Anonymous Modernist 347

I would strongly recommend the inexpensive Sous Vide Dash app for the iPhone and iPad for answering these kinds of questions. I bought an iPhone, just to get that app! It does a detailed calculation based on heat transfer thermodynamics, similar to what Douglas Baldwin based his times and temperatures on. It allows you to specify the starting temperature of the food, the temperature of the water bath, the desired core temperature of the dish, and whether you want to simply raise the surface of the food that the desired level, or to pasteurize the surface, or pasteurize all the way to the core, and then tells you how long to cook it. It even plots the rate at which various pathogens are destroyed. In addition, a recent revision allows you to calculate the cook-chill times, where the food is placed in an ice bath after cooking. Regrettably, it does not yet support one of my favorite cool-down techniques, where I use inexpensive vodka stored in the freezer at -10F, instead of ice at 32F. Obviously, that cools down the food, still in the SV bag, a whole lot faster, and the vodka is reusable, without having to fuss with lots of ice. As I understand it, it isn't all that easy to calculate how much additional time is required to cook something from frozen, because of the latent heat that is required to transform ice into water, and the varying amounts of water that might be present in meat. You can use the tables in MC or in Douglas Baldwin's treatise as a starting point, but be aware that they are just approximations. If it is really important to you, throw the frozen food in the bath, and take it out from time to time until it feels just barely thawed, and then calculate the time assuming a 1C starting temperature.

I have the 25 qt. All American sterilizer, which I adapted to PID control. I holds my 7 liter All-Clad Pasta Pentola pot inside it, so I can cook in stainless steel, rather than aluminum. Seehttp://freshmealssolutions.com/index.php?option=com_k2&view=item&id=71:high-altitude-pressure-cooking-and-stock-making&Itemid=100088.

What does a vacuum tumbler do? I've never heard of one.

I have a concern about the risk of botulism in regards to the garlic confit recipe, and especially the note that accompanied it in the November blog, which stated that "The cook­ing time in this par­tic­u­lar recipe allows for alarge mar­gin of safety, so it can remain at room tem­per­a­ture indef­i­nitely as long as the lid remains sealed. Once opened, the gar­lic con­fit will last about two months, refrig­er­ated (the colder, the better)." The primary recipe uses a pressure cooker, and cooks the garlic in oil at 1bar /15 psi for two hours. That pressure at sea level corresponds to a temperature of 248F, and that is indeed high enough to destroy the spores of Clostridium botulinum in about 3 minutes. But in Denver (5280 ft.), Taos, NM (7000 ft.), and certainly in Bolivia (10,000 ft.), a marked 15 psi will NOT produce that high a temperature. Instead you would need an autoclave, or a sterilizer. In my case, in Taos, I would need 18.5 psi to reach that temperature. But worse yet, the alternate instructions suggest vacuum sealing the confit and cooking it sous vide at 88C/190F for seven hours. That might be sufficient to produce a nice Maillard reaction and a tasty result, but available data suggests that at 205F the time to produce the recommended 10^12 reduction of spores would be over 1000 minutes, or 16.7 hours, so 7 hours at 190F would certainly NOT be enough time. Unfortunately, botulism spores can sporulate and produce the botulism bacteria that makes the deadly toxin, at storage temperatures as low as 3C/37F. So unless you kill all the spores, or keep them from growing through adequate chilling, you run a significantly risk. So please, people, if you live at high altitude, and you use a normal pressure cooker; or if you follow the sous vide instructions, DO NOT consider the garlic confit to be shelf stable, even if the lid remains sealed! Instead, according to the US FDA Food Code, it must be refrigerated at a temperature lower than 1C/34F, and kept for no longer than a month; or else vacuum sealed and then frozen, whereupon it would have an indefinite storage life.

Today/tonight I made the starch-infused ultrasonic French fries from MC, and my wife and I agreed that they were absolutely the best we had ever eaten, bar none! They were deliciously crunchy on the outside, and soft and succulent, rather like a baked potato, on the inside. Even thought the initial cost was about $75 per fry considering the cost of the Branson ultrasonic cleaner, I think it will be well worth it over time. Because I don't have a combi oven, I cooked three potatoes (750 g, divided onto two bags, after brining them) in a big pan in water on the stove, in two SV bags. I then drained them and let them cool in the freezer for about 20 minutes, while I made up the potato starch mixture. I drained the original water mixture and transferred the potatoes to two new bags, and added the potato starch mixture, then put them in the Branson ultrasonic cleaner, which had been degassed and brought up to 64C. After 20 minutes, I flipped the two bags over, and gave them another 20 minutes. I then put the fries on a rack, and put them in my JennAire oven on the dryer function at 100F for about 20 minutes. After that, I transferred the fries to a rack, and put them in my chamber vacuum and ran it it five times at maximum vacuum. Several times it timed out, unable to reach maximum 99% vacuum, so I had to stop and restart it. Then I put them in my Krups Professional Deep Fryer at 330F for three minutes, and afterwards put them on rack in my garage, with an electric fan blowing on them to cool them. Then finally back in the deep fryer at the maximum setting (375F), but unfortunately this isn't quite hot enough. So instead of merely 3 minutes, I had to give the fries closer to 6 minutes to reach a nice goldren-brown color Served with ketchup and Boar's Head Creole mustard, together with two SV lamb shoulder chops, with rosemary and garlic confit, the results were absolutely worth the effort! Bob

