Food commodity markets should stay immune to any further deterioration in the macroeconomic environment this year as tight fundamentals continue to support price levels, Patrick Armstrong, managing partner of Distinction Asset Management, said Tuesday.

Armstrong said tight fundamentals will ensure food commodities are protected from any downturn in the global economy, especially in grain markets such as corn and wheat.

The U.S. Department of Agriculture last week announced cuts to its forecasts for U.S. corn and wheat production for this year after adverse weather took its toll on planting for all crops.

Damaging heat took its toll on corn fields in July while excessive rains hampered wheat planting in the northern plains this spring, the USDA said in its monthly World Agricultural Supply and Demand Estimates report.

Still, given the recent volatility in commodity markets triggered by a downgrade of the U.S. government's credit rating by Standard & Poor's Corp. and ongoing concerns about the growing European debt crisis, "we have reduced by 1% our portfolio exposure that lies with agriculture in our most aggressive and tactical portfolio, and maintained the weight in our more conservative portfolios," Armstrong said.

At present, 5% of Distinction's aggressive portfolio exposure now lies with agriculture. Armstrong said although agriculture remained a preferred area, the asset manager is currently building up cash positions in that portfolio rather than investing cash that arrive into funds.

Distinction asset management said it expects corn, wheat and soybeans to see the most future upside. Bullish fundamentals for corn are supportive for wheat prices as both are used for feed grains.