© Denzil Green
The Avocado tree is a tropical evergreen tree distantly related to the Laurel bush (bay leaf bush) and to the cinnamon tree (in fact, avocados are susceptible to a root rot disease called Phytophthora cinnamomi.) Leaves of some Mexican varieties of avocado trees are even aromatic enough to be used in cooking.
Left on its own, the avocado tree could grow 60 to 80 feet tall (18 to 24 metres), but in orchards its height is kept down to about half of that to make the fruit easier to harvest. (Coincidentally, the Dutch introduced the same technique of keeping cinnamon trees short to make them easier to harvest.) Avocado trees need anywhere from 4 to 7 years before they will start fruiting in any useful quantity.
Avocado grown from seed rarely produces good-tasting fruit; commercially, it is propagated by grafting.
Unlike many fruits which will not ripen after they are picked, avocados will not ripen until they are picked. Consequently, growers simply let some varieties, such as Reed Avocados, sit on the trees until needed. Picking them hard probably actually suits producers just fine, as it makes them less of a worry to ship. The avocados are shipped in coolish containers so that they don’t ripen during shipping, and arrive ready at the stores for final ripening at home by consumers.
When fully ripe, the hard flesh will be soft and spreadable, almost like butter once mashed. The flesh is usually deep green near the skin, but lightening to shades of yellow or green towards the stone in the centre.
Types of Avocados
There are 3 basic families of avocados: Mexican (Persea americana var. drymifolia), Guatemalan (Persea americana var. guatemalensis) and West Indian (Persea americana var. americana.) Any of the hundreds of varieties available today will have descended from these families. Some of the varieties don’t even have real names yet, just being referred to by terms such as HX38 or NB86.
- Guatemalan descendants tend to produce warty skins that are green, black or purple, and larger than Mexican descendants, but not as large as West Indian ones;
- Mexican descendants can produce the smallest of avocados with thin purple or black skins and yellowish-green flesh. Leaves of some varieties can be used in cooking;
- West Indian descendants tend to produce fruit that is the largest of all avocados with smooth, glossy, lighter green skins (the term “West Indian” is probably too late to change now, but it is hopelessly inaccurate: this type of avocado appears actually to have originated on other side of Central America, in lowland areas on the Pacific Coast.) These avocados tend to be lighter in overall oil content.
If you are in North America, your avocados probably mostly come from Florida or California. Since 1914, California Avocado growers have lobbied vigorously to keep Mexican-grown avocados out of the American market on grounds of pest and disease transfer. There are some reports that, while continuing their lobbying efforts, some have as of 2000 also set up in Mexico and are importing Mexican Avocados to America under their American brand names.
If you are in the UK, your avocados probably come from South Africa during the summer months, and from Israel or Spain the rest of the year (Marks & Spencers introduced Israeli Avocados to the UK.) Avocados tend to be eaten steadily throughout the year in the UK, while in Europe preference for them declines during the summer.
If you are in Australia, your avocados probably come from within the country or South Africa.
Here is a brief listing of varieties being produced in some countries:
- Spain: Bacon;
- South Africa: Edranol, Fuerte, Ryan;
- Israel: Fuerte, Hass, Ettiner, Nabal, Benik, Ettinger, Nabal, Pinkerton, Reed, Wertz;
- California: Most varieties grown in California are of the Guatemalan and Mexican type, as they are better suited to the California climate. Best known are Hass and Fuerte;
- Florida: Most avocados grown in Florida are varieties of the West Indian type (smooth skins), as they are better suited to the Florida climate. Though they are larger and less expensive than the Californian varieties, Florida varieties don’t have the nice, nutty taste that California ones do. Florida varieties have less fat in them than California varieties (never mind that it is a beneficial kind of fat that our bodies need), so Florida has tried to use this one so-called advantage in their favour; some brands are even marketed under names such as Lite Avocado and Brooks Lite. Mind you, all of that being said, the reason they contain less fat ounce for ounce compared to California Avocados is that the Florida Avocados are larger and more watery, so the fat is spread out over a larger fruit.
Avocados are rarely found ripe and soft in the stores. They’re ripe when they yield to a gentle squeeze on the rounded end when cradled in your hand. Avoid avocados where you can sense large soft spots or gaps below the skin: those will be bruises.
