Effects of ultrafine grinding on physicochemical, functional and surface properties of ginger stem powders

Abstract

BACKGROUND: Ginger stem (GS) is a by-product of ginger processing. It is not directly edible as a feed or food, which leads to it being discarded as waste or burned. Accordingly, it is very important to develop new functional products in the food or feed industry as a result of high nutritional and medicinal values. In the present study, the structures and physicochemical properties of GS powders of different sizes were evaluated after ultrafine grinding by a vibrating mill. RESULTS: The ultrafine powders exhibited a smaller particle size and uniform distribution. Higher values in bulk density (from 1.07 ± 0.06 to 1.62 ± 0.08 g mL −1), oil holding capacity (from 3.427 ± 0.04 to 4.83 ± 0.03 g mL −1), and repose and slide angles (from 42.33 ± 1.52 to 54.36 ± 1.15°and 33.62 ± 0.75 to 47.27 ± 1.34°, respectively) of ultrafine GS powders were exhibited compared to coarse powders. With a reduced particle size, the solubility of ultrafine powders increased significantly (P < 0.05), whereas the water holding and swelling capacities decreased with a reduced particle size and then increased. Fourier transform infrared spectroscopy analysis showed that ultrafine grinding did not damage the main cellular structure of GS powder. The reduction of fiber length and particle size in GS was observed by light microscopy and scanning electron microscopy. The X-ray diffraction patterns demonstrated the crystallinity and the intensity of the peak in superfine GS powders. CONCLUSION: The present study suggests that ultrafine grinding treatments influence the structures and physicochemical properties of GS powders, and such changes would improve the effective utilization of GS in the food or feed industry.

Effect of superfine grinding on the physico‐chemical and antioxidant properties ofCistanche deserticolapowders

“…Table 2 shows the physical properties of the six different powders. The angle of repose and slip increased with the decrease of particle size, which consistent with Ginger stem superfine powder (Zhao et al, 2020). This may be because the bulk density is reduced, which leads to easier cone formation.…”

“…Micronization is a technology to produce various superfine powders, and the mechanical or hydrodynamic force changes the internal cohesion of material to achieve crushing effect (Zhao et al, 2020). Superfine grinding could change the physico‐chemical and enhance the oxidation capacity, solubility, and expansibility of raw stock.…”

Improving the adsorption characteristics and antioxidant activity of oat bran by superfine grinding

“…The peak at 1156 cm −1 is caused by the stretching vibration of hemicellulose and cellulose C–O–C. The broad absorption peak at 1022 cm −1 is the characteristic absorption peak of C–O–C in hemicellulose sugar ring (Zhao, Meng, et al, 2020 ). To sum up, OB contains protein, cellulose, hemicellulose, polyphenols, and other substances, and ultrafine grinding does not damage the nutritional components of OB.…”

Effects of superfine pulverization technology on the morphology, microstructure, and physicochemical properties of Apium graveolens L. root

“…Superfine pulverization aggravated the degree of fragmentation of the structure of AR tissues, and the long‐chain structure of various macromolecules, such as fibers, was broken, resulting in an increase in short chains. The binding force of the powders to grease was weakened, making the separation between the powders and grease easier (Zhao et al, 2020). Therefore, superfine pulverization reduced the OBC of the AR powders.…”

“…2.5.3 | SC test SC was measured in accordance with the method of Zhao et al (2020) with slight modifications. About 0.5 g (m) each of the five kinds of AR powders was put into a 10 ml graduated cylinder.…”