Optimization of Loquat Puree Color Protection Formula and Quality Change During Storage

Abstract

In order to reduce the enzymatic browning of loquat pulp during the pulping process and to maintain the original color of the pulp, the color difference value (ΔE) was used as the main response variable. The effect of six color protectors in protecting loquat pulp from pulping was investigated and the two best performers were selected for the central composite design (CCD) test. Based on this, an investigation was conducted into the effect of composite color protection on the color and the content of nutrition of loquat pulp during storage at 5 ℃ for 28 days. Out of the six color protectors, the results indicated that ascorbic acid and phytic acid had a significant impact on color protection, and the optimal ratio included 0.332% ascorbic acid, 0.065% phytic acid. The verification test showed the average ΔE of loquat pulp after composite color protection was 6.70, which closely aligned with the predicted value at 97.31% agreement. The storage test showed that the composite color protection could effectively retard the decrease in L*, a*, b* and ΔE values of loquat pulp, while reducing the loss of total sugar, ascorbic acid and total phenol, and the increased of titratable acid content, to maintain the nutrition of the pulp. This study could provide technical reference for the processing and utilization of loquat.

Keywords

• loquat puree
• enzymatic browning
• color protectant
• storage
• color
• nutrition