Berkeley Bowl Marketplace in Berkeley, California is justly famous for its vast array of produce and their avocado selection is no exception. They sometimes sell five or more different sizes — I have seen pee wee, small, medium, large and extra large. Of course, each size has a different price and they are always sold by the piece, never by weight.

Seeing the array of avocados, I wonder: 1) does the edible fraction depend on the size of the avocado? and 2) what are the relative costs of the different sizes? To answer these questions, I bought almost 20 avocados of various sizes and weighed them with and without skin and pit.

Weighing Avocados

I weighed 19 avocados: 6 large, 6 medium, 3 small, 2 pee wee, and 2 extra large. The results of my measurements are in the chart below. The x-axis is the weight of the whole avocado in grams; the y-axis is the percent of the avocado that is edible, by weight. The different symbols represent the different sizes.

The edible percentage is consistent, around 70%¹, meaning that the amount of flesh you get from a Hass avocado is relatively independent of the total weight.

The 70% result is consistent with UC Riverside’s Avocado Information site, which states that the seed, skin, and flesh percentages for Hass avocados are approximately 16%, 12% and 72%, respectively.

I don’t know enough about avocado botany to say why the flesh percentage is so consistent across avocado weights. It might be that as avocados grow, mass is added to the pit, skin and flesh at roughly the same rates. Or that when an avocado is ready to be harvested, the edible percentage happens to be around 70%.

Whatever the case, a key takeaway is that the heaviest avocado is likely to give you the most edible flesh, as opposed to a disproportionately large pit or thicker skin.

Avocado Cost Math

Since all sizes of Hass avocados have roughly the same edible fraction, it’s pretty easy to compare their costs.

For two avocados with different sizes and prices, weigh one or more from each size², then calculate two ratios:

1. ratio of weights, the larger avocado divided by the smaller
2. ratio of prices, the larger avocado divided by the smaller

If ratio 1 is greater than ratio 2, the larger avocados are a better deal.

For example, consider a $0.99 “large” avocado weighing 260 grams and a $0.89 “medium” avocado weighing 190 grams:

1. The weight ratio is 1.37 = (260 / 190)
2. The price ratio is 1.11 = (0.99 / 0.89)

Result: the large avocado is the better deal, with a cost of approximately $2.50 per pound of flesh vs. $3.02 for the medium.

Why Are Avocados Sold By The Piece?

As a final note for this post, here is an avocado mystery to ponder: Why are they sold by the piece and not by the pound? I personally have never seen avocados sold by the pound, and it doesn’t make a lot of sense — grocery stores already sell lots of different fruits and vegetables by weight. I asked the California Avocado Commission if there is a good reason for this, and they told me that it is completely up to the retailer to decide how to price their products.

Image Credits

• Photo of an avocado half from Andrea.Pacheco’s flickr collection, subject to a Creative Commons License.
• Photo of crocheted avocados from Regina Rioux’s Flickr account, used under a Creative Commons license. Find out how to buy the Avocado crochet pattern on her blog or Etsy shop.

Originally posted on 10/9/2010. Major update in 2018. 

Notes

1. Except for the small avocados, which had a far lower edible percentage. Perhaps I wrote down the wrong weight in my notebook.
2. Good luck trying to find an accurate scale at the grocery store. Perhaps weighing 5 of each variety will lead to better results on the produce section scales. Or you might find an accurate scale in the bulk section.