Sweet And Sour

The original question that I set out to investigate about sugar was to do with its environmental impact, specifically the claim made by the cake maker Geraldene Holt on BBC Radio 4, that beet sugar was worse for the environment than cane sugar.

“Lovely natural Muscovado Sugar, this is healthy of course.” …”Well, I think it’s healthier for the environment; it’s not sugar beet.”

Since then, I have spent hours reading about sugar.  I have looked at its taxonomy, its cooking properties and above all the social and environmnetal effects.  Much of what I have discovered is truly shocking.  In ecology terms, sugar has probably done more damage to our environment than any other crop.  Habitat destruction, abstraction of water, intensive application of agrochemicals, discharge and run-off of polluted effluent and air pollution caused by the sugar industry continue to threaten many of the most precious ecosystems in the world.  Much of the damage is historical but sugar production is still growing and the environmental damage is getting worse.  However sugar beet and sugar cane are about as different from one another as two arable crops can be.  They grow in different parts of the world, present entirely different biological profiles and share almost nothing in common except a high sucrose content.  So let’s consider them separately.

Sugar Beet

Sugar beet is grown in temperate regions of the Northern Hemisphere.  The biggest beet producers are The EU, USA, Russia, Ukraine and Turkey, with smaller quantities produced in Japan, Canada, China, and sporadically around the Middle East and central Asia.

I am quite familiar with sugar beet production.  There’s a field of beet growing no more than a quarter mile from my front door right now. I have watched it growing from the day it was planted and no doubt I’ll be around to see it carted off in trucks to the refinery 43 miles away in Bury St Edmunds.  Now I recognize that all economic activity has an environmental impact, and farming has a bigger impact than most, but it wasn’t clear to me that sugar beet, which looks so benign, was significantly worse than any other arable crop grown hereabouts.  What is it that makes sugar beet so ecologically damaging?  The clue came from another BBC broadcast where I heard Prof. Dennis Murphy of The University of Glamorgan make the following statement, “We grow sugar beet here [UK] which doesn’t make any sense at all environmentally.  We should be importing it from places where sugar cane grows which has a lower carbon footprint.”

OK so that’s the problem, the Green House Gas (GHG) emissions related to making sugar from beet.  So let’s examine that in more detail.  In 2008 British Sugar, which is the UK’s sole sugar beet producer, became the first sugar industry in the world to have its carbon footprint certified.  In partnership with the Carbon Trust it was independently benchmarked using the BSI’s PAS 2050 standard. They calculated that 1kg sugar produces 0.5kg of CO₂ equivalent (CO₂eq).  Almost half, 48.7%, is produced on the farm and includes the use of fertilizers, water, diesel etc;  27.4%, comes from the factory; while distribution, 8.8%, packaging, 7.9%, and transportation of raw materials, 7.2%, account for the rest. That does sound like quite a lot.  For every bag of sugar you buy you are also purchasing half a bag of GHGs.  However we need to put that in context.

The Carbon Trust estimates that the UK has a carbon footprint of 650 million tonnes of greenhouse gas. This means each person in the UK has an estimated footprint of about 11 tonnes a year.  According to a report by WWF and the Food Climate Research Network (FCRN), food is responsible for 30% of the UK’s total carbon footprint, or 217 million tonnes.  But where does sugar beet stand in that reckoning?  Well compared with other foods it seems it may not be too bad. 1Kg homegrown potatoes produces about 0.5Kg CO₂eq, very similar to sugar beet.  That ratio turns out to be more or less true for most other native fruits and vegetables.  And when you look at some of the big GHG producers it is downright green.

A single cheeseburger produces about 5.18Kg CO₂eq (Source)
A litre of milk produces 1.97Kg CO₂eq (Source)
1Kg sheep meat produces 16.8Kg CO₂eq (Source)
1 Kg tomatoes grown under glass produce 9Kg CO₂eq (Source)

Furthermore the sugar industry has done more than most in recent years to improve its performance.  The industry’s own Sustainability Report, sponsored jointly by British Sugar and the National Farmers’ Union (NFU) makes a number of exceptional claims:

-          Yields per acre have risen by 60% in the past 30 years

-          Energy consumption per tonne is down by 25% since 1990

-          Since 1982 pesticide application has been cut by 60%, phosphates by 70% and nitrogen by 40%

-          Waste to landfill reduced by 50% since 2003

-          They also produce a range of byproducts from animal feed to electricity

All of these serve to reduce the carbon footprint, and nationally the industry is targeting a further reduction of 10% by 2020.  So overall it seems that sugar beet is no worse than other food products, but perhaps sugar cane provides a much greener alternative.  We need to do a comparison.

Sugar Cane

Fortunately Tate & Lyle, the UK’s biggest cane sugar producer, followed British Sugar’s lead and had its carbon footprint measured by the Carbon Trust in 2009, so it is possible to compare like for like.  And the result is…Tate & Lyle’s cane sugar has a carbon footprint of 380g CO₂eq per 1Kg sugar, only 76% of the GHG emissions from beet sugar.

