Potential Use of Aloe Vera (Aloe barbadensis Miller) Leaf Gel in the Development of Functional Ice Cream: Physicochemical, Bioactive, Thermal, Rheological, and Sensory Properties

Abstract

Aloe vera leaf contains a transparent mucilaginous gel possessing notable chemical, pharmacological, biological, and therapeutic activities. The unique structure and colloidal composition of ice cream make it a highly suitable medium for the efficient delivery of bioactive compounds, as well as its ability to be stored at low temperatures. This study investigated the effects of different proportions of aloe vera leaf gel (AVLG,1 g/100 g and 2 g/100 g) on the physicochemical, rheological, total phenolic content (TPC), thermal, and sensory characteristics of ice creams, formulated with and without an emulsifier, in comparison to reference samples. The findings revealed that the pH values of the samples were nearly neutral, ranging from 6.55 to 6.61. The incorporation of AVLG, with or without an emulsifier, increased both dry matter content from 33.09% (control) to 40.57% (A2E2), and TPC values, from 0.073 (control) to 0.099 mg GAE/g (A1E2). Additionally, the AVLG supplementation played a significant role in altering the color features of the enriched samples compared to the reference sample, with L* values ranging from 82.37 to 86.01, a* values from-2.25 to-2.86, b* values from 1.96 to 4.97, and Delta E* values from 3.19 to 4.73. The thermal analysis indicated that enriching the samples with AVLG, with or without an emulsifier, reduced the Delta Hm from 160.80 to 53.60 J g-1. The steady-state shear data of ice cream mixtures, which exhibited pseudoplastic flow characteristics, were accurately described by the Ostwald de Waele model (R2>0.9974), with ice cream consistency coefficient values of 0.25-0.68 Pa.s, flow behavior index values of 0.50-0.80, and apparent viscosity values of 0.0980-0.1540 Pa.s. The sensory evaluation results showed that there were no statistically notable differences in sensory perception among the evaluated samples. Overall, the findings highlighted that AVLG can serve as a functional ingredient and natural colorant in ice cream production, offering various advantages.