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Bernie

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Everything posted by Bernie

  1. Just an outsider view, not about cooking. A few years ago i was investigating heat pipes as a way to cool small chambers for medical research. Basically we needed very low noise (electrical) so having heating/cooling elements away from the chamber is a good isolating method. After investigation, heat pipes would sort of do the job, BUT they have to be specifically designed for each job. Basically the liquid to gas phase change of the fluid (which is how the heat is transferred) is the most important design consideration. Whatever the fluid used it must undergo phase change within the hot & cold ends of the tube. So the fluid is super important . BUT more important is the temperature of each end. The "cold" end for instance must be at or below the temperature for phase change, the hot end must be at or above the phase change temperature. So a heat pipe is restricted to specific temperature ranges. The way to get around this is to mix several different fluids each fluid operating in specific temperature ranges. If you think that is easy then you need to consider what happens when a liquid turns to gas, the pressure increases and hence so does the subsequent phase change temperature. It can be done. For cooling or heating in specific heating ranges they work fairly well (like cooling semiconductors where the final temperature can be set and the cooling power can be continuously adjusted to keep the amount of cooling happening. I am pretty sure the heat pump would work pretty well to heat from cold to a specific temperature but that temperature would usually designed into the device and is probably not alterable. Having said that, if you desired your roast to reach say 60C then you could design the heat pipe device to operate to 50C and the roast would get there much quicker but above its design temperature it would only heat up in the normal way, the heat pipe would just not be doing anything above its design temperature. (I actually didn't use the heat pipe, i went to peltier cells since they are effectively fully adjustable by means of current control) As a final note, there is probably a reason why they are not common place and widespread, more to do with the tight tolerances needed in manufacture and the expectation of consumers that they operate over wide temperature ranges.
  2. I think that it is because the sweet potatoes cook in about half the time of the other spuds. When they cook in liquid, they also seem to become watery with even small overcooking. Pumpkin seems to do the same thing. Not sure whether they start to absorb water or the water starts to break down the cells. When you cook them in the microwave (by themselves in their skins or a plastic bad/container) they tend not to become watery. I roast them in their skins in the oven till the skins are quite dry and the flesh remains intact though soft. Perhaps try par boiling the spuds for 5 minutes. But it might mess up the flavors from the other ingredients or the thickening provided by the starch.
  3. I have tried a couple of recipes for lamb shanks converted to SV. One was a "Morrocon" spice blend. One was a "Rogan josh" What I found was the lower heat does not convert the spices correctly. Perhaps the proportions needed to be changed. What I ended up doing was to cook the spices separately and then add them to the SV bag along with the lamb. The end result was only just OK but not what I was aiming for. In normal cooking I think the lamb liquid and fats are combined in the sauce and the sauce is reduced in the process. With SV the temperatures are such that that doesn't happen and although I could reduce the sauce afterward it means the lamb has not been cooked in the final sauce. Perhaps if i was to long cook the spices separately but adding something like fatty lamb cutlets and then remove the meat/bone then use the resultant sauce to SV the lamb. For normal lamb roast I now just slow cook (2.5 hrs) in a sealed oven bag with rosemary sprigs at lowish temperature (140c) in the oven and open the bag for the last 15 minutes and increase temp to about 170c to harden/dry the outside (not crisp) have found this to be excellent. Depending on the lamb 2~3 days may well be too long; you may get too much rendering of the fats and juices and the meat itself may be a little dry. If its a young tender lamb then it will not need the time but a old worn out sheep may need the brick treatment (brick treatment: cook the meat with a brick. When the brick is tender, throw the meat away and eat the brick 😀)
  4. actually deep frying (as in when the oil/liquid is hot enough) it is the gas surrounding the food that does the cooking. The bubbles formed when we heat anything with water in it (most food) the water turns to steam and that steam as it boils away from the surface of the food does the cooking This steam becomes hotter, heated by the oil to well above waters boiling point and expands (the laws of physics says so) but it rises to the surface of the oil and dissipates as steam. The oil is bubbling & boiling! (well no it isn't the water in the food is boiling - take the food out the oil stops bubbling) So round the food is essentially a layer of super heated steam which does the cooking Once the food runs out of water or there is sufficient crust formed then the oil may well contact the food and the food will absorb some of the oil, though if the remaining steam can't get out past the crust. oil will certainly not go into the food. Once the water is fully used up the food is likely inedible anyway. The heat transfer is conduction (even though the air/steam is moving the heat is being transferred from the gas to the food and the gas is moved on by gravity (it bubbles to the surface) and is replaced by new hotter steam. That is not convection Convection occurs when the medium circulates around a body because of differences in the temperature of the medium itself, which is not what the gas/oil does. There IS convection happening while the oil is being heated but that is within the oil itself. If the oil is not hot enough to boil the liquid in the food then the oil may well be absorbed. (confid?) The heat transfer is conduction. In an air fryer the air itself takes the place of the oil but the food will still have a layer of super heated steam at its surface. In boiling foods the water/liquid and the internal water of the food are at close to the same temperature and there is no super heating of any steam so the heat is transferred directly from the water to the food. The method of heat transfer is mostly conduction. Below boiling the heat is transferred by conduction (in SV the bag is just a moisture barrier not a heat barrier) But it really doesn't matter as long as the chips cook😀
  5. I agree. It's like when you were a kid and you heard the first rumors about father christmas.
  6. Bernie

