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Use Spoiled Milk in place of buttermilk?

I, recently, met a gentleman that keeps his old spoiled milk around for when he needs buttermilk in waffles or baked goods. He says they are perfectly interchangeable. This guy is a chemical engineer so I assume he knows what he is talking about.

Once we get past the initial “eeck” factor, do you folks think spoiled milk is an acceptable substitute for buttermilk in baking?

Another question. Wouldn't it be easier to acidify a cup of milk when I make waffles rather than keep buttermilk around?

I have listed some definitions below; I think we may need for this discussion. Hopefully, I haven’t butchered them too badly.

Soured Milk or Acidified Milk
1 tablespoon of lemon juice or vinegar in a cup of milk and left standing for 5 minutes.

The thin liquid leftover from making butter.

Cultured Buttermilk
Milk which has had a culture of lactic acid bacteria added to simulate the naturally occurring bacteria found in old-fashioned buttermilk.

Spoiled Milk
It is milk that has been too long in the refrigerator and turned sour. It has a distinctive smell and appearance, depending on when the milk turned. It might taste bitter as it begins to turn. It also will smell sour. As it continues to spoil, milk develops chunks that are curdled milk.

Home made live yoghurt
The milk is first heated to kill any undesirable bacteria and make the milk proteins set together rather than form curds. The milk is then cooled. The bacteria culture is added, and the milk is fermented for 4 to 7 hours.

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  1. This reminds me of a story my wife shared with me. It seems her father liked to drink buttermilk. As a girl, she used to give him a hard time about it. She would ask.."So Dad....How do you tell when buttermilk has gone bad?"

    1. All microbiology and chemistry aside, I've tasted spoiled milk. It was unpleasant. It doesn't taste like buttermilk (which I like, even all by itself) and I wouldn't use it as a substitution,

      2 Replies
        1. re: cowboyardee

          kind of the same thing I go through often when making ricotta cheese in my kitchen.
          the consistency is correct but the flavor is off putting, thinking it tastes like spoiled milk cheese

        2. Like you, I rarely have buttermilk around if I decide I want pancakes etc, so I do tend to go off-piste with slightly dubious dairy products. I would substitute milk that was "on the turn", rather than fully sour and lumpy. I also wouldn't substitute the full amount of dodgy milk, i'd use up a mixture of whatever odds and end of sour cream/yoghurt/cream/milk that I had in the fridge.

          However if I was cooking for anyone other than myself, and anything other than a lazy breakfast, I'd probably just go out and buy some buttermilk!

          1. I often add lemon juice to milk for buttermilk. It adds more fat since I usually use whole milk vs low fat buttermilk that you get in stores. One reason for using buttermilk or lemon juice/vinegar/acid is to react to the baking soda in the recipe. I also use powdered buttermilk which also works well. I don't know if soured milk has more acidity than regular milk. The recipes I've seen for it have added acid but you do get the tart/yogurt/sour cream taste w/ the soured milk.

            1. I do know that milk that has gone off naturally (as in, turned while under refrigeration) is a fine and acceptable substitute for buttermilk, especially in small doses. I've used it many times when I didn't have a lemon around to sour milk, and whomped up a howlingly good batch of biscuits with it. On the milk-souring tip, if I do add lemon or vinegar, I stir the few drops in and let it sit for more like a half-hour........I'm sure you've noticed that your milk develops a thick top layer after a few minutes, but after a half-hour the whole cup has taken on the thicker consistency, which I think makes for a more consistent result.......especially in baking.

              1 Reply
              1. re: mamachef

                Thanks, Mamachef, you are one of my favorite hounds!. A friend just gave me an old fashioned recipe for "clabber cake". She says that when milk goes bad, she puts it in the back of the fridge until she wants to make the cake. I made a face at that, since my sour milk has always gone down the drain, and she was surprised! I am definitely going to try it. (My friend and I both live where buttermilk, even the powder, is not available.)

              2. Milk that is sour but not lumpy is my cue to make mashed potatoes or bake something like cornbread. If it gets to the lumpy stage, the dogs get it. I routinely thin plain yogurt with water if I don't have either sour milk or buttermilk for a recipe that calls for the latter.

                4 Replies
                1. re: greygarious

                  Speaking of the lumpy stage, if milk is kept in the refrigerator, I think it would take weeks to get lumpy.

                  1. re: Hank Hanover

                    On occasion, my fridge is a time capsule for items I don't use often, like milk ;o)

                    1. re: Hank Hanover

                      One would think that,wouldn't they? I took some milk out of the fridge that was dated May 21, so it was 6 days beyond date and had been kept in the fridge except just to pull it out and use it for cooking.It was lumpy,chunky stuff. I was making fried cornbread and had dumped some into the dry ingredients before I realized there were lumps. I added some water to the batter and fried it anyway,thinking I would toss it out to the outside critters if nothing else. But my daughter and husband thought the cornbread was good. I had already dumped the rest down the drain.

