title: Modeling of combined effects of citral, linalool and beta-pinene used against Saccharomyces cerevisiae in citrus-based beverages subjected to a mild heat treatment.
abstract: The aim of this work was to evaluate the antimicrobial activity of three terpenes (citral, linalool and beta-pinene), in combination with a mild heat treatment (55 degrees C, 15 min). The study has been carried out on an orange based soft drink inoculated using a wild strain of Saccharomyces cerevisiae. The results, expressed as growth/no-growth data, were analyzed with the logistic regression. A model comprising only of significant individual parameters (p < or = 0.05) and describing the relationships between terpene concentrations and the probability of having stable beverages was obtained. When citral and beta-pinene were combined, the citral concentration required to achieve a 50% probability of having stable bottles (P=0.5) dropped from 100.9 microL/L in the absence of beta-pinene to 49.3 microL/L in the presence of 20 microL/L of beta-pinene. The mixture of citral and linalool was less effective, in fact, the same probability (P=0.5) was obtained combining 60 microL/L of linalool with 35.1 microL/L of citral. The addition of 20 microL/L of linalool and beta-pinene reinforced citral bioactivity and the concentration of citral needed to reach P=0.5 fell from 100.9 microL/L in the presence of citral alone to 42.0 microL/L. The presence of both linalool and beta-pinene at a concentration of 40 or 60 microL/L in the absence of citral led to a lower spoilage probability (P=0.58 and P=0.93, respectively). It can be concluded that the antimicrobial potential of the three terpenes alone can be strengthened combining appropriate concentrations of each of them. This study confirmed also the potentiating effect of a mild temperature treatment on the antimicrobial efficacy of the molecules. Neither the thermal treatment alone nor the presence of the terpenes at their maximum concentrations (without thermal treatment) were able to guarantee the microbial stability of the beverages.
authors: Dipartimento di Scienze degli Alimenti, Università degli Studi di Bologna, Sede di Cesena, Piazza G. Goidanich 60, 47023 Cesena, Italy.
authors: Nicoletta
authors: N
authors: Belletti
authors: Sylvain Sado
authors: SS
authors: Kamdem
authors: Giulia
authors: G
authors: Tabanelli
authors: Rosalba
authors: R
authors: Lanciotti
authors: Fausto
authors: F
authors: Gardini
mesh_terms: D000080462:Acyclic Monoterpenes; D000935:Antifungal Agents / Q000494:pharmacology*; D001628:Beverages / Q000382:microbiology*; D000081008:Bicyclic Monoterpenes; D001643:Bridged Bicyclo Compounds / Q000494:pharmacology; D032084:Citrus sinensis; D003257:Consumer Product Safety; D004338:Drug Combinations; D004357:Drug Synergism; D005519:Food Preservation / Q000379:methods*; D006358:Hot Temperature; D016015:Logistic Models; D039821:Monoterpenes / Q000494:pharmacology; D012441:Saccharomyces cerevisiae / Q000187:drug effects* / Q000254:growth & development
chemical_list: D000080462:Acyclic Monoterpenes; D000935:Antifungal Agents; D000081008:Bicyclic Monoterpenes; D001643:Bridged Bicyclo Compounds; D004338:Drug Combinations; D039821:Monoterpenes; C010789:beta-pinene; C018584:linalool; C007076:citral