Comparison Between Traditional Deep-Oil and Microwave Puffing for Physical and Eating Qualities of Puffed Pork Rind

Abstract

The effects were characterized and compared of pretreatment process conditions (boiling at different sodium chloride solutions of 0, 3, 4 and 5 % and drying at different dehydration times of 4, 5 and 6 hr) on the moisture content prior to puffing (MCP), volume expansion (VE), the moisture loss after puffing (ML), hardness and the color difference between microwave puffing (MWP) and deepoil frying puffing (DOFP). The optimal pretreatment process conditions were selected by means of response surface methodology that considered the desirability and was validated by sensory evaluation. It appeared that the addition of salt increased the MCP associated with the puffing processes. The VE and hardness were affected differently by the two techniques with the values of DOFP being better than those of MWP values in general. MWP resulted in samples with a higher lightness but a lower color intensity when compared to those of DOFP. The results suggested that gelatin together with MCP might play an important role in MWP. Although being inferior compared to DOFP at different pretreatment conditions, MWP showed some comparable efficiencies in the puffing process and sensory evaluation under the optimal conditions which consisted of boiling in 3% salt and drying for 5 hr for MWP, while for DOFP, the optimum conditions were boiling in 0.003% salt (approximately water only) and drying for 6 hr when compared to the commercial product.