Effect of assisted drying methods on the microstructure and related quality attributes of fried chicken nuggets

Abstract

The potential for reducing oil uptake by applying aided pre-drying techniques (microwave, infrared, and convective hot air) was studied on chicken nuggets. Convective hot air (60, 80, and 100 °C); microwave (20, 40, and 60 W); and infrared (150, 250, and 400 W) drying techniques were used to pre-treat chicken nuggets between 1 and 11 min based on preliminary study before frying at 170 °C for 3 min. Standard laboratory methods were employed to assess the quality attributes of fried chicken nuggets, including oil and moisture content, colour, and texture. By comparing the micrographs obtained from chicken nuggets pre-dried using the three pre-dried methods (Microwave, conventional hot air and infra-red), chicken nugget pre-dried using microwave at 60 W have lesser oil cracks (18.05 %) when compared to the rest pre-dried method.Pre-drying substantially lowers moisture content, with microwave pre-drying being most effective, particularly at higher power levels (19.38 ± 1.36–43.11 ± 0.10). Microwave pre-drying densifies the nugget structure, reducing oil absorption during frying (13.15 ± 0.13–28.38 ± 0.12). Microscopic examination of chicken nuggets pre-dried using three methods (microwave, conventional hot air, and infra-red) reveals that those pre-dried with a microwave at 60 W exhibit fewer oil cracks (18.05 %) compared to the other pre-drying methods. It also affects (p < 0.05) the nugget colour, with higher power levels and longer drying times resulting in a darker (10.12 ± 0.01–25.29 ± 0.15) and less yellow nuggets. Texture is also significantly (p < 0.05) affected, with higher power levels and longer drying times leading to increased hardness and chewiness (158.20 ± 1.49–438.14 ± 1.89; 88.00 ± 0.93–165.79 ± 0.86; 96.20 ± 1.44–210.60 ± 0.45). Based on the findings, microwave pre-drying at 60 W for 11 min is recommended for achieving low oil content while maintaining good internal structure in fried chicken nuggets.