    Superbowl 2022

    In keeping with the topic (food for the superbowl?)... I watch a lot of games and love the spectacle and the subtleties of the game. But I have not grown up with it and only make token efforts to make it a special occasion event. The super bowl has become a spectacle in its own right and it seems to me they also play football as well.. So.. In keeping with the need to do something to mark the occasion I thought long and hard as to what to do Well the only thing I could come up with was to change from single malt whiskey to bourbon on my breakfast cornflakes. (only for the one day you understand 😁) I rather like the Bengals but I would have liked some of the exciting quarterbacks that didn't make it
  7. Bernie

    Brining Chicken

    I have brine & cooked chicken following Heston's method. Basically the chicken is cooked over a long period of time below boiling point. The brine is to increase the moisture in the chicken. The brine I used imparted a slight salty taste, not unpleasant but noticeable. The chicken was super juicy and melt in the mouth tender. The texture and mouth feel bears no resemblance at all to the traditional ways of roasting chicken. As for scallops (https://en.wikipedia.org/wiki/Scallop ) (there are many different types and substitutes) I was involved in the harvesting and shelling of wild scallops and can say unequivocally that fresh scallops will absorb about their own weight in water. This dilutes the flavor but has the advantage that it increases the weight (they are sold by weight 🙂) BUT if you leave them on a plate or rack in the fridge (or the bench) the water will drain out of them taking some of the flavor with it. Not sure if that also occurs for frozen scallops, I assume they would be the same. One indicator is that the meat of the scallop is nice and white when lots of water has been absorbed. They are usually a dull white when first shelled. Retailers love nice and plump and white because they look good and more importantly weigh more. On display they will nearly always have a good deal of liquid in the dish/display case. This is to keep the plump and is actually what has come out of the scallops.
  8. I make white sauce as a starting point for quite a few different dishes. I have always done it "by ear". Flour, Butter, Milk (or liquid). Probably as most do I sort of know how much of each and then I sort of trial and error to get the right consistency I need. For fairly plain sauce I add nutmeg. It takes away any blandness I sometimes get particularly if I am not adding salt to the finished dish. Method I now use is to heat the butter and stir in the flour to make the roux. Then I take it off the heat allow to cool and then heat the liquid in the microwave then add to the roux stirring with an egg whisk When dissolved and smooth, return to the heat and still using the whisk bring it to the boil (or close to it depending what I am going to use it for). Does anyone have any hard and fast rules as to the ratios. The net has a number of different (obviously copied from one another). 1 Tablespoon Butter(or Margarine) 1 Tablespoon of flour 1 cup milk or 1 Tablespoon Butter 1 Tablespoon flour 1/4 cup of milk (this is going to end up as a single great glop) or 3 Tablespoons Butter 3 Tablespoons flour 2 Cups of milk There are a few other and some with what I think are truly bizarre additions. I suspect I come close to the first one, though I never measure anything, and I think i end up using more milk. Variations are I use cream/milk , milk/white wine (usually for seafood and tarragon) I have made it with beef stock but I am not sure it is classed as a "white sauce" What say you is there a magic ratio?
  9. Depends whether you want the individual bits intact or you want to treat it as "protein lump" or "vegetable matter" If you only need blocks go with the hacksaw (get a proper stainless steel food grade one rather than one from the tool shed 😟) If you place the block in the fridge (overnight?) until it temperature rises to just below freezing (but still frozen) you may be able to readily break it apart by dropping it or prying it. It may readily come apart. (you could do the same by putting it in an ice slurry but its doing to take a long time for the temperatures to equalize) The basics for NOT refreezing is that originally the food will have some bacteria (all foods do unless pasteurized and handled in sterile conditions) and these pathogens multiply in rates directly related to temperature. Even at freezer temperatures, there is some increases. Its a numbers game. These pathogens generally multiply at exponential rate so it important what the starting number is. Each refreeze increases the starting number. So keeping the whole lot as cool as possible allows refreezing but note the resultant longevity in the freezer may be markedly reduced. I would NEVER do this with raw chicken or offal products because of the types and numbers of pathogens present in these products. If its squid and the individual squid are laid out evenly then the fridge method is the way to go as long as you don't let it get above freezing Squid are slightly different in that their tissue contains a chemicals that break down with time (even in a freezer but it is slowed markedly in the freezer). This turns the squid pink and makes it fluorescent, if you like it is deteriorating and "rotting". It will taste off and smell unpleasant. It will cause skin irritation. (just ask fisherman who use lots of squid for bait)
  10. Bernie

