Improving functional properties of 'Piel de Sapo' melon juice by addition of a Lippia citriodora natural extract and probiotic-type lactic acid bacteria

摘要

Six selected lactic-acid probiotic-type (PT-LAB) bacteria were screened for sensitivity towards a Lippia citrodora extract with reported functional properties (PLX (R)). The effect of pH (6.7 and 5.5) and temperature (35 degrees C and 4 degrees C) on the minimum inhibitory concentrations (MICs) was determined by the microdilution broth assay. PLX (R). MIC values at 4 degrees C were lower than those at 35 degrees C, and at pH 5.5 were generally higher than those at pH 6.7. After storage at 4 degrees C-4 days, both plain "Piel de Sapo" melon juice (MJ) and fortified with PLX (R) (PLX (R) FMJ) at 2500 mu g/mL (maximum sensorial acceptable limit in MJ), maintained the viability of the six PT-LAB bacteria. Additionally, four of these bacteria showed growth potential (delta & 0.5) in MJ and only one of them (Lactobacillus rhamnosus GG) in PLX (R) FMJ. PLX (R) synergistically increased the antioxidant activity of MJ. PLX (R) and PT-LAB are promising ingredients to increase the functional properties of "Piel de Sapo" MJ.