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Jun 1, 2013 05:10 PM

French fry mishap

After par boiling potato fries I dried them and put them in a spare freezer to cool. It was getting late so I left them overnight. In the morn they had turned blackish. What caused this? Did I not par boil them enough? Was it the freezing? My intent was to par boil, dry, cool and deep fry until cooked but not browned. Then freeze and do the final deep fry the next day for a cook out. Any help would be appreciated.

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  1. I once froze parcooked fries and when I deep fried them the next day, they disintegrated.

    1. I have never heard of parboiling potatoes for fries. Can't imagine there is enough structural integrity left after the dip in the hot water to keep them fry-like.

      2 Replies
      1. re: smtucker

        I didn't parboil, I think I microwaved because I didn't want to bother with the oil for the first cook. I froze because I was going to finish the cook 2 days later. Didn't work.

        1. re: smtucker

          It's really not par boiling. Fries in cold water slowly heated until you get the start of a boil. It removes a lot of starch.

        2. If you are doing a oil blanching what is the par boiling for?
          And why the Freezer?
          Here is an study about after cooking discoloration

          18 Replies
          1. re: chefj

            Thanks chefj.
            I'm after fries with soft not over cooked inside and crispy crispy out side. I read to put them in a pot of cold water and slowly bring them up to a very slight boil. This removes a lot of starch and partially cooks them. Dry and cool. Then a quick dunk in the deep fryer. Dry and cool. Then the final fry. The post said you could freeze after the first fry. I made a small batch and they we great. The big batch not so good.

            1. re: Ronbak


              CI adapted a Joel Robuchon recipe for cold oil frying that eliminates rinsing and double frying. I've tried it and it works great. You need Yukon Golds to make it work.

              Bonus points for no peeling needed and you don't have to stand over a pot of hot oil, avoiding the oil-steam facial.


              1. re: DuffyH

                Very interesting Duf. Do you know what temp they eventually get the fry oil up to or is it just til they look crispy? What would you do if you needed a large quantity and had to several batches?

                1. re: Ronbak

                  Can't fault experimentation. Especially when my immediate response is "what where you thinking of?'

                  I have been humbled so many times before.

                  1. re: INDIANRIVERFL

                    < immediate is "what where you thinking of?'>

                    I often follow that comment by banging my forehead on upper cabinets, which explains both my flat forehead and the loose hinges on the cabs. :0

                  2. re: Ronbak

                    <Do you know what temp they eventually get the fry oil up to or is it just til they look crispy?>
                    When they're crispy, they're done.

                    <What would you do if you needed a large quantity and had to several batches?>
                    Um, er, use two pots? Seriously, multiple pots or one big pot are the only options here. Personally, I'd go for two pots and guaranteed success, although a big stockpot does sound cool. My only concern would be clumped-together fries, but it would be worth it to try.

                  3. re: DuffyH

                    since reading about this method, it's the only way i fry spuds now. i use a high-sided skillet and about 1 cup of oil. i have cut the potatoes different ways and most often use "local" maine or pei spuds. have also used yukon golds and all of them have come out great.

                    no worrying about oil temp, just cook til golden.

                    the potatoes turning black were because they were undercooked and the cells ruptured.

                    1. re: hotoynoodle

                      Thanks noodle! I figured under cooked and cold temp does not a happy spud make.

                  4. re: Ronbak

                    I have never parboiled, and use a 2-step process. First, tho I buy BIG baking potatoes and store them away.usually at least for a month! If they develop sprouts, well, then time to use them, but I like at least 6-8 weeks at home before I cut them.

                    I cut them on the thinish side, leaving the skins. At Noon or around there. Soak them in several changes of water (2 within a half hour after cutting, them maybe more with ice cubes thrown in.)

                    Dried and cooked in "bunches" at 325 until the bubbling subsides, they are then allowed to rest at least a 1/2 hour before final 375 immersion.

                    1. re: FriedClamFanatic

                      interesting, since most supermarket potatoes, throughout most of the year, are already old.

                      1. re: hotoynoodle

                        Yep..........and it just seems to make for a better fry. I have even grown my own.but in that case, I'll keep them 6 mos or longer

                        1. re: hotoynoodle

                          In doing research, I found a NY Times article that talked about a NY restaurant chef who actually paid his supplier to provide him with storage potatoes, even during the time of year they are harvested fresh, and from my experience, it would be for two reasons: (1) if you've ever eaten a fresh, just dug out of the ground potato, they taste incredibly different from your average storebought potato. I actually grew them one year, and it was the most delicious thing I've ever eaten, way better than a homegrown tomato. The skins were so fragile you could peel them off with your finger, and the potato is full of natural sugars, not natural starch. The sugars start converting into starches the minute the potato is harvested, even right from the farmer's market, they don't compare in taste to one freshly dug from the ground; and (2) loss of some of the water content during storage.

