Preparation of fat substitute based on the high-methoxyl pectin of citrus and application in moon-cake skin

Abstract

The high-methoxyl pectin of citrus was used to prepare a fat substitute and applied to the processing technology of moon-cake skin. The physical, chemical, and sensory properties of fat substitutes and prepared moon-cake skins were studied by selecting texture properties, rheological properties, water distribution, and water-holding capacity. Results showed that the gel hardness of glucan–sucrose (G-SG) (glucan/sucrose = 4:6) as synergistic gel was 6.23 ± 0.10 N, the elasticity was 3.97 ± 0.03 mm, the adhesive viscosity was 4.87 ± 0.20 N, the chewiness was 16.87 ± 0.51 mj, the water-holding capacity was 98.33%, and the gel obtained from sucrose (SG) as gelation agent had no significant difference (P > 0.05). The consistency coefficient and thixotropic circle area of G-SG was larger than that of SG. Through dynamic viscoelastic scanning, we found that the tanδ of G-SG was smaller, and it had stronger hydrophobic interaction and stronger fluid properties after high-speed shear. It also more easily maintained a flow state similar to oil. G-SG was further applied to the processing technology of low-fat moon-cake skin. The color of the prepared low-fat moon-cake skin darkened, the water-holding capacity was enhanced, the fat content decreased from 22.21% ± 0.54% to 14.07% ± 0.57%, the oil droplets enlarged, and flocculation strengthened. Results of texture-characteristic and sensory-score analyses showed no significant difference (P > 0.05) from the control group when the oil substitution amount was 40%. At this time, the total sensory score was 41.71 ± 2.02.