The main difference between this setup and a RIMS is that they don't mill the malt when they allow the grain to be circulated. The cavitation pulverises the malt. This is actually a massive benefit because dry milling malt is a major cause of infection in a brewery.
The other benefit is that they are able to mash at a much lower temperature and still get decent extraction. Even down to 48C (118F) allows them to get 91% efficiency in one case. This is on par with RIMS (most reports I've heard is that people can manage mid 90s efficiency), but of course rims has to maintain a temperature of about 65C (150F).
Side note: Their reported temperatures for mashing without recirculating the grains is a bit crazy -- in the mid 70's C -- all much over 160F. They are going to be deactivating enzymes at those temps and that probably accounts for their decreased efficiency. I really can't understand what they were thinking.
There is some mention of protein make up, but my main worry about mashing at such a low temperature is the break down of larger proteins. They have a picture of frothy beer with a caption about foam stability, but the proof of the pudding is in the eating. Also, that picture shows a very hazy beer.
The other thing they talk about is isomerising the hops without boiling. That's pretty cool and would definitely reduce power usage. But again... that picture of nearly opaque beer haunts me.
Finally they talk about cavitating the fermenting beer in order to remove CO2. That seems reasonable, but I would worry somewhat about how the yeast drops in that condition.
To be honest, I wish they had stuck to mashing in this paper. It's strange to see a paper cram as much as this one does in one place. Normally you want to stretch it out over as many publications as possible ;-)
The last thing I'm curious about is how they produce the cavitation. I really couldn't understand their description at all. Is it just a matter of the design of chamber in which they pump the wort? That would be extremely cool, but I'd like to see a better description. A mash system that depends only on pumps would be ridiculously nice to have.
From the OP paper: "A Venturi tube, with the same geometry used in a previous study (Albanese et al., 2015), is used as the cavitation reactor and preferred over an orifice plate since it was observed that orifices are quickly obstructed by the circulating solid particles. "
The referenced paper gives specifications for the Venturi tube:
"The cavitation reactors used for the experiments were an orifice plate equipped with 156 holes (each having an internal diameter 2 mm) and a Venturi tube (Fig. 2A and B). Both are upscale models of effective configurations used in laboratory scale experiments by researchers in India [23, 28]. The orifice plate total opening was 490 mm2 (6.55% of the main pipe’s inner section). The corresponding value for the opening of the Venturi tube’s nozzle was 452 mm2 (6.05% of the pipe’s section)."
Might not be too difficult to obtain such a device.
1: http://onlinelibrary.wiley.com/store/10.1002/ese3.62/asset/e...
Don't mill in the same area you're brewing and this is pretty much handled. Lacto carries with dust, but just don't do anything post boil in that area and you're fine.
>This is on par with RIMS (most reports I've heard is that people can manage mid 90s efficiency), but of course rims has to maintain a temperature of about 65C (150F).
I sit in low 90s with a rather low tech HERMS setup.
>but my main worry about mashing at such a low temperature is the break down of larger proteins. They have a picture of frothy beer with a caption about foam stability, but the proof of the pudding is in the eating. Also, that picture shows a very hazy beer.
I'm curious about the lower temp mashes and getting enough longer chain sugars for those of us that spend a lot of time working with brett.
As for the haze... Maybe the like NEIPA? ;)
The mechanism they use in the video has no moving parts! It's just a matter of forcing water through opposing nozzles.
Somehow, though, that's the only mention of the flavor profile of the beer produced. They do describe measuring some key properties with a BeerLab, but those numbers hardly tell a complete story.
Given the horrid state the mash ends up in, and the fact that it isn't removed until the water has reached 78C, I'd expect plenty of tannins to be swept along in the race to efficiency.
I'd also briefly like to complain about the sad charts in this paper. What order are those bars in? Where are they drawing the conclusions in the text from? Why are the data points collected so inconsistent?
attempt to convince an audience by repeating an assertion many times
For all his faults, I thought he came across pretty good tonight.
I've never liked the man on a lot of levels, but tonight he did better than I anticipated. He has been doing some homework.
1) Milling of malts is no longer required. As a microbrewery operator, now I don't need to come in the day before to run the mill for a planned brew. Massive win on scheduling and convenience.
2) "Concerning mashing and sparging, the new equipment allows to eliminate sparging altogether since the pulverization of cavitating malts ... prevents practically any starch to remain trapped into the grains". Again, from a microbrewery operator's perspective, another few hours of labour saved per brew, since I don't have to run a few sparges over my grain.
3) Since cavitation apparently sanitizes the wort, we don't need to do a boil. This saves another 1.5 hours on a brew, removes the need for a boil vessel, and some other equipment in my brewery (steam boiler to heat the boil vessel, a bunch of plumbing for said steam).
4) related to 3, the hops can be isomerized without boiling. I've had great success with low-boil techniques like the hop stand, so I'd assume that CHC beer would capture a lot more of the volatile aromatics from hops. This could lead to some great IPAs.
I'd love to figure out what the MVP is for this rig, and whether it could be replicated at homebrew scale, as it seems to simplify the process massively.
Another important reason for the boil is driving off DMS (which causes a cooked corn off-flavour).
The paper covers both of these, I think:
"Due to the strong liquid degassing properties as a result of hydrodynamic cavitation processes (Clark, Dewhurst, Payne, & Ellwood, 2001; Gogate & Pandit, 2011; Iben, Wolf, Freudigmann, Fröhlich, & Heller, 2015; Senthil Kumar, Siva Kumar, & Pandit, 2000), undesired volatile aromatic compounds are safely expelled after few minutes of cavitation"
Sounds like this would apply to the volatile chlorine as well, but I'm not certain about that.
Also sounds like this should be more rigorously tested, as I don't see anything by way of data to back up this claim; perhaps the cited papers explain more.
That said, I found their off hand mention of using it as an alternate to high temperature pasteurization as much more intriguing. Mostly because I detest the "cooked" taste of ultra-pasteurized cream but have been finding it harder and harder to find cream that hasn't been over pasteurized in this way. Find me some cream that is "cold pasteurized" and tastes like cream, I'll be really happy.
https://www.technologyreview.com/s/602464/this-technology-is...
Yeah, they don't know shit about beer.
