Winegrowers Supplies - Internal Plates, Snakes or Coils, for cooling or heating
The temperature of a fermentation has a significant effect on the quality of a wine. Wine yeasts create different compounds at different
temperatures. Cooler temperature fermentations preserve more aromatic esters and create lean, focused wines, but often with reduced
'mouth feel'. Warmer fermentations give greater complexity and mouth feel, but at the loss of the original clarity of the grapes.
The warmer a fermentation gets, a higher amount of H2S will be produced. The ideal is to be able to control the fermentation temperature within a desired range, for the style of wine we are trying to make, while not allowing it to get too hot.
Snakes: a very popular alternative to plates, the great advantage being that the tank lid doesn't have to be modified, you just feed the snake through a hole (at least 35 mm diameter) in the lid so that it hangs vertically down. They can also be used with fixed capacity tanks or wood barrels.
They can be used for cooling or heating. If used for heating a longer snake can be used, which coils around on the bottom of the tank, with the heat rising upwards.
0.6 metres long, 0.11 square metres, £138
Choosing the appropriate size depends on the temperatures you want to reach and on the temperature of the liquid.
For 500 litres I suggest using 2.5 metres and for 1000 litres I would use 3.5 metres.
The flexible/corrugated tube-within-a-tube is made from AISI 316 stainless steel.
Water or 30% glycol solution is pumped into the outer tube and flows back out through the inner.
The inlet is at 90 degrees and the outlet is straight. It's very important that these are connected correctly.
The inlet has ½" female bsp thread (except for the 8.0 metre snake which has ½" male bsp thread) and the outlet has ½" male bsp thread.
I can supply adaptors from ½" to ¾" bsp in order to use ¾" bsp female hose-tails for 20 mm id tubing:
white polypropylene or stainless steel adaptor ½" female to ¾" male, £4.90,
white polypropylene adaptor ½" male to ¾" male, £1.90.
A special 2" black plastic fitting is available to go in the tank lid, in
addition to the normal air-lock fitting, so that the snake can be used during fermentation, £9. A hole needs to be cut in the lid.
A special silicone-rubber bung with a large hole to push the snake through, and then hold it in place, £19.
Italian plates: 370 mm wide x
1+1 mm AISI 304 or on request AISI 316.
The length of tube above the top of the plate is 175 mm until the thread starts.
The plates are double welded at the seam and at the edge: there are no gaps where the two SS sheets are welded together. This makes them more secure, and there are no rough joints or sharp edges. They are electrolytically polished after completion of welding operations, resulting in an extremely smooth surface (easy to clean). They are pressure tested at 8 bar - operating pressure is up to 5 bar.
The plates are normally installed into lids of variable capacity tanks. For each plate, two holes 21 mm diameter need to be drilled in the
lid, at 290 mm c-c. No welding is needed.
Special seals (photo above) for where the plate goes through the lid @ £6 per set of two; a stainless steel nut (½" bsp internal thread) with s/s washer and a silicone seal; photo above.
A stainless steel ½" bsp bolt can be used in place of the above fitting, to seal the hole after the cooling plate is removed.
Inlet/outlet pipes have long ½" male threads, with adaptors this can be increased to ¾" after installation:-
¾" hexagon male-thread with ½" inner female thread @ £6 each; two needed per plate.
The additional weight of a plate is such that a small winch may be necessary to lower and raise the tank lid; hand-operated winches are available from many sources, e.g. the TW1200 from http://www.machinemart.co.uk/shop/categories/search/hand-electric-winches.
Two plates can be fitted to one tank lid, for greater cooling. With 2 plates it is worth fitting a strengthening/bracing sheet to increase the rigidity of the lid.
The cooling liquid can be cold water. For a much more
efficient method then a closed circuit system using a glycol (antifreeze)
solution recycled through a heat exchanger, enables the water-mixture to be
cooled to a much lower temperature. A low speed pump is needed for circulation,
with controllable flow rate to enable the temperature of the fermenting juice to be adjusted.
The ideal is, once the fermentation has started, to reduce the juice temperature to just below 10 °C, which should enable the fermentation to last 3 to 4 weeks.
Tartrate crystals precipitate on the plates but these would precipitate anyway, during the winter, on the tank walls.
Heat Exchanger coils:
Stainless steel (AISI 304, V2A) tubular spiral, ¾":-
0.6 square metres, 270 mm diameter, 600 mm high, £280
Cooling/heating temperature controller:- £195
Prices shown are exclusive of Vat.
Delivery usually will need to be charged at cost.