During vacuum-packaged frozen storage of fatty goose liver ("foie gras"), a yet unknown, but fully reversible (package opening and thawing), greening was found at a Hungarian processing plant. Laboratory analysis revealed hydrogen sulfide (H2S) and remnant blood in 35 livers. Microbial spoilage was under the limit of detection for H2S-producing strains. In liver homogenates and in thawing exudates, sulfhemoglobin was found and confirmed (acid-alkali reactions), with spectrophotometric analysis. Slaughtered geese are chilled to 2C (24h) in a non-eviscerated condition to maintain liver shape. With logistic regression, the H2S (most probably from the intestinal tract) was of primary importance in the green color development. In an experimental group (n=10) dissected after 2h of body chilling, H2S was absent in the liver. Results indicate that intestinal tract-originated H2S is diffusing the fattened goose liver, leading to a color defect of a delicatesse, without consumer health risks.
ASJC Scopus subject areas
- Food Science
- Safety, Risk, Reliability and Quality