                      1. re: MellieMag

                        A lot has to do with how many times it was taken out of the fridge prior to the expiration date or how it's temperature has varied . I've had milk that was barely used sit in a fridge for well over a month after the expiration date and it was not sour or lumpy and smelled like milk. I was amazed.

                  2. Milk that has soured is different than ultra-pasteurized milk that has gone bad. The latter has a really disgusting smell. It is my general understanding is that it is harder for today's commercial milk to sour in a way that is useful in cooking.

                    I use milk with lemon juice when I am out of buttermilk, but it is not as sour and in my pancake batter the result is thinner.

                    9 Replies
                    1. re: cocktailhour

                      When one had a choice between homogenized/pasteurized milk and just plain pasteurized, we always got the latter because, as Mom explained, "Homogenized milk doesn't sour, it just ROTS!" She was really annoyed when that was no longer an option.

                      Milk that has only just gone "off" enough to curdle in coffee but not enough to taste terrible might be worth using, but any souring past that gets it dumped around here. I just do the white-vinegar thing if I need some buttermilk for biscuits on short notice.

                      1. re: cocktailhour

                        Mom used to save what she called 'clabbered milk,' for baking biscuits or cornbread. However, in later life, she swore that "today's ultra-pasteurized milk" wouldn't properly clabber, just turns sour. True?

                        1. re: cocktailhour

                          There is a huge difference between "sour milk" which is less fresh unpasturized milk, "old milk" that is pasturized and picked up off flavors but is not spoiled, and "rank" ultrapasturized milk. The first two are fine for baking. The second is rank.

                          I've never heard that homegenization has anything to do with souring. It only related to the fat being evenly dispersed in the milk.

                          Ultra-pasturized milk is horrid when it is fresh too. I won't touch it.

                          1. re: JudiAU

                            I wonder if, in non-homogenized milk, the thick puck of fat at the top of the milk jar has a sort of preservative quality in the same way that the puck of chicken fat seals the air out of a rich chicken stock.

                            Mr Taster

                            1. re: Mr Taster

                              Stock starts out sterile due to boiling. The fat seal forms before bacteria and mold have a chance to colonize the gelatin rich stock.

                              Raw milk sours due to bacteria that is already present. Cream can also sour naturally.

                              When pasteurized, milk is brought up to a target temperature, and then rapidly cooled. If bottled before cooling, the cream that rises to the top might protect the milk below. If cooled and then bottled, then the sanitation of the bottling equipment is critical.

                              But as I wrote cream can also sour. And once you pour off the initial cap, the milk is not longer 'protected'.

                              1. re: paulj

                                Hum. Interesting. It does seem like good quality cream lasts for an awfully long time. I've always assumed it was the higher fat content.

                            2. re: JudiAU

                              most organic milk is ultra pasteurized.

                              1. re: divadmas

                                Trader Joe's organic milk is not ultra pasteurized.

                                Mr Taster

                                1. re: divadmas

                                  It really depends on your area. In my area, no. If you shop mostly at big box stores that traffic in second rate dairy trucked in from other states (Horizon), yes. And the irony is that they often charge a premium for this, the lowest quality of all organic dairy brands.I

                                  f you shop at stores that source their dairy locally than it is not. I would have to go out of way to buy ultra-pasturized organic dairy. Why people choose to buy that nasty milk is beyond me.

                            3. How about using milk that has just turned sour (not yet lumpy) to make cultured buttermilk by adding some just-purchased cultured buttermilk to it (4:1 ratio)? I plan to leave it at room temp for 24 hours like I usually do when making cultured buttermilk from "fresh" milk. Can someone more knowledgeable foresee any issues?

                              I have made yogurt with "old" milk, but I was more comfortable with that since the milk is heated.

                              6 Replies
                              1. re: bmorecupcake

                                Troubles may arise if too many unfriendly bugs have taken hold of the gone off milk before you add your more favorable cultures. They will most likely go unnoticed unscathed, you may see them take hold or smell them eventually, or all might be fine until you eat it and get sick. It all depends on how much the milk had turned already and with what bacteria, so there isn't a real practical way of telling.

                                That being said, if the milk is just sour, to me that is good bacteria producing lactic acid and would probably be find to overwhelm with some more buttermilk cultures to give it all a fighting chance. You wont end up with buttermilk however, due to the milk proteins that are still present. Something more Yogurt-y I would expect, which you would then be able to turn into delicious cultured butter and buttermilk.

