Jump to content
  • Welcome to the eG Forums, a service of the eGullet Society for Culinary Arts & Letters. The Society is a 501(c)3 not-for-profit organization dedicated to the advancement of the culinary arts. These advertising-free forums are provided free of charge through donations from Society members. Anyone may read the forums, but to post you must create a free account.

Sous Vide: Recipes, Techniques & Equipment (Part 5)


mjc

Recommended Posts

anyone have any experience with sous vide mushrooms?

i'm thinking specifically about rehydrating a batch of assorted dried wild mushrooms in some stock/butter/seasonings while bagged, and cooking it at the same time as rehydrating. The idea would be to add minimal liquid to rehydrate and allow cooking, and maximize flavor.

anyone have any experience with this? or even fresh sroom's sous vide?

Link to comment
Share on other sites

Hi everybody!

True or not...there is a site that has announced some days ago launching mid August an immersion circulator designed and manufactured by an unknown trademark: Addélice. Their site is not talkative about their product but they said it will be price competitive compared to similarly immersion circulators available on the market.

Wait and see...

Jean-François

http://www.Sousvidecooking.org a blog about cooking sous vide with low and constant temperature.
Link to comment
Share on other sites

...

Searing the outside first is always a good move safety wise.    Or if you don't want to sear, plunge meat into boiling water for 10 sec.

...

For the avoidance of doubt, Nathan, are you suggesting 'naked' or 'bagged' boiling?

And doesn't this crop up again with comminuted meat products, where the 'outside' ends up inside?

For the pre-sous vide blanching you should do it naked. You could do in the bag, but some SV bags get soft at that temp.

Comminuted (i.e. tenderized, ground, jaccarded) has already had inside and outside mixed, as you say. So there is not that much point in pre-sear or pre-blanch...

Nathan

Link to comment
Share on other sites

If it's a sour taste, the likely culprit is some form of lactic acid producing bacteria (eg. Leuconostoc, Pediococcus, Lactobacilli). These are an anaerobic bacteria which grow when oxygen supply is limited and carbon dioxide increases (such as in vacuum packaging).

....

Bob

I think that the lactic acid process started prior to cooking. It might have continued a bit after cooking, but the lactic acid and other spoilage bacteria products then stayed in the bag and ruined your meat.

Without lab tests we'll never know.

I do flat iron steak all the time up to 48 hours.

Nathan

Link to comment
Share on other sites

Nathan, is the book close to publication?

Alas, we kept getting ambitous, so no the book is not close to publication yet. We are working away - there is a team of 6 people working full time on the book. I don't have a firm schedule yet, but will certainly post to the thread when we do.

Just a suggestion for indexing once you finish: It might be handy to have a main component cross reference by temperature, and another by time. It would simplify making a menu based on complimentary techniques.

Stu

Thanks for the suggestion! I'll see what we can do.... the book is large and we have a lot of recipes so a full cross index like you suggest might be unweidly, but perhaps not, I will try it...

Nathan

Link to comment
Share on other sites

Has anyone else noticed a smell coming from a sealed FoodSaver bag?

When cooking turkey breasts seasoned only with salt and pepper I usually notice a peppery aroma. I doubt water has ever entered the Foodsaver bag. Although the aroma is pleasant, I have some concern about it. My daughter in law, a chemical engineer with kids, has practically ridded her home of clear food containers due to her understanding of soft plastics.

Is there another thread where this stuff gets more discussion?

Hampton

Link to comment
Share on other sites

On a couple of occasions I have noticed a sour smell in the case of some meat that had gone bad, and others have reported smells like cloves, etc., apparently escaping the bag.

I don't THINK that fluids are flowing into or out of the bag, but I can't prove it, since there is some "juice" in the bag at the end.

In addition, I've noticed that the bag never seems quite as tightly wrapped around the meat at the end of the process, even once it cools.

So I don't think we can completely rule out the possibility that the FoodSaver bags are semi-permeable to either fluids and/or gasses, particularly over a long time.

IFF that is true, it certainly suggests that every sous vide cooking session should begin with fresh, clean water -- something that I haven't always done, because of the awkwardness of draining the rice cooker.

BTW, has anyone tried using an electric canner, rather than a rice cooker? I've seen one with a drain spigot that would be very useful. I've also seen an electric turkey fryer with a drain.