    Turmeric

    according to the "people what know all about such things..well they say they know....they also sell to the gullible...." (..on the internet so they must be real and ethical of course) Tumeric has at least 12 major benefits and will cure Blood clots Depression Inflammation Skin Health Arthritis Cancers Diabetes Obesity Inflammatory Bowel Disease Cholesterol Pain Toxicity So that is why you never ever see an old sad fat vampire with pimples and a sweet tooth in a oncology ward, holding his stomach and rushing to the loo....see it does work! I am going to apply for funds to prove it cures covid! What a crock of the brown stuff that sticks to blankets.
  11. Wasn't wheat germ a by product of the flour refining process so rather than waste it a clever marketing campaign to ensure you had enough roughage to prevent constipation? Mothers loved it to make sure their children were "regular". It could make up for all the quick and easy (and usually atrocious) ready meals from the supermarket. The "Health Food Movement" ensure its success. Healthy food had to be different (close to unpalatable), but you added all sorts of dried berries and fruit to make it edible.
  12. This is not fully correct. The water initially added to melt and caramelize sugar is used in order to avoid burning. It will evaporate and the sugar will eventually caramelize (thus polymerize). This is not related to the above mentioned increase in boiling point. Pretty sure that is not the whole story. If you were to evaporate all the water then that indeed will be the case. But if you stop the process at say 110C then the volume will be different to what the sugar was alone. if you take cool sugar syrup and heat it it will continue to increase in temperature. Unfortunately, this is not correct. Entropy will ensure this does not happen. Entropy is exactly why it CAN happen. Entropy (in this context) is the measure of the possibilities or any combination of states a chemical or substance can be in. If you like its a measure of the likely hood of the chemical or substance being in any possible random state. In this case it is extremely unlikely, but just because statistically very very small, does not negate the possibility.
  13. cartouche (usually parchment cartouche). Don't you hate it when you know you know what the name is but you can't remember it at the time and then a couple of days later for no apparent reason it suddenly pops in the brain when you are doing nothing related!😕
  14. Doesn't the parchment stop the top of the contents being exposed to the hot air of the oven without a lid or the bit of hot air at the top of the pot if it has a lid on it? That way you don't get any drying of the top layer from exposure to the hotter air rather than the actual cooler cooking liquid. I could be wrong though. ( which is not an unusual occurrence )
  15. Lets back up a bit. Once you mix water with something else (that is dissolve something in it) it is no longer water. It will boil at some other temperature. It may be HIGHER or LOWER. For example if you mix water with glycol (you get anti freeze) but it also increases the boiling point as well. You add sugar to water and heat it and it will form a toffee which will certainly reach much higher than the boiling point of water (and I have had the burns to prove it, so there...) A sauce containing water can certainly get above the boiling point of water but any water NOT Dissolved completely will tend to boil off (that's whats happening in a reduction). In any mixture there will almost never be complete mixing there may still be some undissolved water which will boil at 210F. In physics theory the temperature of the water is the average of all the energy levels of every molecule in the water. In theory there is a possibility that a layer of ice could form on a pot of boiling water if all the low energy molecules were to clump together on the top. The probability is extremely low though.😁 As far as the oven temperature that is more about heat transfer. It will take longer to get the liquid to its boiling point if you set the oven lower. Depending on the oven setting at one particular temperature usually means the oven heats till that temperature, stops heating until the temperature drops (5~20 degrees?) then starts the cycle again. Most thermostats and heaters are pretty crude in a technical sense but they do not really have to be. Personally when doing a long braise I will have the lid on in the oven and initially set to 180C but lower it to 140C after it reaches temperature and remove the lid if I need to reduce the liquid.
