Hi all-
Seen plenty of posts about using a double bath with an immersion sous vide device to circulate and heat the water.
What about putting the device directly into the milk? I know it's not designed for it, but especially with continuous cleaning, it may work. I don't think it would scald the milk the heating element comes in contact with since it flows through so quickly.
Any thoughts? Anyone try this yet?
Thanks!
..... And what about all the heating after the rennet goes in and curds set?
.....just saying :)
Should have clarified, you're right.
The system I'm proposing is just to heat the milk quickly to required temp for starter. It's a combination of sous vide + induction plate. Once set, would use only induction for the smaller increases needed to cook curd.
Interesting ... My first thoughts are that its a lot of plugs and technology to simply heat milk for amateur cheese makers ... Something a pot of bath water can do.... Keep it simple I say :)
Keep up the good thoughts and ideas ...
Sous vide works wonderfully, but you should not heat the milk directly. Use the immersion heater to heat an external water bath. Then you can use the sous vide from start to finish. I've been doing small batches like this for 2 years. (I actually put a 4 gallon pot of milk in a utility/laundry tub partially filled with water heated sous vide). The perfect way to control temperature during a make.
Thanks. I understand this for small batches, but I am now selling 6lb wheels commercially. I'm trying to find an alternative to heating large volumes of milk (30 gallons) in a small space that can't accommodate a vat or soup kettle.
I would still look at a pot within an external container. Otherwise you have a problem with what to do after coagulation. I have a 240 commercial gallon vat but we also use a 40 gallon stainless stock pot inside of a 70 gallon Rubbermaid cattle watering trough with a 6000w heating element. You can heat quickly with that setup and then maintain with a sous vide heater.I have pictures of my setup posted somewhere on the Forum. That is a lot of volume to heat sous vide. You have to be very careful about heating too slowly. That gives unwanted bacteria a chance to take hold.
Great conversations guys. Ed you are always there to help, thanks
reg
Sailor: in that setup, what do you estimate is the volume of water berween containers and how long does it you to get your 40 gallons to goal temp?
Also sailor: in that setup, how are you draining the whey? Thanks!
That's a loaded question. Depends on the starting temperatures of both the milk and the water in the external vat. Here are some notes from when I was designing that setup. FYI - Based on these calculations, I ended up going with a 6000 watt element to move things along faster. We start with water that is as hot as possible in the vat, not the 100F mentioned in my notes. We also let the milk come up to room temperature around 70F to jump start the process. That is below the threshold where bad bacteria will start to grow. Between 70F and rippening temperature you need to heat quickly and add starter bacteria to outcompete unwanted bacteria. You also need to be VERY careful of lag time/temperature. When your milk is finished heating you will need to quickly drain the external vat or the milk will overheat. Anyway, here are my ramblings. The actual application was implemented differently, but the math is still the same:
________________________________
OK it's been way too long since my college physics days so my thermodynamics is a little rusty.
I am designing my milk "vat". I am planning on using a 70 gallon poly stock tank heated with hot water heating elements as my water bath. I will use a 142 quart stainless stockpot with batches of 30 gallons of milk. I will initially fill the tank up manually with hot water say 100F and the milk will be around 40F.
So, thinking out loud, if I fill the tank up to the 65 gallon level after the milk pot is in place. That would be 30 gallons of displacement for the milk and 35 gallons of actual hot water. So the average fluid (water & milk) temperature would be (35/65)x100 + (30/65)x40 = 72.3F. Let's say 72F. I am trying to decide on the size and number of heating elements. The 110 v 1500W elements are easier to deal with for controllers but may not heat fast enough.
It takes one BTU of energy to raise one pound of water, one degree F. Assuming water & milk are both 8.5 lb/gal So 65 gallons x 8.5 = 553 pounds. It will take 553 BTUs to increase 65 gallons by one degree.
For an electric heating element 1 kw/hr = 3413 BTUs. Obviously, this assumes 100% of the energy goes to heating the water and none of it is lost.
A 1.5kw produces 5119 BTUs/hr. So 5119/553 = 9.25 degree rise per hour
From 72F to 90F = 18 degree rise or about 2 hours to heat to rippening temp. Too long
Two 1500w would give 18.5 degrees per hour. One hour for "make ready", but probably too slow for heating to 125F for thermophilics.
A 4500w would give 27.75 degrees per hour or about 39 minutes to "make ready".
In that setup we drain whey manually.
