a sugar, but not all sugars are sucrose, it is difficult to determine with certainty that the sugars are the same in both products. The total amounts of sugar added in each product are different, however, since a 4-ounce serving of Kirkland provides 18 g of sugar, while a 4-ounce serving of YoCream provides 16 g of sugar.
Kirkland's frozen nonfat chocolate yogurt contains cocoa. YoCream's vanilla soft-serve version does not. Cocoa derives from the Theobroma cacao tree, also known as the cacao tree and cocoa tree. Cocoa powder comes from the seeds of this plant.
Both yogurt varieties contain stabilizers. These include modified milk proteins and/or whey, cellulose gum, guar gum, and mono- and diglycerides. These chemicals act as emulsifiers, helping to mix ingredients that would not normally blend together. Guar gum, derived from a legume plant, is a long chain of galactose and mannose sugar molecules, while cellulose is a long chain of glucose sugar molecules. In addition to emulsifying, guar gum prevents ice crystals from forming in ice creams and frozen yogurt, and also substitutes for the "feel" of fat in nonfat products.
Kirkland frozen yogurt contains natural and artificial vanilla flavors. YoCream does not list natural or artificial flavors on their ingredient list, but they do list two ingredients not found in Kirkland's frozen yogurt--pectin and modified food starch, both of which increase the gelling ability of the final product. These differences most likely occur due to the fact that one is frozen scooped yogurt, while the other is a soft-serve frozen yogurt. Freezing products tends to diminish their flavors, so more flavors would be needed for the frozen product. Likewise, different consistencies are required for scoopable frozen yogurt compared to yogurt dispensed from a soft-serve machine.
The bacteria listed for the live cultures present in each of these yogurts is slightly different. Both contain S. thermophillus and L. bulgaricus. Kirkland frozen yogurt, however, also lists L. acidophillis, while YoCream lists Lactobacillus acidophilus NCFM, L. acidophilus, and L. lactis. Different varieties of lactobacillus give different flavors and that may account for these "cultural" differences.