James Ferrier, Melbourne-based analyst with Wilson HTM said a combination of two inter-related factors would mean investors would not be too enthused by GrainCorp for the short term.

GrainCorp shares have dipped about 8pc since the news broke of Mr Irwin’s departure in late January to be at $5.77 on Tuesday.

Mr Ferrier said the concerns centred equally on the $757 million purchase of United Malt Holdings and the search for a suitable replacement for Mr Irwin.

“Our concerns are not just based around the acquired earnings, but also caution on how they will go with managing the UMH business.

“The question is whether senior GrainCorp management and the board have the capability skills-wise and experience-wise to run a large and complex business in UMH.”

He said the market was comfortable with Mark Irwin and the board’s ability to manage a domestic grain business focusing on grain handling, but that did not necessarily translate to managing a multinational malting business in a competitive global market.

“We don’t have a problem with the company trying to diversify, the theory of buying a downstream asset is sound logic, but the jury is still out on how UMH will go.

“You have to factor in the size and the complexity of the asset they bought, and our view is that just because you can run an Australian grain handling business doesn’t mean you can deal with the added complexity of an international malting business,” Mr Ferrier said.

He said that dove-tailing into this were concerns on the board and senior management’s experience with the malt industry.

While interim managing director of GrainCorp Ian Wilton has experience in the sector through his time as the chief financial officer of Conagra Malt, the precursor to UMH, Mr Ferrier said the feeling was the management team and the board in particular may need more malt-specific expertise.

He said finding a good candidate to replace Mr Irwin would be a crucial step for GrainCorp to win back investor confidence.

“Getting a suitably qualified MD will be a catalyst to bolstering confidence, but the scope of these international searches means that you could not realistically expect this to occur in less than six months.”

Currently, Wilson HTM have a hold recommendation on GrainCorp, and are advising a sector preference for AWB, on the basis of AWB having a larger earnings growth profile in the short-term and the benefits associated with de-risking the business over the past 18 months via asset sales and an equity raising.