Something about sugar (free)

Blenheim Flower Show

The Blenheim Flower Show

Last month I went to the Blenheim Flower Show. I hadn’t been before, and I wasn’t quite sure what to expect. In my head I was imagining rows and rows of flowers with a sort of maze-like path through them. I have no idea why, possibly I’ve been doing too much Wizard of Oz (this is not a euphemism).

Perhaps not surprisingly it wasn’t like that at all. In fact the flowers were confined to a couple of easily-avoidable tents, leaving me to wander around stalls selling everything from jewellery to space-saving furniture, chat to the jolly interesting chaps giving a bee-keeping demonstration and scrounge free samples from the food tent.

And it was in the food tent that I came across the Raw Chocolate Pie stall. Sounds good doesn’t it? They’ve combined some very appealing words there. Anyway, the ladies on the stall were very nice and gave me some pieces to taste, and it was indeed scrummy, and sweet. I mention this because in huge letters across the top of the stall were the words “sugar free”. Hm, I thought. They had already told me that the ‘pies’ (actually more like chocolatey lumps) were made with raw cacao beans. Now, I’m a fan of dark chocolate and I’ve tasted 90% cocoa chocolate. It’s bitter. Bitter with a capital bit. It also has a sort of powdery texture due to the low fat content, and this had neither quality.

“So,” I said conversationally, “what’s it sweetened with?”

“Agave nectar,” came the reply.

thefoodofthegodsAt this point I’d heard of agave nectar but I wasn’t really sure what it actually was, so I simply nodded and bought a bar of nut pie. I intended to bring it home and investigate it properly, but it was hot and it got a bit melty, so I was forced to eat it at lunchtime. I took a picture of the wrapper though.

See how it says “sugar free” right there at the top? They are big on this claim. It says sugar free all over the Living Food raw chocolate pie website too.

What would you imagine that means?

It’s a pertinent question. Sugar is one of those words, like ‘salt‘ and ‘alcohol‘, which has a subtly different meaning in chemistry than it does in everyday speech. For chemists these are groups of compounds, but if you read “add pinch of salt” in a recipe book you don’t wonder whether to add sodium chloride or the copper sulfate from your child’s chemistry set. Likewise, if a bottle of wine claims to be 14% alcohol you don’t ponder whether it’s safe to drink or whether you should save it for paint stripper. (Unless, that is, it’s very cheap wine indeed.)

No, in everyday speech we know that salt means sodium chloride, alcohol means ethanol and sugar means, er… sugar means…

Sucrose

Sucrose

This is where it gets a bit sticky. Because there’s more than one sugar that we eat on a regular basis. The white, or sometimes brown, stuff that people bake with and plop into their hot beverages is mainly sucrose. It’s also called ‘table sugar’, or sometimes ‘cane sugar’ or ‘beet sugar’, because those are the plants from which it’s extracted.

Raw chocolate pies haven’t been made with cane/beet sugar, so they might be able to truthfully claim to be sucrose-free. But sugar-free? We-ell…

180px-Glucose_chain_structure

Glucose

The other two sugars that we’re probably most familiar with are glucose, which is the fuel our cells use for energy during respiration, and fructose, which is found in plants and which, like glucose, can be absorbed directly into the bloodstream.

200px-Skeletal_Structure_of_D-Fructose

Fructose

So fructose is found in plants. In fact, fructose is often found in plants chemically bonded to glucose. To make…. sucrose.

So in short:
glucose + fructose = sucrose

And they’re all sugars, and we eat them all on a fairly regular basis. Our bodies break up sucrose into units of glucose and fructose during digestion, and it’s fair to say that none of them are particularly healthy if consumed in large quantities. They’re calorific, bad for your teeth, nutrient-free (other than as an energy source), and regularly eating large quantities of sugar (of any kind) puts you at a greater risk of type II diabetes.

So what’s in agave nectar? Well it comes from a plant, the agave plant, so if you’ve been paying attention that should give you a clue. Yep, it’s packed full of fructose. Which is a sugar. In fact, there are a lot of health concerns around fructose. You may have heard of high fructose corn syrup, or HFCS. This stuff is controversial, with claims that it contributes to obesity, cardiovascular disease, diabetes and non-alcoholic fatty liver disease. Other groups claim these links are unproven, and it’s no worse than any other type of sugar. These groups are mainly people that make and sell high fructose corn syrup, so draw your own conclusions.

Back to agave nectar or, more accurately, syrup. It actually has considerably more fructose than high fructose corn syrup. So bearing all that in mind, is it a healthy alternative? Er, almost certainly not.

Is it correct to call something that’s sweetened with agave ‘sugar free’?

I had a little poke around the Food Standards website. It was something of a slog, but as far as I can work out, the word ‘sugar’ in an ingredients list specifically refers to sucrose. So, you don’t have to list ‘sugar’ in the ingredients list if sucrose isn’t specifically used as an ingredient. But what about the term ‘sugar-free’?

