摘要:In this study, the possibility of using thermally processed fatted and defatted soy flours samples of biscuits were investigated to fortify the biscuit flour without damaging the quality. For this purpose, fatted and defatted soy flours were first thermally processed at 110 oC for 2 hours and then were added to biscuits flour at 2%, 4%, 6% and 10% levels and finally petit beurre biscuits were produced from these fortified flour samples. Mathematical-statistical method was applied in calculating the shelf-lives of biscuit. The calculated of shelf-lives differs depending on quality criteria. The most important properties in terms of limiting the shelf life of biscuits are taste, odour and acidity degree. According to the finding: the addition of 2% fatted, 2% defatted and 4% defatted soy flours were found to have better biscuit properties.