A second study from manufacturers of food packaging aims to drive home the point that the products from those companies are not too contaminated for curbside recycling.

The recently conducted effort from the Foodservice Packaging Institute follows the first segment of the report, which was released at the end of last year.

The latest research looked at a sampling of 2,600 pounds of residential recyclables collected in southern Delaware. Researchers separated the material into two categories – foodservice packaging and other packaging in contact with food – and then went through the loads on an item-by-item basis. Products were given one of three ratings: high food residue contamination, medium or low.

The two categories proved to have roughly the same proportion of low- and high-level contaminated products, according to FPI’s report. The foodservice packaging had a slightly higher proportion of medium-level contamination.

FPI’s earlier study, which looked at samples collected in Boston, found roughly similar contamination levels across the board when looking at foodservice packaging and other materials that came into contact with food residue. Together, FPI stated, the two studies indicate tubs, lids and other material categories in the foodservice realm should be regularly included in residential recycling streams.

“One of the most common reasons that municipal programs do not accept foodservice packaging is the concern about increased levels of food contamination in recyclables,” Lynn M. Dyer, president of FPI, said in a press release. “The encouraging results of the Delaware study provide us a different representative sample of food residue on foodservice packaging. They assist in corroborating our findings of foodservice packaging residue as a perceived barrier in recycling programs rather than a real obstacle.”

A recent study on food residue in packaging aims to bust the myth that food service packaging is too contaminated to be added to recycling streams.

The Foodservice Packaging Institute (FPI) released preliminary findings from a food residue study carried out in Boston. With the help of DSM Environmental Services, roughly 2,000 pounds of randomly selected curbside recyclables were collected and subjected to a “visual ranking system.”

According to FPI’s study overview, “there was no appreciable difference in contamination rates” between foodservice packaging and non-foodservice packaging, except when it came to foodservice corrugated containers, which exhibited slightly higher contamination levels. The study does note, however, that more research needs to be done in the field.

Another notable finding: Bostonians apparently do an impeccable job cleaning recyclables. “All of the recyclables were exceptionally clean … when compared to other recycling sorts,” the study states, and concludes that the findings, therefore, “may not be representative of recycling set outs in other cities.” In addition, the relatively small sample size – and the small percentage of foodservice packaging recyclables found – suggests that testing at higher levels might provide a clearer picture of the “real or imagined barrier” stopping many MRFs from accepting foodservice packaging.

Framing the study as “a first look at the issue,” FPI adds that its analysis “provides at least a promising potential.”