A product has an unusual smell, it probably isn’t fit for consumption.
Summary. Even though buttermilk is a product spoiled on purpose, it still can “go bad”. Buttermilk should always be kept in the fridge, where it can last for at least a month unopened or for about two weeks opened. If you want to extend its shelf life, you can freeze it. It’s perfectly normal that buttermilk separates, so you should shake the container or stir the contents with a spoon. If the consistency isn’t similar to the natural one (e.g. the buttermilk is very thick), it’s the best to throw it out. Another way to tell if buttermilk has expired is to check its smell. The buttermilk might have a very sour odor, or it can simply smell spoiled. If your product has an unusual smell, it probably isn’t fit for consumption. Tasting the product is your last resort in the case of determining whether it has gone bad, or no Generally milk will still be good for a week to 10 days after the expiration date, so your butter milk is probably O.K. I know what you mean though about the taste of Butter Milk, However if it is sour, (spoiled,) you should be able to tell by the taste and the smell. I would suggest that if you're in doubt, just go buy another quart. It's better to be safe than sorry when it comes to ingredients. Just my 2 cent's worth. My brother and I used to drink so much buttermilk when we were little!! Nice and cold..so refreshing! The way you can tell if it's bad or not is simple. When it's bad, it will be clumpy, with water floating on top. It won't just be pleasantly sour. 1 You can interchange yogurt, sour cream and buttermilk in most recipes. 2  If you need your recipe to be looser, you can use 1/4 cup milk plus 3/4 cup yogurt or sour cream in place of buttermilk. 3  Let 2-3 tsp. of lemon juice or vinegar set in a cup of milk for 10 minutes to make sour milk. 1 If you want, you can still use it. 2  You just need to replace each 2 tsp. of baking powder with 1/2 tsp. of baking soda. 3  You can interchange yogurt, sour cream and buttermilk in most recipes. 4 Tips & Warnings. 1  If you are at all unsure about the length of time the buttermilk has been open, throw it away to avoid stomach and other bodily complaints. 2  Ingesting bad buttermilk can lead to nausea, vomiting, diarrhea, and upset stomach. 1 I know what you mean though about the taste of Butter Milk, However if it is sour, (spoiled,) you should be able to tell by the taste and the smell. I would suggest that if you're in doubt, just go buy another quart. It's better to be safe than sorry when it comes to ingredients. Just my 2 cent's worth. Ed P.S.  Save. Buttermilk is a milk product that has been intentionally fermented. Milk is introduced to a starter bacteria that makes the milk ferment, but is still useable for drinking and using in recipes. Buttermilk has an unusually long shelf life as long as it is kept cold. 1 If you are at all unsure about the length of time the buttermilk has been open, throw it away to avoid stomach and other bodily complaints. 2  Ingesting bad buttermilk can lead to nausea, vomiting, diarrhea, and upset stomach. You can also use 3/4 cups of yogurt and 1/4 cup of milk to replace buttermilk. In some of my recipes I can tell a little bit of difference in the texture if I use buttermilk over just the “soured” milk made with vinegar or lemon juice that is why I usually use buttermilk when it calls for it. 1 If you want, you can still use it. 2  You just need to replace each 2 tsp. of baking powder with 1/2 tsp. of baking soda. 3  You can interchange yogurt, sour cream and buttermilk in most recipes. 4  If you need your recipe to be looser, you can use 1/4 cup milk plus 3/4 cup yogurt or sour cream in place of If there is mold, then the best option is to throw it out. If there is no mold, but a thick cream, then skim the cream off the top and use it to make butter or whipped cream. If you are using a container where skimming the cream off the surface is not plausible, then shake well and continue using it. Pamela Follett/Demand Media. Determine how long the buttermilk has been open. 1 If you are at all unsure about the length of time the buttermilk has been open, throw it away to avoid stomach and other bodily complaints. 2  Ingesting bad buttermilk can lead to nausea, vomiting, diarrhea, and upset stomach. Sour milk is made by adding vinegar and lemon juice to regular milk to make it sour. Spoiled milk is milk that has just been left out and has gone bad, like the milk in a child’s sippy cup. To make homemade buttermilk, the recipe says to add 1-2 cups of buttermilk you already have to regular milk and let it sit out. 1 If you want, you can still use it. 2  You just need to replace each 2 tsp. of baking powder with 1/2 tsp. of baking soda. 3  You can interchange yogurt, sour cream and buttermilk in most recipes. 4  If you need your recipe to be looser, you can use 1/4 cup milk plus 3/4 cup yogurt or sour cream in place of buttermilk.
http://www.doesitgobad.com/does-buttermilk-go-bad/ http://community.cookinglight.com/archive/index.php/t-6066.html http://www.livingonadime.com/use-homemade-buttermilk-sour-milk/ http://www.ehow.com/how_5825990_tell-buttermilk-spoiled.html http://community.cookinglight.com/showthread.php?6066-How-to-tell-if-buttermilk-s-gone-bad http://www.ehow.com/how_5825990_tell-buttermilk-spoiled.html http://www.livingonadime.com/use-homemade-buttermilk-sour-milk/ http://www.ehow.com/how_5825990_tell-buttermilk-spoiled.html http://www.livingonadime.com/use-homemade-buttermilk-sour-milk/
how to know if buttermilk is spoiled'