Usually, you have to buy them 2 to 5 days in advance of using them. (Which is tough luck on the old, last-minute guacamole ideas.) Let them ripen at room temperature, on a table, counter or window ledge. There’s no really quick way to ripen an avocado. Some talk about ripening it in the microwave with a zap for about a minute, but all that really does is soften it and you run the risk of it turning a little bitter on you. The flavour won’t have ripened at all, either. What may speed the ripening (by a day or so) is ethylene gas, such as is produced naturally by an apple or a banana. To try your luck at this, put the avocado in a paper bag (they will never ripen in a plastic bag) with an apple or a banana and let sit at room temperature. This should take anywhere from 1 to 3 days.
Even though many people love Avocado, this is why they seldom have it — having to plan several days ahead when they might feel like it. You can’t just act on a whim. Producers are looking at vacuum packing whole ripe Avocados and Avocado purée so that consumers can have access to a ready-to-use supply. Commercially, Avocado pulp with no preservatives refrigerated in vacuum-sealed bags is already available to Mexican food restaurants; it has a 30 day shelf life unopened.
In 2011, the Morrisons grocery chain in England announced that it was going to sell avocados in a new format: the Haas avocados are grown in Peru, harvested at the peak of ripeness, peeled, pitted and vacuum-packed in a see-through pouch, then shipped to England.
To use, cut them in half lengthwise, cutting around the seed. Pry the two halves apart. Use a spoon to get the large pit out of the half that still has it. Use the spoon to then scoop out the Avocado meat.
Discard the skins and the pit; we haven’t heard of anyone eating them, but we think it’s a safe bet to say that they would be uninteresting in any way, shape or form.
If you’re making a bacon, lettuce and tomato sandwich and have a very soft avocado on hand, instead of buttering the toast or bread with butter, use the soft avocado instead.
We have been used mostly to eating avocados raw but recently (2004) many recipes are emerging involving cooking Avocados. In fact, the old myth even said not to cook avocado, as it would go bitter. What makes it go bitter, in fact, is prolonged cooking. So you either add it at the end of cooking, or use it in something that is just in the oven for a short while. When you are adding avocado purée to soups, always add it at the end: you can re-heat the soup through, but never let it boil again.
Heat grill to medium-high. Wash avocados, slice in half, discard pit (leave skin on.) Lightly spray or brush the exposed avocado halves with oil. Place the halves cut-side down right on the grill. Do not turn, but lift occasionally to check for grill marks developing. Don’t cook for more than 5 minutes. Remove from grill, let cool a bit. Then use as desired: serve each half whole with a spoon to eat out of the skin, or, remove from the skin, and slice for use as a side, in salads, or for a somewhat smoky tasting guacamole, etc.
Preventing Avocado from Browning
Be aware that avocados will start to brown from the moment they are cut open and exposed to air, so either serve right away or use a technique to help slow the browning. Most people recommend using some kind of ascorbic acid such as lemon juice, though many people prefer lime juice as it seems to complement the Avocado flavour without changing it. In fact, though, any of the techniques used to prevent Apple Slices from browning will work for avocado. See the page on Apple Slices for further information.
Some dieters who are strictly concerned with weight loss avoid avocados, as they are high in fat — the fat content is about 20%.
Even though California avocados seem have twice as much fat per oz as do Florida ones, bear in mind that in the Florida avocados the fat is spread out over more ounces.
The fat in avocados is largely monounsaturated, which actually benefits your body and your heart in particular. Of the 22.5g fat in 1 whole small 150g / 5 oz avocado, 2.5 g is saturated, 2.5 g is polyunsaturated, and 15g is monounsaturated. 
Contain good amounts of folic acid, fibre, potassium, and vitamins B6, C and E.
1 lb = 450 g = 2 medium size Avocados = 1 large one = 2 1/2 cups chopped or sliced = 1 1/2 to 2 cups mashed
2 to 3 thin slices = 2 tablespoons
1 300g (10.5 oz) avocado, unpitted = 230 avocado (8 oz), pitted
Once your avocado has ripened, store it in the fridge for anywhere up to five to seven days (depending on just how ripe they were when you put them in.) Whatever you do, do not place a hard avocado in the refrigerator. When they are stored below 45 F (7 C), they will darken and go black — but still not soften.
