Shares in the AIM-listed bulk logistics specialist dropped 8% to 5.62p, their lowest since October last year, after starting 2013 at 7.5p and hitting 9.3p in January.
Incoming chief executive Loek Kullberg said: "Our 2013 financial year has been very challenging and, despite some good work, we are disappointed by the level of profitability achieved."
InterBulk was part of Mr McColl's Clyde Blowers group until it was listed on AIM in 2007, but he remains a non-executive director and 3.57% shareholder.
The group had warned in October that profits would be hit by the failure of European economies to recover this year as expected, also citing volatility prompted by polymer price pressures and chemical plant shutdowns.
Mr McColl said: "It has been fairly good on the liquid bulk side, it is the dry bulk side that has struggled this year, mainly because of the downturn in economies where you have got dry chemicals, but I think we see it as a temporary dip."
He added: "One of the keys is we now have Sinotrans as one of our major partners. Chemical manufacturing is moving from the west to the east, that is part of the change we are seeing I think there is strong growth in that area."
Mr Kullberg said recovery in dry bulk was top priority, after a year which saw the division's core operating profit fall from £6.1 million to £1.8m. He said: "We have a clear strategy for growth which recognises the limitations of our traditional dependence on certain geographies and the polymer sector, with targets for food grade cargo and activity outside Europe."
InterBulk's liquid bulk division maintained core profits steady at £7.7m, while its foodstuff cargoes increased by 9%.
The group, which employs around 200 of its 500 staff in the UK, reduced net debt by £3.1m to £69.5m.