Link to comment
Share on other sites

IFF that is true, it certainly suggests that every sous vide cooking session should begin with fresh, clean water  -- something that I haven't always done, because of the awkwardness of draining the rice cooker.

This is always a good idea. Water is cheap enough that you really should use fresh water on a daily basis. It is possible to get away with re-using water (and I have done that myself), but why risk it for utterly trivial cost.

Nathan

Link to comment
Share on other sites

Hi:

I recently upgraded to a Polyscience inmersion circulator. It works like a charm, but I've noticed that some sediment has begun to stick to the stainless steel coils... The manual suggests that the water is too hard and recommend cleaning often but it doesn't suggest how... Has anyone had this type of problem with yours? How do you clean it?

Cheers!

pw

Link to comment
Share on other sites

Per advice from Polyscience I use a product called CLR, available at any ACE Hardware store and usually most grocery stores. It works great. I usually only need to clean it every few months when I notice things start to look "grungy"

I usually use a smaller reservoir such as a 7 liter Rubbermaid polycarbonate food storage container for the cleaning process in order to reduce the amount of CLR necessary. My normal tank for the Polyscience is a 20 Liter stockpot from All-Clad.

Hope this helps.

Link to comment
Share on other sites

I've had good luck using a crappy glass vase to hold the cleaning solution. Couldn't be more than 1.5 liters. All you need is something large enough to contain the apparatus of the circulator. It's worth noting that you can re-use the CLR solution.

--

Link to comment
Share on other sites

anyone have any experience with sous vide mushrooms?

i'm thinking specifically about rehydrating a batch of assorted dried wild mushrooms in some stock/butter/seasonings while bagged, and cooking it at the same time as rehydrating. The idea would be to add minimal liquid to rehydrate and allow cooking, and maximize flavor.

anyone have any experience with this? or even fresh sroom's sous vide?

I did fresh Brown Clamshell mushrooms and was -not- happy with the result. 182 for about 15 minutes. Very slimy texture, none of the yummy brown carmelization from pan frying. Mushrooms are off my sous vide list as a main ingredient, though I think dried ones might be nice in the bag to flavor something else.

Link to comment
Share on other sites

Heartsurgeon, I assume that the problem with the fresh mushrooms was that they contain lots of water, which boils off when you sauté them. Since you had them in a sealed bag, the water had no place to go, ergo the slimy result. This suggests that you could use dried mushrooms, but then, how would you rehydrate them? I'm not sure whether butter only would be sufficient, but maybe a tomato sauce would be.

But this bring up another thought. Recently I was trying to make onion marmalade a la Jean-Georges Vongerichten, but I neglected the pan a bit too long while trying to caramelize them, and ended up with sticky, burnt mess.

So I've been wondering whether it would be possible to do this sous vide, taking advantage of the lower and more precisely controlled temperature. Then I realized that I don't really know what goes on when caramelizing something like an onion (or a mushroom, carrot, etc.), the essential role that sugar plays(?), or even what time/temperature is required.

I've looked though most of Molecular Gastronomy, by Herve This, but I don't recall reading an explanation. I do understand that caramelization is different from the Maillard reaction, although Douglas Baldwin's technique of brushing a steak with glucose before searing with a torch may blur the distinction.

Conceivably, at least, if higher than boiling water temperatures are required I could do sous vide in oil, in my deep fat fryer, although I'm not about to put an SVM probe into hot oil.

This also brings up a question as to the essential difference between sautéing and frying, if any.

Has anyone tried this, or can someone explain the fundamental principles involved?

Link to comment
Share on other sites

Carmelization is well understood- it is the oxidation of sugars. Different sugars oxidize at different temperatures. All you need is sugar and heat to carmelize. Since it is partial oxidation, there is always a risk of going to far to complete oxidation - i.e. burning.

Maillard reaction involves a reducing sugar and an amino acid. It is related to, but somewhat different than, carmelization. In many food contexts both carmelization and Maillard reaction are going on simultaneously.

Because the term "carmelized" sounds delicious, it has become popular to the point of over use in cooking discussions. This is especially true restaurant menus. Often the "carmelized" item is at least partly browned via Maillard, but you don't find "Maillardized" on many restaurant menus however.

And just to be gross for a moment, the reason that most soils, compost and excrement are brown is because of Maillard reactions.

