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Making Mozzarella at home... what went wrong?

My first attempt at making cheese just failed miserably. Followed the directions to the “T” on a standard Mozzarella recipe and it just didn’t firm up after adding the rennet. The recipe called for ½ tab, and when that didn’t work after several hours (recipe said it would firm up after 1 hour), I tried to salvage by adding another ½ tab. Still ended up with a sloppy mess rather than something I could cut into cubes before draining. What went wrong?

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  1. What was the recipe and procedure?

    Did you add an acid? Almost always it's citric acid. It's an essential.

    What was the temp of your milk? Should be 90 degrees F.

    Did you cut through the barely-set milk, acid and rennet mixture while it was still in the pan? You usually do this about three times, allowing the mixture to rest between cuts. You have to maintain the 90-degree temp while doing this. At this point, the mixture will look like cottage cheese.

    The "cottage cheese" is then put into cheesecloth and then hung and drained. After four hours, it's solid lump. But it's not mozz.

    Did you stretch the curds? After the solid lump is drained, it's cut into cubes and these are heated in hot water. Then you sort of gently mush all the curds together until it forms what kind of looks like super-elastic pizza dough. Then you stretch that, over and over, just like pulling taffy. Stretching is similar to kneading bread -- it forms the structure. Here's where the acid is important. Acid to mozzarella is like gluten to bread. Can't make bread without kneading, can't make mozz without stretching. Stretched mozz goes back into hot water, then into a container. Allow to cool at room temp, then refrigerate. Done!

    Did you go through all these steps? It sounds complicated, but it's really a snap.
    And then you have fresh made mozz as beautiful and tasty as any in an Italian food store.

    Please post your recipe ingredients, and paraphrase the procedure as best you can (to avoid copyright issues.) We can pick it apart then, if necessary.

    I hope you haven't thrown your "mozz" out. You just haven't finished it yet, and it's fine to make mozz over several days.

    Hope this has helped.

    13 Replies
    1. re: maria lorraine

      Maria, thanks for offering to help.

      No, I did not use citric acid with the recipe I had. Instead I made a "starter" using live yogurt and milk. This process appeared to work very well. The problems started when I added my "starter" to a gallon of milk that was warmed to 90 degrees. I let the mix sit for "1 hour to ripen" then proceeded to add 1/2 tab of rennet. This was supposed to sit for another hour at 90 degrees after which time the curds should have thickened/set. This did not happen, so I left the mix and went to bed expecting to find it "set" this morning. Still nothing but soup. That is when I added another 1/2 tab of Rennet (to try to salvage the whole thing) and even after several hours of leaving this mix, again it did not set up at all.

      The recipe was supposed to continue with my cutting the set mix into cubes and draining/straining through a cheesecloth but the mix I had wouldn't cube or go through a cheesecloth (it just blocked the whole thing up because there was no distinguishable curd from whey). I actually did try to see if I could smoosh the mix together to see if if would "hold together" before I finally gave up and dumped the whole mess.

      What I am thinking is that perhaps my yogurt starter (which presumably produced lactic acid rather than citric acid) just wasn't getting the job done. Perhaps I should try again using citric acid instead.

      I did throw it out, because to my mind I have already been working it for several days and it wasn't something that I felt I would eat at this point even if it did 'come together'. Basically, there were no curds or cottage cheese to stretch, it was just like a slightly thickened cream in consistency. Very odd.

      1. re: SpareRib

        If it's any comfort, nearly everybody fails at mozz the first time.

        I am sure that the acid in the yogurt culture was not powerful enough.

        Citric acid is always the acid of choice for mozz. Buy it at the health foods store or at cheesemaking or winemaking stores. 1-1/4 tsp. per gallon of milk. BTW, that's a lot of acid.

        I used ascorbic acid when I first learned to make mozz, but I'd never choose it now -- it's a little weak. I'd guess that your starter culture was many times weaker than the ascorbic acid even.

        What kind of rennet did you use? Liquid rennet is a lot better than capsules, but I don't think we know how well your rennet works quite yet, because you didn't create an acidic environment where it could "do its stuff." Sure, try again!

        So here's the way I build it:
        1. milk + citric acid -- warm to temp (then add optional Th culture + lipase*) -- let sit one hour
        2. with mixture at temp, add rennet and let sit 15 minutes -- it will have coagulated by this point, and you will be able to cut it. This is like drawing a knife through thick custard, but it will turn into liquid-y curds.

        *Practically everybody I know who makes mozz a lot also adds a thermophilic culture and lipase enzymes to the citric acid and milk. The Th culture helps with acid, and the lipase helps make the mozz taste more like mozz. Lipase enzymes are animal enzymes so vegetarians may not want to use them. You don't have to add them, but it helps make a more mozz-y tasting product.

