Big Fat Problems
A couple of weeks back, I spent some time with a young development chef who had just moved across from working in a high-end restaurant. It was clear that, despite being super-talented, this young chef had a lot to learn. His is a common career progression, but the transition from restaurants to development kitchens is always a leap. Although both types of chef are united by a love of food, we work in very different ways.
Many of these differences were apparent in the day I spent with him, but the one that really stood out was his liberal use of fat. I had almost forgotten how much fat professional chefs use, adding extraordinary amounts of butter to sauces and purees, enriching pasta dishes with gallons of olive oil, roasting vegetables in liberal chunks of animal fats, and reducing double cream, just in case it wasn’t rich enough.
Of course, this made his cooking incredibly delicious, but if you want to understand why restaurant food is so often tastier than home cooking, watch how much fat (and salt, but that’s another story) professional chefs add to dishes. And if you want to know why the prepared foods you buy in the supermarket aren’t ‘restaurant quality’, get some of your favourite restaurant dishes nutritionally analysed to see how much fat, saturated fat and calories they contain. My new colleague will soon come up against nutritional targets for retail products and may well have to relearn a few things.
Fat is delicious. It is nowhere near as essential in our diet as some low carb diet advocates claim (in fact, saturated fats are not essential at all), but when it comes to motivating us to choose a food product, there is little more effective. It is highly energy dense, with twice as many calories per gram as sugar, and too much in your diet is probably a bad thing. But at every level of cooking, fat is an important tool in making food more palatable, more desirable, and more compelling.
Fat is largely responsible for meat and dairy being such delicious food choices. Protein doesn’t really taste that great, especially on its own, but clever use of fat can make it delicious. Animal based fats tend to carry flavours that we enjoy, but also have other physical properties that make them desirable. They are often solid at room temperature, which means that they are useful for various types of baking, but this also gives them a richness and mouthfeel that liquid oils just don’t have. And when fats melt just below human body temperature, as is the case with butter and some animal fats, that gives them a particular appeal, delivering near irresistible sensory pleasure.
When it comes to meat, fat has a unique flavour and functionality. Most of the fat in meat is solid at room temperature, and particularly so under refrigeration, but will melt out during cooking. Small pockets of solid animal fat in a piece of meat will become liquid when heat is applied, adding flavour, richness and crucially succulence, in a way that vegetable oils just cannot match. It is that succulence and ‘sizzle’ that you get from burgers, sausages and steaks, that makes them very hard to replace in our diets.
If you make a vegan burger, then you usually try to add a level of fat similar to that found in a conventional meat product (this varies but is often around 15% in premium versions). The problem is, if you just add an equivalent quantity of vegetable oil, it will emulsify into the burger mix. This makes for a slightly strange product which lacks succulence and ‘sizzle’, with a tendency to be rubbery, oily and quite unpleasant to eat.
The alternative is to use a hard vegetable fat that can be broken up into pieces and added to the cold mix without it emulsifying. These small pieces will then melt as the burger cooks, so adding succulence, and sizzling pleasantly as the product cooks. There are plenty of hard vegetable fats available to choose from, and these also find uses in baking, confectionary, chocolate manufacture and deep fryers. They are also in considerable demand for other industrial uses, particularly in cosmetic and skin care products.
Fats that are solid at room temperature are generally high in saturated fats. The rigid structure of long, straight carbon chains saturated with hydrogen makes them sit nicely together at lower temperatures, forming hard crystals. Unsaturated fats have carbon chains that are a bit wigglier (a technical term), and so only form solid crystals at lower temperatures.
(I am of course simplifying for the purposes of a blog post here so don’t @ me - the reality is far more complex, depending on carbon chain length, where the unsaturated bonds are on the chain, which chains are together on the triglyceride etc etc)
This is a problem. Saturated fats are delicious and useful in cooking, but consuming them in large quantities is probably not ideal for our health. There are nuances regarding how long the carbon chains are (lots of details on this in the first Angry Chef book), but in general, limiting saturated fat consumption is probably a good thing. There is an argument that saturated fat from plant sources might be worse for you that animal versions when consumed in the same quantities, largely because of the different lengths of carbon chains, although that is something I don’t want to get into here.
