Dr Samuel Furse

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As a geeky teenager, I used to read the nutrition information labels on foods for entertainment.  Early on, I noticed a few things that sounded somewhat peculiar out of context.  For example, I was stuck by how difficult it was to guess what a food was from its nutrition information.  This worked both ways though: what foods had in them was quite difficult to guess just from knowing about them.  Years later I realised that this is the sort of thing that some food scientists work on.  I learnt that we have ended up thinking that water is the healthiest food around, chiefly because it has nothing in it.  I also saw that olive oil is only ninety-something per cent fat.  Sugar, on the other hand, is a full one hundred per cent carbohydrate.  Health benefits aside, I was immediately intrigued by this revelation.  (a) Why was something called ‘oil’ not completely oil, and (b) How could manufacturers get away with olive oil not being the full monty? Looking at different bottles, to see whether it was just that one I found out that some were 85% fat and some were more like 95%.  This prompted my third question (c) Why did it vary so much? The difference between 85 and 95% at is a bit of a shift for something that has the same name.

It was my first inkling that both marketing and food scientists had a lot to answer for.  However, the drama was moot in any case: TV chefs rattled on as much about good ingredients then as they do now, and cheap stuff was not as good as expensive stuff then either–so the chances were we were not being duped on a big scale.  The question remained though: What is the stuff in olive oil that is not fat?  What we need to do to answer this question is a bit of scientific analysis.

Nuclear Magnetic Resonance (NMR) Spectroscopy tells us that the dominant compound in olive oil is a triglyceride made, mainly, of unsaturated fatty acids. A typical triglyceride is shown in Figure 1.  One of the other ways we know it is a triglyceride, and the method used before NMR was invented, is by studying how it reacts with other chemicals.  Specifically, if one part triglyceride reacts with three parts of potassium hydroxide, to give three parts fatty acid and one part glycerol, it was seen as bona fide triglyceride.

Figure 1. The saponification of a triglyceride (top), giving rise to glycerol (bottom left) and three moles of fatty acid (bottom right).

 This reaction (Figure 1) is also the key to why olive oil is only ninety-odd per cent fat – apart from the green colouring. A calculation of the molecular masses tells us that glycerol represents around 10% of the mass of triglycerides, which is not a fat. This is why olive oil is not 100% fat. Expert bakers will tell you that glycerol, also known as glycerine* is quite sweet to taste and dissolves in water. It is also used to stop icing becoming dry and brittle. It is thus not a fat, and so is not listed under the fat content on the nutrition information.

When I realised this, I was a bit surprised at my original view. My reaction to the contradiction I first saw had been turned inside out. Now I know that olive oil that does not have 100%, or nearly 100% fat in it, because it is principally composed of triglycerides rather than fatty acids.  As this means it has probably seen less processing than other foods, it is therefore likely to be of a better quality. This also reflects well on the materials used to make it, because good olive oil does not need to be processed at all.

*Also used to make nitro-glycerine, the explosive that is in dynamite. 

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Figure 1. The “Pure Lecithin” produced by Ransom™ Image © Samuel Furse MMXI

It is not very often that something is so clearly adrift that I think it needs critical analysis.  This, however, is one of those times.  “Pure Lecithin Granules” produced by Ransom™ is a very innocent-looking product (Figure 1).  So what is there that could be to discuss?  I could be about to examine Ransom™’s legal position with respect to this product, or their marketing, or their science.  The label is green and yellow, and it has pictures of clean-looking vegetable matter on it (see photograph Figure 1).  So they probably have their marketing fairly well nailed.  I am not trained in law at all, and so that aspect I leave alone at present.  That leaves us with the science. The first thing that caught my eye was the phrase “Pure Lecithin”.  In lipid chemistry (and membrane biophysics) the term ‘lecithin’ means phosphatidylcholine.  This is bourne out by the products available from reputable suppliers such as this one and this one.  ‘Lecithin’ is an informal word and so there is some flexibility over its meaning, but this only extends to the detail of the fatty acid residues  (Figure 2).  This is where the use of the word ‘pure’ by Ransom™ meets its first serious slippery patch.  Lecithin is by definition a mix of phosphatidylcholine molecules, thus a concept of ‘pure’, seems at best imprecise.  Further, the very detailed nutritional information on the packet shows that there are at least four molecules present that are not phosphatidylcholine (‘real’ lecithin).  Three of these are the lipids phosphatidylinositol, phosphatidylethanolamine and phosphatidic acid.  The fourth is listed as “carbohydrate”, and is presumably yet another mixture.  Thus ‘purity’ with respect to this product is therefore debatable. The second phrase that leaps out with crashing force is “helps in the breakdown of fat”.  That suggests to me, as a consumer, that this stuff will not only help your body deal with fat in a way that is harmless to you but also basically reduce the amount of fat you will gain from the food you eat.  This phrase is therefore a good piece of marketing — it sounds good, but means almost nothing. What is true is that this collection of lipids (with a bit of carbohydrate), will help to dissolve fatty materials in water and form an emulsion of the fat and the water.  The “Lecithin” is therefore an emulsifying agent.

