Temperate plants/trees that produce oils/fats that are solid at room temperature?

Most of us are probably familiar with a number of plants or trees with fruits/nuts that produce oils/fats that are solid at room temperature (coconuts, cocoa, shea tree). Obviously these solid, plant-based fats have many uses, from cooking, to cosmetic, to even industrial uses. So many homemade/natural/zero waste products rely on ingredients like these and they're great to have. But they're all sourced tropically. They could be grown in small numbers in hoop houses or green houses (depending on how "temperate" your clime), but I'm interested in whether there are plant based sources that could be grown further north, in the outdoors without (much) protection or pampering. There are Mexican avocadoes that can get down to 10 F and probably further with breeding, but something that separate cados from the above examples is how much more shelf-stable coconut, shea, etc. are.

It would seem crazy to me that out of 400,000 plant species, not a single temperate species produces a solid fat, but I suppose it's possible. And if that's the case, I wonder why that is? Is there something about the way plants like cocoa or shea make these oils, or their chemical structure, that could only occur in warmer temperatures? What might that be? Man, I should have gone into botany instead of the social sciences!!!


Note: Not interested in animal based sources like fat or butters. In the rough thought experiment that guides my interest in homescale permaculture (and even beyond my own moral and ethical issues with even the most benign animal-rearing) the reality is that the lower on the trophic ladder you are sourcing food and materials, the more intensive production can be, with the least consumption of water, nutrients, etc.  In the mostly suburban context of the USA, maximizing production on small spaces is important for "suburban retrofitting" IMO.

Thanks!

Very good question!!...I am not “science-y” so really cannot provide any insight!!

It's probably because they grow in a temperate climate. an oil that was solid in our climate would be very hard to move around a plant.

That's my thinking as well, but I don't know enough about where and when these fats are synthesized in the plant (e.g. the same combination of fatty acids that is in the coconut is not necessarily circulating around in the plant - they might synthesize in the fruit itself, so transporting them around the plant is not such a big deal. There are also places where coconut trees grow well. Also, the melting point of these oils is relatively high (coconut oil 76, shea butter in the 90s), yet there are climates where these plants grow just fine in quite low temperatures - there're coconut trees in Tampa, FL, where temperatures in the cold months are in the 50s on average, sometimes getting considerably lower. You'd think if it were a problem of the plant equivalent of arteries getting clogged, that it'd only live in the most tropical climates.

The fats are mostly in or around seeds, providing energy for new sprouts. Perhaps there is some metabolic advantage to the fats being liquid at sprouting temperature of the seed? Purely speculating.

Or maybe its just that you are really looking for a very specific intersection of traits that make a plant a commercially useful source of fat, and these traits may not bestow any evolutionary advantage on the plant. E.g. you're not just looking for a plant that contains some fat which is solid (but soft enough to be useful) within a specific temperature range (say 60-85 degrees farenheit), but also a fat which is readily extractable, edible to some degree, with a neutral or pleasant aroma/taste, and present in large enough quantities to be economically worthwhile. So maybe it's just coincidence that the few plant meeting all these criteria are tropical or subtropical.

For non-culinary uses, there are myrtle/bayberry shrubs that are a traditional source of wax in temperate climates.

Yeah, I'm leaning toward the latter - that it's essentially a miracle that even just a few plants have this exact mix of traits, and so much of our planet's biodiversity is concentrated in tropical hot spots that it's probably a matter of odds. Still an interesting question!

Great point on the bayberries - I was violating my own (only plant sources) rules and have been thinking about beeswax as a sensible replacement in cosmetics. It may be silly of me, but I just wasn't really thinking about waxes as a fat that shares similar qualities to these oils. But myrtle/bayberry wax pretty much checks off all of the boxes I'm looking for in that sense. I think I'll do a bit of experimenting with it! Thinking of waxes as having these similar properties definitely opens things up quite bit

For culinary uses comparable to how one would use butter, I also had a little flash of insight: in this whole thing I've been thinking about what temperatures these fats (coconut, shea, cocoa) melt at. I read an interesting article about how, because they are composed of several different chains of fatty acids, coconut oil and the like don't have one "melting point", and that different parts of the fats are actually melting at different temps. Beeswax candle making is the same way - beeswax melts between 145-150 F. Only thinking about the melting points, I was failing to think on the flip-side - what are the freezing/solidification points of other oils? There might be some that are liquid at "room" temp, but only because we generally only keep our rooms in the comfy 60 - 75 F range. Maybe there are some oils that are solid at 55 or even 60 and could just be kept in the fridge to be treated like butter in a spreadbility sense? A quick look at some common oils shows that avocado oil starts to solidify around 50 F, and peanut oil in the high 30s. Again, I'm counting avos because I've seen them survive into zone 8 (with plenty of protection). I'll post back here if I find anything interesting to add!

ust thought I'd update this for any folks in posterity who were interested - never went back and did so with my goldfish brain! Neal's idea to consider species that generate wax was a good one, so I decided to look into waxy species. I went on Plants for a Future, searched for 'Other Uses: Wax" and put in my zone info (7/8), and I went down the (very short) list of results to see if any had the fat listed as edible. The only possible candidate that came out of that search was Triadica sebifera, the 'Tallow Tree', and it seems like it checks all the boxes I was asking about:  it is highly productive and does produce an edible fat. However, Dean at Eat the Weeds Tallow Tree had trouble finding more information and much luck preparing it himself, and the only scientific journal articles I can find of making an edible fat from it seem to be industrial food chemistry folks, but the reports of its edibility date further back... another puzzle to solve! Wish I knew Mandarin!

