Spray freeze-drying (SFD) is a comparatively new method of producing biopharmaceutical powder preparations. In this study, Lactobacillus casei (IFO 15883)was spray freeze-dried to obtain a fine probiotic powder. The survival rate of L. casei in the powder after the SFD process was measured using plate agar counting. To improve the survival rate of L. casei during the SFD process, various experimental conditions were carried out. Among five growth media compositions, in Lactobacilli MRS broth with 1% mannose and 0.1% CaCO3, the viability of the freeze-dried powder was not significantly different from that of the initial powder (p>0.05). The most effective air pressure and protective agentduring SFD were 20 kPa and buffered peptone water (BPW), respectively. Scanning electron microscopy (SEM) was applied to estimate the physical structure and properties of the particles. SFD probiotic particles were of various shapes and sizes with porous structures under different SFD conditions. The average diameter of optimized probiotic powder particles with annealing was 24.8 μm. The survival rate of the final SFD probiotic powder under conditions was 97.7%.

In this study, a method to produce a fine volatile powder extracted from shiitake mushrooms using spray freeze-drying (SFD) was investigated. The analysis of the water-soluble aromatic compounds was carried out by headspace solid phase micro-extraction (HS-SPME) coupled withgas chromatography-mass spectrometry (GC-MS). Scanning electron microscopy (SEM) and laser particle size analysis were applied to characterizethe physical structure and size distribution of the SFD-derivedparticles. Eleven key volatile compounds were identified in the extracts of shiitake mushroomspre- and post-SFD. Recoveries of aromatic volatiles ranging from 30.9 - 82.9% were observed in the overall flavor profile results from the powder obtained with SFD. SEM analysis demonstrated that the particles of the aromatic powderwere spherical in nature, having highly porous surfaces andmean diameters of 19.3 μm.

분무건조법으로 용사용 원적외선 세라믹/알루미늄 복합분말을 제조하여 플라즈마 용사법으로 알루미늄 모재에 용사한 후, 미세구조, 결정상, 열충격저항성 그리고 분광복사율을 조사하였다. 분무건조된 복합분말의 입형은 구형으로 34~105μm . 영역에서 높은 복사율을 보였다. 그러나 알루미늄 첨가량이 증가할수록 원적외선 방사특성은 감소하였다. 결과적으로 용사법으로 원적외선 방사특성의 큰 손실 없이 방사체를 제조하기 위해서는 20~30%wt%Al를 첨가하여 복합분말을 제조하는 것이 가장 효율적이라고 판단된다.