Sailor - thank you so much. I'm going to look into a similar idea. If you don't mind sharing, where did you purchase the heating element and the poly tank? Thanks again
Is it something like this?
https://www.amazon.com/gp/aw/d/B004NCW2H0?pc_redir=T1 (https://www.amazon.com/gp/aw/d/B004NCW2H0?pc_redir=T1)
Or this?
http://m.plastic-mart.com/category/41/plastic-stock-tanks-water-troughs?mn=pm030z&gclid=CjwKEAjwp-S6BRDj4Z7z2IWUhG8SJAAbqbF3WNPhJj1942u2mHQTkiuit6eldW4DkNCpjnfxRfcSjxoCmm_w_wcB (http://m.plastic-mart.com/category/41/plastic-stock-tanks-water-troughs?mn=pm030z&gclid=CjwKEAjwp-S6BRDj4Z7z2IWUhG8SJAAbqbF3WNPhJj1942u2mHQTkiuit6eldW4DkNCpjnfxRfcSjxoCmm_w_wcB)
Quote from: amiriliano on June 09, 2016, 08:44:30 PMIf you don't mind sharing, where did you purchase the heating element and the poly tank? Thanks again
Poly tank - any farm supply store like Southern States
Heating element - local plumbing supply or lumber store. However 6000w is not common and they may have to order it
Quote from: amiriliano on June 09, 2016, 08:46:56 PMIs it something like this?
https://www.amazon.com/gp/aw/d/B004NCW2H0?pc_redir=T1 (https://www.amazon.com/gp/aw/d/B004NCW2H0?pc_redir=T1)
Very similar. You will need to be able to add a drain to remove water. And you will need to be able to mount the heating element. Some stock tanks come with holes and/or flat surfaces to accommodate plumbing.
Sailor's method is very good--I got to see it first hand a couple of years ago. An option that I use that takes up less space (though it costs a lot more) is using adhesive heating pads, like these: http://www.omega.com/pptst/SRFR_SRFG.html, (http://www.omega.com/pptst/SRFR_SRFG.html,) directly onto the pot holding the milk. My experience has been the 10 watts/in^2 pads do not scald the milk even when left alone (I generally give mine a stir or two while it's heating). The pads themselves have never overheated, and I don't have the volume of milk over again in hot water to deal with. I do 10 gallon batches, 15 a couple of times, and things work well. I use a controller to turn the pads on and off to maintain temp. I manually turn them off once the rennet is added, and turn them back on once the curd is cut. Just another thought to consider if space is more of a premium than initial cost...
Sailor - thank you very much for your help here. Truly appreciated.
Mike, thank you also. Your link doesn't seem to be working. Do you have another?
TY !
Mike - I found it. This is VERY interesting. Do you have a picture of your set up? Specifically I'm wondering what adhesive you used and how everything is hooked up electrically.
Thank you!
I do somewhere...I'll find and post them when I get home.
Thank Mike. It would help me greatly.
The heating pads I bought came with adhesive already attached (looks like they call it PSA pressure sensitive adhesive).
I don't have a single picture that shows the whole setup, so I'll try to tell the story with a few pictures.
Here's the first one:
(https://scontent-ord1-1.xx.fbcdn.net/v/t1.0-9/574995_303187656473348_1923952250_n.jpg?oh=a502886e7e1d3a5d9026b20566ee3bf1&oe=57CD29B3)
You can see that the heating pads are wired together, and connect to a white cord. That white cord is just an extension cord that I cut up for this.
(https://scontent-ord1-1.xx.fbcdn.net/v/t1.0-9/1174826_384544438337669_1661995325_n.jpg?oh=f91b225ff3ad86969b6dbd62f5f8790b&oe=580C8C03)
Now you can see that the white cord comes from the pads and one wire connects to a relay. The other wire reconnects to the extension cord that plugs into the wall. Had I thought through what I was doing better, I would have only cut one of the wires on the extension cord and put the relay between the two sides of that cut wire. Does that make sense?
One the other side of the relay, a set of wires are connected to a PID controller (it looks like I'm sterilizing stuff in this picture since my temp is set to 180 F). Those wires turn the relay on and off. Another set of wires leaves the controller and connects to the extension cord--those just power the controller. Another brown wire leaves the controller--that's the thermocouple that goes in the milk. I got that from omega, too.
Here's another view:
(https://scontent-ord1-1.xx.fbcdn.net/v/t1.0-9/542855_305556666236447_87909298_n.jpg?oh=7e1f99d1fea091150ebc2b12a186df9b&oe=580A7EAD)
Is that clear?
Extremely helpful. Thank you. Now I have to figure out how much surface area I need to cover to increase milk and curd temp at a reasonable rate.