The era of cheap food - and of food becoming cheaper year-on-year - is over, according to Richard Lowe, chief executive of the Meat and Livestock Commission

Britain's pig farmers have been arguing strongly their case for higher prices in recent weeks. The stakes are high: on the one hand are retail price increases of between 7p and 17p on typical packs of pork; on the other is the continued existence of an indigenous pig farming sector. Other sectors of the meat industry - beef, lamb and chicken - are similarly under pressure and under threat.

But it's not just an issue for the meat sector. In the middle of the past century, the developed world spent one-third of its disposable income on food. Today we give over only 10%. That figure is set to start growing again.

The doubling of wheat prices that has prompted pig and other livestock farmers to press for price increases is the tip of an iceberg. Several factors are converging that will drive up the price of meat and, indeed, many foodstuffs.

A world population explosion and growing affluence in emerging economies has prompted the UN to predict that those populations will be eating 30% more beef, 50% more pork and 25% more poultry in the next decade.

The global poor may not be large percapita consumers of meat but the shift of land from food production to bio-fuels could be catastrophic. The UN has reported that the price of food aid rose 20% in a year. China halted all new planting of corn for ethanol after pork prices soared 42%.

These are global consequences that impact on local markets. The ability of major retailers and foodservice operators to source cheap meat from around the world will weaken. In the UK in particular, the supermarkets have been highly successful in driving food deflation in real terms.

Critics bemoan their importing of cheap meat and the inherent encouragement of intensive production. If Britain's farmers are forced out of business because they are paid less than the cost of producing their animals, we lose more than just our capacity to produce meat. Our ability to secure our food supply is endangered in a highly competitive global market.

Forget about cheap meat: the issue for UK consumers will be one of affordable meat - the quality of which is regarded as value for money, which has been produced to acceptable animal welfare and environmental standards and whose supply can be guaranteed.

Supermarkets now face a strategic rather than a tactical decision: the future of British livestock production as we know it is in their gift.