No abstract

No abstract

No abstract

Carboxymethyl chestnut starch (CMCS) was synthesized by the reaction of chestnut starch and monosodium chloroacetate in an alkali environment. The hydroxyl groups of starch were etherized through carboxymethyl groups, and the crystallinity of starch was reduced after carboxymethylation. As degree of substitution (DS) increased from 0.22 to 0.63, the degree of amyloglucosidase hydrolysis decreased from 37.0 to 1.6%, which was markedly lower than that of native chestnut starch (NCS) (83.2%). The differential scanning calorimetry results revealed the absence of a transition peak in all CMCS samples. CMCS paste showed significant higher light transmittance and freeze‐thaw stability than those of NCS, and had no water release during storage at room temperature. CMCS with middle DS showed higher viscosity than NCS at high shear rate. The results demonstrated that CMCS can be applied in the industrial processing of paste foods and frozen food as a thickening agent. Practical applications Carboxymethylated starch can be used as an alternative thickener in a wide range of industrial applications. However, there is little information on the synthesis and physicochemical properties of carboxymethylated chestnut starch till now. In the present study, the carboxymethylated chestnut starch was synthesized by the optimization of process, and the microstructure, light transmittance, and freeze‐thaw stability of starch were studied. We believe that starch industry can utilize the results of this study in the synthesis and application of this modified starch.

The key technological parameters for the extraction of water-soluble carotenoprotein from carrot root by enzymatic hydrolysis and partial characteristics of carotenoprotein were studied. The extraction yield of carotenoprotein reached 11.99 μg β-carotene equivalent/g fresh weight by adding 50 g of chopped carrot into 100 mL of Span 40 solution (0.1%, w/v) followed by homogenizing, then 1.5 g of cellulase and 0.4 g of pectinase were added to hydrolyze at 40C for 120 min, and the mixture was finally treated with sonication for 40 min. Purification was carried out by ammonium sulfate precipitation, followed by Sephadex G-200 gel chromatography. The molecular weight (MW) of the carotenoprotein was 419 kD and the MWs of subunits were 39, 22 and 15 kD. Stability comparison between water-soluble carotenoprotein and oil-soluble carotenoid indicated that the stabilities of carotenoprotein were better than those of carotenoid (P < 0.001), when exposed to light or heat treatments. PRACTICAL APPLICATIONSAs a kind of natural pigment in plants, carotenoid has many functions, such as antitumor effect, precursor of vitamin A, oxidation resistance and the ability to enhance immune response. Commercial interest of producing carotenoid is increasing too. However, the shelf life of carotenoid achieved by traditional solvent extraction is affected because of bad stability. This paper aimed to extract watersoluble carotenoprotein from carrot by enzymatic hydrolysis, research the biochemical characteristics of carotenoprotein and compare the stability between carotenoid and carotenoprotein. Optimization of the extraction techniques could be considered as a sustainable alternative method to achieve pigment and improve its stability. We believe that pigment industry can utilize the results of this study in their applications.

A new method is proposed to solve the multiple criteria decision making with interacting criteria, where the preference information on alternatives in a fuzzy relation given by the decision maker. On the basis of the decision maker’s preference information, two types of models — the least squares model, the linear programming model — are constructed to determine the capacities and then to select the most desirable alternative. Finally, a numerical example is used to illustrate the validity and practicality of the proposed method.