I struggled to find a clear definition of this term on the FSA website, which was a bit annoying (see update below). The best source I can come up with is The Sugar Association, which I’m fairly sure is an American site and so the information quoted wouldn’t apply to a British producer. Still, it’s the best I’ve got, and I’d put money on the rules being similar if not quite identical. This is what they say:

‘“Sugar Free”: Less than 0.5 g sugars per reference amount and per labeled serving (or for meals and main dishes, less than 0.5 g per labeled serving). No ingredient that is a sugar or generally understood to contain sugars except as noted below(*)’ (sic)

The “as noted below” refers to sugar alcohols. These are things like xylitol, mannitol and sorbitol. They often turn up in things like chewing gum. Fructose, at the risk of stating the obvious, is not a sugar alcohol.

There was no percentage composition on the raw chocolate pie wrapper, but just from the taste I’m pretty certain it had more than 0.5 g of sugars (i.e. fructose) per serving. Nothing is that sweet without sugars, unless it also contains artificial sweeteners (which aren’t listed as an ingredient).

I did find this on the Food Standards website:

“To sell food and drink products, the label must be: […] not misleading”

Sugar-free Coke?

Sugar-free Coke?

Is calling something sweetened with a high-fructose syrup (because that’s what agave ‘nectar’ is) misleading? I’m afraid to say that, although I did very much enjoy my nut pie snack, I think it is. By the logic that seems to be being applied here, Coca Cola could use high fructose corn syrup as an sweetener and label their red non-diet bottles and cans as sugar-free, which would be patently ridiculous.

It’s a shame really, because Living Food have a nice product. They just need to get their labelling sorted out.

—-

Update 4th August 2014
After I wrote this I continued my quest to find a proper definition of “sugar-free”. I tried the Food Standards Agency, who sent me to Defra, who ignored me. So I went back to the FSA, who eventually sent me this link. It’s a very interesting document, clarifying and giving examples of how EU Regulation No. 1924/2006, which is all about nutrition and health claims on food, should be applied. On page 70 it says:

‘”The Regulation does […] define any product with no more than 0.5g of sugar per 100ml or per 100g as “sugar free”’

And so conversely, anything with more than 0.5 g of sugar per 100 g as NOT sugar-free. (The official definitions of sugar-free, low-sugar and no added sugar can all be found in the Annex, on page 14, of EU Regulation No. 1924/2006). What still wasn’t entirely clear was exactly what’s meant by ‘sugar’. But now I had somewhere to start. Rooting through EU Regulation No. 1924/2006 I found that it referred to Directive 90/496/EEC for definitions. And there, finally, I got my answer, in Article 1, page 4:

“‘sugars’ means all monosaccharides and disaccharides present in food, but excludes polyols”

Voilà! Fructose is a monosaccharide, and therefore if your product has more than 0.5 g of fructose per 100 g, then it cannot accurately be labelled sugar-free.

I can’t prove this is the case for the Raw Chocolate Pies, since I my testing involves tasting two samples. But if it looks like a duck, and quacks like a duck, it’s probably a very sugary duck.

The question of ‘no added sugar’ may be somewhat irrelevant, since they’re not making this claim, but I think it’s illuminating. If agave syrup has been added then “no added sugar” can’t even be used, since (from regulation (EC) No. 1924/2006):

“A claim stating that sugars have not been added to a food, and any claim likely to have the same meaning for the consumer, may only be made where the product does not contain any added mono- or disaccharides or any other food used for its sweetening properties.”

So that’s the end of the journey, really. You can only call something sugar-free if there’s no sugar in it, and that includes fructose (‘fruit sugar’), glucose and sucrose (‘table’ sugar). Foods sweetened with agave, which contains fructose, aren’t sugar-free, unless they have only the tiniest amount – less than 0.5 g per 100 g – added.

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The chemistry of chocolate

A lot of people believe there’s a deep religious significance to the holiday we’re enjoying right now.  Others argue it’s older than that: an ancient spring festival, celebrating the spring equinox, fertility and new growth.

funny-chocolate-Periodic-Table-chemistryBut every child knows what Easter is really all about.  Yes.  Chocolate.  Yummy, delicious chocolate.

So with that in mind, let’s talk a little about the chemistry of chocolate.  For it is very interesting stuff.  What’s in the lovely, creamy, sweet brown stuff?  And how do they get it to melt so perfectly in your mouth?  And does it really give you a happy high?

How do they get chocolate to melt so perfectly at body temperature?  There is more to this than you might imagine.  First of all you have to know something about crystals.  Most people, upon hearing the word crystals, think about clear, shiny things twinkling from from Katie Price’s latest wedding dress.  But in fact lots of substances form crystals, because a crystal is just a piece of any solid material that has regular shapes arranged symmetrically.  Crystals don’t have to be transparent.  Metals are crystalline.  Pure iodine forms rather pretty grey-silver crystals.  And, crucially, fat also crystallises.

