Adventures in Vacuum Concentration

[lordratner]

For those of you (like myself) without a copy of Modernist Cuisine, the Vacuum Concentration rig can be seen on this page. 

 

I have successfully eBay-ed myself into a functioning vacuum concentration setup. Hopefully this thread will not only serve as a chronicle of the various successes and failures I have with the technique, but as a place where others can do the same. If I end up being the only one (dumb enough) to play around with this setup, at least everyone can pitch ideas for what to concentrate next. 

 

I know there are a few people here who played around with rotovaps. I don't have the ability to capture solutes, but this idea for this thread is more to discuss the actual products of vacuum concentration, rather than the strengths or weaknesses of the technique (I think that would go in the Kitchen Consumer forum anyhow).

 

First attempt: Concentrated Clarified Orange Juice

 

This idea stemmed from Dave Arnold's agar clarification technique, which I was moderately successful with. The end product had a very mellowed-out orange flavor, and I thought vacuum concentration would be perfect for getting that kick back in it. 

 

This attempt was rushed, so I don't have as much data to provide, but the next project (Jack Daniels) was done in a more controlled, recorded manner.

 

500g of Clarified OJ for ~75 minutes yielded ~160g of clear amber syrup. 

 

Vacuum Concentration in action - https://www.filepicker.io/api/file/ZJLGs3YJQbpAV0aV5MAb (sorry for the huge pic, I'll resize future images)

 

End product - https://www.filepicker.io/api/file/mtDDhDrQD21ZYFQrmtek

 

The sauce was very orangey, with a fair bit of bitterness (though not unpleasant) from the citrus. I'm going to try adding it to sparkling wine for a less-diluted mimosa. I don't have many orange recipes, so it'll probably spoil before I use it for something else.

 

I'm reducing a bottle of Jack Daniels right now. I'll post results tomorrow.

[Anna N]

We need a way to stop Kerry Beal from reading this! She is about to freeze-dry everything that remotely resembles food and if she sees this.......Oy vey!

[Martin Fisher]

Very cool.

I have the aspirator and flask...still looking for a good magnetic stirring hot plate.

[Kerry Beal]

Very cool.

I have the aspirator and flask...still looking for a good magnetic stirring hot plate.

I know there is one of those in the lab downstairs that they don't use anymore!  And I've got flasks - lots of flasks.   What kind of an aspirator do I need?

Edited September 8, 2014 by Kerry Beal (log)

[Martin Fisher]

A faucet aspirator will work but a circulating aspirator is better.

I've converted a faucet aspirator to a circulating aspirator via a pump.

 

FWIW, it is possible to do vacuum reduction without a magnetic stirrer/hot plate if anyone happens to want to try this on the cheap.

[Smithy]

Very, very cool!

You indicate that the orange concentrate may go off before you can use it all. Can you freeze it? Are you considering it only for drinks? It should be a good cooking ingredient also: duck a l'orange, citrus-roasted chicken, drizzled over fruit salad like cointreau. If you're interested in ideas for use of your concentrates, let us know. It may be worth its own topic. :-)

Thanks for posting the link to the Modernist Cuisine blog so some of the rest of us can try this too.

[lordratner]

Very, very cool!

You indicate that the orange concentrate may go off before you can use it all. Can you freeze it? Are you considering it only for drinks? It should be a good cooking ingredient also: duck a l'orange, citrus-roasted chicken, drizzled over fruit salad like cointreau. If you're interested in ideas for use of your concentrates, let us know. It may be worth its own topic. :-)

Thanks for posting the link to the Modernist Cuisine blog so some of the rest of us can try this too.

Ideas for recipes specifically using these concentrates are welcome, in fact, I'm hoping the ideas here can justify the unit itself.

 

I've since thrown the orange sauce into the freezer. I like the duck idea, and I'm planning on fooling around with duck meat for burgers this weekend, so a side project of duck l'orange may be the ticket.

[lordratner]

Very cool.

I have the aspirator and flask...still looking for a good magnetic stirring hot plate.

