Effect of the Freeze-Drying Process on the Physicochemical and Microbiological Properties of Mexican Kefir Grains
| Autor: | Alicia Águeda Conde-Islas, Galo R. Urrea-García, Denis Cantú-Lozano, Maribel Jiménez-Fernández, Guadalupe Luna-Solano |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: |
0301 basic medicine
Water activity Microorganism Bioengineering kefir grains lcsh:Chemical technology lcsh:Chemistry 03 medical and health sciences chemistry.chemical_compound Freeze-drying operating parameters 0404 agricultural biotechnology Chemical Engineering (miscellaneous) lcsh:TP1-1185 Food science Process Chemistry and Technology Kefir Grain Residual moisture 04 agricultural and veterinary sciences 040401 food science Lactic acid 030104 developmental biology chemistry lcsh:QD1-999 properties freeze-drying probiotic |
| Zdroj: | Processes, Vol 7, Iss 3, p 127 (2019) Processes Volume 7 Issue 3 |
| ISSN: | 2227-9717 |
| Popis: | The purpose of this study was to investigate how the properties of Mexican kefir grains (MKG) are affected by the operating parameters used in the freeze-drying process. The factors investigated were the freezing time (3&ndash 9 h), freezing temperature (&minus 20 to &minus 80 ° C), pressure (0.2&ndash 0.8 mbar), and lyophilization time (5&ndash 20 h). The maximum range of change and one-way analysis of variance showed that lyophilization time and freezing time significant affects (p < 0.05) the response variables, residual moisture content and water activity, and pressure had a significant effect on the color difference and survival rate of probiotic microorganisms. The best drying conditions were a freezing time of 3 h, a freezing temperature of &minus 20 ° C, a pressure of 0.6 mbar, and a lyophilization time of 15 h. Under these conditions, we obtained a product with residual moisture content below 6%, water activity below 0.2, and survival rates above 8.5 log cfu per gram of lactic acid bacteria and above 8.6 log for yeast. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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