Figure 2. Phosphatidylcholine (Lecithin). The red section represents the hydrophilic (water-loving) section, where the blue represents the greasy-loving section. The latter is typically a mixture of types in lecithin.

It is perhaps not surprising that it has a molecular structure that is chemically sympathetic to both water and fat.  It is well known that water and fat do not mix.  That lipids allow this to occur makes them the metrosexuals of chemistry in that sense.  However, the fact that there are similarities between lipids and fats might ring alarm bells for you.  And you would be right.  As it happens, the molecules that make up fats, called fatty acids, form part of the molecular structure of lipid molecules.  In fact they are the weightiest part (see Figure 2).  This is why this “Pure Lecithin” is in fact 91% fat by mass.  So much for helping with the breakdown of fat, and being good for a healthy diet. 

So after deconstructing their presentation of anything even vaguely scientific, or indeed apparently healthy, do I have anything good to say about this product?  Well, sort of.  Mixtures of lipids are occasionally useful to me as a research scientist, with known components such as this it can provide a vague sort of comparison for other, unknown, lipid systems.  It provides a cheap source of such a mix of known lipids and so ideas about lipid experiments I have in the bath or at other inopportune times can be tested without spending much money.  But would I use it in food?  Certainly not.  It smells of nasty paper glue in my opinion and gets awkwardly sticky if it goes near water, even if we ignore the above shortcomings.  It may seem unkind, as they clearly go to some trouble to produce a food-grade product, however when something appears ill-presented on close inspection, could I really trust it?  Fat chance.

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Everyone thinks Morrisons is for cheap northerners. At least, according to a recent report, Morrisons think that people think that they are for cheap northerners. So, they have started selling black Italian truffles.

Said truffles are a mere snip at £99/kg. Well outside the budget of the average cheapo lard-arse from the north east. Outside the budget of the average cheapo lard-arse from anywhere in the Western world, come to that. Is there a burning desire for black Italian (got to be Italian) truffles in Kirkstall? And sufficiently more there than in York, Harrogate, or Hull, to require they stock it there only? Of course not. Perhaps it is because the competition in those other cities is too strong. Certainly they undercut Waitrose whose truffle effort costs a hair’s breadth under £400/kg, and they are not even fresh. Selfridges do nothing at all in that way (at least not online), and neither do Harrods. Although as far as the latter is concerned, you will be pleased to hear that you can get a truffle shaver from them, should there be such an emergency.

Perhaps I am barking up the wrong tree slightly though. Perhaps they have researched their market really carefully and there really is a demand for fresh truffles in Kirkstall. I cannot really say whether that squares with my own ideas, as I have never heard of the place. So when I say this is clearly a marketing gimmick, I may be wrong. But I do not think I am. The fact that it has been reported in at least one national newspaper and also in this article has got to be worth a couple of hundred quid of anyone’s marketing budget. And in order to achieve that, what have they had to do? Buy in 2 kg of truffles (make it the plural for appearance’s sake), at a cost of probably less than £200 and email a press release to a few news desks. Suddenly the idea of Morrisons wanting to go upmarket seems a bit less likely?

As ever there is another perspective. The competition nationally amongst supermarkets does not make things easy for them. Tesco have traditionally been the standard cheap supermarket, and remain so. They probably do some nicer things and they are very consistent, but they are not going for higher-end shoppers and probably never will. There are food halls, Harrods and Selfridges, who do the highest end. One below this is John Lewis food halls and Waitrose, the two of which are owned by the same company. Their delivery arm is separate, but it is the same stuff.  In between Waitrose and Tesco there is a ‘lower middle class’ gap that is filled in by Sainsbury’s. At the very cheapest end there are Aldi and Lidl. Apparently these, both German in origin, are not micro-budget supermarkets everywhere; they are better-than average quality in parts of Germany. Either way, we appear to have quite a well-defined order with food halls at the most expensive end, then Waitrose, Sainsbury’s, Tesco and finally Aldi/Lidl being the cheapest. Thus, there is not a lot in the way of space to slide into for a supermarket like Morrisons, that is traditionally regional, but upon buying Safeway (as was) went national.

Plenty of people try to equate class with choice of supermarket. This seems like a weak structure to apply if you ask me, given how much else there is to look at. When I last checked, apparently £1 in every £8 that is spent in Britain, is spent in Tesco. I do not think that is a good thing, and I cannot get the ingredients I want, so I do not shop there. Food halls are too far away and I cannot be faffed with their expense when I am experimenting with a recipe anyway. And Sainsbury’s and Waitrose do me very well. I have never been into a Morrisons, and PR stunts like this one do not encourage me to. Of course, I can get what I want elsewhere and know a man who can do me a good price on black Italian truffles should I ever need them, which means I need not get the train to Kirkstall. But if I were running Morrisons and wanted the firm to stay competitive I am not sure what I would come up with to get them heard of by the widest possible market. If you were running Morrisons, what would you do?

This article was published in The Felix on 8th August 2011, and can be found in the on-line version here.

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