Storage quick-freezing

A few minutes before starting the dissections, assemble a quick-freezing set up With a hot, fine injection needle puncture several holes at the top part of screw-cap cryotubes. Place these tubes at the top position of metal canes of the type used for storage in liquid nitrogen. Immerse the canes into a liquid nitrogen-filled Dewar flask so that the tubes are held above and cooled by the liquid, but are not immersed in it (see Note 10). 

Fattale et al. [3.46] compared negatively charged liposomes with nanoparticles from poly- (isohexyl-cyanoacrylate), which of both were loaded with ampicillin. Both carriers were of approximately the same size 200 nm but the nanoparticles could be loaded with approx, twenty times more ampicilin. After freeze drying and storage at-4 °C, no ampicillin leaked from the nanoparticles, while it migrated quickly from the liposomes. 

Ethanol s freezing point is much lower than gasoline, though it rises quickly as the water content of ethanol increases. Freezing of ethanol in fuel storage and distribution systems is not a concern. 

For safety, economical storage and shipping, a ai must be quickly irradiated or pasteurized after removal from the tree, then processed into either a powder (by the expensive method of freeze-drying) or a frozen pulp puree. Irradiation and/or pasteurization are required safety procedures to destroy microbes, but also diminish vitamins and other nutrients, which become further reduced by subsequent steps in processing. The reduction of natural a< ai nutrients is evident from the Nutrition Facts panel on many commercial juice products—in most cases showing few if any nutrients. 

---