Yes, you could use a water bath to control either carmelization or Maillard reaction browning. The temperatures are above boiling point of water so you either need to use a very high pressure autoclave, or you need to work with oil.

Oil will work fine in most "water" baths - in that case you are using it as a very accurate deep fat fryer.

However, the bags normally used for sous vide won't work - they melt. Even high temp retort pouches melt.

Precise temperature control from a "water" bath with oil is helpful in some browning tasks, but not as much as you might think. Because the temperature is above boiling point of water, you must watch it to prevent burning. It isn't a "set and forget" operation like sous vide cooking often is.

The difference between saute and deep fat frying is that the latter using sufficient oil to submerge the food, while in saute it is a film that acts to aid heat transfer from the pan to the food. The food is typically only heated from one side at a time, while deep fat frying involves immersion.

Nathan

Link to comment
Share on other sites

anyone have any experience with sous vide mushrooms?

i'm thinking specifically about rehydrating a batch of assorted dried wild mushrooms in some stock/butter/seasonings while bagged, and cooking it at the same time as rehydrating. The idea would be to add minimal liquid to rehydrate and allow cooking, and maximize flavor.

anyone have any experience with this? or even fresh sroom's sous vide?

I set my unit to 182 degrees and separately vac'd a bunch of veggies and tossed them in. I think I wrote before that I wasn't impressed by any results, except for the mushrooms. They compressed almost like marshmallows, and after 45 minutes (I don't think exact time is too important here) they were great. They were highly flavored, a bit angular because of the pressure, and rendered a flavorful juice. Next time I would do a lower vacuum.

Dried mushrooms sort of scare me from a bacteria viewpoint, but there really is no need to sous vide, I think. The rehydration can be done as boil-in-the-vacuum bag, since the rehydration is really the only point of the exercise. I do this in a microwave in an open container covered with plastic wrap. It might be a little dicey drawing a good vacuum with all the liquid unless you froze it first.

Link to comment
Share on other sites

  • 2 weeks later...

Question about precision of immersion circulators.

I am trying to compare immersion circulators available on the market and most of the trademarks are talking about temperature stability. For example Polyscience on its main page indicates for 7306C stability +/- .09°F +/- .05°C but I don’t think this is relevant. What is the point being +/- .09°F +/- .05°C stable if your are not at the right temperature. I read that measuring temperature in general was a major issue and to reach a precision of 0.3°C you need exceptional and expensive equipment. What is therefore the technical criterion to look at temperature precision in order to compare immersion circulators?

Jean-François

http://www.Sousvidecooking.org a blog about cooking sous vide with low and constant temperature.
Link to comment
Share on other sites

Jean-François, if you'll PM me with your e-mail address, I'll send you a slide deck that I used in a recent class that discusses these points and others.

In it, I argue that absolute temperature accuracy becomes increasingly important as you get closer to the magical 127.5F/53C point of pasteurization. FDA Guidelines set 131.5F/55.5C as the lower limit, at least for commercial food preparation, to allow at least some leeway. In addition, there is an observable difference in the degree of doneness at or around that temperature, but that is a relative, personal choice issue.

For me, I consider 1 degree F or 0.5C to be the upper limit of tolerable accuracy in a thermometer, and I won't recommend one that is off by more than 0.1F or 0.05C at four different points, at 100, 130, 160, and 190F. Many are advertised to meet that standard, but only a few actually do meet it in practice.

Assuming that you have an accurate thermometer with which to calibrate your immersion bath, its absolute accuracy isn't all that important (because you can make a mental adjustment if necessary), but repeatability and stability certainly is. You don't want the temperature to oscillate wildly when you drop is some cold or frozen food -- in particular, you don't want it to overshoot by more than 1F or 0.5C, especially if you have something else in the bath at that time.

Almost any controller, including the inexpensive PID controllers, should be able to hold the temperature within 1F/0.5C. My Sous Vide Magic 1500B (which supports fractional degrees Celsius) routinely holds the temperature to within 0.1C, once everything has come to equilibrium.

Bob

Link to comment
Share on other sites

Question about precision of immersion circulators.

I am trying to compare immersion circulators available on the market and most of the trademarks are talking about temperature stability. For example Polyscience on its main page indicates for 7306C stability +/- .09°F +/- .05°C but I don’t think this is relevant. What is the point being +/- .09°F +/- .05°C stable if your are not at the right temperature. I read that measuring temperature in general was a major issue and to reach a precision of 0.3°C you need exceptional and expensive equipment. What is therefore the technical criterion to look at temperature precision in order to compare immersion circulators?