The Nuovo II used in my setup is probably the most common stirrer hot plate on ebay. I waited to find one that looked clean and functional. Mine had a very badly frayed cord, pushing the price down to $87 IIRC. I replaced it with a computer power cord (took about 10 minutes) and it's good to go. 

 

It doesn't get terribly hot (300C max) but that's more than enough for my needs. I figure if I use it long enough and really find value in the setup, I can buy a digital stirring hot plate and newer aspirator pump with pressure gauges. 

[Shalmanese]

I've always been interested in the idea of making sorbets purely via the natural sugars in the fruit instead of adding sugar. Have you considered sorbet making?

[lordratner]

I've always been interested in the idea of making sorbets purely via the natural sugars in the fruit instead of adding sugar. Have you considered sorbet making?

I have, however that's really only likely to happen if I can figure out a reliable way to get liquid nitrogen in the UK for less than a billion pounds. We're only here for a few years, so buying a ton of UK appliances isn't something we're willing to do, and an ice cream maker is a bridge too far. 

 

I like the idea. The concentrate is quite sweet, considering the initial clarification took out a lot of the sugars. I should know the LN2 feasibility in a few days.

[Smithy]

I've always been interested in the idea of making sorbets purely via the natural sugars in the fruit instead of adding sugar. Have you considered sorbet making?

Watermelon sorbet would be a good start. I've done that just by pureeing watermelon flesh and churning it in an ice cream maker, with reasonable success. Getting the pure essence sounds like just the ticket. Then again, there's peach sorbet, or mango, or pineapple...wow, the sorbet idea sounds great!

[Shalmanese]

I have, however that's really only likely to happen if I can figure out a reliable way to get liquid nitrogen in the UK for less than a billion pounds. We're only here for a few years, so buying a ton of UK appliances isn't something we're willing to do, and an ice cream maker is a bridge too far. 

 

I like the idea. The concentrate is quite sweet, considering the initial clarification took out a lot of the sugars. I should know the LN2 feasibility in a few days.

I've always just frozen it solid, then used a blender to puree. The quality is pretty good with a high powered blender. With a granita, you don't need any tools more sophisticated than a fork.

[lordratner]

I've always just frozen it solid, then used a blender to puree. The quality is pretty good with a high powered blender. With a granita, you don't need any tools more sophisticated than a fork.

If you can point me to a recipe or set of directions, I'll whip something up with the orange concentrate either tomorrow or this weekend.

 

Thanks! This is exactly the type of info I wanted for this thread... and hopefully some other people trying the technique out.

[Smithy]

Shalmanese beat me to the granita comment. :-) I'll note that semifreddo also doesn't require an ice cream maker. It does, however, include sugar. In case you're interested, here's a link to the Fine Cooking article that put me on this path: http://www.finecooking.com/videos/how-to-make-semifreddo.aspx

[Shalmanese]

If you can point me to a recipe or set of directions, I'll whip something up with the orange concentrate either tomorrow or this weekend.

 

Thanks! This is exactly the type of info I wanted for this thread... and hopefully some other people trying the technique out.

There's not really a recipe, you want to get a liquid up to about 30 brix (30% dissolved solids) with the majority of it being sugar. Some alcohol can also be used in place of sugar to control texture and a small amount of invert sugars (corn syrup) can help with the texture. Simply freeze, put in a blender and blend until it forms a slushy texture and then freeze again.

The easiest way to check (if you don't have a baume meter) if you're at the right sugar concentration is to just freeze and check the texture. If you make a mistake, thaw, adjust and freeze again. If it's dry and powdery, let it thaw and add more dissolved solids. If it's soft and slushy and weeping, add more water/fruit juice.

Edited September 9, 2014 by Shalmanese (log)

[lordratner]

Second Attempt: Jack Daniels Whiskey

The set up on this one was easy. Dump a bottle of Jack into the flask and go.