This provides an interesting reminder that food-miles alone are not a sufficient measure of sustainability when making purchasing decisions.  The carbon cost of sea transportation for sugar and sugar products forms a relatively small part of the overall footprint and therefore does not outweigh the lower cost of production on the plantation.

Unfortunately that’s not the end of the argument.  Sugar cane is grown in over 100 countries with wide differences in technology, education and geography and these greatly affect the environmental impact.  Also GHG emissions are not the only concern.

Among the most advanced sugar cane industries in the world is Australia’s.  There, researches from the University of Queensland led by Marguerite Renouf and Malcolm Wegener have carried out a whole Life Cycle Assessment (LCA) of sugar cane production in Australia and compared it with sugar beet in the UK and Corn Syrup from USA. 

They found wide variations even within Queensland.  However looking at the state average their overall conclusion was favourable to sugar cane when considering solely the carbon footprints of these three crops.  On the other hand, when the wider environmental picture was assessed the findings were less favourable. To quote the report “Cane sugar is shown to have distinct advantages in relation to energy input, greenhouse gas emissions, and land utilization, but does not rate as well in relation to other impacts assessed (eutrophication and water use)". 

They are not kidding.  Another WWF report from 2004 entitled Sugar and The Environment, claimed that sugar may be responsible for more biodiversity loss than any other crop, due to its destruction of habitat to make way for plantations, its intensive use of water for irrigation, its heavy use of agricultural chemicals, and the polluted wastewater that is routinely discharged in the sugar production process. 

The list of natural environments cited by the report, which have been severely damaged by sugar production, reads like a list of the world’s most beautiful, important and sensitive natural habitats. 

The Great Barrier Reef, off the coast of Queensland, “suffers from large quantities of effluents, pesticides and sediment from sugar farms, and the reef itself is threatened by the clearing of land, which has destroyed the wetlands that are an integral part of the reef’s ecology.” 

The Everglades in Florida are, “seriously compromised after decades of sugar cane farming. Tens of thousands of acres of the Everglades have been converted from teeming sub-tropical forest to lifeless marshland due to excessive fertilizer run-off and drainage for irrigation.”

In Pakistan’s Indus Delta, a globally significant mangrove system,  “Of the 260,000 hectares of mangrove forest recorded in 1997, only an estimated 65 percent remains and is dominated by just one salt-tolerant species.” While the indigenous “Blind River Dolphin (Platanista minor), found throughout the Indus and its tributaries100 years ago, now exists in six totally isolated sub-populations.”

Soil depletion, salination and land clearance for planting cane continue to take their toll in Brazil, Papua New Guinea, Cuba, South Africa, Puerto Rico and many other places. 

Of course, just like beet producers, the cane industry, is also doing its best to become more efficient and more environmentally responsible.  The industry body Bonsucro describes itself as “A global multi-stakeholder non-profit initiative dedicated to reducing the environmental and social impacts of sugar cane production. It aims to achieve this with a Standard that measures these impacts accurately, and with the development of a system to certify that sustainable practices are being adhered to.”

The WWF report itself provides a long list of proposed improvements to land management practices, which can provide economic benefits for farmers and mill owners while addressing environmental degradation.  These include better use of water, more responsible use of additives and exploitation of by products. It seems there is a lot that can be done to make sugar much, much greener.

More than 145 million tonnes of sugar is produced per year in about 120 countries and annual consumption is expanding each year by about two million tonnes. But interestingly it is not the consumer’s sweet tooth that is driving the market so much as his car.  The high energy content in both sugar cane and beet make them natural crops for the burgeoning biofuels industry.  For instance Brazil today has over 12million cars and trucks that run on neat ethanol produced from cane sugar, and by Brazilian law gasoline must now be mixed with 25% ethanol.  In certain US states also gasoline is mandated to be blended with 10% ethanol.  Unlike fossil fuels, biofuels are renewable, politically secure and offer a lower level of GHG emissions.  Although they do occupy huge areas of agricultural land, and contribute both directly and indirectly to deforestation or the use of other virgin land such as Brasil's cerado.

Interestingly, a report on the Bonsucro site by Dr. Peter Rein, Professor Emeritus of Louisiana State University, claims that, “pressure for sustainable production [of cane sugar] has come largely from the importers of ethanol from sugarcane. This has focused attention on sustainable production in the sugar industry in general.”  Specifically he mentions the EU’s Renewable Energy Directive RED as a driver of improved standards.

In other words it is the biofuels sector which is forcing sugar producers to clean up their acts not sugar retailers or consumers.  That is all well and good but maybe next week we will consider how to feed 9 billion people, when so much of the earth’s productive land is given over to producing biofuels.

All of which seems a very long way away from Geraldene Holt and her carrot cake.  So to answer my original point from all that time ago, go ahead and use your ‘lovely, natural muscovado sugar’.  It’s not a healthy option, but I bet it will taste delicious. The 10oz you put in the cake will save 36g of CO₂eq compared with beet sugar, and in the big picture it won’t matter a fig.  What is more important is the 5Kg of Co2eq generated by driving an average (1800cc) petrol car for 25Km to the supermarket and back.  So perhaps the best thing is to put the sugar in your car after all.