  16. OK food scientists out there, here is a question slightly out of left field. When you cook say beef sous vide, at various temperatures there are various reactions ( https://douglasbaldwin.com/sous-vide.html#Safety ....Muscle meat is roughly 75% water, 20% protein and 5% fat and other substances. The protein in meat can be divided into three groups: myofibrillar (50–55%), sarcoplasmic (30–34%) and connective tissue (10–15%). The myofibrillar proteins (mostly myosin and actin) and the connective tissue proteins (mostly collagen) contract when heated, while the sarcoplasmic proteins expand when heated. These changes are usually called denaturation. During heating, the muscle fibers shrink transversely and longitudinally, the sarcoplasmic proteins aggregate and gel, and connective tissues shrink and solubilize. The muscle fibers begin to shrink at 95–105°F (35–40°C) and shrinkage increases almost linearly with temperature up to 175°F (80°C). The aggregation and gelation of sarcoplasmic proteins begins around 105°F (40°C) and finishs around 140°F (60°C). Connective tissues start shrinking around 140°F (60°C) but contract more intensely over 150°F (65°C).) My question is if the temperature is taken above these temperatures but later returned to these temperatures does the reactions still apply. Example: If I was to heat meat to 80c (to cook vegetables or sauce for example) then return the temperature to say 55c, will "....aggregation and gelation of sarcoplasmic proteins..." start to occur (or reoccur)? I do understand any compression or shrinkage (and expelling of water) is probably not reversible.
  17. The reality is that just about MOST diets fail in the long term, unless you stay on it forever. Even then the body will readjust its long term chemical processes to cope with the change. Weight starts to creep up. You are dead right @weinoo Basically you need to eat less or exercise more Fuel in fuel out. Easier said than done for most people. Trouble is by exercising more you will usually increase your appetite. It is just the way the brain works. Habit brain says " more exercise, more volume more snacks more often" Surprising humans cannot re hydrate just drinking water, we obtain ~40% of our water needs from carbohydrates. If you are on a diet low on carbohydrates, the body will convert some of the fats & protein into carbohydrates. (your personal fat reserves (i keep mine round my kidneys and belly ☹️) and your muscles when that runs out) One of the reasons exercise stirs up the appetite. It makes you thirsty (sweat, increase respiration) which causes the brain to require carbohydrates. Most will remember days of heavy exercise or work where you just couldn't drink enough water to quench your thirst. You keep drinking till you need to pee, but you are still thirsty. If you drink beer though you will quench your thirst (well till the alcohol takes over) On this type fasting diet you will eat less per day and your brain readjusts to the appetite occurring at set times. You will retrain your habit brain to increase appetite at set times, not purely in response to exercise. Variations of this type of diet are actually embedded in some religions. Think strict orthodox & sabbath, Lent for the Christians or Ramadan.
  18. Host's note: this post was moved from the Dinner 2021 topic, so the diet discussion can find new life. A better way to diet. Select a time slot to eat. Same time slot every day 6 hour slot works for me but 8 hour slot is easier. During the time slot, eat and drink anything you want, as much as you want. Outside that slot nothing but water! No biscuits, snacks, no sugar in tea or coffee..... For a 6 hour slot you should lose about 5lbs a month, 8 hour slot about 3 lbs a month. Strangely you will find after the initial gouging (you will feel hungry outside the slot) you will moderate your intake. You can drop the slot to 4 hours but that makes it hard on everyone else and you are going to be irritable and obnoxious to everyone around you for the first couple of weeks.. My doctor recommended this method as far more reliable than restricting intake.
  19. Bernie