Judy said: I recently received a Branson B5510DTH ultrasonic cleaner (2.5 gal), and I want to try the ultrasonic starch infused fries. However, the recipe on 3-325 is a little light on some of the details, so I have some questions: [*]The first step after cutting the fires is to seal them in a salt solution, and then cook them at 100°C. I understand why this might be convenient if you have a Combi oven, but is there any reason why they can‚’t be cooked on a stove top, using an ordinary pan (perhaps an oven roasting pan)? [*]The next step is to whisk together the potato starch and water, and vacuum seal with the potatoes. I assume the potatoes should be in a single layer, correct? Does it matter if they are touching? [*]I bought the perforated pan with the Branson unit, but now it occurs to me that I should have perhaps bought the solid pan. Then I could just put the potatoes in the starch/water mixture, so they could move around. Does the vacuum bag do anything special, other than facilitate flipping it? [*]Step 10 says, ‚“Place the hot fries in the vacuum chamber.” My Branson unit has a heating capability, but how hot is hot? With the cover on, the temperature should reach 62°C. Is that hot enough? [*]I‚’ve had some problem with excessive water vapor contaminating the oil in my chamber vacuum, and for that reason I was thinking about using the convection/drying function on my JennAir oven for the drying function after the boiling step, rather that the vacuum. It will go down as low as 38°C/100°F ”” is that cool enough? If necessary, I suppose I could dry them in the oven, and then pop them in the vacuum for a final drying step. [*]At least one user has reported storing the dried, boiled potatoes in the fridge overnight, and raved about them. Any thoughts?

Judy said: I've done the triple-cooked Heston Blumenthal pommes pont-nuef, and served them with his mushroom ketchupwith great success. However,the recent update from Maxine Billet is going to inspire me to try some of the other variations, including brining the potatoes before sealing them, and the starch infusion process. A couple of comments, however. 1. MC suggest par-boiling the fries for 20 minutes. I find that despite being at 7000 ft, that is too long, the Russet potatoes I use fall apart too easily. I've reduced the time to 15 minutes. 2. Vacuum cooling and drying sometimes makes my chamber vacuum go into an error condition, because it can't reach the 99% level when the fries are still moist. I've had to reduce the vacuum percentage to 95% for the first couple of cycles. 3. For reasons that I don't understand, there isn't an electric deep fryer on the market that will go above 202C/395F. I recently bought the Krups Professional, which does an admirable job of filtering out the grease smell with the charcoal filter, but it doesn't get quite hot enough. However, getting out a Le Crueset pan and doing it on the stove top without a thermometer is just too much of a pain, so I end up cooking them a little longer on the second fry step. 4. I'm presently using Crisco vegetable oil rather than the peanut oil I used to use. I filter the oil after each use, using a paint filter from the hardware store with a cheesecloth-like gauze filter at the bottom to get with of any residue. A coffee filter was just too slow. Now a question/challenge for the MC staff: Dow Chemical, in their Product Selection Guide for METHOCEL Food Gums (http://msdssearch.dow.com/PublishedLiteratureDOWCOM/dh_04f6/0901b803804f6660.pdf?filepath=/194-00001.pdf&fromPage=GetDoc), page 8, recommends METHOCEL A15 FG or E19 FG at a 0.5-2.5% use level for "French Fry Dipping Solutions." The benefits are said to be that Thermal gelation reduces batter blowoff (whatever that might be), and extends the life of cooking oils; and freeze/thaw stability helps prevent batters from cracking and loosening on frozen foods. Has anyone tried methylcellulose for such an application (I haven't)? Would it only be useful when making frozen french fries for commercial use? How about when making the starch-infused fries? It appears from the cartoons above the text on that page that it should be useful for "Krispy Fries" and also fried shrimp. Bob

The Cooking Issues article by Dave Arnold cited by Joe is quite comprehensive. In particular, the Arizona State University PDF on cryogenic safety should be required reading for anything thinking about using LN2.Cf.http://ets.fulton.asu.edu/files/shared/CryogenHandling-FSE.pdf. I recently had the tasting menu luncheon at the famous Eleven Madison Park in NYC, and during the meal they took me back into the kitchen where they fixed an "edible cocktail" made with LN2 ice cream, some diced apples, and some pomegranate juice (I think). While delicious and impressive, I was shuddering the entire time because their very casual attitude towards safety. The woman who was preparing the "cocktail" was wearing a cotton chef's apron over her clothes, had no gloves or goggles, was handling the ice cream in what appeared to be an insulated Dewar with her bare hands, and was stirring the ingredients with a metal spoon, stll with her bare hands! Good Grief, people!

