Ultrasonication as an innovative approach to tailor the apple seed proteins into nanosize: Effect on protein structural and functional properties.

In this study, protein was extracted from the apple seed flour using alkali-acid precipitation method. The main objective of this study was to evaluate the impact of ultrasonication on structural and techno-functional properties of apple seed protein. Both native (N-protein) and ultra-sonicated protein (US-protein) were characterized for size, zeta potential, structure, protein pattern, crystallinity, thermal stability and functional properties. The results revealed that the hydrodynamic diameter of N-protein and US-protein was 1.2 µm and 484 nm while zeta potential was -11 and -19 mV, respectively. Fourier transform infrared-spectroscopy and X-ray diffraction analysis showed change in the conformational characteristics and functional groups of proteins after nano-reduction. SEM revealed change in the surface morphology of protein molecule upon ultrasonication. Differential scanning calorimetry showed decreased denaturation temperature for US-protein compared to N-protein . SDS-PAGE depicted no change in protein pattern upon ultrasonication. Ultrasonicated protein exhibited increased functional properties like emulsification, foaming, hydrophobicity and oil absorbing properties and hence can be efficiently used as functional ingredient in food and nutraceutical industry.

Nanoencapsulation of green tea extract using maltodextrin and its characterisation.

Nano-particles of green tea extract were prepared by ultrasonication, encapsulated in maltodextrin and were subjected to freeze drying to produce nanoencapsulated powders. Different proportions of 30 % solution of maltodextrin and dry tea extract (1:5; 1:10, 1:15) were combined with a small molecule surfactant (Tween 40). Average particle size of 1:5, 1:10, 1:15 based nano-particles were 380.34, 390.26 and 520.45 nm with encapsulation efficiency of 41.27, 45.92 and 57.51% and with negative surface charge of -22.04, -16.40 and -14.91, respectively. Scanning electron microscopy revealed irregular shapes of nanoencapsulated freeze dried powders with variation in appearance. X-ray diffraction patterns showed very low degree of crystanillity after encapsulation. The nanoencapsulated powders showed characteristic bands in infra-red spectra at âˆ¼ 3200, ∼1600 and âˆ¼ 1140 cm1. Nanocapsules displayed controlled release when compared to free green tea extract under simulated intestinal conditions and all the data showed good correlation with zero order kinetics.