Advanced Materials Research Vols. 554-556

Abstract: In this article, investigation on the effect of microwave treatment on the catalysis of papain had been carried out. According to the results, the thermal effect was found to be the main factor to cause inactivation of enzyme. The kinetic parameters and the fluorescence spectroscopy implied that the microwave processing had changed the conformation of the enzyme molecules and thus affected its activity. The results also showed that the microwave treatment had not changed the optimum pH value of the enzyme catalysis, and the inactivation rate of the enzyme was inversely proportional to the concentration of the enzyme. In addition, a certain concentration of the disodium EDTA media had been found to effectively protect the enzyme activity in microwave processing.

Abstract: This paper investigated main compositions, water-holding capacity and oil-absorbing capacity of ginkgo protein. Experimental results showed that ginkgo protein contained 80.36 percents of protein which can meet the functional requirements of food and possessed excellent oil-absorbing capacity and water-holding capacity which was beneficial to flour absorbing oil and holding water. Ginkgo protein was added into flour to make dough with different ginkgo protein content. Experimental data showed that ginkgo protein enhanced the dough opaque property and boosted the dough tensile property. Therefore, adding appropriate amount of ginkgo protein can improve the dough rheological performances.

Abstract: The proper fertilizer placement is an important technical measure to reduce fertilizer waste and increase the yield of summer maize. Fertilizer application into the area where root system density is higher and root activity is relatively large, which would accelerate the uptake rate and increase uptake quantity of nutrient of maize, improve the yield of summer maize. Appling quick-acting nitrogen fertilizer in the bottom of the maize seed is easy to cause the phenomenon of burn seedlings. But coated nitrogen fertilizer can slowly release nitrogen and will not harm the germination of maize seed, so it may be feasible to apply coated nitrogen fertilizer in the bottom of the maize seed. A field experiment is designed to study the effect on summer maize early growth and nutrient uptake by coated nitrogen fertilizer placement and the result shows that the nutrients diffusion area of coated nitrogen fertilizer is relative small, and applying the fertilizer below can centralize the nutrients around the area where root system is dense, promote the growth of maize‘s root system and increase maize’s uptake of nitrogen.

Abstract: Chicken breast which used in present study were coated with dipping solution contained ordinary cornstarch, waxy cornstarch, and modified cornstarch in order to improve the crispness of crust during microwave-reheating process. A physical characteristics assessment (such as water and oil content, color and texture analysis) and sensory evaluation of microwave-reheating popcorn chicken which manufacture with different kinds of cornstarch were determined. The results showed that samples which made with modified cornstarch had the best improvement on crispness (P < 0.05), although ordinary cornstarch and waxy cornstarch batters exhibited crispy crust texture. Moreover, the lowest water molecule migration during microwave-reheating was found in samples with modified cornstarch-added dipping solution, which was consistent with the highest sensory overall acceptability scores (P < 0.05). It revealed that compared with ordinary cornstarch and waxy cornstarch, modified cornstarch had the best effect on the quality characteristics of microwave-reheating popcorn chicken.

Abstract: The paper studied the effect of kiwifruit protease on tenderization of pork and related characterization has been made, the result indicates that pork marinate with kiwifruit protease may lead the degradation of collagen protein and the change of the myofibril fragmentation index (MFI), particle size, viscosity, Warner-Bratzler shear force, area force versus time (Area F-T) as well as microstructure characteristics. Because of the inconvenience of characterization of MFI and soluble collagen, viscosity, particle size analysis, shear force and area F-T can fast and accurate characteristic the changes of tenderizer of pork after marination with kiwifruit protease.

Abstract: The glycation of soy protein isolates and maltodextrin by Maillard wet-heating were evaluated. Glycosylating condition was optimized by the single factor test. The effects of temperature, heating time, protein content, weight ratio of maltodextrin to protein and dextrose equivalents (DE) of maltodextrins (Mds) on the degree of substitution (DS) and browning were investigated. The most optimum conditions are as follows: temperature 90°C, heating time 3h, the protein content 10mg/mL, the weight ratio 2, DE of maltodextrins 9~12. The degree of substitution and browning reaches 14.9% and 0.27 respectively. The aim of this work was to investigate the relationship between the conditions and the degree on the glycation of SPI and Mds.

Abstract: In order to understand Preservation effect on Brassica napus by MSOD, different concentrations of poly-aspartic manganese (II), ferrous cysteine, copper glycine are sprayed to Brassica napus, activity changes in SOD and POD and changes of MDA content are inspected. The results showed that for Brassica napus sprayed with MSOD, it makes preservation effect higher and storage period longer.

Abstract: The quadratic orthogonal rotation design with 3 factors was used to study the effect of sodium hypochlorite, sodium sorbate and calcium propionate solutions on the chestnut, and to establish the function model with 3 factors. The analysis on this model showed that the order of the effect of 3 factors was as follows: Calcium propionate > Sodium sorbate >Sodium hypochlorite; In this test, for getting over 55% good-fruit rate, respectively, the optimum sodium hypochlorite concentration was 11.4％－19.5％, sodium sorbate concentration was 2.67％－39.9％, calcium propionate concentration was 1.09％－2.71％.

Abstract: The effects of heat treatment on the changes in the protein components and size distribution of bovine milk fat globules were investigated. The results of sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) showed that some membrane proteins, such as xanthine oxidase and butyrophilin, had disappeared or were weakly stained in the gel due to heating of milk. The volume surface average diameter of raw milk fat globules ranged from 1.15 to 7.42 μm. When the heating temperature was above 90 °C or the heating time was prolonged above 10 min, the average diameters of heated milk fat globules increased significantly (P < 0.05).

Abstract: The pH-shifting processes (include acid and alkali process) and conventional water-wash process was applied to recover protein from bony silver carp muscle. And the new process was evaluated to obtain proteins for low salt (0% and 1% NaCl, w/w) fish products. The alkali isolated protein (AK) exhibited the best solubility at all salt concentrations. Furthermore, the AK had the highest gel strength and water binding capacity at low salt concentrations (0% and 1%). Low salt products of AK containing 1% salt showed similar mechanical properties to the water wash surimi (WM) obtained with 2% salt. The results obtained showed that the alkali process is a good method to recover functional proteins from boney silver carp muscle for low salt fish products.