                                1. re: Mcooper

                                  Mcooper, thanks for the detailed response. I am still confused why I wouldn't end up with buttermilk "due to the milk proteins that are still present". Specifically, how would these milk proteins be different than when I make cultured buttermilk with unexpired milk? I mix a 4:1 ratio of milk to buttermilk and let sit for 24 hours at room temp. Or has that not been cultured buttermilk this whole time, but rather some yogurt-y thing?

                                  1. re: bmorecupcake

                                    I believe the potential problem is that when you make buttermilk, what you're doing is culturing a specific microbe in the milk. You're adding buttermilk to fresh milk and creating favorable conditions for that bacteria to culture as opposed to other bacteria.

                                    When you start with milk that's already started to sour, you've already got a critical mass of competing microbes in the mix. Those microbes likely have their own 'defenses' that encourage their growth and discourage the growth of competing organisms - namely the one you want to culture. There are more than one bacteria species that can grow in milk and produce lactic acid, and I'm not sure that they all create the kind of buttermilk we know and love.

                                    The end result? I don't know, to be honest. You may get buttermilk. You may get something similar but a bit different. You may get very spoiled milk. Potentially even something that's dangerous to drink or use. Likely, you'll get inconsistent results.

                                    I should add that I'm speaking from my offhand understanding of the process and not actual trial and error in culturing starting with soured milk.

                                    1. re: cowboyardee

                                      Thanks for the detailed explanation! The "buttermilk" looks and smells fine. Will probably bring myself to sample a taste today.

                                      1. re: bmorecupcake

                                        Sorry for the confusion Bmorecupcake. Cowboyardee is correct.

                                        Regarding the confusion as to why you might not get buttermilk due to milk solids - that was a misunderstanding on my part - can't have been paying full attention. I've made cultured butter in the very same way you're making buttermilk, only I used cream that wasn't sour and added buttermilk. I took it a step further to get cultured butter, and buttermilk as an end result - both were quite delicious!

                                        I believe there are about a half dozen lactic acid producing bacteria often found in milk, all of them are fine for consumption and develop their own, slightly different sour flavor. There are more around, but they are rarer in milk. The pathogens found in spoiled milk will lend their own funk, which you will most likely be able to smell, or you will see some as a mold that is producing toxins.

                                        So you aren't 100% safe drinking your buttermilk, some people wouldn't drink it, some would, if it smelt and looked good to me, I would :-)

                                        1. re: bmorecupcake

                                          Well, whatever it is, it's delicious. Used some today in a batch of pancakes. Haven't made pancakes this good in a long time. I hope to try some in a non-red velvet cake (red velvet cake recipe without the red).

                                2. I once cultured some bacteria from regular supermarket milk that had gone off. It turned out to be quite closely related to the bubonic plague and had the potential to make you very ill. So I tend to steer clear. :)

                                  3 Replies
                                  1. re: Mcooper

                                    Milk that has been pasteurized, especially the higher temperature versions of the method, has little of the original bacteria present. It keeps longer without spoiling, but when it does spoil, it is less likely that a benign strain of bacteria is doing it. Hence a wider range of experiences when using 'spoiled' milk.

                                    When baking, what's the point in acidifying the milk, that adding the acid to the milk and letting it sit a bit? Why not just add the milk and acid separately to the batter?

                                    If you used baking powder, you can also use buttermilk without any extra baking soda. In theory, at least, the buttermilk flavor (acidity) should come through stronger. However acidity slows down browning. I think I've detected that pattern - biscuits with buttermilk but no baking soda don't get as dark as ones with plain (powdered) milk.

                                    1. re: paulj

                                      If you let the milk-acid mixture sit for a while, it thickens up so you get a closer consistency to buttermilk than you would if you added the milk and acid separately. But like Mamachef mentioned above, you have to let it sit for quite a while. I've found that if you use half-and-half instead of milk, it thickens up in a few minutes (although then you're throwing off the fat content, which might be just as serious as throwing off the liquid in a tricky recipe).

                                      That's interesting about the browning. I'll have to look for that next time I make something with buttermilk.

                                      1. re: BananaBirkLarsen

                                        The thickening would matter when making a salad dressing. But when baking something like biscuits, I wonder if it matters.

                                        What is the thickening? My guess is that the acid is producing a change in the milk proteins, not enough to make curds. Adding acid to warm milk is one way of making cheese. Citric acid probably works just as well as lactic acid.

                                  2. Cultured buttermilk contains a known starter while spoiled milk contains an unknown bug. Since the bacteria or yeast is unknown, I will toss the spoiled milk.

