Predictive Modelling Of Temperature And Water Activity (Solutes) On The In Vitro Radial Growth Of Botrytis Cinerea Pers

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Effect of processing on the drying kinetics and functional value of dried apricot

Apricots can be considered as a good source of phenolic compounds, which are beneficial for human health. Microwaves may be an alternative to the conventional sun or hot air drying techniques used to obtain dried apricot. Nevertheless, their impact on the functional compounds must be taken into account if they are to be recommended as an attractive drying option. This work compares the drying kinetics and the change in the organic acids, phenolic compounds and antioxidant activity of dried apricot when using hot air drying and microwave energy. Empirical (linear and Page) equations can be used to model the drying kinetics in air, combined air-microwave and microwave processes. From the obtained results, it can be concluded that the industrial processing of dried apricots may be improved by using microwave energy, as the drying time is considerably reduced, and the obtained fruit had a higher phenolic content, particularly of chlorogenic acid, catequin and epicatequin. Nevertheless, as the contribution of these phenols to antioxidant capacity was not significant, microwave dried samples maintained the same antioxidant capacity as the air-dried ones. When sulphite is added previous to the drying processes, care should be taken with the total phenols and the antioxidant capacity quantified as it may interfere with the results depending on the methodology used. © 2011 Elsevier Ltd.Igual Ramo, M.; García Martínez, EM.; Martín-Esparza, M.; Martínez Navarrete, N. (2012). Effect of processing on the drying kinetics and functional value of dried apricot. Food Research International. 47(2):284-290. doi:10.1016/j.foodres.2011.07.019S28429047

Preservation of dried fruits by modified atmosphere packaging (MAP) in combination with reduced levels of preservatives

Public defense: 1996-01-01 00:00D

Studying And Modelling The Combined Effect Of Temperature And Water Activity On The Growth Rate Of P. Expansum

The effect of solutes, water activity (aw, 0.890–0.980) and temperature (5–25 8C) on the mycelial growth rate of Penicillium expansum was evaluated. The growth rate dropped as the temperature and aw of the medium decreased. NaCl was the solute causing the greatest growth rate reduction, followed by glucose, glycerol and sorbitol. Statistical analysis of the results showed a significant effect of solute, aw, temperature and combinations of two or three of these factors ( P b0.0001). Whatever the solutes and aw values, the initiation of colony growth required an additional day at 15 8C and 5 8C as compared to initiation at 25 8C. Growth models based on the results obtained with sorbitol and glycerol differed only slightly, with R2 values of 97.00% and 97.95%, respectively. The response surfaces of both quadratic polynomial models showed that P. expansum should be able to grow at low aw (0.890) and that growth at 25 8C should be fastest at aw values ranging from 0.960 to 0.980. Both models presented a good fit between predicted and observed values