16 research outputs found

    Effect of Irradiation on Quality of Vacuum-Packed Spicy Beef Chops

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    To develop an alternative pasteurization process for the spicy beef jerky (SBJ), it was treated with irradiation doses of 0, 0.5, 1.5, 3, 4, 6, and 8 kGy and the sensory attributes, texture properties, drip loss, and the protein biological efficiency were studied. The results showed that lightness, drip loss, and off-odor of SBJ increased, while the hardness, chewiness, gumminess, color preference, and taste of SBJ decreased with the increase in irradiation dose. This tendency was obvious as the irradiation dose increased to 6 kGy and 8 kGy. The possible reason for these quality changes might be due to the free radicals produced by irradiation. This speculation is supported by the decrease of the content of capsanthin and the increase of the content of TBARS of SBJ with the increase in irradiation dose. The plate counts of treated SBJ indicated that 4 kGy was suitable for pasteurization of SBJ

    Exploration of supercritical water gasification of biomass using batch reactor

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    Title from PDF of title page (University of Missouri--Columbia, viewed on May 24, 2012).The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file.Thesis advisor: Dr. William JacobyIncludes bibliographical references."July 2011"[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] The focus of this study is on gasification of a biomass in supercritical water. Vapor mass yield in a batch reactor after 20 minutes in a 700[degrees]C furnace in air and supercritical water for a wide variety of biomass samples showed that the supercritical water enhanced the gasification efficiency, as it participates as both a solvent and a reactant. The heat of combustion and the heat of gasification had good correlation with the oxidation state of the carbon atom in each biomass sample and proved that thermodynamic changes of state are functions of elemental composition (oxidation state of the carbon atom). The gasification efficiency did not correlate with the oxidation state, concluding that biomass gasification efficiencies are similar for all types of biomass. The temperature and residence time are important operating parameters for supercritical water gasification. The vapor yield, gas composition, the carbon and hydrogen balance of supercritical water gasification were functions of gasification temperature, residence time and biomass load (concentration). Nano particle coating of sawdust enhances the vapor yield of sawdust. Supercritical water gasification of biomass at different heating rates showed that the vapor yield was found to depend on the time of heating during the initial period and later the heating rate played the major role. Modeling of thermochemical reactions in a batch reactor was described and used to estimate reaction order and activation energy for supercritical water gasification of ethanol, butanol and algae

    Effect of infrared drying on chemical and microbial properties of Cold‐Hardy grape pomace (Edelweiss and Marquette)

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    Abstract This study aims to add value to a common wine industry waste by preserving bioactive compounds in cold‐hardy grape pomace (GP) and preventing any microbial growth under the proper drying conditions. Effects of infrared (IR) and hot air (HA) drying on the microbial and physicochemical properties such as color, phenolic compounds, and antioxidant activity of white (Edelweiss) and red (Marquette) GP were studied. The IR heating rapidly reduced the moisture content of GP from 55% wet basis (w.b.) to less than 10%, which resulted in a drying time reduction of 71.9% to 80.2% compared to HA drying. There were no significant differences in color parameters among the IR‐ and HA‐dried pomaces (p > .05). The phenolic content of ‘Edelweiss’ pomace was not significantly affected by both IR and HA drying, whereas the phenolic content of ‘Marquette’ pomace was substantially reduced from 274 mg/g dry extract in raw pomace to 127 mg/g dry extract after HA drying and to 141.9 mg/g dry extract after IR drying. Overall, the microbial load on the fresh pomace samples was dramatically reduced by IR heating, with a reduction of more than 99.9% when the pomaces were dried using IR at a temperature higher than 130°C. However, this high temperature of IR led to a significant reduction of DPPH antiradical scavenge activity for ‘Edelweiss’ pomace (p < .05). This study shows that using the IR approach, cold‐hardy ‘Edelweiss’ and ‘Marquette’ grape pomaces can be efficiently dried with the antioxidant activity maintained, which could be used in a variety of food products as a functional ingredient

    Solubility, structural properties, and immunomodulatory activities of rice dreg protein modified with sodium alginate under microwave heating

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    This research aims to investigate the solubility, structural properties, and immunomodulatory of rice dreg protein (RDP) modified with sodium alginate. The modification was done by wet heating assisted with microwave treatment. The solubility, emulsifying properties at pH 2–12, amino acid composition, molecular weight distribution, circular dichroism (CD) spectroscopy, and FTIR spectra of modified RDP were analyzed and discussed. Results showed that Maillard reaction could significantly enhance the solubility and emulsifying capacity of RDP. Further, an animal model for cyclophosphamide‐induced immunodeficiency was designed to evaluate the immunomodulatory effect of modified RDP. It is therefore suggested that modified RDP could improve the immunomodulatory effect of immunosuppressed mice, and the immunomodulation was concentration dependent, being generally enhanced by increased concentrations. This research revealed that glycosylation modification of RDP through Maillard reaction by wet heating assisted with microwave treatment may be successfully applied to improve the physicochemical properties and bioactive benefits of the final product

    Effect of Irradiation on Quality of Vacuum-Packed Spicy Beef Chops

    No full text
    To develop an alternative pasteurization process for the spicy beef jerky (SBJ), it was treated with irradiation doses of 0, 0.5, 1.5, 3, 4, 6, and 8 kGy and the sensory attributes, texture properties, drip loss, and the protein biological efficiency were studied. The results showed that lightness, drip loss, and off-odor of SBJ increased, while the hardness, chewiness, gumminess, color preference, and taste of SBJ decreased with the increase in irradiation dose. This tendency was obvious as the irradiation dose increased to 6 kGy and 8 kGy. The possible reason for these quality changes might be due to the free radicals produced by irradiation. This speculation is supported by the decrease of the content of capsanthin and the increase of the content of TBARS of SBJ with the increase in irradiation dose. The plate counts of treated SBJ indicated that 4 kGy was suitable for pasteurization of SBJ

    Preparation of umami octopeptide with recombined Escherichia coli

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    The taste of umami peptide H-Lys-Gly-Asp-Glu-Glu-Ser-Leu-Ala-OH (LGAGGSLA) is controversial. One possible reason for this controversy is the use of chemically synthesized LGAGGSLA to confirm its taste. To explore other ways to further confirm the flavor of LGAGGSLA, we developed a new strategy to prepare a bio-source peptide by adopting a gene engineering method to express LGAGGSLA in recombinant Escherichia coli. In our previous work, we structured the LGAGGSLA recombinant expression system and optimized the culturing conditions for preparing a fusion protein. However, the fusion protein was not cleaved by enterokinase to obtain LGAGGSLA. Because the cleavage conditions of commercial enterokinase were not specific and recombinant engineered bacteria had the potential to be used in industrial processes, in this addendum, we calculated the mass and volume yields of key processing steps in the preparation of LGAGGSLA, and established a model of cleavage conditions with the cleavage ratio of LGAGGSLA. When the LGAGGSLA was confirmed to show umami taste, it is considered as a new umami or umami enhancer. The gene information of LGAGGSLA should have a great potential in the development of new flavor product and food product containing high umami flavor
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