I’ve been at the BRC for about four-and-a-half years and I spent about seven years at the National Farmers’ Union before that. Our members include companies that sell over 90 per cent (in value terms) of groceries in the UK, including all the big supermarkets.

An argument frequently put forward in discussions about food is that supermarkets are the enemy both of farmers and the environment. I want to explain why these criticisms are misplaced.

Although they don’t directly deal with many farmers, retailers’ relationship with them is much stronger than any other part of the food industry. If you take the dairy industry, for example, the top 10 prices paid at the ‘farm gate’ for milk are all paid by retailers. That makes sense because retailers need a sustainable supply of milk and reward their farmers to ensure they can reinvest in their businesses.

As consumers have become more concerned about food security and ensure they are getting the right type of food in terms of provenance, retailers are increasingly working with groups of farmers very closely to make sure that they can meet that demand. In turn, retailers reward these farmers through the prices they pay. Retailers not only pay a sustainable price, but also feed back information about consumer demand so that farmers can then adjust their production.

The problem is that retailers don’t account for the whole of the food market. Going back to the dairy industry, all the retailers are paying well above the average milk price. But less than 50 per cent of milk produced by UK farmers is sold as liquid milk by food retailers; the rest of it goes into processed products, which could be anything from skimmed milk to yoghurts. The milk in those products is bought by processors and manufacturers and the final price is influenced by global commodity prices.

UK food retailers have little influence over that other half of the market, so it’s completely wrong to blame food retailers for unsustainable prices.

The good thing about the food debate at the moment is that the UK government and others are putting a lot of evidence and information into the public arena, helping to dispel the myths about our supply chains and challenging pre-conceived ideas about how our food is produced and sold.

Supermarkets have driven improvements in the way our food is produced and sold. Food is now of a higher standard than it was in the past: it’s more traceable, it’s safer, and yet it is getting steadily cheaper in real terms. That’s because supermarkets have reacted to what consumers want and passed on that demand back up the chain by working with farmers and producers. By driving efficiencies to make sure consumers get what they want at the right price, we have a better product with better labelling than ever before. Improvements in food and clearer information are helping to tackle some of the well-known problems of nutrition and provenance, and delivering the main changes in food that we all need.

There have been concerns expressed about supermarkets using their buying power to squeeze out smaller producers. Of course, in promoting greater efficiency, we’ve seen less efficient farmers, processors, and retailers going out of the market; that is inevitable, but it doesn’t diminish our support for the UK supply chain.

It also doesn’t mean the end of all small producers. In fact, many goods, including niche products and regional produce, have experienced a big growth in interest. In those areas it’s actually small producers that have an advantage over large producers because they can use sourcing and the story around the product to their advantage. As our market fragments further and we develop a more mature food market, there will be more opportunities for small producers, giving consumers something different and interesting.

When it comes to the question of sustainability, critics often point to supermarket distribution systems and claim that they are environmentally inefficient. How, they ask, can it make sense to move big lorry loads of food up and down the country? Recent reports by the Cabinet Office and others have highlighted that this type of analysis is far too simplistic. What you need to look at is the environmental impacts throughout the chain.

For example, it may be better for the environment to grow tomatoes in Spain and ship them to the UK rather than raise them here in heated glasshouses or polytunnels. We need to assess what is sold in terms of its overall impact, including the use of water and energy and the emission of greenhouse gases. That’s what supermarkets are doing and working with government policy makers to highlight the contribution our supply chains can make in reducing environmental impacts. Supermarkets’ supply chains are highly sophisticated and efficient and constantly under review to reduce the impact on the environment.

That’s a more sophisticated approach than simply saying we need everything to be produced and sold locally. Even where you have local production, for example, you may have multiple van journeys taking the produce from one farm to another to a market in another town. That could actually be less efficient and more of a burden on the environment than highly centralised, very efficient supply chains. Food retailers’ supply chains are looked on enviously by other industry sectors because they are so efficient.

Taking a look at the wider picture, it’s a good time to have a wider discussion about food. There are so many demands that we make on food in terms of the environment, health and nutrition, and ethical support. I think we’d all agree that we need to aim to have a food system that is affordable, accessible and also pays true attention to its impact on the environment. The problem has been how to meet so many diverse demands.

While it is easy to blame a small number of big companies for problems, it is easy to forget that our food market is actually driven by consumers. Academics and policy makers often aspire to a different kind of food supply chain, but if you can’t take consumers with you, then you can’t make that change. It’s the people going to the supermarket every week to buy food that really drive the changes that are made.

The best thing we could do is give consumers a better understanding of food and what it means for us: constructing a healthy diet; understanding the impacts of the various processes that go into providing food; appreciating that the bulk of food waste is created in the home and learning how to reduce that.

Consumers hold all the cards. The problem is that consumers tend to react to things on the basis of a lack of knowledge and that’s what needs to change. For example, cast your mind back to when we trialled genetically modified (GM) foods in the UK. It was consumer reaction that ended that, and that’s why retailers don’t sell GM foods in this country. On the other hand, look at the growth of free-range eggs in supermarkets (and now even in processed products). That’s driven by consumers saying they now understand this element of animal welfare and want a product that has better welfare standards.

The market is incredibly effective in driving change in the supply chain and moves quicker than any intervention. Consumer demand is key and that relies on consumers understanding the issues and reflecting that in their shopping choices. Some issues are more complex than others and may take consumers longer to grasp but they will continue to drive improvements in the way our food is produced and sold in the UK.

This article is based on an interview by Rob Lyons.

Andrew Opie is food policy director at the British Retail Consortium.