Jean-François

Both are important.

Stability is important because many temperature controlled devices have large swings - for example Combi-Ovens typically have swings of several degrees C. This makes it impossible to hold to a constant temperature.

When a vendor quotes stability they usually mean for one sensor - typically the water inlet for the circulation pump. A second kind of stability is that within the tank there can be variation in temperature. In a stirred, pumped or circulating bath this variation is minimized, but it is never zero. In an unstirred bath it can be quite large, hence reasons to stir (including with an aquarium air pump in an improvised set up).

Accuracy is also important of course. However, stability is a property of the machine that you can't really change (without changing the PID controller and/or the heating element). Meanwhile every water bath lets you calibrate the sensor if it is off.

Of course you want both accuracy and stability for precise work. With swings of +-5C, it hardly matters what the accuracy is. With 0.1C swings, accuracy becomes much more important.

Nathan

Link to comment
Share on other sites

Bob,

Thanks for your answer. I'll be pleased to receive your document (info((a))sousvidecooking.org).

By the way I found a very interesting information on polyscience site http://www.polyscience.com/lab/7306.html

Down the page is indicated "*Temperature range and stability vary depending on bath volume, surface area, insulation and type of fluid.

Notes: Performance specifications determined at ambient temperature of 20ºC/68ºF."

I understand "temperature range" = "temperature precision".

Should we also have to conclude that Polyscience machine cannot assess the quantity of water contained in a container, the ambient temperature...and therefore Polyscience can't guaranty temperature precision?

Jean-François

http://www.Sousvidecooking.org a blog about cooking sous vide with low and constant temperature.
Link to comment
Share on other sites

Down the page is indicated "*Temperature range and stability vary depending on bath volume, surface area, insulation and type of fluid.

Notes: Performance specifications determined at ambient temperature of 20ºC/68ºF."

I understand "temperature range" = "temperature precision".

Should we also have to conclude that Polyscience machine cannot assess the quantity of water contained in a container, the ambient temperature...and therefore Polyscience can't guaranty temperature precision?

Jean-François

The heat loss from the bath depends on the factors cited above. If the heat loss is too large then the bath won't perform as well.

Most water baths are limited to 1800 watts because they use a standard 20 amp electric circuit. This is much less powerful than an electric stove. If you have a high heat loss rate, or too large a bath of water, it won't be able to keep up.

In practice, precision is rarely a problem. Most waterbaths, including Polyscience, will be quite accurate at normal sous vide cooking temperatures. It is important to cover the bath (with a hard cover, or with saran wrap) to stop evaporation - that can cause both large heat loss, and also cause problems if you run out of water.

Temperature precision and accuracy are a much bigger problem with combi-ovens, which are nowhere near as accurate or precise as a waterbath. They are still OK for most sous vide cooking but you must watch the calibration carefully.

Nathan

Link to comment
Share on other sites

Down the page is indicated "*Temperature range and stability vary depending on bath volume, surface area, insulation and type of fluid.

Notes: Performance specifications determined at ambient temperature of 20ºC/68ºF."

I understand "temperature range" = "temperature precision".

Should we also have to conclude that Polyscience machine cannot assess the quantity of water contained in a container, the ambient temperature...and therefore Polyscience can't guaranty temperature precision?

Jean-François

Jean-Francis

I have a Polyscience immersion circulator. It usually is used in a 20 Liter All-Clad brand stock pot. I have the stock pot wrapped with about 1/2" (12MM) bubble type aluminized insulation. The top is covered with a 1/4"( 8mm) plexiglass sheet that I cut out to fit tightly around the Polyscience circulator in order to reduce evaporation water loss. I have run this unit for at least 24 hours without more than 1/2" (12mm) water level loss.

The Polyscience circulator easily maintains 90C in this water bath. ( the highest I have used so far.)

I have tested the temperature variations in the water bath using a Thermoworks Microtherma 2 thermometer and find the temperatures within .5C in all locations.

I think that my water bath is probably larger than is typical but my results seem to confirm the capability and accuracy of the Polyscience immersion circulator. I do feel the larger mass of water makes the whole system much more stable. For example dropping a 2# (approx 1 kilo) frozen pot roast into the bath never drops the temperature more than .5C and that is for just a few minutes.