Contrary to popular use, you can freeze avocado. Not whole or in slices, or in any way that you’d want to use in any kind of “solid” way afterward, but rather as a purée that you can use as a salad dressing, sandwich spread or base for a dip such as guacamole. Start with soft, ripe fruit. Remove the flesh into a bowl, mash with something acidic such as lemon or lime juice (use 1 tbsp per two avocados). Pack into plastic container with a lid, leave a bit of room at the top for expansion during freezing, and freeze for up to 5 months. Plan to use the purée within 3 days at most after thawing it; if there’s a bit of water in it, just tip the container and drain it out.
It is an urban myth that putting the avocado stone in your dip or guacamole will keep it from browning. The only part that won’t go brown is the part covered from the air by the stone! Put your trust in plastic wrap instead.
To help prevent browning of the guacamole or any dip that you have made a bit ahead of time, put plastic wrap directly on the surface on it so that no air gets at it. What turns Avocado brown is oxygen in the air.
Avocados have been grown in Central America for a long time, perhaps since 5000 BC. Avocado seeds have been found buried with mummies in Peru dating from the 8th century BC. Aztecs called the fruit “ahuacatl” — “testicle” — because of the shape (and the shape would be???). Perhaps for this reason, it was also regarded as an aphrodisiac.
Avocado orchards were first planted in Florida in 1833 and in California in 1873.
Literature & Lore
“Avocado was the table aristocrat of the twenties, exotic, expensive. Once a single fruit cost a dollar and over. Once it was eaten only in salad or au naturel. Now it fits obligingly into any part of the menu from soup to ice cream. It was the avocado growers who taught cooks in the States to use this fruit of the strange meaty flavor, the day-by-day food in countries south of the border.
Fruits of the first commercial groves in California and Florida went only to tables in top-flight hotels. In the retail markets the avocado made a slow start. To speed matters the growers trained a crew of “avocado preachers” to teach the public what to do with those crazy-looking things called “alligator pears.” So the avocado got going. Statistics tell the story. In 1925 but 200,000 pounds of the fruit were sold in this country. In 1946 sales passed the 20,000,000-pound mark. This year the avocado crop is expected to hang up a new record.” — Paddleford, Clementine (1898 – 1967). Food Flashes Column. Gourmet Magazine. March 1947.
“Thou green avocato, charm of sense…” James Grainger, in “Poetical Translation of the Elegies of Tibulles”, London, 1758.
“The Aguacat no less is Venus Friend
(To th’ Indies Venus Conquest doth extend)
A fragrant Leaf the Aguacata bears;
Her Fruit in fashion of an Egg appears,
With such a white and spermy Juice it swells
As represents moist Life’s first Principles.”
— Cowley, Of Plantes, v.
In French, the word “avocat” is used for both lawyer and Avocado, which can lead to some zany mix-ups in computer translation… “slice the lawyer in half…”
The English plural of Avocado is Avocados, despite the temptation to pluralize it as we would tomatoes or potatoes.
The Spanish adaptation of this word was “aguacaté”, which lead to our word “guacamole.” The “mole” part at the end means “sauce.”
At one time a somewhat popular name for Avocados was “poor man’s butter.”
 California Avocado Commission. Retrieved January 2013 from http://www.californiaavocado.com/nutrition/. They give the weight of a whole avocado as being around 150g / 5 oz.
Moore, Leslie. Guacomole Wars. In “Latin Trade”. June 2000.
Reich, Lee. Growing Avocados from Seed. California Rare Fruit Growers, Inc. 1998. Retrieved December 2010 from http://www.crfg.org/tidbits/AvocadoFromSeed.html
University of California, Agriculture and Natural Resouces. Avocado Varieties database. Retrieved Feb 2004 from http://www.ucavo.ucr.edu/AvocadoWebSite+folder/AvocadoWebSite/AvocadoVarieties/VarietyFrame.html
Supermarket reveals the avocado that’s always perfectly ripe… pre-packaged and ready peeled. London: Daily Mail. 16 November 2011
Vizcaino-Lico, Kendra. 10 Foods You Didn’t Know You Could Grill. Gourmet Live Magazine. 18 July 2012. Retrieved August 2012 from http://www.gourmet.com/food/gourmetlive/2012/071812/simple-grilling-recipes