It takes 21 litres of water to produce a small chocolate bar. How water-wise is your diet?



A small chocolate bar takes 21 litres of water to produce.
Byline: CAROLINE BLUMBERG/ EPA

Brad Ridoutt, CSIRO; Gilly Hendrie, CSIRO, and Kimberley Anastasiou, CSIRO

Our diets can have a big environmental impact. The greenhouse gas emissions involved in producing and transporting various foods has been well researched, but have you ever thought about the water-scarcity impacts of producing your favourite foods? The answers may surprise you.

In research recently published in the journal Nutrients, we looked at the water scarcity footprints of the diets of 9,341 adult Australians, involving more than 5,000 foods. We measured both the amount of water used to produce a food, and whether water was scarce or abundant at the location it was drawn from.

The food system accounts for around 70% of global freshwater use. This means a concerted effort to minimise the water used to produce our food – while ensuring our diets remained healthy – would have a big impact in Australia, the driest inhabited continent on Earth.

Biscuits, beer or beef: which takes the most water to produce?

We found the average Australian’s diet had a water-scarcity footprint of 362 litres per day. It was slightly lower for women and lower for adults over 71 years of age.

A water-scarcity footprint consists of two elements: the litres of water used, multiplied by a weighting depending on whether water scarcity at the source is higher or lower than the global average.

Foods with some of the highest water-scarcity footprints were almonds (3,448 litres/kg), dried apricots (3,363 litres/kg) and breakfast cereal made from puffed rice (1,464 litres/kg).

In contrast, foods with some of the smallest water-scarcity footprint included wholemeal bread (11.3 litres/kg), oats (23.4 litres/kg), and soaked chickpeas (5.9 litres/kg).




Read more:
What’s made of legumes but sizzles on the barbie like beef? Australia’s new high-tech meat alternative


It may surprise you that of the 9,000 diets studied, 25% of the water scarcity footprint came from discretionary foods and beverages such as cakes, biscuits, sugar-sweetened drinks and alcohol. They included a glass of wine (41 litres), a single serve of potato crisps (23 litres), and a small bar of milk chocolate (21 litres).

These foods don’t only add to our waistlines, but also our water-scarcity footprint. Previous studies have also shown these foods contribute around 30% of dietary greenhouse gas emissions in Australia.

Sheep drink from a dried-up water storage canal between Pooncarie and Menindee in western NSW. Water shortages along the Murray Darling Basin have devastated ecosystems and communities.
Dean Lewins/AAP

The second highest food group in terms of contributing to water-scarcity was fruit, at 19%. This includes whole fruit and fresh (not sugar-sweetened) juices. It should be remembered that fruit is an essential part of a healthy diet, and generally Australians need to consume more fruit to meet recommendations.

Dairy products and alternatives (including non-dairy beverages made from soy, rice and nuts) came in third and bread and cereals ranked fourth.

The consumption of red meat – beef and lamb – contributed only 3.7% of the total dietary water-scarcity footprint. These results suggest that eating fresh meat is less important to water scarcity than most other food
groups, even cereals.

How to reduce water use in your diet

Not surprisingly, cutting out discretionary foods would be number one priority if you wanted to lower the water footprint of the food you eat, as well as the greenhouse gas emissions of production.

Over-consumption of discretionary foods is also closely linked to weight gain and obesity. Eating a variety of healthy foods, according to energy needs, is a helpful motto.

Aside from this, it is difficult to give recommendations that are relevant to consumers. We found that the variation in water-scarcity footprint of different foods within a food group was very high compared to the variation between food groups.




Read more:
Curious Kids: why can’t we just build a pipe to move water to areas in drought?


For example, a medium sized apple was found to contribute a water-scarcity footprint of three litres compared with more than 100 litres for a 250 ml glass of fresh orange juice. This reflects the relative use of irrigation water and the local water scarcity where these crops are grown. It also takes more fruit to produce juice than when fruit is consumed whole.

Two slices of wholegrain bread had a much lower water-scarcity footprint than a
cup of cooked rice (0.9 litres compared with 124 litres). Of the main protein sources, lamb had the lowest water-scarcity footprint per serve (5.5 litres). Lambs are rarely raised on irrigated pastures and when crops are used for feeding, these are similarly rarely irrigated.

Consumers generally lack the information they would need to choose core foods with a lower water-scarcity footprint. Added to this, diversity is an important principle of good nutrition and dissuading consumption of particular core foods could have adverse consequences for health.

