RESUMO
The effects of high humidity hot air impingement blanching (HHAIB) over a range of application times (30, 60, 90, and 120â¯s) on drying characteristics, hardness, cell wall pectin fractions contents and nanostructure, as well ultrastructure of apricot were investigated. Results showed that HHAIB reduced drying time and decreased the hardness of apricot by 20.7%-34.5% and 46.57%-71.89%, respectively. The water-soluble pectin (WSP) contents increased after blanching, while the contents of chelate-soluble pectin (CSP) and sodium-carbonate-soluble pectin (NSP) decreased significantly (Pâ¯<â¯0.05). The hardness and drying time were found to correlate inversely with the WSP content, but positively with CSP and NSP contents. Atomic force microscopy (AFM) detection showed the decomposition and degradation of pectin fractions during blanching. Additionally, transmission electron microscopy (TEM) observation indicated that the cell wall structure was degraded and middle lamella integrity was destroyed by blanching.
Assuntos
Parede Celular/química , Conservação de Alimentos/métodos , Pectinas/química , Prunus armeniaca/química , Dessecação , Conservação de Alimentos/instrumentação , Frutas/química , Dureza , Temperatura Alta , Umidade , Água/análiseRESUMO
Prunus cerasifera has a rich resource and a weak utilization rate and its biological functions have been investigated. We found that the contents of total phenol (TP) in leaves and branches of Prunus cerasifera were 117.8 ± 8.8 and 100.04 ± 0.9 mg/g, respectively; the contents of soluble condensed tannin (SCT) were 73.95 ± 0.9 and 78.65 ± 4.1 mg/g, respectively; the structure of SCT containing afzelechin/epiafzelechin, catechin/epicatechin, and atechin/epicatechin as the main units and the SCT from leaves and branches exhibited better anti-tyrosinase and antioxidant activities. This study could clarify Prunus cerasifera condensed tannin resource availability and lay a theoretical foundation for its development as a natural antioxidant and tyrosinase inhibitor.
Assuntos
Antioxidantes , Inibidores Enzimáticos , Monofenol Mono-Oxigenase/antagonistas & inibidores , Folhas de Planta/química , Proantocianidinas , Prunus domestica/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Proantocianidinas/química , Proantocianidinas/isolamento & purificaçãoRESUMO
To establish the water dynamics model for drying process of Angelicae Sinensis Radix, the Weibull distribution model was applied to study the moisture ratio variation curves, and compared the drying rate and drying activation energy with the drying methods of temperature controllable air drying, infrared drying under different temperatures (50, 60, 70 degrees C). The Weibull distribution model could well describe the drying curves, for the moisture ratio vs. drying time profiled of the model showed high correlation (R2 = 0. 994-0. 999). The result proved that the drying process of Angelicae Sinensis Radix belonged to falling-rate drying period. For the drying process, the scale parameter (a) was related to the drying temperature, and decreased as the temperature increases. The shape parameter (ß) for the same drying method, drying temperature had little impact on the shape parameter. The moisture diffusion coefficient increase along with temperature increasing from 0.425 x 10(-9) m2 x s(-1) to 2.260 x 10(-9) m2 x s(-1). The activation energy for moisture diffusion was 68.82, 29.60 kJ x mol(-1) by temperature controllable air drying and infrared drying, respectively. Therefore, the Weibull distribution model can be used to predict the moisture removal of Angelicae Sinensis Radix in the drying process, which is great significance for the drying process of prediction, control and process optimization. The results provide the technical basis for the use of modern drying technology for industrial drying of Angelicae Sinensis Radix.