        You might want to do a little research on mozzarella making online, and read other procedures. I've given you the classic procedure that nearly everyone uses.

        I've found it's unbelievably helpful to see it mozz made in front of you by someone who knows how to do it. It's good to see what the milk looks like when it's first coagulated, and the curd-stretching. Is there an Italian grocery around you or do you know an Italian family or Italian chef or "charcuterie" person who makes his own mozz? Call around and ask if you could observe. You may have to wrap your head in a bandana or wear a hairnet (SOP in cheesemaking), and look/be pro-kitchen clean, but go for it!

        1. re: maria lorraine

          Thanks so much for your input. What you said confirms what I thought was going on. The whole process appeared to stall when the yogurt was supposed to produce enough acid to break the milk down into water and solids. I'm going to take your advice and give it another shot with citric acid this time around. Get that thing jump-started!

          I will certainly look into lipase, and I have a bunch of the thermophilic culture left over in the freezer.

          I'll let you know how it goes. Thanks again.

          1. re: SpareRib

            Don't give up. You should have seen my first batch. I made lots of
            little white rocks. I think Maria will get you going.

          2. re: maria lorraine

            i was reading your instructions and i had a question. me too i tried to make mozzarella last week and failed to do so :-(
            you say to add the citric acid in the milk, warm it and then wait 1 hour before adding the rennet.
            if i do this my milk will have already coagulated by the time i am to add the rennet. what should i do? cut it, mix it with the whisk and then adding the rennet?
            thanks for the help

            1. re: steppan

              Steppan, I responded to you via email offsite. You don't have to wait an hour after adding the citric acid to add the rennet. When you add the rennet is more a function of the temperature of the milk. The method in the following recipe is to add the citric acid as you're heating the milk very slowly. Once the milk temp hits 88 degrees F, you stir in the rennet.


        2. re: maria lorraine

          Hi Maria,

          I have a question..
          I failed mozzarella three times with yoghurt starter. yes, I am stubborn at times :)
          although that was the official recipe in many sources I found, it didnt seem to work out.
          Now I am considering using citric acid but I am wondering if I can simply use lemon juice or vinegar instead of buying separate citric acid?
          If the answer is yes, then what is the proportion, say per 1 liter of milk?

          1. re: tcinlarses

            IIRC, lemon juice or vinegar is not acidic enough. You need a stronger acid to make mozzarella. Did you say you used yogurt starter? Why? What about rennet, thermophilic culture and lipase? These are basics in making good mozz, IMO.

            1. re: maria lorraine

              Sure I used rennet for the coagulation.
              But as a thermophilic starter I used plain yoghurt which I read in a recipe of my cheese making book. On ehow.com, it is written that we can replace citric acid with lemon juice using four teaspoons of lemon juice for every teaspoon of citric acid. Isn't that right?

              1. re: tcinlarses

                In my opinion, no. Lemon juice is not a strong enough acid. Even ascorbic acid, what I first used to make mozz, is not strong enough. I'd never use it now. And mozz doesn't taste like mozz without lipase.

                1. re: maria lorraine

                  how do you get lipase? i havent seen it in any recipe so far?
                  how is it produced? i mean i know how rennet is produced but havent heard of lipase so far..

                  thanks a lot for your replies btw, i will try both with lemon juice and citric acid, then compare results : )

                  1. re: tcinlarses

                    I'd really advise you to follow a good recipe that contains lipase, genuine TH culture and citric acid. Otherwise, IMO, you're trying to make mozz without the proper ingredients for the chemical reaction.There are many recipes posted and/or linked to in this thread. Lipase is available online and at cheese/beer making shops that carry cultures. Also, read below about UP milk -- it won't work.

                  2. re: maria lorraine

                    Hi Maria,

                    I got some citric acid now.
                    Can you tell me please the ideal proportion? how many grams should i use per liter of milk? and how many drops of rennet?

          2. I'd agree with Maria_lorraine that your lactic acid mixture wasn't enough. Definitely try with the citric acid. I never use any thermo cultures or enzymes in my mozza - only milk, citric acid, and rennet (I usually use tablets) and I never have any trouble UNLESS (and here's my second guess with your first batch) the milk has been ultrapastureized. Check your milk by actually calling the dairy (or dairy collaborative) that produces (or distributes) your milk! Even organic milk can be ultrapasturized, and no matter what you do, ultrapasturized milk will not turn into cheese. Since it's not always properly noted on cartons, you can have UP milk w/out knowing it - as was the case when my mozza started failing last year. I was using the same milk I'd always used, but the dairy had started UP, but hadn't changed their labeling at all...

            Good Luck!!

            4 Replies
            1. re: bflocat

              Wow, thanks for that piece of advice. I will certainly take all of your advice for my next batch - I will master the Mozz!!!

              1. re: SpareRib

                Great thread.

