The Straight Dope

Go Back   Straight Dope Message Board > Main > General Questions

Reply
 
Thread Tools Display Modes
  #1  
Old 06-16-2010, 03:53 PM
Jamaika a jamaikaiaké Jamaika a jamaikaiaké is offline
Guest
 
Join Date: Jan 2006
Avocados. Why ripen in a paper bag? Why not any bag?

Moseying around these, our intertubes, I've found much advice about how to ripen an avocado: in a brown paper bag.

In a bag? This I get.

In a brown paper bag? Why would this matter? Does it?
Reply With Quote
Advertisements  
  #2  
Old 06-16-2010, 04:01 PM
redtail23 redtail23 is offline
Charter Member
 
Join Date: Mar 2000
Posts: 2,926
Storing them in a paper bag allows some of the ?ethylene? gas to escape and allows regular air in. They'll ripen faster because of the increased concentration of ethylene.

Storing them in a plastic bag doesn't allow the gas exchange and they tend to rot rather than ripen.

I just learned about this the other day (Alton Brown, maybe?), but it's true in my experience. I just didn't know why.

Last edited by redtail23; 06-16-2010 at 04:02 PM.. Reason: cuz i'm an idjit sometimes
Reply With Quote
  #3  
Old 06-16-2010, 04:27 PM
Zsofia Zsofia is offline
Guest
 
Join Date: Feb 2001
Also a plastic bag keeps moisture in, which makes many things very nasty.
Reply With Quote
  #4  
Old 06-16-2010, 09:39 PM
Blake Blake is offline
Member
 
Join Date: Mar 2001
Posts: 10,207
Quote:
Originally Posted by redtail23 View Post
Storing them in a paper bag allows some of the ?ethylene? gas to escape and allows regular air in. They'll ripen faster because of the increased concentration of ethylene.
So some of the gas escapes, and that causes an increased concentration of the gas?

Look, the fact is that most plastic bags are polyethylene. Poly-ethylene. It's inherently unstable. The stuff breaks down naturally. All the time. Constantly releasing ethylene.

Ethylene is a plant hormone. It plays a major role in ripening of most fruits. If the concentration gets too high the fruit ripens in odd ways. In avocados that means that the layers of flesh next to the skin ripen well before the inner layer, and then starts to decompose. So you end up with a fruit that is mushy and brown on the outside and hard as a rock on the inside. Not very appetising.

By using a paper bag you are not exposing the fruit to ethylene from the plastic bag. Fruit naturally produces ethylene too, and the paper also allows this to escape, preventing a buildup.

Why brown paper bags? Because most white paper bags are treated to make them smoother and, incidentally, more gas tight. That's why mots white paper bags are shiny. That treatment ranges from applying a layer of starch to actual plastic coating. Of the bags that commonly available, only the brown paper type have the coarse surface fibres that are needed for free gas exchange. So rather than confusing people with the technical details of which bags to use, the advice is simply to use brown paper bags.
Reply With Quote
  #5  
Old 06-16-2010, 10:08 PM
TheChileanBlob TheChileanBlob is online now
Guest
 
Join Date: Dec 2008
But the paper bag allows some buildup of ethylene, so they ripen faster than if they were sitting in a bowl on the counter.

If you have more than one avocado, they share their gas with each other and it helps them to ripen. If you just have one, you can put an apple or a banana in with it to help it along.
Reply With Quote
  #6  
Old 06-16-2010, 10:48 PM
Fuzzy Dunlop Fuzzy Dunlop is offline
Guest
 
Join Date: Apr 2007
Quote:
Originally Posted by Blake View Post
Look, the fact is that most plastic bags are polyethylene. Poly-ethylene. It's inherently unstable. The stuff breaks down naturally. All the time. Constantly releasing ethylene.
Do you have a cite that polyethylene is inherently unstable, breaks down naturally without the presence of heat or UV light or that an otherwise empty polyethylene bag will fill with ethylene gas?
Reply With Quote
  #7  
Old 06-17-2010, 12:10 AM
DSeid DSeid is offline
Guest
 
Join Date: Sep 2001
Polyethylene breaks down very slowly. The problem with a polyethylene bag is indeed that it is airtight. Increasing the local concentration of fruit produced ethylene is one thing, and indeed causes artificial ripening, but enough CO2 has to get in and O2 out. A microperforated polyethylene bag works great. Both that and brown paper bags keep enough ethylene in to ripen while being permeable enough to keep the CO2/O2 balance at acceptable levels.
Reply With Quote
  #8  
Old 06-17-2010, 04:49 PM
robcaro robcaro is offline
Guest
 
Join Date: Nov 2001
Sometimes I just roll up the fruit in a page of the newspaper. Works for me, but I don't know if the paper bag is better or not.
Reply With Quote
  #9  
Old 06-18-2010, 01:30 AM
Indian Indian is offline
Guest
 
Join Date: Sep 2007
Quote:
Originally Posted by DSeid View Post
Both that and brown paper bags keep enough ethylene in to ripen while being permeable enough to keep the CO2/O2 balance at acceptable levels.


Why CO2/O2 ?
Reply With Quote
  #10  
Old 06-18-2010, 07:53 AM
Smeghead Smeghead is offline
Guest
 
Join Date: Apr 2000
I think the water issue is at play here too. You don't want condensation on your fruit.
Reply With Quote
  #11  
Old 06-18-2010, 08:08 AM
DSeid DSeid is offline
Guest
 
Join Date: Sep 2001
Quote:
Originally Posted by indian View Post
[/B]

Why CO2/O2 ?
Fruit respire while ripening.
Reply With Quote
  #12  
Old 12-22-2012, 12:57 AM
TriPolar TriPolar is online now
Guest
 
Join Date: Oct 2007
Sunlight is the best ripener for avocados. In the winter time I might leave them on the window sill all day. In the summer just take them out for an hour or two, turn and another hour or two.
Reply With Quote
Reply



Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 06:55 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.

Send questions for Cecil Adams to: cecil@chicagoreader.com

Send comments about this website to: webmaster@straightdope.com

Terms of Use / Privacy Policy

Advertise on the Straight Dope!
(Your direct line to thousands of the smartest, hippest people on the planet, plus a few total dipsticks.)

Publishers - interested in subscribing to the Straight Dope?
Write to: sdsubscriptions@chicagoreader.com.

Copyright © 2013 Sun-Times Media, LLC.