If you like yogurt, you have to try this!!!

[OakLeaf]

Here's a question: I make yogurt irregularly, and often I'll go too long between batches to keep my starter in the refrigerator. If I freeze some yogurt, will the cultures survive, or do I have to keep starting over with commercial starter?

[KnottedYet]

I never used a starter, just a spoonful of yogurt from the grocery store.

Does a starter make a difference?

[margo49]

It can last in the frig for a couple of weeks plus. They just go to sleep and don't actually die . What kills them is heat (50 deg C plus)
Like Knotted says you can use actual yoghurt as a starter. You can even do this every time (ie keep back 20% of the batch to add to "tomorrow's")

My wee pet kefir is doing really well and stabilising nicely the past few days.

[OakLeaf]

I've had my saved yogurt spoil more than once. I think soy yogurt tends to spoil quicker than dairy. And by "commercial starter," I meant to include store-bought yogurt. I was just wondering if freezing kills the bacteria.

[Jolt]

Well, I decided to try making yogurt today for the first time--we'll see how it goes! I put the glass jar of inoculated milk in a cooler with hot tap water (about 120 degrees) and then wrapped the cooler in a fluffy towel as well; hopefully that will keep the temp fairly constant. I may check it a little later to see if any hot water needs to be added. Then, because I live with two roommates and it's entirely possible for somebody to be tempted to move the whole setup off the counter, I made a little sign saying "Caution: bacteria at work" and put that on top (I am SUCH a nerd...)!

[pyxichick]

I've read that the bacteria don't survive freezing. Thus frozen yogurt doesn't have the same benefits as regular yogurt. But the lactose is digested already, so it's still better on the gut than ice cream.

[Ana]

I love Alton Brown's Good Eats. He has a show on making yogurt. It might be worth taking a look