39 results about "2-Nonenal" patented technology

According to the invention, there is provided null-LOX-1 barley and plant products produced thereof, such as malt manufactured by using barley kernels defective in synthesis of the fatty acid-converting enzyme lipoxygenase-1. Said enzyme accounts for the principal activity related to conversion of linoleic acid into 9-hydroperoxy octadecadienoic acid, a lipoxygenase pathway metabolite, which—through further enzymatic or spontaneous reactions—may lead to the appearance of trans-2-nonenal. The invention enables brewers to produce a beer devoid of detectable trans-2-nonenal-specific off-flavors, even after prolonged storage of the beverage.

An aroma composition comprising a first component selected from the group consisting of 4-hydroxy-2,5-dimethyl-3(2H)furanone, 3-hydroxy-2-methyl-4H-pyran-4-one, 2-ethyl-4-hydroxy-5-methyl-3(2H)furanone, 4-hydroxy-5-methyl-3(2H)furanone, a sulfur-containing analogue of any of the foregoing, and any combination, thereof; a second component selected from the group consisting of 2-furanmethanethiol, 2-methyl-3-furanthiol, 5-methyl-2-furanmethanthiol, and any combination, thereof; and a third component selected from the group consisting of 2-(1-mercaptoethyl)furan, 2-furanethanethiol, bis-(2-furfuryl) disulfide, a furanthiol disulfide, and any combination, thereof. The aroma composition can further include at least one alkylamine or benzylamine and / or a compound selected from the group consisting of hexenol, 1,5-octadien-3-one, methylthiopropionaldehyde, 2,3-diethyl-5-methylpyrazine, (E)-2-nonenal, (E,Z)-2,6-nonadienal, butanoic acid, 2 and 3-methyl butanoic acid, 2-methyl-3-(methyldithio)furan, dimethyltetrasulfide, 4-hydroxy-2-ethyl-5-methyl-3-(2H)furanone, m-cresol, 3-hydroxy-4,5-dimethyl-2-(5H)furanone, and any combination thereof.

The present invention provides a method for preventing or reducing off-flavor in a beverage. Silane-treated silica filter media are synthesized. By contacting the beverage with the silane-treated silica filter, one or more off-flavor substances or off-flavor precursors bind to the silane-treated silica filter media and are removed. Beverages that tend to develop off-flavor upon storage such as alcoholic, fruit, and vegetable beverages, are suitable for the present invention. The present invention provides a method that can reduce the level of off-flavor substances such as trans-2-nonenal, diacetyl, and cis-3-nonenal. The present invention also provides a method that can reduce the level of off-flavor precursors such as linoleic acid. The silica filter media useful for the present method include rice hull ash, oat hull ash, or diatomaceous earth.

The invention relates to a method for preparing 2-nonenal by ozonization with castor methyl oleate as the raw material, ethanol and n-hexane as the solvent, comprising performing ozonization by ventilating O3 / O2 gas mixture after uniformly mixing the raw material and the solvent at the low temperature, slowly dropping aqueous solution of NaHSO3 in ozonides, raising temperature for reductive decomposition, regulating the pH to 9-11 by sodium hydroxide solution, setting the mixture aside for layering, removing the water layer, rinsing the organic phase to neutrality by de-ionized water, adding dilute sulphuric acid for reflux, and recovering solution through reduced pressure distillation, and obtaining the target product, 2-nonenal, through the molecular distillation of the reaction mixture. In the method, no high pressure is needed during the reaction; the solvent of n-hexane can be recovered for repeated use; the mixed solvent system solves the serious corrosion to the devices by using acetic acid as solvent; the method has clean process, environmental protection, safe execution, simple operation and convenient mass production. The separation and purification of the products are simple.

The invention provides a method for analyzing linoleic acid metabolites in the malt saccharifying process. The generation mechanism of trans-2-nonenal is comprehensively and effectively researched, beer aging can be controlled, and the potability of beer is improved. The analyzing method includes the steps that marked dry powder obtained through linoleic acid marked with 13C and standard dry powder obtained through unmarked linoleic acid are respectively and qualitatively detected through a gas chromatograph-mass spectrometer, the result is compared with a database, analysis is carried out, and the different linoleic acid metabolites are obtained. According to the method, precursors for generating the trans-2-nonenal can be obtained through analysis, the generating mechanism of the trans-2-nonenal can be more objectively and comprehensively recognized, and therefore a main processing measure for pertinently improving the oxidation resistance of beer can be achieved.