When starting a liquid in this rig, an initial boil-over period has to be watched carefully. If left on its own, the liquid will bubble up to the hose port and liquid will get sucked out. Not a threat to an aspirator pump, but a waste of good ingredient. Relieving the vacuum momentarily crushes the bubbles. and after a few vents, the system reaches some sort of equilibrium. Each time the system is stopped, this process has to be repeated. Because of this, I won't be taking periodic weight measurements after this attempt, but relying on liquid height in the flask.

Choosing the speed of the spinner has a larger effect on the over-boil effect than temp. It gets trickier as the liquid gets thicker.

The Jack turned a rather ugly brown towards the end and made huge, but mostly manageable bubbles

And the end result:

Honestly I consider it a failure. Apparently whiskey is made of smoke and alcohol. Any "flavor" was lost in the solvent; you could smell it in the aspirator tank. This is where a rotovap would shine. I'm not sure if I'll do anything with the end product. It tastes like the inside of a burnt barrel, which is fitting considering how Jack is made. I may try to add some sort of smokey flavor to a sauce or gravy with it.

Next up, Red Wine and Vinegar for the Red Onion Jam from ChefSteps

Edited September 29, 2014 by Smithy
Forum technical question removed, with member permission (log)

[Smithy]

 

When starting a liquid in this rig, an initial boil-over period has to be watched carefully. If left on its own, the liquid will bubble up to the hose port and liquid will get sucked out. Not a threat to an aspirator pump, but a waste of good ingredient. Relieving the vacuum momentarily crushes the bubbles. and after a few vents, the system reaches some sort of equilibrium. Each time the system is stopped, this process has to be repeated. Because of this, I won't be taking periodic weight measurements after this attempt, but relying on liquid height in the flask.

I don't see a vent in your setup. Are you easing the stopper, or am I overlooking the vent somewhere?

[Kerry Beal]

Not sure I would vent a vacuum system.

[lordratner]

I don't see a vent in your setup. Are you easing the stopper, or am I overlooking the vent somewhere?

 

For now I just ease the hose off the flask port. If the pump turns off before the hose is disconnected, the flask sucks in water (lots of it) from the aspirator tank, ruining the product. I'm going to install an intermediate flask with a more permanent venting system that will also act as a water catch in case of pump failure.

Not sure I would vent a vacuum system.

Not a permanently open vent, but one that allows for bubble control. If I stick with the system long enough, I'll buy a vacuum control valve so I can control the temp of the liquid as it boils.

[KennethT]

Can you put a check valve in your hose? That should stop the back flow from getting into your flask.

[lordratner]

Can you put a check valve in your hose? That should stop the back flow from getting into your flask.

Yes, but until I come up with a permanent place in the home for this (and a few other not-so-kitchen-decor setups), I don't want to have a bunch of things hanging off the hose.

[lordratner]

Red Wine and Vinegar Reduction

 

I decided to make the ChefSteps Red Onion Jam, which calls for 1000g of wine and 50g of vinegar to be reduced down to ~105g

 

 

This time I kept the rig running without any pauses to measure the weight. Benefit: no uncontrollable foaming like with the Jack Daniels. Downside: over-reduced down to about 70g. But it still worked well in the jam.

 

 

Instead I used a dry erase pen to mark the starting level. Not an elegant system, but it at least provides a reference. The entire process took about 2 hours to reduce

 

 

The jam was really good. Very oniony still (which store-bought versions seem to lack IMO), but with a great sweet flavor. A great addition to our burgers

 

 

What I do not know is whether the product would have tasted any different being reduced on the stove, as the orange juice did. More experiments to come.

[rotuts]

lordratner

 

how long did that wine reduction take ?  what was the temp of the reduction as it was reducing ?

 

many thanks for sharing .

[lordratner]

lordratner

how long did that wine reduction take ? what was the temp of the reduction as it was reducing ?

many thanks for sharing .

2 hours. It started at about 75F when the pump water was sub 50F, and rose to about 100F when the water was at room temp.

[Smithy]

Is there a scale upon which you could put the stirrer and the flask, so you could measure reduction on the fly? I don't know how much your apparatus already weighs, nor how much it vibrates.

That onion jam looks and sounds delicious.