                Report back please!

              2. re: bflocat

                What kind of storbought milk would work? 2%? Here in Alberta we cannot get fresh milk due to a stupid govt regulation.
                I assume homogenized milk is a complete no go.

                Thank you,

                1. re: swisscheese

                  homogenized milk is fine but NOT ultrapasteurized

              3. I can't see this mentioned elsewhere in the very helpful comments from others...

                what milk are you using? I've tried making mozzarella with normal supermarket milk, and it just didn't work; the curds wouldn't firm up, fell apart. Now I always use non-homogenized milk (try a farm or a health food shop), and I don't have a problem.

                1 Reply
                1. re: Gooseberry

                  I'm reading Barbara Kingslover's Animal, Vegetable, Miracle and I'm just at the point where she talks about cheesemaking. She specifically mentiones to check your milk to make sure it's not been ultra-pastuerized.

                2. This link might be helpful. Even my first batch was delicious!


                  2 Replies
                  1. re: smtucker

                    I've made the 30 minute mozzarella recipe on the cheesmaking.com website many times, and it's come out great every time.

                    1. re: smtucker

                      I used this recipe to make mozzarella over the weekend. It turned out ok but I have some questions.

                      When heated to 90 degrees (actually it was closer to 95), it didn't become custard-like as shown in the picture. The top was more like a bunch of curds floating in whey. When I inserted a knife into the mixture, I could feel some amount of tension at the bottom of the pot so there was definitely something I could cut through. So I did, even though it probably wasn't necessary because the whole thing was pretty loose so I don't think I needed to cut it to release the whey.

                      It didn't have much flavor. I'm sure I added enough salt at the end but it just tasted milky and not very cheesy. Even tasted it as I went to make sure I had enough salt. I used good quality organic milk. Should I add lipase for more cheese flavor?

                      How much are you supposed to stretch it? Do you stretch it to the max once, then bring it together or do you stretch, bring it together, then stretch it again? I tried to do the latter but it had cooled too much and I had to microwave it again. Every time I microwaved, it got little grainy patches (hot spots) so I stopped. Anyway, I didn't think the end product was stringy enough. Also seemed like the more I stretched, the more difficult it became to bring it back into a ball and get it shiny.

                      About an hour after eating, my husband and I both experienced a little stomach discomfort. Nothing major and didn't last very long but I'm sure it was from the cheese. We are not lactose-intolerent and have never had problems with store-bought mozz. What could have cause this?

                      Any input would be appreciated as I intend to try it again real soon... and this time I'm going to make ricotta from the whey instead of dumping it.... I had almost a gallon and didn't know what to do with it and no room in the fridge.

                    2. My first attempt was a disaster. It was a gloppy mess that never formed into a distinct solid. In my case the problem was ultra-pastureized milk. According to my recipe, pastureized milk is fine, but not ultra pastureized. However, I later read that milk which is shipped long distances is frequently ulta even when it is not mentioned on the label. I made my second batch with local milk, still pastureized, and it worked perfectly.

                      1. Great read! Thank you so much for the information - hopefully it will set me up for success. Much apprecaited!

                        1. Depending on where you live, it's virtually impossible to make fresh mozz from supermarket milk, because it's all been ultra-pasteurized, even "Organic" milk. You need to find a milk that's been pasteurized at a temp below 160F. There are cheese-making websites that can help you find a market in your area that has such milk. I believe the term you need to search for is "Vat Pasteurized."

                          Nothing I tried worked until I found the right milk. You must start there because without that, nothing else matters.

                          3 Replies
                          1. re: acgold7

                            Here's a link for where to find milk that will properly make mozzarella:


                            This page really explains it all and is fascinating reading:


                            If your mozzarella doesn't set into a silky curd and looks more like grainy cottage cheese or ricotta than a smooth yogurt -- see the pictures at this link:


                            then the milk is likely your problem. I was pulling my hair out until I figured it out.

                            Slight correction to the above: While UP milk is above 191F, any milk that has ever gone above 172F is no good for mozz. No recipe in the world will make it work.

                            1. re: acgold7

                              Mine initially worked quite well with supermarket-brand milk. Then I tried to get fancy and use organic milk - it failed. Then I discovered that organic milk is ultra-pasturized and that was the problem.

                              1. re: sandylc

                                You are so lucky that your markets carry any form of non UP milk. None of the markets in my area do, save one I was able to locate thanks to the list I posted.

                                And as the pages note, even non-UP milk often reaches 172F, which is enough to kill any chance it has of coagulating properly. So if it doesn't specifically say "Vat Pasteurized," or something else that indicates it hasn't gone over 160F, you may be rolling the dice.