In fact the fat in chocolate, cocoa butter, can crystallise in many different forms.  Only one of these is the lovely, hard, shiny one that is so nice and snappy at room temperature.  If you’ve ever cooked with chocolate, or indeed just left it in the car on a hot day by accident, you probably know that if you melt it and then just let it solidify again the result is dull-looking and crumbly.  Getting the right form of chocolate crystals to form is called tempering, and it’s a complicated business.  First the chocolate has to be melted at a high enough temperature to melt all the crystals.  Then it needs to be cooled to just the right temperature for the best crystals to grow, then agitated, then warmed up a tiny bit (but not too much), then cooled again.  There are other methods, but this is the one that’s used in the big chocolate factories.  Just ask the Oompa Loompas.

This ideal fat crystal form not only looks good and snaps nicely, it also melts at 34 oC.  Normal body temperature is actually around 36 oC, with the oft-quoted 37 oC actually being a tad on the high side.  Skin temperature, on the other hand (geddit?), is somewhere between 32-35 oC depending on how warm the environment is.  This means that chocolate will just about stay solid in your fingers if you don’t hold it too long, but put it in your mouth and the temperature is just right to melt it perfectly, releasing delicious sweetness, creamy fats and other chemicals that stimulate your tastebuds and give chocolate its flavour (craving your easter eggs yet?)

What about the other question: does chocolate really give you a ‘happy high’?  Well, it turns out there’s a whole cocktail of naturally-occurring bioactive chemicals (some people see ‘natural chemicals’ as a bit of an oxymoron and that’s ironic in a way, since the very brain that learned big words like oxymoron is actually stuffed full of natural chemicals that make it work) in chocolate.  Firstly, caffeine, otherwise known its less tongue-tripping name of 1,3,7-trimethylxanthine, but we’ll stick to caffeine.

We’re all familiar with caffeine from tea and coffee, and that drink that’s falsely advertised as giving you wings, but its presence in chocolate is sometimes forgotten.  It is of course a stimulant, exciting the central nervous system (it’s very excitable), boosting heart rate and contracting muscles.  It also acts on receptors in the brain and causes them to release pleasure-producing chemicals.  There isn’t a lot in chocolate though: it varies by type but even in the darkest of dark chocolate, there’s generally less caffeine than you’d get from even a single cup of tea.  Milk chocolate has even less and white chocolate has none at all.

But there’s more of another chemical, also a stimulant: theobromine.  This is interesting stuff.  It’s a heart stimulant and, like caffeine, a diuretic (it makes you wee).  More recently it’s use as a potential treatment for cancer tumours has been investigated.  There is roughly eight times more theobromine in chocolate than caffeine, but we metabolise it quickly so it doesn’t hang around in our bodies for long.  It’s less safe for animals: as any responsible dog owner will tell you, chocolate is very bad for dogs.  This is mostly due to the theobromine (the caffeine isn’t great either, but there’s not so much of that).  If your pooch gets into your Easter eggs, they could suffer nausea and vomiting, diarrhea, muscle tremors and, potentially, heart failure.  So keep your eggs out of reach.

It’s not just stimulants.  Chocolate also contains fatty acids called cannabinoids.  Guess what they’re similar to?  The clue is in the name… yes, their cousin is called tetrahydrocannabinol, and it’s found in the cannabis plant.  When cannabinoids hit the brain they make you feel relaxed and intoxicated.  And that’s not all, chocolate also contains phenethylamine, sometimes dubbed ‘the love drug’ because levels increase in the body when you’re feeling romantic.  Although there isn’t much and it’s metabolised too quickly to  have a significant effect.

So with this delicious swirly mixture of stimulants and suppressants, surely chocolate ought to be on some sort of controlled drug list?  Well, no.  All of these chemicals are present in relatively small amounts, and have a limited effect on the body (human bodies anyway).  People who suffer chocolate cravings aren’t satisfied by just swallowing capsules that contain the relevant chemical compounds, but eating white chocolate – which contains no cocoa solids and therefore none of the psychoactive ingredients – does the trick.  This suggests that the real reason we like chocolate is simply the same reason we like cream cakes: lots of sugar and fat – yummy!

So now you’ve stuffed your brain full of sciencey-stuff, go ahead and stuff your mouth with lots of yummy chocolate.  Happy Easter!

P.S. have you noticed that it’s kem-is-try but cho-ko-late?  This alliteration spoiling bit of linguistics is because the word chemistry derives from the word alchemy, which (probably, people argue over these things) comes from the ancient Egyptian name for Egypt – khem or khame, or khmi.  Hence al-khmi, ‘the Egyptian art’.