* AB InBev quarterly profit flat on previous three months
* Firm had warned of weakness after strong second quarter
* Shares fall 10% in early trading (Updates shares, adds details on affordable beers)
By Philip Blenkinsop
BRUSSELS, Oct 25 (Reuters) - Shares in Anheuser-Busch InBev tumbled 10% on Friday after the world's largest brewer lowered profit growth forecasts for this year after drinkers in Brazil and South Korea turned away from its beers in a weak third quarter.
The maker of Budweiser, Corona and Stella Artois previously predicted strong growth of revenue and core profit, or EBITDA, this year. On Friday, it forecast only "moderate" growth in EBITDA -- earnings before interest, tax, depreciation and amortisation -- citing a "challenging" July-September period.
The Belgium-based company's third-quarter core profit was unchanged year-on-year at $5.29 billion, missing market expectations for a 3% rise.
Shares in the firm were down 9.9% at 74.68 euros in morning trade after hitting a near five-month low, making them the weakest performers in the FTSEurofirst index of leading European stocks.
AB InBev had warned of some weakness after a strong second quarter when its beer sales rose at their fastest pace in more than five years.
Shipping beer to China had been disproportionately higher in the second quarter because of promotions, and so they were lower in the third. Costs rose because of higher aluminium and malt barley costs and due to the weaker currencies of some of its markets, notably the Brazilian real.
Sales and marketing costs were also higher than in the third quarter of 2018. Last year, such costs were skewed towards the first half of the year because of the soccer World Cup.
Beyond these anticipated items, the company also suffered lower beer sales in Brazil and Korea as it increased prices in weak consumer markets.
In Brazil, AB InBev's second largest market behind the United States, the company saw beer its volumes drop by 3% as some competitors sold their beer at a discount to consumers, who have been feeling pressure on their real disposable income.
Brazil's economic performance has been erratic, reporting a contraction in the first quarter. The central bank has raised its growth forecast for 2019 to 0.9% but cited a high degree of uncertainty.
In South Korea, where AB InBev is the market leader, the firm hiked beer prices in April, but rolled them back this month because of an economic slowdown and after rivals failed to follow suit.
South Korea's trade-reliant economy has been among those worst hit by cooling demand as a prolonged U.S.-China tariff war disrupts global supply chains. Its economic growth slowed more than expected in the third quarter.
AB InBev said it still expected strong overall revenue growth in 2019 but said the challenges of Brazil and South Korea would continue into the fourth quarter, so the company only expected "moderate" growth of core profit.
Economic challenges in other markets, including Argentina and South Africa, also led the company to push more affordable lagers, meaning revenue per litre growth would be slightly behind inflation. It previously forecast above inflation growth.
AB InBev has generally sought to push drinkers towards more expensive beers. In developing markets, its focus has been to win over customers to beer and encouraging them to buy slightly more expensive brands in larger bottles that keep down prices.
In other business, AB InBev has sold its Australian subsidiary Carlton & United Breweries to Asahi for $11 billion and raised about $5.6 billion for a second attempt to float part of its Asian business.
The brewer has said it will use the proceeds to pay off debt, which stood at more than $100 billion after its 2016 purchase of nearest rival SABMiller.
On Friday, it said the sales would reduce its net debt to EBITDA ratio below four times at the end of 2019, a year ahead of target, from 4.61 at the end of June.
$1 = 0.9002 euros Reporting by Philip Blenkinsop; Editing by Christopher Cushing and Edmund Blair