Application of microwave heating in the production of homogeneous paste from the fruits of small-fruited apple trees

Abstract

The paper presents data on the chemical, physical and microbiological changes during storage of paste from the fruits of small-fruited apple trees processed with microwaves. After six month of storage the content of water soluble solids increased 1.02 times (from 21.50 % to 21.93 %). The sugar-acid index decreased 1.23 times (from 10.25 % to 8.35 %); the titratable acidity increased 1.13 times (from 9.92 g/dm3 to 11.21 g/dm3). The mass fraction of pectin substances decreased 2.51 times (from 2.31 % to 0.92 %) and the content of Vitamin C decreased 1.26 times (from 24.1 mg/100 g to 19.12 mg/100 g). The number of mesophilic aerobic and facultative anaerobic microorganisms did not exceed 200 colony-forming units (CFU) per gram. The number of yeasts did not exceed 260 CFU/g and the number of filamentous fungi did not exceed 620 CFU/g. No pathogenic or facultative pathogenic bacteria were found during all the period of storage.