Citric acid and sucrose pretreatment improves the crispness of puffed peach chips by regulating cell structure and mechanical properties

Abstract

Crispness is an important textural attribute of puffed snacks. Impregnation pretreatment is used to regulate the texture of puffed products by changing the cell structure and mechanical properties. In this study, the influence of citric acid and sucrose pretreatment on the cell structure, cell wall components, and mechanical properties of peach slices before puffing drying (heat-pressed slices) was evaluated to understand how citric acid and sucrose pretreatment affects the pore structures and texture characteristics of peach chips with improved crispness. Cell wall degradation, cell structure morphology and mechanical properties before puffing drying interacts to govern the pore morphology and texture characteristics of peach chips. Micrographs of heat-pressed slices showed swollen structures for Cit (citric acid) treated samples and compacted structures for Cit + Suc (citric acid and sucrose) and Cit + Suc + Sdp (citric acid, sucrose and sodium dihydrogen phosphate) treated samples. An increased elastic modulus and decreased viscosity index were observed in all Cit-, Cit + Suc- and Cit + Suc + Sdp-treated samples. After puffing drying, Cit prompted the generation of large pores with low hardness, and Suc and Sdp enhanced the emergence of uniform and small pores with increased hardness. Therefore, crispness was attained by regulating crumbly texture through Cit and regulating hard texture through Suc and Sdp.