[6-1130-P] Postharvest/Food Technology and Process Engineering (6th)

[6-1130-P-28] Study on the Characteristics of Micro Wet Milling and Spray Drying of Sea-buckthorn (Hippophae rhamnoides)

*ODGEREL Ulziibat¹, Md.ZOHURUL ISLAM¹, KITAMURA Yutaka², KOKAWA Mito², ODBAYAR Tseyen-Oidov³, SOLONGO Ganbold³ (1. Graduate School of Life and Environmental Sciences, University of Tsukuba, Ibaraki, Japan(Japan), 2. Faculty of Life and Environmental Sciences, University of Tsukuba, Ibaraki, Japan(Japan), 3. School of Industrial Technology, Department of Food Engineering, Main Campus of MUST, Baga Toiruu 34, Sukhbaabatar District, Ulaanbaatar, Mongolia(Mongolia))

Keywords:Sea-buckthorn juice, Micro wet milling, Particle size, Spray drying

Sea-buckthorn (Hippophae rhamnoides) is by far the most widespread of the species in the genus, with the ranges of its eight subspecies extending from the Atlantic coasts of Europe across to Mongolia and China. Sea-buckthorn (SBT) contains different kinds of nutrients and bioactive compounds such as vitamins, carotenoids, flavonoids, polyunsaturated fatty acids, free amino acids, and elemental components. The aim of this study was to produce whole SBT powders by the application of micro-wet milling (MWM) and spray drying (SD) process. MWM was carried out by varying the different feeding rate of the material at 5, 10, 15 mL/min and rotational speed of the milling stone at 10, 20, 30, 40, 50 rpm respectively. Effective MWM was evaluated based on the obtaining minimum particle size of the whole SBT slurry. It was 5.84 µm., which was obtained at 5 mL/min and 50 rpm operation. The antioxidant properties of SBT slurry by MWM showed higher than the commercial SBT juice. The conventional SBT juice contained 10% oil and was difficult to spray-dry without making a good emulsion. However, MWM process successfully produced a better emulsion of SBT slurry. Then it was spray-dried to make stable powder with the combination of maltodextrin as a carrier. The drying parameter was set as inlet temperature of 90, 110, 135°C, the outlet temperature of 55, 70, 88°C, feeding rate of 10 mL/min and atomizing pressure of 2.1 kg/cm². The spray drying successfully produced the whole SBT powder with 65.6% of total recovery (TS base). The obtained powder is going to be analyzed for moisture content, water activity, bulk density, tapped density, particle density, porosity, particle size distributions and microstructure of the particles. Further study will be carried out to apply vacuum spray drying or VSD for the production of whole SBT powder at lower drying temperature and compare with the conventional spray drying. It is expected that combinations of VSD and MWM could be applied industrially for the production of whole SBT powder.