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BACKGROUND: Ginger oleoresin is prone to destruction from air, light and high temperatures and has a limited shelf life if kept improperly. Its viscous and sticky characteristics also make it difficult to handle and utilize. These issues can be solved via microencapsulation. The goal of this research was to evaluate how different wall materials affect the properties of microencapsulated ginger oleoresin powder. RESULTS: Ginger oleoresin microcapsules were developed through spray drying technique using gum acacia (GA) and whey protein isolate (WPI) as wall materials. The characteristics of the obtained powder, including water activity, wettability and encapsulation efficiency, were evaluated, corresponded to values of 0.20, 90.54 s and 84.15% for whey protein isolate‐based ginger oleoresin powder. Whey protein isolate microcapsules also exhibited higher phenolic content (27.26 mg gallic acid equivalents g−1), total flavonoid (2.94 mg quercetin equivalents g−1) and 2,2‐diphenyl‐1‐picrylhydrazyl radical scavenging activity (68.71%) than GA microcapsules. Both WPI‐ and GA‐based oleoresin microcapsules displayed poor flowability, but possessed a metastable amorphous state as indicated by X‐ray diffraction. GA‐encapsulated oleoresin microcapsules showed a significant increase in particle size (1983 nm) compared to WPI oleoresin microcapsules. Fourier transform infrared analysis of the developed oleoresin microcapsules indicated no change in molecular structure except for a variation in peak intensity. CONCLUSION: Whey protein isolate proved to be more efficient in maintaining the physicochemical and antioxidant activity of spray‐dried ginger oleoresin powder. The present study revealed whey protein‐based oleoresin powder could be used as a therapeutic agent in various nutraceutical applications. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The aim of the present study was to design, fabricate, and evaluate a walnut bleaching machine. The machine consists of a feed hopper, rotating drum, motor, reduction gear, belt and pulley system, pump, storage tank, lever, delivery chute, and a control box. The bleaching process is achieved by simultaneous chemical and mechanical action. In order to assess the performance of the machine, acidified sodium chlorite, sodium hypochlorite, and hydrogen peroxide were used as bleaching agents in 2 and 3% concentrations for 5 and 7 min of time. The result of the performance tests showed the significant effects of bleaching agent and bleaching time on all the performance and color parameters with the exception of damaged walnut percentage. Treating inshelled walnuts with 3% sodium hypochlorite +0.2% HCl (T5) for 7 min followed by rinsing in plain water resulted in attractive and bright shell appearance of walnuts. Further, highest bleaching efficiency (94.69%), fully bleached walnut percentages (94.19), and lowest partially bleached walnut percentage (5.47) were recorded when T5 was used as bleaching agent for 7 min in bleacher. Practical applications Dark shell colored and stained walnuts have poor consumer acceptability. In India, crude methods are employed to remove these shell stains, which compromise the shell integrity, thus leading to moisture ingress into kernels. This results in kernel darkening, mold growth, and oxidative rancidity in walnuts. However, for improving the surface appearance, the walnuts after dehulling are required to be processed. Therefore, a walnut bleaching machine was developed and various chemical bleaching agents were investigated to study their effects on surface cleaning of inshelled walnuts. A technology of this nature can be useful to walnut growers and processors. [ABSTRACT FROM AUTHOR]