the context already explains that the "pasta" is the "mosto" (must, therefore by a process of deduction, + numerous refs:

1. Wine Machinery | Must Cooler | Primary Equipment | Primary ...
We offer a range of wine equipment, including barrels, bottling equipment, cleaning equipment, filter, garagistes and more.
www.winemachinerygroup.com/index.php?id=4&catId=53 - Cached

Fermented beverage production - Google Books Result
Andrew Geoffrey Howard Lea, John Raymond Piggott, John R. Piggott - 2003 - Technology & Engineering - 423 pages
... into the wine and that different contributions are made by the skins, ... The fresh must may be cooled in a must cooler (either a shell and tube or ...
books.google.co.uk/books?isbn=0306477068...

2. MS150 “Waves to Wine” in Napa, CA | White Mountain Road Club
11 Sep 2006 ... Aside from the beautiful scenery the must cooler temperature was a ... Hill wine regions, en route to the overnight location in Santa Rosa. ...
www.wmrc.org/node/24 - Cached

3. The Australian Wine Industry Technical Conference | About the ...
Anatomy of a young red wine C. Sommers, The Australian Wine Research Institute ... Evaluation of a must cooler for a medium-sized winery J.G. Brown, ...
www.awitc.com.au/past_conferences/Third/ - Cached - Similar

4. The Middelvlei Momberg 2004 is launched — fastmoving.co.za ...
7 Dec 2007 ... a new de-stemmer to help soften the wines and reduce tannins; • a new must cooler to extract fruitier flavours; ...
www.fastmoving.co.za/.../the-middelvlei-momberg-2004-is-lau... - Cached


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Note added at 14 mins (2010-09-14 15:34:10 GMT)
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SORRY, that was meant to be a Confidence Rating of 4





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Note added at 4 hrs (2010-09-14 19:42:29 GMT)
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Actually, I think the must does contain all those things anyway - at least that is how I understand it (I translated the complete wine-making process for a Bordeaux wine school only a few months ago!). In other words, the must consists of more than just the juice, but also the stalks, pips and skins (ie, the bits that contain the tannins).
That doesn't help with the "thermo exchanger" I know, but I'd tend to use something more universally understandable (without being condescending!). But of course this does depend on the register you require. Is it intended for scientists, engineers or academics, or more for the general public?

Will let you know if I find out anything more, but am currently stuck on my own translation - regarding the finer points of canal engineering - supposed to be a tourism document :))

See: Must - Wikipedia, the free encyclopedia
Must (from the Latin vinum mustum, “young wine”) is freshly pressed fruit juice (usually grape juice) that contains the skins, seeds, and stems of the fruit ...

Winemaking - In cookery - For mead production - In Christian liturgy
en.wikipedia.org/wiki/Must

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Note added at 4 hrs (2010-09-14 19:55:46 GMT)
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I think I'd tend to say that the must consists of the juice, stalks, skins and pips.
That at least is accurate, but off-hand I don't know what is meant by "pasta". It definitely didn't feature in my winemaking translation.
Again, I'll let you know if I find anything, but, in the meantime, had better get on with the Meuse canal research! Due in tomorow...

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Note added at 4 hrs (2010-09-14 20:05:45 GMT)
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Actually, I seem to remember that the stalks/stems are removed at the crushing stage - so I think your text has that part right! (sorry about that)

Shouldn't be too long with my translation, as the canal section is only 1 para, then the rest is plain sailing! Cheers!