Fourier Transform infrared (FTIR) spectroscopy was used to monitor structural changes in lipids and proteins in four species of pollen grains at different temperatures. Spectral data were used to determine membrane phase transition temperature ( Tm) in pollen at two hydration levels. Imbibition was conducted at temperatures above and below the determined Tm values to correlate damage to the presence of gel phase. For three species of pollen, hydration overcame imbibitional damage at low temperature. However, dry pecan pollen, which had a high lipid content, was injured during imbibition at temperatures above and below the Tm. Changes in protein structure were not related to imbibitional damage. FTIR spectroscopy is a useful tool in examining biochemical properties of intact pollen grains and has potential for evaluating cryopreservation protocols.