The collapse temperature (Tc) and the glass transition temperature of freeze-concentrated solutions (Tg') as well as the crystallization behavior of excipients are important physicochemical characteristics which guide the cycle development in freeze-drying. The most frequently used methods to determine these values are differential scanning calorimetry (DSC) and freeze-drying microscopy (FDM). ...

BACKGROUND Freeze-drying sperm has been developed as a new preservation method where liquid nitrogen is no longer necessary. An advantage of freeze-drying sperm is that it can be stored at 4 °C and transported at room temperature. Although the successful freeze-drying of sperm has been reported in a number of animals, the possibility of long-term preservation using this method has not yet been ...

Freeze-drying has been considered as a good technique to improve the long-term stability of colloidal nanoparticles. The poor stability in an aqueous medium of these systems forms a real barrier against the clinical use of nanoparticles. This article reviews the state of the art of freeze-drying nanoparticles. It discusses the most important parameters that influence the success of freeze-dryin...

ABSTRACT: In this study, response surface methodology was used to optimize ultrasound osmotic pretreatment with finished freeze drying of black cherries. Freeze drying is a separation process based on the  sublimation phenomenon. This process has the following advantages as compared to the conventional drying process, maintenance of the structure, moisture removal at low temperature (reduced tr...

The effects of drying time during freeze-drying on the outermost cell surface of an encapsulated strain of Staphylococcus aureus S-7 (Smith, diffuse) were investigated, with special attention paid to capsule and slime production. To quantify capsule and slime production, capsule antigen production and cellular characteristics such as growth type in serum-soft agar, cell volume index, and clumpi...

BACKGROUND Although mouse spermatozoa can be freeze-dried without losing their reproductive capacity, the technique needs further improvements to reduce the incidence of chromosomal damage to spermatozoa. Effects of freeze-drying on human spermatozoa are unknown. METHODS Mouse spermatozoa were suspended in a Tris-buffered EGTA solution briefly (10 min at 37 degrees C) or for 1-7 days at 4 deg...

in this study, the effect of edible coat (carboxy methyl cellulose) before osmotic dehydration anddifferent drying methods on sensory and physical properties of dried apple (v. golden delicious)rings was investigated. the coated and non-coated samples pretreated with 50% sucrose osmoticsolution and dried in freeze drier (-40 to -50°c, 0.026-0.017 mbar, 24 hr), vacuum drier (70°c, 200mbar, 8-10 ...

In the present work the textural properties of mushroom and onion, fresh and after freeze-drying, were studied, to understand how this drying treatment influences the texture of these food products. The fresh products had average moisture contents of 90.25 % and 90.02 % (wet basis) and the freeze-dried ones had moisture contents of 7.01 % and 5.19 % (wet basis), for mushroom and onion, respecti...

A novel time-saving and cost-effective release technique has been developed and is described. The physical nature of the process is explained in combination with experimental observations. The results of the flash release process are compared with those of freeze-drying and supercritical CO2 releasing. It is demonstrated that the new technique is not only simpler but it also gives better yield ...

Turgor-mediated leaf movements of the legume Samanea saman are associated with the migration of K(+) and Cl(-) between opposing sides of the motor organs (pulvini). We have investigated the pathway of this ion migration by localizing K(+) and Cl(-) within the secondary pulvinus at various times during leaf movements. Ion distributions in freeze-dried cryosections of pulvini were determined by s...