food, climate change and waste: why worry? tara garnett food climate research network 11 july 2007
TRANSCRIPT
Food, climate change and waste:Why worry?
Tara Garnett
Food Climate Research Network11 July 2007
Question
• Why is food waste a problem in the context of food related greenhouse gas emissions?
Two key reasons
• Decomposing food generates methane (small problem)
• Wasted food represents a waste of all the emissions generated during the course of growing, processing, storing, transporting, retailing and cooking the food. (BIG PROBLEM)
This presentation
• Food and its GHG contribution – how much?– By life cycle stage– By food type
• The relationship between GHG intensive foods and food waste
• The problem of the fridge!• Climate change impacts on food (and waste)• What does a less GHG intensive way of eating
look like?
First – a quick lesson in terminology
• GHGs = greenhouse gas emissions
• CO2 the main GHG but…
• …others also important especially for food– Methane: 21 x more potent than CO2
– Nitrous oxide: 310 x more potent than CO2
– Refrigerant gases: thousand of times more potent than CO2
What part does food play?
Need to consider emissions at all stages in the food chain:• Agriculture• Manufacturing • Refrigeration• Transport• Packaging • Retail• Home • Waste They ALL affect one another
A typical food LCA diagram
Source: http://www-mat21.slu.se/publikation/pdf/Programplan2004.pdf
Overall food-related contribution to GHG emissions - estimates
• EU EIPRO report: 31% all EU consumption related GHGs
• Various Northern European estimates @20%
• FCRN UK estimates: around 19% (probably an underestimate)
Food consumption related contribution to UK consumption GHGs (work in progress)
Non food81.6%
Catering1.5%
Agriculture7.4%
Fertiliser manufacture
1.0%
Food manufacturing
2.2%
Packaging (incomplete
data)0.9% Transport incl
overseas2.5%
Home food related2.1%
Retail 0.9%
Impacts by food type: FCRN work so far
• Meat and dairy – about 8%
• Fruit and veg - about 2.5%
• Alcoholic drinks – about 1.5%
• This is of the UK’s TOTAL GHG emissions• Similar to this Dutch study…
Contribution of food groups to Dutch GHG emissions KG/CO2e
Meat, meat products & fish, 28.2
Oils & fats, 3
Beverages & products containing sugar, 14.9
Bread, pastry &
flour, 13.3
Other food products, 3
Dairy, 22.9
Potatoes, fruit & veg,
14.6
Meat and dairy
• 8% of total emissions – why?
• Mostly a result of methane & nitrous oxide
• Most occurs at livestock rearing stage
• But meat and dairy products also the most refrigeration dependent foods
• And one of the most wasted ones.
• Wasting meat & dairy means huge waste of embedded GHGs
Fruit and vegetables
• Contributes approx 2.5% total• Trends: increasing consumption of GHG
intensive produce:– Air freighted produce: soft berries, beans &
peas, top-ups– Unseasonal protected: ratatouille vegetables– Pre-prepared: ready to eat fruit salads & salad
bags– Fragile / spoilable berries, salads
Fruit & veg continued
• These are the least ‘robust’ most easily spoiled produce - vulnerable to being wasted
Variation in how ‘wasteable’ produce is
• 10-30% strawberry crop Class II and left to rot (University of Herts 2006)
• Variations by type up to retail stage: 2% potatoes waste vs 23% strawberries (Kader & Rolle FAO 2004)
Life cycle stage Volume wasted (million tonnes)
Agricultural production 0.2?
Food processing 0.16
Retail 0.17
Food service 0.96
Domestic 2.5
Total fruit and vegetable waste 3.99
Total fruit and vegetables marketed 16
Fruit & vegetable waste as % of total supply
25%
Waste in the fruit & veg supply chain
Alcoholic drinks
• Contributes about 1.5% of total• Trends:
– More wine: relative importance of transport to grow?– More chilled: cold lagers, cider over ice, chilled wine,
spirit mixers– More in-home: more single serve packages– Hospitality sector??– More drinking: (except for this year)– Issue here is more about packaging than food waste
GHGS: Foods with major impacts
• Meat and dairy– 8% + UK estimate– 13.5% total EU GHG emissions– FAO estimates livestock =18% global GHG emissions
• Certain kinds of fruit and vegetables– Vegetarian diets not always better
• ‘Unnecessary’ foods and drinks – alcohol, beverages, confectionary– Whose needs? Who defines them?
The most wasted foods
• Fruit and veg (1)• Meat & fish (2)• Bread• Dairy (4)• Chilled ready meals (5) • High waste foods = also GHG intensive foods• Most waste occurs at household stage – once
food has ‘embedded’ all upstream GHG emissions
• (These are WRAP findings but similar to Swedish study)
Food waste & refrigeration
• Fridges stop food going off
• Better cold storage = less food waste
• Food waste = waste embedded GHG emissions
• Although refrigeration is energy intensive…. It reduces waste and associated GHGs
• A simple trade off?
Actually…. relationship not so simple
• Attitudes to food waste (WRAP)• Cost of food• Fridge as ‘safety net’• Unplanned lifestyles• If temp control is available you eat more cold-dependent
foods – ie. shapes consumption• Temp control allows long distance transport – opens
more opportunities for waste along supply chain• Refrigeration to preserve ‘quality’ rather than safety;
alters notions of quality – food discarded as sub-standard
• Technology helped reshape attitudes to food?• Tech solutions foster new problems?
Climate change impacts on food supply
Agriculture • Some positive – but largely negative• Extreme weather events / the wrong sort of weather• Changes in crop suitability• Crop and livestock diseases• Water• Poor will suffer most
Food processing and distribution• Disruptions to transport & stationary infrastructure
Consumption• Changes in consumer demand?• Consequences for food industry & household energy use?• Food safety problems?
Climate change – knock on effects
• If current sources no longer viable – need to source from elsewhere (further?)
• Weather disruptions mean increasing reliance on emergency top ups (by air)?
• Weather related spoilage / waste – recent events
• More heat related spoilage – stricter controls on food quality (more energy intensive?)
• ALL THIS INCREASES POSSIBILITY OF MORE WASTE ALONG SUPPLY CHAIN
What might less a less GHG intensive way of eating look like?
• Changing the balance of what we eat – Less meat & dairy - lower down food chain
• Seasonal field grown foods (less storage, heating & transport)– UK seasonal when possible– Elsewhere seasonal when not
• Not eating certain foods– Avoiding hothoused/air freighted produce (but
developing world?)
And…Reducing cold chain dependence (but wasting less)• The ‘two freezer syndrome’• Robust foods (including less processed)• Frequent non car based shopping / frequent turnover of
food• Eat what we buy, soon after we’ve bought it• Accepting variability of quality and supplyEfficient cooking• Cook for more people and for several days - PLANNING• Less use of oven Redefining quality• Accepting different notions of quality• Accepting more variabilitySimpler food???
Reducing food waste
• One third food bought is not eaten• The technology approach? Improve packaging,
portion size (no leftovers), extend food life span to match our lifestyles? Keep food properly refrigerated. Shrink-wrapped cucumber last longer than unpackaged cucumber
• The behaviour approach? Plan your meals, shop little and often, eat food soon after you’ve bought it, use your leftovers, compost scraps, shared living? Eat that cucumber sooner rather than later!
