Premium
SPECTRAL STUDIES ON THE ROLE OF IONIZING RADIATION IN COLOR CHANGES OF RADAPPERTIZED BEEF
Author(s) -
KAMAREI A. R.,
KAREL M.,
WIERBICKI E.
Publication year - 1979
Publication title -
journal of food science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.772
H-Index - 150
eISSN - 1750-3841
pISSN - 0022-1147
DOI - 10.1111/j.1365-2621.1979.tb09996.x
Subject(s) - pigment , ionizing radiation , irradiation , myoglobin , chemistry , radiation , red color , sterilization (economics) , methemoglobin , orange (colour) , radiochemistry , hemoglobin , food science , biochemistry , optics , physics , organic chemistry , nuclear physics , monetary economics , economics , foreign exchange market , foreign exchange
Effects of ionizing radiation on beef pigments were studied by determining the absorption spectra of myoglobin solutions and the reflectance spectra of radiation‐sterilized beef slices. Bovine and ovine oxymyoglobin (MbO 2 ) and met(ferri)myoglobin (metMb) were extracted, purified, and treated with gamma radiation. Increasing dose and temperature of gamma radiation produced increasing shifts in characteristic peaks and progressive decreases in the Soret bands of these pigments. The total color difference (▵E), computed from tri‐stimulus values of reflectance spectra of radiation‐sterilized beef, showed similar dependence of color on radiation dose and temperature. Re‐irradiation of beef allowed to brown in air caused the unstable red pigment to re‐form. The presence of oxygen in the container during radiation‐sterilization reduced the red color formation. The results show that ionizing radiation reduces the heme iron of the brown pigment of cooked meat (globin myohemichromogen) to an unstable red pigment (globin myohemochromogen), which, upon exposure to air, reverts to the original ferric (brown) pigment.