The effect of freeze-thaw cycling on the chemical composition of aqueous solutions of organic substances

By means of spectrophotometry and chemical analysis, it was found that multiply repeated freezing-thawing cycles for aqueous solutions of carbohydrates, choline chloride, and diphenylpicrylhydrazyl (DPPH) alter the chemical composition of the final solutions. The DPPH decay detected during the repetition of this treatment suggests that the degradation of organic molecules involves the stage of formation of free radicals. It was assumed that the cause of the observed processes is cavitation.