The use X-ray micro-CT for characterization of micro-structural properties of deep-fat fried breaded chicken nuggets

Micro-structural properties are critical in food quality assessment, product development and process optimization. The use of X-ray micro-CT for food microstructural evaluation is still relatively new and recent studies have shown that the technique has the potential to elucidate microstructural properties of food with greater details and resolution than some other imaging techniques such as microscopy. It gives images in 3-D for better quantitative assessment; involves minimal sample preparation and allows scanning under native environment. This technique was used to study the microstructural properties of breading coating and chicken core parts of deep-fat fried breaded chicken nuggets to obtain microstructural parameters that are useful in quality assessment and process modeling. The results obtained showed a significant (P<0.05) influence of frying conditions on microstructural properties of the deep-fat fried breaded chicken nuggets. The porosity of the breading coating increased while that of the core remained relatively unchanged with frying time. The number of pores also increased with frying. The chicken nuggets coating and core pores showed a decreased interconnectivity after frying. The shapes of the samples' pores were between plate and rod-like structure. The pore size distribution for the coating and the core parts showed an increase in pores with diameter <100μm in terms of volume and number count. Some correlations were observed between the sample's (coating and core) porosity and frying time, fat content and moisture loss.