Workers process punnets of strawberries at a Queensland strawberry farm.
Dan Peled/AAP

Perhaps the best opportunities to reduce water scarcity impacts in the Australian food system lie in food production. There is often very large variation between producers in water scarcity footprint of the same farm commodity.

For example, a study of the water scarcity footprint of tomatoes grown for the Sydney market reported results ranging from 5.0 to 52.8 litres per kg. Variation in the water-scarcity footprint of milk produced in Victoria was reported to range from 0.7 to 262 litres. This mainly reflects differences in farming methods, with variation in the use of irrigation and also the local water scarcity level.

Water-scarcity footprint reductions could best be achieved through technological change, product reformulation and procurement strategies in agriculture and food industries.

Not all water is equal

This is the first study of its kind to report the water-scarcity footprint for a large number of individual self-selected diets.

This was no small task, given that 5,645 individual foods were identified. Many were processed foods which needed to be separated into their component ingredients.




Read more:
Climate explained: what each of us can do to reduce our carbon footprint


It’s hard to say how these results compare to other countries as the same analysis has not been done elsewhere. The study did show a large variation in water-scarcity footprints within Australian diets, reflecting the diversity of our eating habits.

Water scarcity is just one important environmental aspects of food production and consumption. While we don’t suggest that dietary guidelines be amended based on water scarcity footprints, we hope this research will support more sustainable production and consumption of food.

The author originally disclosed that he undertakes research for Meat and Livestock Australia. His disclosure has been updated to specify that the above research is among the projects to which the MLA has contributed funding.The Conversation

Brad Ridoutt, Principal Research Scientist, CSIRO Agriculture, CSIRO; Gilly Hendrie, Research scientist, CSIRO, and Kimberley Anastasiou, Research Dietitian, CSIRO

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Sustainable shopping: save the world, one chocolate at a time


Robert Edis, Australian Centre for International Agricultural Research; Kanika Singh, University of Sydney, and Richard Markham, Australian Centre for International Agricultural Research

Shopping can be confusing at the best of times, and trying to find environmentally friendly options makes it even more difficult. Our Sustainable Shopping series asks experts to provide easy eco-friendly guides to purchases big and small. Send us your suggestions for future articles here.


Cocoa is probably the most sustainable of all internationally traded commodities, so there are several “feelgood” reasons for eating the chocolate made from it this Easter – at least when the cocoa is grown by smallholder producers and traded by processors that are committed to equitable sharing of profits.

Here are some ways to tell if you are onto a good thing.

Environmental impact

As a wild species, cocoa (Theobroma cacao) originates from the rainforest of the Amazon basin and the foothills of the Andes. In nature, it grows as an “understorey” species, shaded by the rainforest canopy. Much of the world’s cocoa crop is similarly grown in the shade of taller trees in mixed plantings.

Unlike many plantation crops, like rubber and oil palm, cocoa can be grown with a diverse mixture of other plants. Of course, not all growers produce this way, so if preserving biodiversity is a priority for you, look for Rainforest Alliance certification.

Healthy cocoa, grown in an agroforestry system with minimal chemical inputs, in Fiji. The cocoa beans are in the yellow pods.
Richard Markham

Cocoa needs a lot of water to survive, so large irrigated plantations have a high water footprint. On the other hand, almost all smallholder cocoa is grown without irrigation in high-rainfall areas, so the water used in production of the cocoa is close to zero (apart from a small amount of water used in processing).

Another environmental aspect is the use of fertilisers and pesticides. When cocoa pods are harvested they take a lot of nutrients with them, out of the ecosystem. On average, a kilogram of dry cocoa contains 36 grams of nitrogen, 6g of phosphorus, 72g of potassium, 7g of calcium, and 6g of magnesium.

This means maintaining soil condition is critical. This can be achieved with careful application of fertiliser, though this rarely occurs and soil depletion has become a major problem prompting aid groups to encourage more fertiliser use!.

However, research in Sulawesi, supported by the Australian Centre for International Agricultural Research and chocolate giant Mars Inc, has shown that using a judicious combination of nitrogen-fixing shade trees and compost (ideally produced with the help of goats) can maintain soil fertility – and even reclaim depleted speargrass savanna – for cocoa production.

