Causes of Can Swelling and Blackening of Canned Baby Clams. II. Bacterial Action Involved in Can Swelling and Blackening of Baby Clams

Abstract
SUMMARY—: Six strains of bacteria (three involved in blackening, two in swelling, and one in both blackening and swelling) were isolated from blackened meat of baby clams in swelled cans. Of these bacteria, certain species which may be related to the blackening may decompose hemocyanin to liberate copper. The bacteria involved in blackening form hydrogen sulfide by decomposing sulfur‐containing amino acids such as cysteine. The hydrogen sulfide produced reacts with copper and iron to make sulfides, and blackening occurs. Spoiled clams seldom contained only one species of causative bacteria. Both meat blackening and can swelling may possibly occur in the same pack of canned baby clams.