                          2. Here is a great recipe that works for me first time, every time:


                            1. Hey SpareRib!
                              Did you ever figure it out? I have the same problem, I believe everything alright until I put it in the microwave, and after that is just a mess. Falling apart instead of becoming strechy....
                              I wonder am i suppose to put thermophilic cuture, none of the recipes mention it.
                              What is wrong?

                              2 Replies
                              1. re: emoke2

                                Nope, never did. I believe acgold7 above hit the nail on the head when they said it's virtually impossible without the correct milk product (at least where I am). In order to get the right milk I would have had to drive 50 miles each way after having ordered in advance. Life is too short to go to that much trouble, even for good cheese! (I can't believe I said that, lol.)

                                1. re: emoke2

                                  I had the same problem with my own raw goat milk from my backyard goat, and the answer turned out to be that the curds needed to be drained MUCH better before I put it in the microwave. So I added the step of pouring the glop into a cheesecloth and hanging it to drain for awhile before I did the heat-and-drain process in the microwave.

                                2. You know I used my own raw goat milk from my alpine doe, and had the same problem - I waited 45 minutes and just got mostly cottage-cheesy looking little curds rather than nice firm tofu-like cubes.

                                  So I said to heck with it, I'm making cheese out of this SOMEHOW, and went ahead with the mozz recipe. No matter what I did to it, the curds stayed a sticky lumpy mess.

                                  But, I was determined that this mess WAS going to become mozzarella SOMEHOW! SO, I kept heating and draining off whey, over and over and over. Instead of twice in the microwave for 35 seconds like the recipe suggested, I must have heated and drained 6 or 7 times!

                                  And viola! Eventually, with the ball of curds losing size every time I heated and drained, I had a little lump the size of my fist that I could actually knead without it breaking apart into a sticky, chunky mass.

                                  While I agree that ultra-high temp pastuerized mlik is probably the problem for a lot of people, I had the SAME list of problems as many other commenters here while using fresh raw unpasteurized unhomogenized organic milk from my own backyard goat.

                                  Which causes me to think that the recipe is probably omitting signs to look for that an experienced cheesemaker would just KNOW - like, they always say "drain off the whey" but that really doesn't tell you how dry and firm the curd should be in order to be considered fully drained.

                                  The next time I tried it, I got curious and once I had heated and drained a couple times I just used non-chlorinated water to WASH the darn curds, just like you would do to wash the butter-milk off of homemade butter.

                                  I swirled the curds around in a bowl of water a few times, poured the whole ugly sloppy mess through a cheesecloth, pressed out the water as hard as I could, let it hang for a couple hours, and THEN did a few more "heat and drain" micorwave cycles before kneading and

                                  Guess what? That technique also made a decent mozzarella. A little bland and rubbery - wouldn't do it that way again unless I was really pressed for time - but doing it that way made perfectly functional mozz.

                                  I had to do the same thing with some whey ricotta because I put in too much vinegar and the cheese curd just tasted in-edibly vinegary once drained.

                                  So I washed the ricotta curds in water - and they immediately dissolved into cheese sludge. I thought "oh noes, what did I just do?" but I went ahead and swirled the mess around and poured it through ultra-fine cheesecloth. Sure enough, the water filtered through & after it was hung and drained, it left a pretty good ricotta - a little grainy and still a little vinegary, but MUCH better than what I was going to end up with otherwise.

                                  So my suspicion is that "won't set up firm" causing you to end up with "sloppy sticky mess" is more fixable than we might have thought :)

                                  If you have a sloppy inedible mess on your hands ANYWAY, I would suggest messing with it and trying to "fix" it, because if nothing else you might learn something about what you did to mess up in the first place.

                                  1 Reply
                                  1. re: CatFury

                                    Awesome advice! I tried twice last night to make mozzarella from store bought milk, citric acid and rennet tablets. We have well water so I used our sink water for dissolving the acid&rennet. No go-I only got mushy slop that I ended up throwing out. Determined I tried again tonight-using bottled water. I noticed larger curds right away during the initial heating up and was very excited to see it starting to thicken up. But after adding the rennet, it never curdled-so instead of throwing it out, I decided to play and see what would have pushed it to curd more-I sprinkled a dash of the citric acid over the top and the curds instantly started to form! I was super excited and finished the process-family loved the cheese.... I do too but feel like I have a little acidic aftertaste... So researching now to find out what I can do to fix it!

                                  2. I realize this is a very old post but perhaps someone will read and have some advise for me. I had the opposite problem of everyone else. I used fresh, raw milk from my cow. I added the acid, warmed the milk, then added the rennet. The recipe said to still up and down for 30 seconds. After 15 seconds it was getting very thick and stringy. I stopped stirring and let it rest for 5 min. The curd was so thick and rubbery I could not cut it. I just picked it up and started squeezing out the whey. Then warmed it it a hot water bath and stretched and formed it into a ball. It was very firm and rubbery. not a great Mozz flavor. what happened?