Trials by Indonesian and Australian researchers in Sulawesi suggested that a combination of compost and inorganic fertiliser gave the best results.
Richard Markham
Research trials on sustainable cocoa production at the ‘Mars Academy’ research station in Sulawesi, Indonesia.
Richard Markham

Finding good chocolate

The good news is that there are plenty of chocolate producers who avoid all of these problems. There are two ways to find it: look for certifications, or seek out small operations in our region.

Fairtrade certification means that smallholder producers in developing countries are getting a fair share of the price you pay.

Rainforest Alliance certification, meanwhile, ensures that rainforest hasn’t been cleared to make way for unsustainable plantations.

If you’re concerned about fertiliser and pesticide use, UTZ (who have recently merged with the Rainforest Alliance) has built sustainable productivity into their certification systems.

All of these certification schemes are largely available to multinational companies. Some of the biggest chocolate companies in the world, including Mars, Ferrero, Hershey and Nestlé, have committed to sourcing 100% certified cocoa, so it’s possible to buy sustainable cocoa without even realising it.

On the other end of the scale are smallholdings, which are likely to lack these kinds of certifications. That doesn’t always mean they are bad for the environment, or that the growers aren’t getting a fair price. It may simply be that the expense of formal certification is not worth it for many small operations.

Much of this chocolate is organic more or less by default, as many smallholders, especially in the Pacific region, simply do not use agrochemicals. It’s also more likely to be grown in heavily rainforested areas, with almost zero water footprint.

In their search for high quality and unique flavours, several Australian boutique chocolate makers have started to source their beans directly from cacao growers.

For instance, Bahen & Co. in Margaret River, Western Australia, purchases beans directly from communities on Vanuatu’s Malekula island, while Jasper & Myrtle in Canberra buys beans from growers on PNG’s previously troubled island of Bougainville.

These programs mean that these growers have been able to taste chocolate from their own beans for the first time, and thus understand how their own processing of the beans – through fermentation and drying – affects the quality of the final product.

Australian chocolate maker Mark Bahen evaluates samples of beans from individual growers in Vanuatu.
Conor Ashleigh for ACIAR

Even more value can remain with the local growers and their communities if the chocolate itself is manufactured in-country. Visitors passing through duty free shops as they leave PNG may have picked up Queen Emma chocolate, made by Paradise Foods in Port Moresby, while those leaving Nadi may have bought Fijiana chocolate made by local company Adi’s Chocolate.

Australian shoppers will soon be able to buy Aelan chocolate – single-origin bars from four different islands of Vanuatu, made in Port Vila by ACTIV, a Victorian NGO founded and operated on fair-trade principles.

At the furthest end of the fine-flavour chocolate trend are chocolate bars with no artificial additives of any kind. A favourite recipe among discerning chocolate-tasters is simply to mix 80% cocoa “nibs” (coarsely ground beans) with 20% sugar and “conch” it gently until smooth and delicious.

Drying cocoa beans in the sun helps to develop the best flavour (in this case Kerevat, PNG)
Yan Dicbalis

What about food miles and the carbon footprint?

The typical cocoa bean from the Asia-Pacific region is bought by the local representative of a global commodity trader. It is shipped to Singapore, or directly to Indonesia, which has the capacity to grind some 600,000 tonnes of cocoa each year. The ground or whole beans then travel onward to Europe.

Belgium has a well-established reputation as the world’s preferred provider of “cocoa liquor”, and some of this is shipped back to Australia as the raw material for local chocolate manufacture – now with a sizeable carbon footprint.

Other beans will be shipped to France, Italy, Switzerland (or will remain in Belgium) for manufacture into delicious chocolates, and some of these too will be shipped back to our region for retail sale. If fossil fuels and global warming are among your concerns, consider seeking a chocolate product that was grown and processed nearby.

The big players are Cote d’Ivoire, Ghana and Indonesia, with small amounts of smallholder-dominated production in the Pacific.
ICCO, 2017. Quarterly Bulletin of Cocoa Statistics. Vol. XLIII, No. 3. Cocoa year 2016/17. International Cocoa Organization, London

The ConversationIn sum, with a bit of attention to the back story, you can enjoy a whole range of delicious new chocolate experiences this Easter – and feel that you are contributing at the same time to the equitable and sustainable development of the planet.

Robert Edis, Soil Scientist, Australian Centre for International Agricultural Research; Kanika Singh, Research Fellow, University of Sydney, and Richard Markham, Research Program Manager for Horticulture, Australian Centre for International Agricultural Research

This article was originally published on The Conversation. Read the original article.