Abstract: As a new type of food-grade Pickering particles，solid lipid particles （SLPs） draw wide attention due to their good bioavailability，safety，wide sources and high industrialization prospects.Controlling the size and morphology of SLPs is of great significance for the preparation of stable SLPs Pickering emulsion.This paper took high-melting-point solid fat-fully hydrogenated soybean oil （FHSO）as the research object and Tween 40 （T40） as emulsifier.SLPs with different particle size，crystal forms and morphologies were prepared with different ultrasonic power （300，350，400 and 450 W） and time （1，2，4，and 6 min）.The influence of SLPs on emulsion droplet size was studied.The results show that SLPs without T40 is wide stip-like with the average particle size（Z-average） of 1.6~2.9μm，and the crystal form is α-form；SLPs containing T40 is rod-like and with spherical shape，its Z-average is 259~480 nm，and the α-form and β-form crystals coexist.When the ultrasonic time is 4 min，Z-average of SLPs without T40 increase with the increase of ultrasonic power，with no obvious change in the crystal form and morphology，whereas Z-average of SLPs containing T40 increase gradually，and β-form and spherical crystals increased.When the ultrasonic power is 350 W，Z-average of SLPs without T40 decrease with the increase of ultrasonic time，with no obvious change in the crystal form and morphology，whereas Z-average of SLPs without T40 decrease significantly （from 480 nm to 261nm），but the morphology and crystal form does not change significantly.It can be concluded that the addition of T40 reduces the particle size of SLPs，changes the crystal form of SLPs，and promotes the transformation of the crystal morphology from plate-like to rod-like and spherical.For the emulsions prepared with the above SLPs，it is found that the emulsions containing SLPs without T40 are unstable and massive flocs appears on the upper layer；while stable white emulsions were obtained with the SLPs containing T40，and the emulsion particle size changes with the SLPs particle sizes，polymorphs and morphologies.

Key words: solid lipid particle, ultrasonic, particle size, morphology, crystal form, emulsion