The unit is so dependable that I never hesitate even the longest (up to 48 hours) cook times.

I hope my observations are helpful.

Phil

Link to comment
Share on other sites

"I understand "temperature range" = "temperature precision".

Should we also have to conclude that Polyscience machine cannot assess the quantity of water contained in a container, the ambient temperature...and therefore Polyscience can't guaranty temperature precision?"

I do not think that temperature range = temperature precision. The polyscience circulator (all circulators for that matter) have some upper limit of the volume of the liquid they can heat to a given temperature. For example no immersion circulator I know of can heat a million liters of water to 99 C. As for the precision (or repeatability of measurement) I can say that my polyscience (and laudas and some other immersion circulators I have used) is quite precise by multiple comparisions of its stated temp to that of several external thermometers.

By your previous posts you mention something about being at the "correct temperature." I think you mean accuracy. Again with external devices I can safely say that the polyscience is quite accurate as well. At least to the needs of any amateur (and many, many professional) chef(s).

I also do not see why an immersion circulator would need to know the volume of the bath or the air temperature to work properly....it is the temp of the cooking fluid that you want to control and maintain. Even 3-4000 dollar circulators used for scientific purposes do not take into account air temp or need to "know" the amount of liquid in the bath (please correct me if I am wrong). In any instance there is some level of error that has to be accepted.

Any immersion circulator (for cooking needs) such as Polyscience, Lauda, etc. should have more than enough accuracy and precision to work. I do not think that control down to .001C is really needed to produce excellent results.

I hope I haven't been rude...just a long day of research....and I do really hope this helps in some manner.

Cheers

Link to comment
Share on other sites

I do not think that temperature range = temperature precision.  The polyscience circulator (all circulators for that matter) have some upper limit of the volume of the liquid they can heat to a given temperature.  For example no immersion circulator I know of can heat a million liters of water to 99 C.  As for the precision (or repeatability of measurement) I can say that my polyscience (and laudas and some other immersion circulators I have used) is quite precise by multiple comparisions of its stated temp to that of several external thermometers.

The issue is the effect of time on the tuning parameters of the controller. When I put my 1KW circulator in the regular 10 liter bath, it responds quickly in a 0.4 degree F range. When I mount it in a large poly cooler (~50 liters) it is much slower and reset functions cause greater over and under shoot. There is no problem heating a million liter bath, if your insulation is adequate.

Paul

Link to comment
Share on other sites

I would love to see this insulation...how large of an R-value?

I'm surprised that your circulator does not stabalize with a large amount of water in an insulated container. One would think that the thermal mass would prevent a great amount of under and over shooting. Perhaps the PID on your device is having some issues?

Link to comment
Share on other sites

I do not think that temperature range = temperature precision.  The polyscience circulator (all circulators for that matter) have some upper limit of the volume of the liquid they can heat to a given temperature.   For example no immersion circulator I know of can heat a million liters of water to 99 C.  As for the precision (or repeatability of measurement) I can say that my polyscience (and laudas and some other immersion circulators I have used) is quite precise by multiple comparisions of its stated temp to that of several external thermometers.

The issue is the effect of time on the tuning parameters of the controller. When I put my 1KW circulator in the regular 10 liter bath, it responds quickly in a 0.4 degree F range. When I mount it in a large poly cooler (~50 liters) it is much slower and reset functions cause greater over and under shoot. There is no problem heating a million liter bath, if your insulation is adequate.

Paul

Paul - yes, of course the same 1KW of power will take much longer to heat 5X the volume of water, and that mass of water will take much longer to cool - so it's slower to respond in general. However, if tuned properly, your circulator should not overshoot or undershoot much more than normal. Do you autotune it each time you change bath sizes? In theory, every time a parameter changes, (i.e. the bath size changes, or you add insulation to the bath, or you decide to cover it when it was tuned uncovered, etc., ) you should re-tune your circulator parameters, otherwise, it will use the same parameters for all situations, which is not a good fit. Or, if you constantly alternate between a couple of situations, you should autotune each and copy down the settings. That way, when you change situations, you can just enter in the new settings as opposed to running a lengthy autotune every time.

Link to comment
Share on other sites

Guest
This topic is now closed to further replies.
×
×
  • Create New...