    White Sauce Question

    Another vote for hot milk (not boiling!) I do the butter flour bit then take it off the heat. Heat the milk in the microwave till hot (no bubbles just hot) Add the milk and stir. It should only thicken a little but it will mix together smoothly without lumps. You don't have to stand by the stove stirring while it thickens. Return to heat to thicken I add a little nutmeg. It fixes up any residual flour taste if I am not cooking with the sauce. I have used half cream but only in a dish where i will be adding strong flavors, it does make the sauce a little bland.
  20. Bernie

    Dinner 2021

    It is bad enough that @Ann_T torments me with her food porn, do you have to do the same? That duck looks so good.
  21. Bernie

    Dinner 2021

    The heads turn dark because of oxygenation which starts as soon as the prawn dies. Freezing or cooling slows the process. Commercially, in the cooking process, you add sodium metabisulphate which is a preservative and stops the oxygenation. If the prawns are snap frozen when caught it stops the process, but the process will start again when thawed. No idea whether you can add preservative to fresh prawns without cooking. The black is the evidence of this process and will show up in the head and digestive track. It makes the prawn unattractive and eventually any bacteria present will spoil the prawn. How long after the heads starts to tun black before the prawn spoils is the same as the question "how long is a piece of string?" Unknowable unless you know exactly how the prawn was treated from the time it was caught. An ammonia like smell usually a prettty good indicator that the prawn is "off" Even prawns sold as fresh may have been snap frozen when caught, but that is NOT a bad thing, it preserves the prawn in pristine condition.
  22. Bernie

    Lunch 2021

    Try a spread of VEGEMITE (or Marmite which is the British poor cousin) on the toast then a single cheese slice then the beans on top. It may not be traditional but it takes it to a new level (and yes I do know I am philistine !!) For those that don't know, Vegemite is made from the "dregs" of beer production. being derived from BEER it must be good! 😁
  23. Bernie

    Beetroot

    yep a hamburger with the "lot" usually includes beetroot (plus bacon, onions, lettuce, cheese, tomato, egg salt & pepper and BBQ sauce and maybe pineapple). Its oversized on a softish sesame seed hamburger bun. The idea is that you would be traveling in a car in your board shots and white teashirt and you were ALWAYS guaranteed to drop the beetroot out as you took a bite and it drops nicely onto your teashirt. Everyone then knows you are a messy eater and will tease you mercilessly. The BBG sauce is bad enough to coat your face and drip on your shirt but the beetroot just adds that little bit more "DOH!!!!!!"😁 But Beetroot does actually add nicely to a salad sandwich. Fresh beetroot slices goes well on its own in a sandwich made with fresh hot toast, but depends on what yours is pickled in. If its strong vinegar then not so nice but if the vinegar is mild it will work.
  24. Bernie

    Eggstatic about eggs

    isn't this topic becoming eggsaggerated ?
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