RESUMEN
The differences in cell wall polysaccharides are considered as a major influencing factor on the texture of plant-based food after cooking. Here, 18 varieties of lotus rhizomes were collected from different regions of China and subjected to analysis, with the aim to identify the key factors that affect the texture of lotus rhizomes after cooking. The texture (hardness) of fresh samples and the samples after thermal treatment for different time periods was examined. The cell wall polysaccharides present in alcohol insoluble residue (AIR) were further subdivided into different fractions, and the composition of monosaccharides in each fraction was analyzed by gas chromatography. We then calculated the sugar ratios to examine the discrepancies in molecular structure among the fractions. Principal component analysis and regression analysis showed that the ratio of chelate-soluble fraction (CSF) to AIR is the major factor affecting the texture of lotus rhizomes after cooking.
Asunto(s)
Culinaria , Lotus/química , Rizoma/química , Pared Celular/química , China , Culinaria/métodos , Etanol/química , Dureza , Ácidos Hexurónicos/análisis , Monosacáridos/análisis , Pectinas/química , Polisacáridos/química , Análisis de Componente Principal , Análisis de Regresión , Rizoma/citologíaRESUMEN
This study aims to investigate the impact of ferulic acid pretreatment on the hardness of Chinese radish after cooking. Radish slices were immersed in ferulic acid solution and distilled water, respectively. The ferulic acid treated samples showed significantly higher hardness (pâ¯<â¯0.05) than the control samples after cooking, and could keep relatively more integrated cell wall structure after cooking at 100⯰C for 30â¯min. Subsequently, we determined the cell wall fraction contents, sugar ratio and molecular weight distribution of different treated samples. Ferulic acid treated groups showed higher percentage of chelate-soluble fraction (CSF) and sugar ratio 1 than the control groups in both fresh and cooked samples. The CSF had two high molecular weight peaks at 7.7â¯min and 8.6â¯min, probably due to the cross-linking with ferulic acid. This research may provide an effective way to decrease the softening of thermally processed fruits and vegetables.
Asunto(s)
Culinaria/métodos , Ácidos Cumáricos/química , Raphanus/química , CalorRESUMEN
The effects of acetic acid pretreatment on the texture of cooked potato slices were investigated in this work. Potato slices were pretreated with acetic acid immersion (AAI), distilled water immersion (DWI), or no immersion (NI). Subsequently, the cell wall material of the pretreated samples was isolated and fractioned to evaluate changes in the monosaccharide content and molar mass (MM), and the hardness and microscopic structure of the potato slices in different pretreatments before and after cooking were determined. The results showed that the highest firmness was obtained with more intact structure of the cell wall for cooked potato slices with AAI pretreatment. Furthermore, the MM and sugar ratio demonstrated that the AAI pretreated potato slices contained a higher content of the small molecular polysaccharides of cell walls, especially in the hemicellulose fraction. This work may provide a reference for potato processing.
Asunto(s)
Ácido Acético/química , Pared Celular/efectos de los fármacos , Polisacáridos/química , Solanum tuberosum/química , Culinaria/métodos , DurezaRESUMEN
Pretreatments such as low temperature blanching and/or calcium soaking affect the cooked texture of vegetal food. In the work, lotus rhizomes (Nelumbo nucifera Gaertn.) were pretreated using the following 4 treatments, blanching at 40°C, blanching at 90°C, soaking in 0.5% CaCl2, and blanching at 40°C followed by immersion in 0.5% CaCl2. Subsequently, the cell wall material of pretreated samples was isolated and fractioned to identify changes in the degree of esterification (DE) and monosaccharide content of each section, and the texture of the lotus rhizomes in different pre-treatments was determined after thermal processing with different time. The results showed that the greatest hardness was obtained after blanching at 40°C in CaCl2, possibly attributing to the formation of a pectate calcium network, which maintains the integrity of cell walls. Furthermore, the content of galactose, rhamnose and arabinose decreased due to the breakage of sugar backbones and subsequent damage to cell walls. Our results may provide a reference for lotus rhizome processing.
Asunto(s)
Calcio/toxicidad , Calor/efectos adversos , Nelumbo/química , Nelumbo/efectos de los fármacos , Rizoma/química , Rizoma/efectos de los fármacos , Antioxidantes/análisis , Antioxidantes/química , Calcio/administración & dosificación , Fenómenos Químicos/efectos de los fármacos , Extractos Vegetales/análisis , Extractos Vegetales/químicaRESUMEN
The effects of postharvest ß-aminobutyric acid (BABA) treatment on fruit firmness, pectin degrading enzymes, cell wall constituents and microstructural alterations of pericarp in sweet cherry fruit were investigated. BABA significantly delayed the decline of fruit firmness and inhibited the increase of membrane permeability and the accumulation of malondialdehyde in cherries. The BABA-treated fruit exhibited significantly higher contents of water-soluble pectin, CDTA-soluble pectin, Na2CO3-soluble pectin, total pectin, cellulose and hemicellulose than the control during storage. Activities of pectin degrading enzymes including polygalacturonase and pectinmethylesterase were markedly reduced by BABA treatment. Observations by scanning electron microscopy showed BABA maintained smooth cuticle and integrated structure of subepidermal cell in sweet cherry. These results suggest that the delay in fruit senescence by BABA may be due to depressed membrane permeability and malondialdehyde content, reduced activities of polygalacturonase and pectinmethylesterase, enhanced cell wall polysaccharides content, and integrated subepidermal cell structure in sweet cherry.