Naked Science Forum

General Science => General Science => Topic started by: Henry Risha on 12/11/2009 10:30:02

Title: Which is a better buy - A small banana or, a large one?
Post by: Henry Risha on 12/11/2009 10:30:02
Henry Risha  asked the Naked Scientists:
   
Hi Chris,
 
Which is a better buy? A small banana or, a large one? Which one has the least skin?
 
Regards,
 
Henry.

What do you think?
Title: Which is a better buy - A small banana or, a large one?
Post by: Don_1 on 12/11/2009 12:34:46
I don't know if anyone has ever put this to a practical test, but I would think that the skin to fruit* ratio my be slightly higher for larger bananas, since the skin does appear to thicken as the banana grows.

Whether this difference is appreciable when it come to value for money, I wouldn't like to hazard a guess.

One thing is for sure though, if you live in the UK, or any other country where the banana is not grown, the fruit* you get will have been picked while still green, then shipped to a banana ripener in your country. Because they are ripened off the tree*, they are not as tasty as those ripened on the tree and consummed immediately after being picked.

*Bananas 'trees', as they usually referred to, are actually a herbaceous plant, not a tree. The banananananananana (sorry, got a bit carried away there!) can be referred to as either a fruit or a herb.
Title: Which is a better buy - A small banana or, a large one?
Post by: neilep on 12/11/2009 14:03:42
I worked on a kibbutz when I was 17...I climbed date trees and bagged banana trees/plants......which was nice !
Title: Which is a better buy - A small banana or, a large one?
Post by: Kerry on 12/11/2009 14:23:36
How interesting - I didn't know the banana 'tree' was a herbaceous plant!
Title: Which is a better buy - A small banana or, a large one?
Post by: neilep on 18/11/2009 16:50:55
If one assumes, for the sake of argument, the length of a banana equals 5 times its diameter (L=5D), then the surface of the cylinder

= 2(π/4)D + πDL = (π/2)D + πD5D = πD + 5πD = 5πD. 

The volume of the cylinder = 2(π/4)DL = πD5D = 2πD. 

The ratio of surface/volume = (5πD) / (2πD) ~ 2/D. 

Thus, for larger sizes (D), theres less surface per volume (2/D), meaning less "unedible" skin per volume (although the skin can be eaten).  Also, the skin contains esterified fatty acids, which can be used as a skin lotion to treat problem areas such as psoriasis.

However, as Don mentioned, the skins of larger bananas do seem disproportionately thicker than for smaller varieties.  Plus, small varieties seem "stubbier", that is, L/D seems smaller, giving the smaller fruits a lower surface per volume. 

This is a tough question to answer.  I think someone needs to buy both varieties, separate skin from fruit, weight each separately, compute averages, determine skin/fruit ratios for the varieties, and factor in the price per pound.  Ultimately determine the actual cost per pound of fruit.  Any takers?

How do "banana ripeners" work??

Perhaps ewe can get a grant or some sponsorship !...this could be important work ! [;)]
Title: Which is a better buy - A small banana or, a large one?
Post by: Don_1 on 18/11/2009 16:55:08
I think you may be told to 'stop monkeying around'.
Title: Which is a better buy - A small banana or, a large one?
Post by: Geezer on 18/11/2009 20:54:11
How do "banana ripeners" work??

I didn't know there was such a thing, but bananas do give off a lot of ethylene (oficially ethene). Fruit and vegetables ripen quickly when exposed to ethylene. The green plastic bags they advertise on the TV for keeping fruit and vegetables from spoiling contain an agent that neutralizes ethylene.

http://en.wikipedia.org/wiki/Ethylene
"Plants can be induced to flower either by treatment with the gas in a chamber, or by placing a banana peel next to the plant in an enclosed area."
Title: Re: Which is a better buy - A small banana or, a large one?
Post by: Bananaman on 31/08/2019 11:02:41
This post made me curious.  We eat a banana every day with our meusli so I weighed and measured every one, then the skin, and set up an Excel sheet to calculate the result;
A 27cm [10 1/2"](excluding stalk) has 3.5% more useful fruit, per gram, than a 19.5 cm [7 1/2"] banana. It is technicaly better, then, to get bigger ones but practicaly, best to just get the size to suit yourselves.  Incidentaly, the larger bananas had twice as much weight of useful fruit than the small.
Title: Re: Which is a better buy - A small banana or, a large one?
Post by: syhprum on 01/09/2019 17:43:44
As we are shortly to be liberated from the thrall of Brussels and will be free to buy bent ones, would it not be interesting to compare bent ones with straight ones
Title: Re: Which is a better buy - A small banana or, a large one?
Post by: flummoxed on 01/09/2019 18:12:49
As we are shortly to be liberated from the thrall of Brussels and will be free to buy bent ones, would it not be interesting to compare bent ones with straight ones

More Brexit nonsense http://www.europarl.europa.eu/unitedkingdom/en/media/euromyths/bendybananas.html You can still have your bendy banana and eat it, without Brexit.

The smaller bananas in my experience have more flavour. Would anyone disagree
Title: Re: Which is a better buy - A small banana or, a large one?
Post by: Bananaman on 02/09/2019 08:52:14
The bananas in the Canaries are a smaller variety and much sweeter. They don't export them as the rest of the world seems to want big ones, no matter what they taste like. The banana gets sweeter as it gets riper.  Personaly we like them best when freckled.
Title: Re: Which is a better buy - A small banana or, a large one?
Post by: flummoxed on 02/09/2019 10:39:47
The bananas in the Canaries are a smaller variety and much sweeter. They don't export them as the rest of the world seems to want big ones, no matter what they taste like. The banana gets sweeter as it gets riper.  Personaly we like them best when freckled.

It could be the volcanic soil that gives the bananas grown in the canaries and other volcanic islands the added flavour.

On Isla La Palma I am pretty sure they had some big ones as well in the plantations over towards Tazacorte, but yes the smaller varieties do appear to have more flavour than those available in most supermarkets.

When thinking which is better is it just size that matters or do other things like flavour come into the equation as well.