The other issue is where all this fat is going to come from, especially as the demand for plant-based foods increases. Because plants cannot control their temperature, the only plants that naturally produce large quantities of hard, saturated fats are those that grow in tropical regions. In more temperate climates, seeds have liquid oils with less saturation to prevent them going hard within the plant. The most commonly consumed hard vegetable fats such as palm, coconut, shea and cocoa can only be grown in the tropics, which is why they are collectively referred to as ‘tropical oils’.
The issue here is not just one of food miles. Fats can be processed and stored safely, so shipping them around the world by boat will not significantly add to their carbon impact. More importantly from an environmental perspective, as demand for these fats grows, demand for land to grow them on increases. Right now, if we want to expand production of tropical oil crops, the only way to do so is to cut down virgin tropical forests, driving one of the most significant and irreversible environmental disasters of all time. The soya, cattle and other types of agriculture that are causing significant habitat destruction in tropical regions can all be produced elsewhere. But when it comes to tropical oils, the clue is in the name.
What can be done? Saying we should just reduce demand is easy, but not practically achievable, unless we remodel the entire food system and dramatically alter demand for cosmetic and household products. Alternatives such as tallow (beef fat) or dairy fats have their own sustainability and ethical issues. We can certainly do things to improve the production practices of existing tropical oils, such as championing sustainable palm production, improving existing plantations, and guaranteeing that virgin forests are protected, but these approaches have their limits. Certified sustainable products make us feel good about ourselves, but often create a two-tier market, where cheaper and less ethical production happens alongside certified farms, with even less regulation than before. Coconut and shea production currently appear to be well managed, but it remains to be seen what will happen as demand for these oils rises. Coconut production in particular is messy and dangerous, with a history of animal and human exploitation.
There is of course an alternative, something that we have known about for over a hundred years. You can easily convert temperate grown liquid oils such as soya, sunflower and canola into hard fats, suitable for baking, spreads, confectionary and any other uses. The problem is, this process, known as hydrogenation, is one of the most feared in the industry. I have been involved in dozens of projects to remove hydrogenated vegetable fats from food products, and they are now largely absent from UK grocery. I have even been involved in campaigning to have them removed from fast food businesses, especially fried chicken shops, where they remained hidden in the UK food chain long after they had been taken out of retail products.
The issue with hydrogenation is this. If you have an unsaturated fat and want to make it more saturated, you need to add hydrogen to the carbon chain, turning double bonds between carbons into single bonds. You rarely want to completely saturate all the carbons in the chain, because then you will make an extremely hard fat that is of little use to anyone. So instead, you partially hydrogenate it, adding just enough hydrogen and saturating just enough bonds to produce a fat with the desired properties. This is a chemical modification, which means that your ingredient is no longer considered a natural ingredient and cannot be referred to as such on labels.
This was done for many years in the food industry, and the resulting products were often sold as a healthier and cheaper alternative to animal derived fats. Margarines were made as butter replacements, pastries used hydrogenated fats instead of lard, confectionary used vegetable fats instead of cocoa and cream. The key benefit, especially in bakery, was functionality, making complex layering and lamination processes far easier, producing cheap long-lasting fats with predicable physical properties and consistently neutral flavours.
These fats are largely similar to animal derived products, apart from one crucial difference. The process that hydrogenates the unsaturated fats also produces an unusual effect on any double bonds that remain. Animal derived saturated fats, and the saturated fats in tropical oils, have double bonds that are largely in the cis orientation. But partial hydrogenation produces a large number of double bonds in the trans orientation, with exactly the same chemical composition, but arranged as a mirror image. Although trans fats are produced naturally by the action of bacteria and can account for as much as 5% of the fat in some meat products, the levels found in partially hydrogenated vegetable fats is often much higher, sometimes approaching 50%.
