Can I use UHT (ultra-high temperature aka ultra-pasteurized) milk to make buttermilk?
A. We do not recommend using UHT milk with any of our starter cultures (including yogurt, buttermilk, kefir and cheese starters). The process by which UHT milk is pasteurized leaves the milk essentially dead for purposes of culturing and therefore you are likely to have less than satisfactory results when using it to make cultured foods. Q. When does the buttermilk starter expire? A. If kept in a cool dry place, the sealed packet of dried buttermilk culture should be viable for at least 6 months from the date of purchased. Once opened, the dried buttermilk starter, sealed in a plastic zipper-style bag and kept in a cool dry place (such as the refrigerator), should be viable for at least several months. Once the starter has been cultured into buttermilk, it must be recultued every 7 days to maintain long term viability. Theoretically these cultures will last indefinitely if cared for properly but due to inevitable human error, we include the extra dried starter in each packet to be used
