Evaluation of Antioxidant Properties of Native Utah Berries and Their Potential for Use in Meats

In industry, antioxidants are added to prevent changes that affect quality due to oxidation, such as the development of off flavors, unacceptable odors and discoloration. New resources that are familiar to consumers and may work as antioxidants should be studied. The changes in antioxidant activity were determined for four freeze-dried native wild berry powder species in Utah, including skunkbush (Rhus trilobata), chokecherry (Prunus virginiana), river hawthorn (Crataegus douglasii) and silver buffaloberry (Shepherdia argentea), during cold storage (-20 °C) for 6 months. The total antioxidant activity was stable in most of the berry powders during the six months of frozen storage. Overall the river hawthorn and buffaloberry contained the highest antioxidant activity values, which indicated that they would be more efficient for use as food antioxidants. The effectiveness of two different levels of native Utah river hawthorn and buffaloberry freeze-dried powders in maintaining the quality of ground poultry and ground beef was studied. Meat patties mixed with berry powders were held at 4 °C and analyzed every three days for two weeks. The river hawthorn berry and silver buffaloberry delayed the undesirable changes in flavor or color caused by the oxygen present in the air in both chicken and beef ground patties. However, the plant pigments in the silver buffaloberry increased the redness of chicken patties. Neither berry significantly changed the color of ground beef patties or changed the microbial growth in ground meats. Overall, both river hawthorn and buffaloberry are suitable for using in ground beef product as antioxidants. Milk mineral and sodium tripolyphosphate are antioxidants that could bind free metal ions into insoluble or inactive forms. They can delay the changes of the meat pigment and maintain color in meat products. The purpose of the third study was to examine the effect antioxidants on meat pigment.pH describes the amounts of acid in food. Slowed color changes in the poultry meat pigment with antioxidants was seen both at the pH of living poultry muscle (7.2) and the pH of raw poultry meat (pH 6.0). This suggested that addition of metal-binding antioxidants like milk mineral or sodium tripolyphosphate could help preserve poultry meat pigment and maintain the color of poultry products

Isolation and Purification of Anthocyanins from Black Bean Wastewater Using Macroporous Resins

Isolation and purification of anthocyanins from black bean canning wastewater by column chromatography with macroporous resins were investigated in this study. Different adsorption materials and adsorption conditions were compared and the most effective material and adsorption conditions were selected to purify anthocyanins. Purified anthocyanins then were identified by high performance liquid chromatography electrospray tandem mass spectrometry. The most effective macroporous resin was selected by comparing the adsorption performance of five different types of macroporous resins (Diaion Hp20, Sepabeads Sp70, Sepabeads Sp207, Sepabeads Sp700, and Sepabeads Sp710). Equilibrium adsorption isotherms of five resins with wastewater were measured and analyzed using Langmuir and Freundlich isotherm models. Both Langmuir and Freundlich models could describe the adsorption process. The adsorption and desorption behaviors of anthocyanins were studied using a dynamic method on the five types of resins, and Sp700 presented the highest adsorption capacity as well as desorption capacity, indicating that Sp700 is a good candidate for purification of anthocyanins from black bean canning wastewater. The most effective adsorption conditions were tested using Sp700. Dynamic adsorption and desorption were performed in glass columns packed with Sepabead Sp700 to optimize the purification process. Temperature during adsorption and desorption (25°C and 35°C) did not significantly affect the adsorption and desorption ratio. Adsorption ratio was significantly reduced when the flow rate increased from 1.5 mL/min to 2.5 mL/min. However, desorption ratio was not affected by flow rate (from 1.5mL/min to 0.3mL/min). Ethanol concentration (from 30% to 60%) did not affect desorption ratio. Four kinds of anthocyanins were identified in black bean canning wastewater. The major anthocyanins were delphinidin 3-glucoside, petunidin 3-glucoside, and maldvidin 3-glucoside, with a small amount of petunidin 3, 5-diglucoside also in the final product

论道德的经济价值

Abstract in Chinese: 道德作为特殊的生产性资源具有独特的经济价值，不仅体现在创造使用价值的过程中，也体现在创造价值的过程中。现代企业的经营实践，全面印证了道德与现代经济的这种正向价值关联。但道德所具有的经济价值有其合理限度，应在复杂的经济关系中去理解、分析和利用道德的经济作用。Abstract in English: As a special productive resource, morality has unique economic significance that is displayed in the process of production not only of use-value, but also of value. This positive value correlation has long been confirmed by the management practice of modern enterprises. The economic value of morality has, however, a rational limit; its eco-nomic role should be understood, analyzed and utilized in complex economic relations. [pp.301-302

Investigation into Constitutive Equation and Hot Compression Deformation Behavior of 6061 Al Alloy

Hot compression tests of 6061 Al alloy were applied under the Gleeble-3500 system at temperature range of 300 – 450 °C and strain rate range of 0.01-10 s−1. The true stress-strain curves of 6061 Al alloy were acquired and the flow stress was recorded and corrected. The associated microstructure of 6061 Al alloy after hot deformation process was observed. The results suggest that the stress level of 6061 Al alloy during hot compression process decreases with increasing compression temperature and decreasing strain rate. Arrhenius equation and the Zener-Hollomon parameter in the hyperbolic sine-type equation were utilized in present research to formulate the constitutive equation of 6061 Al alloy. The microstructure after hot deformation consists of elongated grains and the dynamic recovery of 6061 Al alloy occurs during hot compression. However, for the alloy deformed at low Z value, the existence of newly refined grains around the serrated grain boundaries indicates the occurrence of partial dynamic recrystallization

Mutual effects between Pinus armandii and broadleaf litter during mixed decomposition

Mixed-decomposition effects are commonly observed in natural and planted forests and affect nutrient cycling in a forest ecosystem. However, how one litter type affects the decomposition of another is still poorly understood. In this study, Pinus armandii litter was mixed with Betula albosinensis, Catalpa fargesii, Populus purdomii, Eucommia ulmoides, and Acer tsinglingense litter. The mixtures were placed in litterbags and buried in soil with consistent moisture for a 180-day indoor simulated decomposition experiment. The litterbags were periodically harvested during decomposition; the litter residues of different species were separated, and the biomass dynamics of each litter type were simulated. In addition, the soil sucrase, cellulase and polyphenol oxidase activities were also detected three times. The mutual effects of needle and broadleaf litter during mixed decomposition and the possible underlying mechanisms were investigated. The results indicated that (i) during the decomposition experiment, P. armandii needles significantly inhibited the decomposition of broadleaf litter in the first 3 months, while the broadleaf litter accelerated the decomposition of P. armandii needles in only approximately 40% of the cases. However, the inhibitory effects of needles on broadleaf litter decomposition subsequently exhibited significant weakening, while the accelerating effects of broadleaf litter were significantly enhanced. The effects of mixed decomposition on the activities of three enzymes can only partially explain the interactions between different litter types; (ii) the prediction by the decomposition model showed that most of the broadleaf litter types could continuously accelerate the decomposition of P. armandii needles throughout the mixed decomposition process, while the decomposition of broadleaf litter would be significantly inhibited at least in the short term. In general, four of the five broadleaf litter types (excluding E. ulmoides) could accelerate the early decomposition of P. armandii needles and consequently accelerate nutrient cycling in P. armandii pure forests. These species could be used for the transformation of pure P. armandii pure forests to mixed forests