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A novel brewing process via controlled hydrodynamic cavitation

arxiv.org

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Re: A novel brewing process via controlled hydrodynamic cavitation

#31

Post by toddchambery »

Pitarou wrote: post #24
DavidWanjiru wrote: post #19

Earlier quoted context omitted.

Wait, are we now using Trump's name to make an adjective in the same way we've used Orwell's and Kafka's?

trump (2) verb attempt to convince an audience by repeating an assertion many times

I'll add: "bombastic, unsupported claims"

Re: A novel brewing process via controlled hydrodynamic cavitation

#32

Post by djkrudy »

semi-extrinsic wrote: post #18
1_listerine_pls wrote: post #10

Earlier quoted context omitted.

Do you know whether low pressure boiling can kill bacteria?

I guess mechanically yes, thermally no (if you're below pasteurization temperature). My intuition would be that mechanical bacteria killing is always going to be < 100% efficient, so eventually they will be back in force.

http://www.scientificamerican.com/article/cleaning-water-wit... I think that doesn't apply here, the concept is that CHC purifies the liquid. I'm not sure how much I like that, but I agree that changing the boiling point wouldn't mean that bacteria are irradiated at boil.

Re: A novel brewing process via controlled hydrodynamic cavitation

#33

Post by hyperbovine »

theptip wrote: post #17

Some points that are interesting to me, and warrant further investigation: 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…

Plus just general water savings. Between sparging, boil off and cleanup I've felt pretty bad about brewing in drought-stricken California in the last few years. Also, I'm strictly an amateur brewer, but I thought that the boil had other useful features? (For example, eliminating chlorine.) Do you filter the water ahead of time?

Re: A novel brewing process via controlled hydrodynamic cavitation

#34

Post by djkrudy »

My main concern is, like others below, the opaque beer. I've always known that to be the undesirable effect of "pulverizing" I think of it as maybe twice ground beef can be cooked more evenly than a steak, but the crust and raw elements are what make a steak better. That's an unscientific way to say it, but as a homebrewer I know that efficiency is NOT quality. "Cold brewing" or brewing with CHC may have advantages in releasing/ preserving flavor in hops, but the study doesn't support this claim. I don't care if I get 30% efficiency based on original alphas to extracted alphas if something else is lost. (Like taste, sensory effect or mouth feel) I'm thinking this may be more comparable to "dry hopping", which can be used to give hop forward bitterness instead of the dregs that hops boiled for an hour provide. (Like the difference between the aromatic taste of fresh salsa versus the nearly coppery taste of cooked all day tomato sauce. I love fresh salsa, but you can't replace that "dregs" almost umami flavor brought out in Marinara. Compare Bell's Two Hearted to 3F Zombie Dust. IBU's don't tell the whole story. I'm not discounting these methods, but I don't think that the research is comprehensive enough or takes into account taste enough to talk about completely converting a brewery to these methods.

Re: A novel brewing process via controlled hydrodynamic cavitation

#35

Post by cthalupa »

semi-extrinsic wrote: post #18
1_listerine_pls wrote: post #10

Earlier quoted context omitted.

Do you know whether low pressure boiling can kill bacteria?

I guess mechanically yes, thermally no (if you're below pasteurization temperature). My intuition would be that mechanical bacteria killing is always going to be < 100% efficient, so eventually they will be back in force.

Potentially good enough, though? A proper pitch rate of whatever you actually want in there is going to help with outcompeting any undesirables.

My understanding is that most infections in commercial brewing are usually on the bottling/canning line - Since you've got a smaller volume, the "bad" bacteria or yeast make up a larger total percentage of organisms. Especially if sodium metabisulfite has been used prior to the packaging, since now anything that gets in there is running free by itself.

Re: A novel brewing process via controlled hydrodynamic cavitation

#36

Post by theptip »

hyperbovine wrote: post #33
theptip wrote: post #17

Some points that are interesting to me, and warrant further investigation: 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…

Plus just general water savings. Between sparging, boil off and cleanup I've felt pretty bad about brewing in drought-stricken California in the last few years. Also, I'm strictly an amateur brewer, but I thought that the boil had other useful features? (For example, eliminating chlorine.) Do you filter the water ahead of time?

Where I am the water is very soft, and only lightly chlorinated, so I do not filter. (I do add minerals to improve the mash efficiency and yeast health though). If your water has lots of Chlorine (not Chloramine) then the boil will drive this off, but you might be better off starting with Reverse Osmosis water to get a clean slate, and then adding all the minerals you need.

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.

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