For years this was not thought to be of huge significance, because cis and trans fats have extremely similar physical properties. But ground-breaking work in the 1990s identified a relationship between high consumption of trans fats and cardiovascular disease, leading to widespread reformulation of products to remove them. The identification of the harms of trans fats is considered to be the biggest, and perhaps the only, win for the science of nutritional epidemiology. The widespread move away from partially hydrogenated oils, at least in a small handful of developed countries such as the UK and US, has likely saved many lives.
There has been a cost. Demand for delicious food products has not reduced, and so natural alternatives to trans fats have been required, which largely means tropical oils. Palm has its own sustainability and health issues, and coconut has associated problems, including a stronger inherent flavour that makes it harder to deodorise, and a terrifyingly high level of saturated fat. It is perhaps no coincidence that coconut oil producers went to great lengths to sponsor influencers touting dubious health benefits for coconut oil at roughly the same time the industry was looking for hard fat alternatives. As stories appeared in many newspapers about the potential health harms of coconut oil in cinema popcorn, a group of unqualified, unregulated advocates simultaneously started spouting garbage pseudoscience and claiming coconut fat was a miracle superfood, presumably in an attempt to head potential health scares off at the pass.
This shift in fat consumption, characterised by an increasing demand for tropical oils and consumer rejection of palm, has pushed us towards a less sustainable fat supply chain. As demand rises, it is likely that this shift will continue, increasing the ethical issues, the destruction of natural habitats and the carbon cost. A move back to animal fats is not the answer, because when produced at scale, these place an even higher toll on habitats and climate. But unless we are planning to reinvent our food system, hard fats will need to come from somewhere.
There are alternatives, but they are not always acceptable to consumers. Because the trans orientation only exists in unsaturated carbon chains, it is only partial hydrogenation that leads to the creation of trans fats. Fully hydrogenated fats can be combined with un-hydrogenated liquid oils to produce trans-free fats made entirely from temperate grown oils. Although not new science, this is potentially a ground-breaking approach, but consumer and industry push back means it is unlikely to be accepted. The public is just not ready for the message that some hydrogenated fats might be okay, especially when these blends, which still contain lots of saturated fat, are never going to be sold as a health food.
It may soon be possible to produce fat in culture, genetically modifying yeast and bacteria to produce analogues of animal fats. It is doubtful however that this approach will be more acceptable to squeamish consumers, especially as livestock industry lobby groups start to talk about mutated Frankenfats. There are some non-GM yeasts that can produce dairy-like fats in culture, but these will never be as clean as vegetable fats and are unlikely to have enough useful functionality to replace them in baking. It is also the case that producing large amounts of any food through fermentation requires huge amounts of complex, expensive infrastructure, often making it inaccessible and difficult to scale. True solutions to global food issues are almost always ones that can be grown in the ground.
I believe that the issue of fat is one of the most pressing in our modern food system. I can see achievable solutions to the protein problem, with the development of new crops and the manufacture of new ingredients. But fat is far trickier. Fear of solutions not considered ‘natural’ is driving the market for tropical oils, and the plant-based industry is allowing this because it helps increase the palatability and acceptability of plant protein. We will never persuade consumers to eat foods that are not delicious, so fat is a problem we need to overcome.
This issue is a good example of how the natural fallacy, a belief that natural is always better, can have environmental harms. The drive to remove trans fats from food was almost certainly a good thing, but there is an argument that we did not fully appreciate the implications. The demonisation of everything ‘hydrogenated’ has put the industry in a difficult position. There has even been a drive to remove ‘hydrolysed vegetable protein’ from food products, as it has a vaguely similar name and is considered harmful by association.
A sustained focus on palm and hydrogenation is hiding greater issues within our fat supply chain. Unless we do something soon, our dependence on tropical oils has the potential to cause irreparable environmental harm, alongside ethical and human rights issues on a huge scale. Solutions exist, but until consumers and industry accept them, they are of little use.
