a Tale of two Cab (kits)

[vizsla_red]

kit 1 : RJS Cru international Cab with dried raisin-like things
temp a perfect 72-74 with thermostat temp controller
march 6th start SG 1.094, sealed tight in big bubbler - bubbling away
march 8th SG 1.072 first stir, twice this day
march 10th SG 1.070 cheated and added maybe 2 oz yeast nutrient from kit #2
march 11th Day 5 SG 1.050

kit 2 : Master Vintner, cab with skins
temp a perfect 72-74 with thermostat temp controller
march 6th start SG 1.094, 7.5 gallon bucket, lid sitting top, NO bubbles in airlock
march 8th SG 1.080 lots of little bubbles when I stir, two stirs today
march 10th SG 1.040 added all but 2 oz of yeast nutrient
march 11th day 5 - SG 1.020

first kit started out faster but has slowed,
2nd kit now going faster ? wider mouth bucket letting in more oxygen with stirring?

should I make it a point to stir kit 1 even more frequently?
should I add some more yeast nutrient, even though it is not directed to do so in the kit instructions?

 

[jsbeckton]

Same yeast? I have made about 15 premium kits without and yeast nutrient and while the fermentation times varied a bit they all finished just fine.

Is the 72-74 the must temp or chamber temp? Might find that the must temp it much higher although I wouldn’t worry about it too much.

 

[vizsla_red]

wish I'd have paid more attention,
they were both lavlin yeasts, but I didn't make note of the strain number/style.

those are MUST temps, taken via 12" probe

 

[jsbeckton]

The vigor can vary quite a bit with different strains. I wouldn’t worry about the temp too much as long as it stays below 80-85 at peak. In fact it might not hurt to let it go up a bit more after the fermentation starts to wind down so you get a strong finish.

 

[vizsla_red]

1st cab is now in secondary
Have a little over a half gallon left
Should I keep topping up carboy to within an inch of bung?

How can I keep the remainder, under an airlock? For such a small 1-2 bottle volume

 

[vizsla_red]

From the pics above, I topped off maybe 2 oz more, getting it closer to the bung, which wound up being too much — and wine was coming into air lock,
so I siphoned OFF 1-2oz,
Now that the bubbling has RE-subsided, it is here:

i apparently needed a 6.5 gallon carboy


So I took the extra half gallon, put it in a 1 gallon cider jug, after sanitizing it, I charged the jug with a few sprays of co2 from a small catkrteidge, and a hand held trigger thing, to displace as much o2 laden air as possible

The half gallon was the last bit out of the primary, and seems to have had some lees / sediment come with it.

It looks like this:


Should I be worried about the stuff floating on top?
Or that has sunk to bottom?

Should I wine-thieve some off from the middle of this half gallon to fill up big carboy a bit more?

Is this half gallon trash? (Based on the floatsum and stuff in bottom)

 

[tradowsk]

With the last half gallon that has a bunch of lees, put it in the fridge for a day or 2 to cold crash it and get all the lees to settle quickly. Then pour off the clean wine into another sanitized jar and use that to top up the main carboy. I use this method at the first 2-3 rackings to minimize loss

 

[vizsla_red]

. . . put it in the fridge for a day or 2 to cold crash it and get all the lees to settle quickly. . .

Can you explain cold crashing?

Reason
Mechanism
How do you know how long to do it?
Is there ever a situation where you should absolutely not do something like this?

 

[tradowsk]

Can you explain cold crashing?

Reason
Mechanism
How do you know how long to do it?
Is there ever a situation where you should absolutely not do something like this?

Cold crashing is putting your wine into a cold environment (usually the fridge since it's a stable temperature) for a short period of time to speed the settling of gross lees and other larger particles out of suspension. The cooler temperature makes the yeast go dormant and draws them out of suspension to settle on the bottom more quickly than leaving it at room temperature.

So your half-gallon of murky wine still has quite a bit of good wine left in it that you should try to salvage, and popping it in the fridge for a day or 2 will separate the solids. You can then pour off the clearer wine on top to add to your main batch and not waste it. You'll be surprised how much wine you can recover on the first couple rackings where there is a lot of lees. The actual time to leave it in the fridge depends on the wine itself, it will be obviously separated when it is ready but I don't think I've ever had to go longer than 2 days.

Now, there is also "cold stabilization" where you leave the entire batch in the fridge for a couple weeks to get acid crystals to drop out in the carboy instead of in your bottles. I don't usually do this because it can alter the pH of the wine. Also, most kit wines are pre-balanced to minimize excess acid that could precipitate out after bottling.