Aware of it now, I can see most of the posts on PFAF include references to how invasive it is. It's always hard to judge through rhetoric how severe an issue is, and the USDA only lists it as moderately invasive, which is not the impression you'd get reading articles about it from state extension services etc. But I guess if it's invasive as the most fearful folks say it is, I won't have to plant any, because it will be growing here soon enough (currently it's restricted to zone 8 areas of N Carolina, but it exists in significantly colder ranges in E Asia).

At the very least, I'd say this tree puts to bed the theory that climate necessarily precludes plants producing solid, edible fats. Seems the tropical biodiversity argument was the better explanation.

Couldn't figure out how to just edit my last reply, so here's just some more info:

1) Wow, no joke about it being here soon: I found a scientific paper from 2011 saying it's most northern range at the time was Wilmington, NC. Reports on iNaturalist now show verified observations https://www.inaturalist.org/taxa/79388-Triadica-sebifera near Richmond, VA. At this rate I'll be harvesting tallow wax here in NJ by 2030.

2) Found a patent granted in 1989 to a team from Japan for making 'hard butter' from the seeds: https://patents.google.com/patent/US4844940A/en. To get to behave like butter, you can apparently fractionate it through 'winterization' - i.e. cool it down slowly and then remove the crystals that form at different rates. All that being said, virgin coconut oil is unfractionated and still has a shelf life equal to or better than refined coconut oil. I guess the only reason you'd want to do this is for aesthetic preference (more neutral taste - maybe tallow tree tastes bad?, color, etc.)

That's all for now :D

In my forays into temperate waxes and oils, besides Bayberry and related species, Sumac (Rhus.) species are remarked to produce a vegetable tallow. When pressed from the seeds, the oil is solid at room temperature and was used as a means of candlelight, likely being equivalent in preference to rushlights. Staghorn Sumac (Rhus typhina), is an excellent species that grows vigorously and sets seed abundantly. The seeds of the related Winged Sumac (Rhus copallina) are remarked by Green Deane to be edible when ground into a powder, but seed edibility for different Sumac species or their oil specifically seems murky. Luckily the tannins in the seeds are not fat-soluble and won't taint the flavor of any oils produced, similar to how red oak acorns and bitternut hickory can be pressed for oil without removing tannins from the nuts first. It may not be for you, but I wanted to let you know!

Eric S.

This was a great topic to read through.  I am in Zone 6a and after watching so many tropical cultures harvest cooking oil as well as oils for cosmetic use (shampoo, conditioner etc) from native plants, I had the same question.  The only plant we could use that I know of, is the peanut.  I’m not sure if the nut is the healthiest for cooking, but know it is useful for its ability to withstand higher temperature cooking.  I’d need to find out how it affects human pores, its long term effects on the body internally and when it becomes an unhealthy fat,  and whether there is a way to keep someone with a peanut allergy from experiencing an attack etc.  Mostly, I wish there was another plant source we could tap for oils/fats, in the colder zones.   Anyway, please keep adding to this topic as you find info.  This was the best reading I found on the subject.    

I don't know if it's helpful but Sea Buckthorn seeds are said to have 7–11% oil.

As was alluded to upthread, fractionation  ("winterization") may permit separating the higher melting point constituents from the lower fairly easily, and with relatively low energy input (similar to making apple jack versus distillation).

I am able to purchase fractionated coconut oil which will remain liquid even at refrigeration temperatures.  I don't recall for sure, but I think the label spec'd capric and caprillic acids as the ingredients.  I don't have it in front of me at the moment.  The heavier (longer chain, I presume) fractions must get used elsewise - confectionery applications, I'd presume.  I had been using the low wax point stuff to increase the oil content of my lunch salads, because I am trying to follow a fairly rigorous ketogenic diet to address a specific health concern.  The lack of calories from dietary carbohydrates requires that I obtain energy from good fats to maintain body weight (I'd prefer to not lose much more, and certainly don't want to lose any muscle mass, at this point).  I think I'll shift to avocado or olive oil for my salads, and see if I note any differences in my health (I have no specific concerns, this is just a "what if" experiment).

In any case, fats from natural sources are likely to contain a number of chemical constituents.  Cold fractionation would allow one to skim off the ones with the highest melting point.

Linseed oil reportedly contains about 7% palmitic acid, and 4-ish percent stearic acid.  Flax is well adapted to temperate climates.  Not sure how to get the stearic acid, whether cold fractionation would be an efficient means of doing so, or not.  Sunflower seed oil usually contains 5-8% palmitic acid, but a specific commercial cultivar (CAS-5) contains about 25% palmitic acid.  Again, sunflowers are well adapted to temperate climates, and cold fractionation might be possible here, too.

I'm just spit balling on this, using my best Google-foo, and haven't tried any of the above.