At low relative humidity (RH), an edible wheat gluten film presents very low oxygen and carbon dioxide permeabilities [1.24 and 7.4 amol/(Pa m s), respectively, at 25 °C]. For higher than 60% RH, O2 and CO2 permeabilities increase exponentially [to 1290 and 36 700 amol/(Pa m s), respectively, at 95% RH], presumably due to the plasticizing effect of water molecules. Pectin, chitosan, pullulan, and myofibrillar protein films are also very permeable to O2 and CO2 at high RH. The selectivity ratio (CO2/O2 permeability) of all films tested at high RH was very high (from 10 to 28) as compared to conventional synthetic films (4 to 6). Keywords: Edible film; gas permeability; relative humidity

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Precise measurements of the band origins of the 2Π½—2Π½ and ∏212−∏212 subbands of the fundamental of nitric oxide and of the band origin of the 1–0 ∏212−∏212 satellite band provides accurate values for the spin—orbit coupling constants A0 and A1 for the v=0 and v=1 vibrational levels. The values obtained are A0=123.160 cm—1 and A1=122.911 cm—1. When these results are combined with the results of Olman, McNelis, and Hause, precise values of A2 and A3 are also obtained. They are A2=122.658 cm—1 and A3=122.360 cm—1. Causes for the discrepancy in A values calculated from other investigators' results are discussed. Certain discrepancies in rotational constants obtained from this and other infrared studies are pointed out and briefly discussed.