Effect of heat treatment over folate concentration in a b9 naturally bio-enriched yogurt

LAIÑO, J. E.; JUAREZ DEL VALLE, M.; SAVOY DE GIORI, G.; LEBLANC, JEAN GUY

Horco Molle, Tucuman

Jornada; XXIX Jornadas Científicas de la Asociación de Biología de Tucumán; 2012

Asociación de Biología de Tucumán

The aim was to study the effect of heat treatment over folate concentration and its stability in a B9 naturally bio-enriched yogurt. 3 yogurts were elaborated using B9 producing strains: L. bulgaricus CRL863 & CRL871 and S. thermophilus CRL803 & CRL415. After elaboration, they were heated 3 times at 80ºC for 30 min. After treatment, they were stored at 4ºC. It was evaluated: a) folate production; b) acidity (pH); c) protein concentration & d) cellular viability (Log CFU/mL). Results: Highest levels of folate were reached after yogurt elaboration. Yogurt B (CRL871+CRL803+CRL415) showed the highest folate levels (223,53±2,75 µg/L). Generally, pH was about 4.75 and protein concentration ranged 0,17 to 0.24 g/dL. After heat treatment, only yogurt B had the same folate values (about 220 µg/L). pH and protein levels were not modified with heat. Conclusion: from 3 yogurts, only B showed folate values 3 times higher than a commercial yogurt. After heat treatment, folate concentration decreased 40% in yogurts A & C, but remained constant in B. It is possible to elaborate and apply heat treatment to yogurts with the aim to increase the microbiological safety, without loss of vitamin, depending of employed strains.