Q: I was checking out your piece on making homemade yogurt, but the only yogurt I can get here to use as a starter either has sugar or is artifically sweetened. Does that still work for making yogurt?
Sent by Teresa
Editor: I think that as long as there are active bacterias listed in the ingredients, any yogurt will work as a starter for making your own yogurt. You can then use a scoop of your homemade yogurt as the starter for the next batch, and eventually there won't be much of the original yogurt with its sweeteners and artificial ingredients left in your yogurt.
If you'd like to avoid the sweeteners and artificial ingredients altogether, you can also order yogurt cultures online from places like Cultures for Health:
• Heirloom Yogurt Starters from Cultures for Health
Readers, what do you think?
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no, the sugar and flavour start to taste weird when interacting with the cultures.
You're best to use natural yogurt (I find low fat makes a better starter) and flavour it afterwards.
I hate to be picky, but the plural of bacterium is bacteria.
No you can't use sweetened yogurt or yogurt with fillers or artificial ingredients. Part of the process of making yogurt includes letting it "grow" at about 120F for anywhere from 4-12 hours (depending on how thick you want your yogurt). Sugars, fruits, and sweeteners will ferment and spoil the yogurt - and you might even get sick off of the results.
You can order yogurt cultures online. The New England Cheese Company has a couple options that are fairly reasonable, http://www.cheesemaking.com/.
I agree with the others that you can't you a flavored yogurt. A nutritionist once told me that the sugars in commercial yogurt actually kill the live cultures. You can put sugar in your yogurt but you shouldn't buy it that way or use it as a starter. I got my starter from Whole Foods and it's called 'Yogourmet'. It's usually kept in the baking aisle.
I'd look harder
I've done it a few times and it was fine. My recipe for yogurt is 4 tablespoons of starter to 4 cups of milk (I increase the starter by a tablespoon or so if I'm using a flavored starter), so you can't taste the starter in the finished yogurt.
You only need a little bit; even if you have to hunt to find plain yogurt somewhere, the first batch you make will feed subsequent batches.
From a biochemist perspective, as long as there are active cultures, any flavored yogurt starter should work, as recommended by the editor. However, you may need to tweak the recipe a little bit to account for added sugar and there may be a faint residual flavor. There is also a small chance that some of the additives may interfere with the process, but commenter STH and a quick google search indicate many people have had success with flavored starters.
Bacteria tend to like sugar so added sugar should not kill any cultures. Also yogurt is a fermentation process, so fermentation is a good thing and would not make one sick. Of course, spoiled yogurt can make one sick, but yogurt is relatively stable in clean environments, even at room temperature, as it is a method to preserve dairy.