                          I didn't try keeping potatoes for 6 - 8 weeks, but I did compare results using big baking size russets and using the much smaller ones you buy in 10 lb. bags from the store, and got much better french fries from the small potatoes, presumably because they have greater water loss than the larger ones (and the fries cut from the exterior sides were always crispier than the ones cut from the interior).

                          1. re: ePressureCooker

                            Most of my home-growns went into new potato recipes, but I always kept a few to linger.and yes.a baked potato that was pushing dirt aside just a few days ago is a true delight

                    2. re: chefj

                      Great article, but can you tell us what Na2H2P2O7 is, and where we can pick up a pint or two> Thanks! '-)

                      1. re: Caroline1

                        Its Disodium pyrophosphate (aka Sodium acid pyrophosphate). Couldn't see anywhere to buy it, but this


                        says its moderately toxic by injestion or subcutaneous methods, although its supposedly a food additive, so perhaps that's why its not being listed for sale under its chemical name. (Maybe called something else if its sold to the public?)

                        1. re: ePressureCooker

                          E, Are you not making your own sodium Acid Pyrophosphate with what you put in your fry par boil pressure cooker recipe?

                          1. re: Ronbak

                            I'd have to ask my friend who's a chemistry professor - its not my personal strong suit.

                            I know that the small amount of alkali starts the chain reaction, which causes the pectin in the cell walls to be attacked, which releases the starch and a second alkali, sodium acetate (CH3COONa), which I learned in my research, is used as an additive in the food industry to improve taste (and coincidentally, to help provide the flavoring for "vinegar" potato chips), but which serves in this case a different purpose, as a second base to break pectin cell, releasing more starch and more sodium acetate, continuing the reaction. I'm afraid I don't know what other by-products are created during the process.

                            That was just a guess on my part that disodium pyrophosphate might be sold under another name to the public. There are lots of things that can be classified as mildly toxic when eaten, but are eaten in such small quantities that the effect is negligible or non-existent. If you ate enough salt at once, it'd probably be toxic, too, possibly fatal. (Actually, I just looked it up, and for babies and small children, for example, eating too much salt at once can cause brain damage and kidney failure:

                    3. I don't know the answer to Ronbak's question re the fries turning black, other than to guess perhaps they weren't cooked sufficiently. But that's a guess.

                      But I will add for those who have never heard of such a thing, yes there are reasons why you might want to parboil your fries before frying them. Actually, if you parboil them in a solution with vinegar added, it actually helps reinforce the pectin that comprises the cell walls, and makes it stronger.

                      I myself actually PRESSURE COOK them first, very briefly, (which, when you use a trivet or vegetable steamer is more like steaming them than boiling them) for several reasons: it gets rid of the not quite cooked interiors problem when you pan fry instead of shallow frying, I can inject salt into the interiors for a tastier french fry, and I also use a secret ingredient (baking soda) to cause a chemical chain reaction which breaks down the molecules in the surface of the potato to produce a crispier crust.

                      I'd post a link to my recipe so you could read the technical explanation, but its on my blog, and I don't know if we're allowed to do that, and I don't want to break the rules.

                      6 Replies
                      1. re: ePressureCooker

                        I've seen outside references here before, so I think it's ok......or at least add to your profile as I'd LOVE to try your version

                        1. re: FriedClamFanatic

                          Okay, some self promoter I am, I didn't even think about that. I've added my blog to my profile (its new, so there's not much there, but I did a helluva lot of taste testing of various methods of making fries.

                          1. re: ePressureCooker

                            Guess what I just added to my favorites! As an owner of several Pressure Cookers that only rarely get used, I'm always on the lookout for something "non-stew" that I can do in them!.......Thanks!!!!!!!!!!

                            1. re: FriedClamFanatic

                              In that case, check out the faux pastrami recipe. I *love* my pressure cookers, I'm always trying to figure out how I can make different things in them. ;D

                              1. re: ePressureCooker

                                Very nice blog and explanation of your method for fries. Pressure cooker just went on my wish list.

                                1. re: Ronbak

                                  Thank you! I'm glad you liked it. Always nice to hear a few kind words.

                                  Definitely recommend pressure cookers. They're WONDERFUL. Can't imagine how I lived for so long without one. We're now eating a lot more fresh beans, fresh grains, brown rice, homemade soups, you can even make jam in them!