Ascorbic Acid Retention, Microbial Growth, and Sensory Acceptability of Lettuce Leaves Subjected to Mild Heat Shocks |
| |
Authors: | Marí aa del R.,Moreira ,Alejandra G.,Ponce ,Carlos E.,Del Valle Sara I.,Roura |
| |
Affiliation: | Authors Moreira and Valle are with Grupo de Investigación en Ingeniería en Alimentos, Facultad de Ingeniería, Univ. Nacional de Mar del Plata (UNMDP), Juan B. Justo 4302, CP: 7600, Mar del Plata, Provincia de Buenos Aires, Argentina.;Authors Moreira, Ponce, and Roura are with Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) Buenos Aires, Argentina. |
| |
Abstract: | Heat shocks not only produced a reduction in the initial content of ascorbic acid but also affected the rate of degradation of ascorbic acid during refrigerated storage. Samples treated at higher temperatures presented faster rates of degradation. The heat shocks produced an initial reduction in the counts of mesophilic aerobic microorganisms, with greater reductions associated with the higher shock temperatures. However, high shock temperatures promoted faster microbial growths during storage, probably due to the liberation of nutrients by the disruption of membrane barriers. The sensory attributes of lettuce leaves subjected to heat shocks presented mixed results. Thermal treatments affected the enzymatic activity, reducing browning phenomena, but also caused deleterious effects on surface color and texture of lettuce leaves. Heat shocks of 50°C could be useful for short‐term preservation of minimally processed lettuce, where the high rate of metabolic processes cause great deterioration of fresh products. |
| |
Keywords: | heat shock treatments lettuce ascorbic acid mesophilic bacteria-sensory attributes |
|
|