Judy, just so someone doesn't misunderstand you, you must NEVER, NEVER, EVER screw the lid on tight on a Dewar or other container of liquid nitrogen, e.g., a Thermos of it, whether you are transporting it or otherwise. A liter of liquid nitrogen will turn into 700 liters of gaseous nitrogen as it vaporizes, and that is enough to cause a very serious, concrete-busting, room destroying explosion. For this reason, Dewars may have a small lock on them to prevent misuse, but they do not have a tight screw-down lid. Instead, they are explicitly DESIGNED to leak, safely, albeit slowly. For that reason, don't store the Dewar is a tightly closed room, and certainly not in something like a walk-in refrigerator. You might not be able to walk out again!

You should certainly download Douglas Baldwin's excellent Practical Guide to Sous Vide Cooking, atwww.douglasbaldwin.com/sous-vide.html. He has extensive tables, scholarly references, etc., that should help you with your arguments.

My Waring Pro deep fat fryer was only reaching 340F when it was set at 375. So I took it apart, found a calibration screw on the inside, and calibrated against a high-quality digital oven thermometer. Now, however, it is way off at the lower end, reaching 195F when set at 175F. Worse yet, when I turn it up to 375 it gets up there, but then apparently goes into a high temperature shut-down and won't work at all. Does anyone know of an electric fryer that will go higher than 375F, ideally to 425F/200C, and at the same time is reasonably accurate? Otherwise, I might be inclined to short out the thermostat on this one, and adapt it for use with a PID controller, if I can find a suitable9 high temperature sensor.

LFMichaud said: Yes, according to the pressure gauge, 25 psi should equal 130C at sea level. The only modification was to unscrew the pressure relief valve,and then screw it back into a T-adapter of the same thread type. Then I threaded two sensors through a brass cap that I had drilled out, filled it with epoxy, and screwed it onto the T. I"m contemplating removing the pressure relief valve entirely and capping it, relying on the PID controller to keep things from getting too hot and blowing the secondary relief plug. But that would mean that I could no longer vent the hot air until it turns to steam, which is highly desirable for canning and the intended use for sterilization, although venting isn't recommended for making stock. Maybe I can find higher-pressure relief valve somewhere.

The short answer is NO. If the Nitrogen should leak out ' maybe the Dewar could fall over if you are involved in an acci­dent the nitro­gen will boil quickly to make nitro­gen gas and this will dis­place the air in your car and you will suf­fo­cate ' not agood idea. You can trans­port liq­uid nitro­gen either in the boot (US trunk) of the car only if it has asep­a­rate sealed bulk­head ' not in acar with fold down rear seats. It is best to use avan (US truck) with asealed rear com­part­ment or atrailer. You should inform your insur­ers that you will be trans­port­ing liq­uid nitro­gen (oth­er­wise you may find your insur­ance is inval­i­dated) and you should dis­play acryo­gen in tran­sit yel­low warn­ingsign.Thanks, Peter. I was aware of the asphyxiation hazard, and had planned to drive with the windows open. Unfortunately, my SUV doesn't have a separate trunk, although I guess I could put it on the roof. But never in a million years would I have thought to talk to my insurance company, or display a HAZMAT sign. This was for a class in Modernist Cuisine I am planning to teach in Santa Fe, about 60 miles away, but all things considered, it just isn't worth it. Now a question for you and Joe Lipinski. Are you using liquid nitrogen as part of your modernist cuisine cooking, or are you just familiar with it from your occupation, e.g., a dermatologist of something? I've been thinking about starting a thread on liquid nitrogen techniques and recipes on eGullet, in part because the Cooks Forum doesn't seem to be very widely read. But if there is any interest, I suppose we could start one here.

It seems to me that 135F is going to be medium. I wouldn't go above 131F (55C), or even lower (52C) if you like it on the rare side. Second, the grinding technique is apparently important. See MC 3-234. And don't vacuum seal (or use a very low setting) -- instead use a ziploc bag and the Archimedes principle to avoid compressing the burger. If you don't have any liquid nitrogen, you could try dunking the bag with the burger in a bath of alcohol (cheap vodka) and dry ice. If you don't pre-chill the meat, deep frying it is probably going to overcook it, depending on the thickness. But all of this sort of contravenes the precision of sous vide cooking at a specific temperature. How much nitrogen, for how long, how thick were the burgers, how hot was the oil,and for how long??? Is it necessary to chill the burger to 0F, -30F, -60F, or all the way down to liquid nitrogen temperature? Who knows!

You might want to look at my post regarding High Altitude Pressure cooking and Stock Making, in the equipment section. I haven't made the onion soup, but I did make the potato consummé that is featured in the sidebar. I haven't tried it yet -- it's in the refrigerator. I'm planning to try some reverse spherification sour cream and chive balls to float in the consummé.