Emprego de tecnologias emergentes no processamento de suco de laranja adicionado de fruto-oligossacarídeos e suco de laranja produzido via síntese enzimática

Abstract

The aim of this research was to use emerging technologies on the processing of the prebiotic orange juice added of fructo-oligosaccharides (FOS) and in prebiotic orange juice produced by enzymatic synthesis. The first stage of the study was evaluated the effect of atmospheric pressure cold plasma (ACP) and high pressure processing (HPP) on the prebiotic orange juice added 7% commercial FOS. The orange juice was directly and indirectly exposed to plasma discharge at 70 kV with processing times of 15, 30, 45 and 60 seconds. For high pressure processing, the juice containing the same concentration of FOS was treated at 450 bars for 5 minutes. After the treatments, the fructo-oligosaccharides were qualified and quantified by Thin Layer Chromatography (TLC), using densitometer. The organic acids, color analysis and pH values were also evaluated. Both processes did not degrade the FOS. The organic acids and the color of the treated samples were also preserved. On the second stage of the study, the effect of plasma and ozone treatments on prebiotic orange juice produced by enzymatic synthesis were evaluated. The orange juice was directly and indirectly exposed to plasma discharge at 70 kV with processing times of 15, 30, 45 and 60 seconds. For ozone processing, different loads (0.057, 0.128 and 0.230 mg/ O3.mL of juice) were evaluated. After the treatments, the oligosaccharides were quantified by HPLC. The juice pH, color, total phenolic content and total antioxidant activity were also determined. Both processes promoted a partial degradation of the oligosaccharides in the juice. However, the juice maintained an enough amount of oligosaccharides to be classified as a prebiotic food. The other parameters analyzed were preserved. Thus, atmospheric cold plasma and ozone are suitable non-thermal alternatives for prebiotic orange juice treatment.