Ground biscuits made with two types of shortening were adjusted to moisture contents of approximately 0, 3, 6, 9, 12, 15, and 18% and stored at 43.3 °C. (110° F.) for 56 wk. Keeping quality was assessed by flavour tests, peroxide oxygen, pH, and fluorescence measurements. Although the behaviour of the biscuits was similar, and variations in moisture content had small effect on flavour scores, Biscuit A, made with the more stable shortening, gave differentially higher scores at moisture levels below 6%. The evidence from the objective measurements indicated also that a moisture content of about 6% was most suitable for storage. Changes in the fat component as measured by peroxide oxygen were inhibited as the moisture content was increased over the range studied. The formation of fluorescing substances reached a maximum at a moisture content of 12% and decreased somewhat at higher levels.