Is our supermarket produce all it seems to be? Author and food industry expert Suzanne Lockhart, lifts the lid on what could be lurking underneath

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The first time I noticed just how much fruit and vegetable production had changed, certainly from my early days running down to the greengrocer for my granny, was when I was visiting supermarkets on Vancouver Island in 2005. I was working on a marketing project with a leading Canadian retailer and had the privilege of being ushered around their stores to see the way food was promoted on the Pacific Coast. I still remember seeing the apples on display at the front of the store – they were magnificent. Each perfect fruit was cartoon red – straight out of a scene from Snow White and the Seven Dwarfs. Glistening under the carefully designed overhead lighting and displayed with military precision, these apples were so polished I initially thought they were fake – a marketing display only. To check, I picked one up to see if they were real.

I was quite taken aback and turned to the manager who was looking a little confused. ‘Wow, these look amazing – are they locally produced?’ I thought they must have been imported given it was February with sub-zero temperatures outside. He replied, ‘Yes. We have a great produce team who look after our fruit storage.’ I wondered what on earth he meant. Did they tuck them up in bed at night and sing lullabies to the apples, or were they individually polished every evening by the hands of virgins? Turns out the apples were sprayed every night but apparently the real magic occurred long before the fruit arrived in the store.

SmartFresh is now used on a wide range of fruits and vegetables in over 26 countries, including the UK, US and Australia

In North America, apples generally ripen between August and September. They are picked when slightly unripe, sprayed with a chemical called 1-methylcyclopropene (1-MCP), waxed (with a petroleum-based agent), boxed, stacked on pallets and then kept in a cold store for up to 12 months! The spray is known as ‘SmartFresh’ and in 2011 the Canadian government expanded this treatment so that apples can now be sprayed with this chemical up to four times during storage.

So when you select your delicious-looking apples from your supermarket, thinking you are ‘doing the right thing’ and eating healthily, you are possibly buying an apple that was picked over a year ago! SmartFresh is now used on a wide range of fruits and vegetables in over 26 countries, including the UK, US and Australia. So the fresh produce you are buying in the local supermarket is actually not that ‘fresh’ at all.

Fruit and vegetables contain the maximum nutritional value the moment they are harvested. The longer they are in storage the more their nutritional value deteriorates. Studies show SmartFresh reduces the antioxidant (vitamin) levels in fruits. Petroleum-based wax, used to preserve fruit and vegetables, is also used on other produce including cucumbers, potatoes, oranges, bell peppers, limes, lemons, aubergines and courgettes. This coating locks in any pesticides and herbicides used when growing the plants, making it very difficult to remove when washing at home. Even if you peel your fruit or vegetables they have often been sitting in storage so long that the pesticides have soaked all the way through, so even if you remove the skin you are probably still eating pesticide residue.

This is very different from the odd-shaped, dirt-caked fruit and vegetables my granny bought in brown paper bags from the local greengrocer. There were no preservatives so we only ate what was in season. No one worried about the ‘air miles’ the food travelled because it didn’t travel far. It couldn’t travel far because there were no preservatives to keep it in tip-top condition. We knew what we were eating was fresh because otherwise it would be rotten within days. The fruits and vegetables my granny ate delivered the micronutrients she needed but the mass-produced, mass-preserved, sprayed and polished ‘fresh’ produce available in many supermarkets may not.

A landmark study published in 2004 in The American College of Nutrition journal showed a ‘reliable decline’ in the amount of protein, calcium, phosphorus, iron, vitamin B2 and vitamin C found in fruit and vegetables over the past 50 years. Comparing the nutritional data of produce from 1950 to the nutritional data of produce in 1999, scientists reported declines in other nutrients such as magnesium, zinc, vitamin B6 and vitamin E.

we would have to eat eight oranges today to get the same amount of vitamin C our grandparents received from just one orange

The Organic Consumers Association in the US cites several other studies with similar findings: a Kushi Institute analysis of nutrient data from 1975 to 1997 found that the average calcium levels in 12 fresh vegetables dropped 27 per cent; iron levels dropped 37 per cent; vitamin A levels dropped 21 per cent; and vitamin C levels dropped 30 per cent. A similar study of British nutrient data from 1930 to 1980, published in the British Food Journal, found that in 20 vegetables the average calcium content had declined 19 per cent; iron had dropped by 22 per cent; and potassium by 14 per cent. Yet another study concluded that we would have to eat eight oranges today to get the same amount of vitamin C our grandparents received from just one orange.

And to make matters worse it’s not just the drop in micronutrients. Many of the pre-packed produce we have come to rely on, such as mixed salad leaves, are washed in chlorine (one of the bad halogens) before being packed in modified atmospheric packaging. This method of preparation and packaging also reduces the amount of oxygen in the bag while filling it with carbon dioxide. Research from the Rome Institute of Food and Nutrition shows that salad preserved using this method loses its antioxidants just as quickly as lettuce left to go off naturally. In other words, by the time the leaves are eaten they may still look ‘fresh’ but their micronutrient value is almost non-existent.

Don’t get me wrong, it would be ludicrous to suggest that all fruit and vegetables today have very little nutrition, and we would be crazy to stop eating them. But the hard facts speak for themselves. The fresh produce enjoyed by our grandparents was substantially more nutritious than the fresh produce we eat today.

So, where possible:

1. Grow your own. If that’s not possible, or you don’t have the time or inclination, then…

2. Source a local producer that grows fruit and vegetables traditionally and buy direct. Many farm shops now offer online ordering and delivery options; check out the ‘pick your own’ venues – make a day of it and gather up some fresh ‘in season’ goodies. Farmers’ markets are also a great place to buy locally produced fresh fruit and vegetables. If that’s not possible or you don’t have the time, then…

3. Buy organic. Often organic produce is more expensive so you may have to buy a little less. If there are limited organic options in your area, then…

4. Take dietary supplements to ensure you are getting the necessary micronutrients.

This is an extract from  Mad Diet by Suzanne Lockhart , published by Coronet. £14.99.

British author Suzanne Lockhart was Vice President of a multinational food science organisation for 10 years. In a career spanning over 20 years working with government agencies, global food manufacturers, farming groups and grocery retailers, she has insider knowledge of the politics and production of our food. After being diagnosed with depression in 1989, Suzanne has spent over two decades investigating the impact of a Western diet on physical and mental health.

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