                                    1. I think it's easier to keep the dried powder on hand that I add to milk to make a buttermilk substiture. It's readily available in most grocery stores in east Tennessee in the dried milk powder part of the stores.

                                      1. For pancakes - I just use regular milk. Seems to work just fine.

                                        3 Replies
                                        1. re: Soop

                                          If the recipe is already using baking powder at roughly the 1 tsp per cup of flour ratio, the use of buttermilk and baking soda is entirely optional - at least from a leavening standpoint. And if needed you can replace the baking soda with baking powder.

                                          Other than that buttermilk adds a bit of its own flavor, and may alter the pH of the dough (depending on the acid to baking soda ratio). I mentioned that a more acid dough does not brown as readily. pH also affects the texture, though that is usually something that only industrial bakers focus on, using one or more of those multi syllable chemicals at the end of the ingredients list. In fact they worry about the final pH as much as the initial.

                                          1. re: Soop

                                            Soop---I don't know your pancake recipe but some recipes depend on the combination of acid and baking soda to raise the batter. If you add a teaspoon of vinegar or lemon juice to your regular milk you may get more lift. (There is even a toy boat that uses jet fuel made of vinegar and baking soda---the combination gets bubbly and creates a whoosh.)

                                            1. re: Querencia

                                              I remember that toy! But yes Paul, my pankakes use Baking powder rather than soda.

                                            1. Bleeeeehhhh......spoiled milk. Wouldn't substitute it because it's not necessarily as sour as cultured buttermilk, it just has an unknown bacteria over-growing. That bacteria MIGHT produce lactic acid, or perhaps Listeria poisoning, you just wouldn't know.

                                              Of course I realize you're going to bake all the bacteria into oblivion, so it's no harm done, but
                                              a) spoiled milk is gonna stink up the fridge b) my elderly dad might drink it by mistake and end up with a s**** little problem that I could have avoided c) the finished cake may not have the flavour I wanted.

                                              Personally, I like to know exactly what I'm cooking with and use the freshest ingredients possible.

                                              1. Aaagh! "Is my fish/meat/milk OK? It smells bad."
                                                When I read these posts I think "If it smells bad, it is beginning to decompose, to rot. It is no longer for the living, or of the living -- bury it!"
                                                Some that I've read here has convinced me that maybe (just maybe), in very specific cases, I might be too rigid in my thinking.

                                                3 Replies
                                                1. re: blue room

                                                  My mother used to keep "old milk" in a container on the counter at room temperature. It was whole milk and it becamed sour and thickened. She would use it in a spice cake recipe which has been lost. It was called "Wilmington Spice Cake" and had a crumb topping.

                                                  1. re: blue room

                                                    Just before this thread was resurrected, I finished eating a late lunch including instant mashed potatoes. I keep the flakes on hand for whenever I have milk or cream that is spoiling and needs using up NOW, since the instant can absorb more dairy than fresh-cooked potatoes will.
                                                    This time it was several ounces of soured evaporated milk. Before it turned, I was planning on making pudding with it but never got a "round tuit", that most elusive homekeeping tool! Flavored with cheese or garlic, mashed spuds made with spoiled milk taste fine and have never caused me any illness, but I concede that my gut flora are the microscopic version of a Navy SEAL team, compared to most folks' conscripted inductee flora. They've been trained over the years by preserves and applesauce that had been festooned with blue=gray mold, irridescent cold cuts, and the like. I subscribe firmly to the idea that a healthy immune system is developed and maintained by frequent exposure to germs, not by avoiding them. Within reason.

                                                    1. re: greygarious

                                                      sour milk can have different bacteria working on it. if i suspect milk is getting old and not already turned i will scald then mix about 1 part buttermilk with 3-4 parts milk and leave in a jar out on the counter at least 24 hours but well less than 48. the active culture makes a thin yogurt like consistency. i use it as buttermilk and it will keep in fridge for at least several weeks. you have to use more storebought buttermilk to make more though. i just did this with fresh milk and no scalding. doing this with cream makes marscapone you can put it in strainer to drain to firm it up.
                                                      we are germophobic though our bodies contain more bacteria cells than human cells, bacteria are just smaller cells. but we do react differently. my niece has gone to the hospital over older bread with no visible growths that other people were eating with no problem. i have often picked off moldy spots and eaten the bread with no problem. i do draw the line at the shiny lunchmeat, though.
                                                      i think the difference between spoiled clumpy milk and just sour milk is pretty clear. though i just made some coffee and added some older organic milk that looked and tasted fine. there were small clumps that would not stir out. it tasted ok but the texture was off in the top half inch so i tossed it.

                                                  2. What were your results for the acidified milk!?