From dairy farms unable to keep milk refrigerated, to chickens suffocating en masse as ventilators fall idle, an energy crisis is taking a heavy toll on South Africa's food sector, industry groups said.

Record power cuts have caused shortages of some staples, threatening price rises that could make some popular items too expensive for poor families, agricultural industry body AgriSA said.

"The affordability of food is going to be a challenge particularly to the lower income household, especially with chicken which is one of the cheapest protein staples in the country," AgriSA's chief economist, Kulani Siweya, said.

Scheduled blackouts, known as load-shedding, have burdened Africa's most industrialised economy for years, with state-owned energy firm Eskom failing to keep pace with demand and maintain its ageing coal power infrastructure.

But the outages reached new extremes over the past 12 months.

Poultry farmer Herman Du Preez, said at least 40,000 of his chickens were asphyxiated last week with disruptions in power supply causing the farm's ventilation system to stop working.

"It wasn't a pretty sight to see how much money we lost due to the fact that Eskom is so unreliable," Du Preez said on Monday at his farm in the North West province.

Power cuts have also slowed down operations at slaughter houses, triggering chicken "shortages", said Izaak Breitenbach, general manager of the South African Poultry Association.

"The milk industry is also having challenges with processing their milk and the load shedding does impede on their cold storage facilities," added Siweya of AgriSA.

In a Monday newsletter, president Cyril Ramaphosa said he was aware of the "farmers that are unable to keep their produce fresh" as a result of blackouts.

But he offered no promise of ending the scheduled cuts, anytime soon.

"We must be realistic about our challenges and about what it is going to take to fix them. While we all desperately want to, we cannot end load shedding overnight," he wrote.

South Africa's record power cuts are causing shortages of some staples,and  threatening price rises that could make some popular items too expensive for poor families.

-Africa News