Stability of monosodium glutamate in green table olives and pickled cucumbers as a function of packing conditions and storage time.
The effects of different packing conditions and storage times on the stability of monosodium glutamate (MSG) added to two different fermented vegetables (Spanish-type green table olives and pickled cucumbers) were studied. Factors such as packaging material (glass bottle versus plastic pouch), heat treatment (pasteurisation versus non-pasteurisation), and the presence or not of a preservative compound (potassium sorbate) were considered. The MSG content of pickled cucumbers was stable for up to 1 year of storage in all packing conditions studied. The MSG content also remained stable in pasteurised green table olives. On the contrary, MSG was extensively degraded (>75% degradation) after 54 weeks of storage in unpasteurised green olives with a higher degradation rate in glass bottles compared with plastic pouches. In the presence of potassium sorbate, MSG was also considerably degraded in olives packed in plastic pouches (>50% degradation), but hardly degraded in glass bottles. The results indicate that MSG degradation in olives is due to the action of both lactic acid bacteria and yeasts, with the formation of γ-aminobutyric acid as the major end-product.
a Food Biotechnology Department , Instituto de la Grasa (C.S.I.C.) , Seville , Spain.
Antonio
A
de Castro
Antonio Higinio
AH
Sánchez
Víctor Manuel
VM
Beato
Francisco Javier
FJ
Casado
Alfredo
A
Montaño
D018553:Cucumis sativus / Q000737:chemistry*; D005285:Fermentation; D005421:Flavoring Agents / Q000032:analysis*; D005516:Food Microbiology; D018857:Food Packaging; D005519:Food Preservation; D005520:Food Preservatives; D061353:Food Storage; D031658:Olea / Q000737:chemistry*; D012970:Sodium Glutamate / Q000032:analysis*; D013997:Time Factors
D005421:Flavoring Agents; D005520:Food Preservatives; D012970:Sodium Glutamate
cucumbers; degradation; glutamate; pyroglutamic acid; table olives; γ-aminobutyric acid