CMC-regulated multi-chamber formation contributes to the texture of deep-fried batter-coated meat strips: multiple visual evaluation collaborative water/oil migration analysis

Abstract

A soft texture in the interior with a crispy exterior is essential for deep-fried batter-coated meat strips (BCMSs). This study investigated the effects of carboxymethyl cellulose (CMC) on the batter properties and gel structure of wheat starch–flour blends. Various visual techniques, such as scanning electron microscopy (SEM), three-dimensional magnetic resonance imaging (MRI), and infrared thermography, were employed to analyze the transfer of water/oil/heat between the medium, crust, and core meat to reveal the effects of changes in gel properties on the texture of deep-fried BCMSs. As the content of CMC increased, the batter viscosity initially remained unchanged and then increased. Results of the coating pickup and rheological tests showed that the CMC-0.75 % had the thickest coating and the poorest gel stability, which resulted in thick crust gel fracture, forming large chambers. According to the MRI and infrared thermal imaging results, large chambers facilitate the transfer of heat and oil to the core meat, thus enhancing crust crispness but decreasing meat tenderness. Comparatively, 0.5 % CMC improved the integrity and viscoelasticity of the crust gel network. The complete gel network inhibited the unfolding and reaggregation of muscle proteins caused by oil and heat transfer, which mitigated the degree of meat protein denaturation, thus protecting tenderness. Meanwhile, delaying protein denaturation reduced water migration from the meat to the crust and improved crispness. Thus, a moderate addition of 0.5 % CMC ensured a soft interior texture with a crispy exterior for fried BCMSs.