Determination of some quality properties of cookies with lemon peel powder

In this research, the usability of lemon peel powder (LPP) in the production of functional cookies was studied to recycle lemon waste and to benefit from its bioactive components. Firstly, the peels were separated from the cleaned lemons, dried in an oven, and then ground. Cookies were prepared by adding LPP at the rate of 0-2-4-6-8-10 %. Chemical, physical, and sensorial analyzes, the contents of total phenolics and vitamin C, and antioxidant capacity (ABTS radical scavenging activity and FRAP) were carried out. With the addition of LPP to the cookies, an increase in the amount of crude fiber, total phenolics, vitamin C, and antioxidant capacity was observed. The cookie with 2 %-10 % LPP, there were an increase of 11.76 %-55.38 % in crude fiber, 10.29 %-30.04 % in total phenolic content, 9.63 %-88.11 % in FRAP and the cookie with 4 %-10 % LPP, there was an increase of 19.60 %-20.07 % in ABTS radical scavenging activity. Also, the spread ratio of the cookies increased with an increase in the LPP, while the hardness and brittleness values decreased. According to the sensorial evaluation, the bitterness, sourness, aroma, and odour of the cookies increased with an increase in the LPP. The general acceptability was increased up to the LPP 6 % and then decreased. Consequently, the cookies with the LPP were a good source of crude fiber, total phenolic content, vitamin C and antioxidant capacity and LPP at 4 %- 8 % levels can be used for production of cookie.