Fruit and vegetable purees as cryoprotectants for vacuum freeze-dried fermented milk products

Fresh fermented milk products have a limited shelf life that can be extended by vacuum freeze-drying. Cryoprotectants are used to increase the survival of lactic acid microorganisms during The most effective cryoprotectants those natural origin. Literature offers little information on cryoprotective effects fruit and vegetable purees. Therefore, we aimed evaluate effectiveness purees in increasing freeze-drying storage products. 
 We studied bioyogurt samples containing pumpkin, fig, banana Rational modes freezing were established basis thermal analysis. cryoscopic temperature was determined differential scanning calorimetry. proportion frozen moisture calculated using Nagaoka formula. Standard methods employed sensory characteristics bioyogurts determine their protein, fat, non-fat solids contents, as well titratable acidity microbiological indicators. addition pumpkin puree increased reduced stage total drying time 13 h, depending amount puree. However, sweet fig decreased 0.5–1.5 1.5–3 respectively. Based evaluation freeze-dried bioyogurts, selected formulations with 15% 10% found had higher counts bacteria compared control. In samples, at 4 ± 2°C than 20 2°C. Pumpkin provided best storage.