Influential midfielder Anatoly Tymoshchuk is being treated on a drip while striker Andriy Voronin is also ill.
"Tymoshchyk is still in bad condition, we have got him on a drip. And this is not funny. We have to wait for the doctors' verdict but the situation is far from funny," Blokhin told reporters after the defeat in Ingolstadt, Germany.
"I do not know the reason for the illness because we all ate different food. We have one week to recover... it's good that it did not happen on June 11."
Ukraine, who suffered their second successive friendly loss after a 3-2 defeat against Austria last Friday, begin their Group D campaign against Sweden in Kiev on Monday.
Blokhin said defender Bohdan Butko and midfielder Denys Garmash were also afflicted but were well enough to start against Turkey.
"If Butko and Garmash refused to play I could have cancelled the game because of a lack of players," he said.
Goals from Caner Erkin and Mustafa Pektemek were enough to secure victory as Blokhin's hastily rearranged lineup failed to gel.
Pektemek set up Erkin to score on the half-hour but Ukraine, outplayed in the first half, improved after the break and Turkey goalkeeper Mert Gunok was forced to parry Yaroslav Rakitsky's header at full stretch.
Substitute Andriy Shevchenko then headed a clear chance wide and also chipped against the crossbar.
Pektemek sealed victory for Turkey when he beat the offside trap and lobbed keeper Andriy Pyatov on 69 minutes.
