Investigation of the use of mulberry leaf in further processed poultry products

Mulberry leaves are known for their rich nutritional content and health benefits. The potential use of mulberry leaves in advanced processed poultry products is being researched to enhance product quality and provide health benefits. The aim of this study is to examine the effects of different concentrations of white mulberry leaf extract (WMLE) on the physicochemical properties, microbial quality, lipid oxidation, color stability, and texture characteristics of nuggets during 21 days of cold storage. Nuggets were treated with 0.1% and 0.5% WMLE, and the results were compared with control (NC) and nuggets with 0.1% BHT added (N-BHT). The pH values of all groups tended to decrease over time, and the addition of WMLE caused a decrease in the pH values of the nuggets (p<0.05). The N-0.5 and N-1 groups maintained stable moisture content over a certain period, whereas the moisture content in the NC and N-BHT groups decreased over time (p<0.05). The TBARS value, indicating lipid oxidation, significantly increased in the NC group to 0.34±0.02 by the 21st day compared to the other groups. The bacterial count in the NC group reached 7.38±0.09 log CFU/g, in the N-0.5 group 6.9±0.29 log CFU/g, in the N-1 group 7.68±0.01 log CFU/g, and in the N-BHT group 7.34±0.50 log CFU/g by the 21st day (p<0.05). Total enterobacter counts were measured as 2.43±0.04 in the NC group, 1.35±0.20 in the N-0.5 group, 1.94±0.08 in the N-1 group, and 2.77±0.14 in the N-BHT group at the end of 21 days (p<0.05). The redness value (a* value) of the nuggets decreased (p<0.05) and overall color acceptability increased, while texture parameters remained stable and were found acceptable by consumers (based on 1-9 scoring value). The use of WMLE extended the shelf life of nuggets by limiting microbial growth and lipid oxidation, and improved color and texture characteristics. These findings support the use of WMLE as a natural coating additive in advanced processed poultry products.