Register Now!

Wine Making & Grape Growing Forum > Wine Making > Tutorials, Calculators, Wine Logs & Yeast Charts > How To Punch Down Your Cap.

Help Support Winemaking Talk by donating using the link above or becoming a Supporting Member.
Thread Tools Search this Thread
Old 11-16-2010, 03:56 PM   #1
Senior Member
djrockinsteve's Avatar
Jan 2010
Posts: 4,908
Liked 117 Times on 92 Posts
Likes Given: 2

Carbon dioxide gas (bubbles) is given off by the yeast during an active fermentation The CO2 bubbles rise and stick to the skins of the fruit you are fermenting. The bubbles make the fruit lighter and they begin to float to the top of your must. This group of fruit is called your “cap”. As the layer of fruit rises, liquid slowly drains away causing the cap to becomes dry, and left this way is an open invitation for bacteria to begin to oxidize your fruit.

Vinegar bacteria convert alcohol into acetic acid, and the acetic acid will spoil your wine. If your cap becomes dry, in a short amount of time vinegar bacteria will set in, grow and convert the alcohol into vinegar. This is called “acetification”. By breaking up and punching down your fermentation cap at least twice a day you will heed off bacteria, and keep your fruit moist and allow for more color and flavor to be extracted from the fruit.

Placing your fruit into a straining bag or cheese cloth will make punching down the cap and the extraction easier. Once the specific gravity reaches 1.020 to 1.015 it is recommended that the fruit be removed from the must. Punching down your cap more than twice a day will not harm your wine.

It is also important to mention that the removal of CO2 gas will help your yeast in the fermentation process and you will have that much less to degas later on. Excess build up of CO2 will stress your yeasts and in some cases stall a fermentation. By punching down your cap you will also be introducing much needed oxygen the yeasts need to survive.

Photo A. Chunks of pineapple lifted to the top of the primary by CO2 gas.

Photo B. As the “cap” is broken CO2 gas begins to be separated from the fruit.

Photo C. Fruit begins to sink back into the must as CO2 gas is released.

You may use a sanitized spoon to punch down small caps. Larger primaries may need specialized equipment.
People say how fast time flies when you are engaged. Just wait till your married. See how fast it flies then.

Reply With Quote
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Similar Threads
Thread Thread Starter Wine Making Forum Replies Last Post
Fruit Punch Wine (help!) ReoZataku Beginners Wine Making Forum 3 10-03-2011 01:05 PM
Hawaiian Punch Psuedowine mrfunk Special Interest Wines 6 03-15-2011 10:21 PM
Cap Punch Down Tool vscottcolorado Wine Making from Grapes 9 09-25-2010 04:59 PM
Tropical Goose Punch seth8530 Special Interest Wines 49 06-24-2010 10:37 AM
Strawberry Wine Punch Tom Recipes 3 04-25-2010 09:47 AM

Forum Jump