Mr Mackay spent 35 years at SAB Miller, steering its transformation from a South African industrial conglomerate to the world’s second-largest beer maker with annual sales of $34.5bn and 200 brands including Miller Lite, Peroni and Pilsner Urquell. He helped steer the consolidation of the brewing industry through a string of acquisitions over two decades that began following the release of Nelson Mandela in 1990 and the lifting of sanctions on Mr Mackay’s native South Africa.
He was chief executive from 1999 when the company – then called South African Breweries – listed on the London Stock Exchange, until April this year when he took a medical leave of absence following surgery on a brain tumour.
Mr Mackay recovered enough to resume his duties as chairman in September but his condition suddenly worsened in November, and he took a further leave.
He died peacefully, the company said, surrounded by his family, which includes three adult sons and three school-age sons from two marriages.
With a background in engineering, Mr Mackay had a reputation for knowing all there was to know about beer, including the science involved in its production.
“He put things in very understated and clear terms,” said Anthony Bucalo, beverage analyst at Santander.
“He was always a fair-dealing, honest CEO who treated the analysts and investors around him, and his operators, with a great deal of respect.”
South African Breweries traces its roots to the dusty gold prospecting fields around Johannesburg, where it began selling beer in 1895.
By the time Mr Mackay joined in 1978, its interests ranged from food to property but it exited those businesses as it moved further into beer.
In the 1990s, as chief operating officer, Mr Mackay embarked on a series of acquisitions in eastern Europe, Africa and China that, while relatively small, were viewed as bold bets on undeveloped markets.
The bigger deals that put SAB on the global stage, such as Miller Brewing in the United States and Bavaria in Latin America, came later once the company was flush with capital from its 1999 London listing.
“I’ve been extraordinarily lucky because I happen to have been running the show at the time when it was without doubt the most exciting period in the world beer industry that there’s ever been and it can’t happen again either,” Mr Mackay said in February.