777 results about "Food sample" patented technology

The present invention relates to a method for determining the presence or absence of contaminating bacteria in a packaged food sample comprising storing food in a package having as a lining a hydrophilic polymeric composition, said composition preferably being permeable to water and at least one gas dissolved in water or water vapor and being selected from the group consisting of carbon dioxide, carbon monoxide, hydrogen sulfide, sulfur dioxide, hydrogen and ammonia gas and containing an indicator for detecting the presence or abscence of said gas; said indicator being polymerized or dispersed throughout said polymeric composition or coated onto a hydrophobic polymeric composition.

A consumer food testing device for testing for the presence of harmful contaminants in a food sample, includes a system for producing a visual cue upon detection of a harmful chemical, biological, and / or ionizing radiation contaminant; and a processing system responsive to the detection of a harmful contaminant, for transmitting the global position of the consumer testing device, the identity of the harmful contaminant, and the time and date to a remote monitoring facility.

An ultrasonic field-portable system for accurately measuring hematocrit (HCT) and hemoglobin concentration (HGB) in small food samples. The system includes an analyzer (10) that allows extremely accurate measurements of blood hematocrit from only one or two drops of +>>d collected in a disposable sampling device (12) that is then inserted into the analyzer (10). The system is compact enough to package into a point of care device, making it a point of care device with accuracy comparable to larger CBC lab equipment.

The invention discloses a solution separation preparation device for security detection on a blocky food sample. The solution separation preparation device comprises a food solution preparation tank,crushing blades, a water supply tank, a rotating shaft and a stirring centrifugal cylinder, wherein the bottom of the food solution preparation tank is fixed on a rack; a sealed inner cylinder is mounted inside the water supply tank; a water storage cavity of an annular structure is formed outside the sealed inner cylinder inside the water supply tank; a rotating shaft is arranged in the middle ofthe sealed inner cylinder inside the water supply tank in a vertical penetration manner; a plurality of crushing blades are mounted at the lower part of the rotating shaft; and a driven gear ring isconnected with the upper end of the stirring centrifugal cylinder. The solution separation preparation device is convenient and rapid to assemble, the crushing blades are rotated to crush a blocky food sample placed inside the crushing cavity, the crushed blocky food sample is mixed with water inside the crushing cavity, then a food sample solution is prepared, components to be detected in the blocky food sample can be conveniently separated out, centrifugal treatment is achieved through the stirring centrifugal cylinder, good stability is achieved, and convenience is brought to further detection treatment.

The present invention is directed to a method and apparatus that satisfies the need for a bioelectronic tongue for food allergy detection. The method of detecting concentration of food allergen incorporates antibodies into an electronic tongue to create a bioelectronic tongue. Additionally the method uses impedance, capacitance, and / or other related electrochemical methods for detecting analyte in complex media. Furthermore the method additionally includes methods to subtract out non-specific interactions. The method also subtracts non-specific interactions. The device / apparatus is a Bioelectronic Tongue for detecting allergen in diluted food samples. The device includes: a sensor array; an impedance or capacitance analyzer; a preprocessor; a feature extractor; a pattern recognizer; and an output device indicating an allergen concentration. In order to implement the method of detecting food allergens on a bioelectronic tongue a computer readable medium containing an executable program is used for performing the analysis of a food sample. The executable program performs the acts of: preprocessing data from an impedance analyzer; extracting a feature pattern; recognizing a pattern of features of data representing a concentration of food allergen contained is the food sample; and outputs allergen concentration data.

A method for detecting an ingredient in a food product includes establishing a spectral signature in a Raman spectrum obtained from a chemical substance; allowing a food sample solution obtained from a food product to come to contact with a first nano-scale surface structure in a first sensor, wherein the first sensor comprises a substrate, wherein the nano-scale surface structure comprises a plurality of columns over the substrate or a plurality of holes in the substrate; illuminating the food sample solution and the first nano-scale surface structure on the first sensor by a laser beam; scattering the laser beam by the food sample solution and the first nano-scale surface structure to produce a scattered light; obtaining a first Raman spectrum from the scattered light using a spectral analyzer; and identifying the spectral signature in the first Raman spectrum to determine the existence of the chemical substance in the food product.

A molecular imprinting polymer of a pyrethroid insecticide is characterized in that the polymer is prepared by the following steps: a. a pyrethroid template molecule, a functional monomer for polymerization, a cross-linker and a pore-forming agent are mixed; b. the substances are arranged in a closed container after being uniformly mixed, the pure nitrogen aeration is used for removing the oxygen, the in-situ polymerization is carried out by adopting the thermal-initiation or the photo-initiation mode after the closing, thus generating the molecular imprinting polymer; c. the molecular imprinting polymer is ground, mixed liquid of organic solvent and acid is utilized for removing the template molecule; d. and the molecular imprinting polymer which is obtained in step c is dried in the vacuum condition. The invention further discloses an application of the polymer, compared with the prior art, the molecular imprinting polymer has the advantages that: the preparation process is simple, the operatability is strong and the preparation cost is low; the prepared polymer has good selectivity and high enrichment degree, which can be widely applied in the pre-treatment process of the pyrethroid insecticide residues of the environmental, biological and food samples, etc.

A process for isolating microorganisms from samples, particularly Shigella spp. from food samples, and a system, apparatus and composition therefor are provided. Magnetic particles are used to capture microorganisms and a system having separate magnetically-based apparatuses for collecting, concentrating and retrieving is used to isolate the magnetic particles having bound microorganisms. The apparatus for concentrating magnetic particles utilizes a small magnet assisted by vibration to concentrate collected particles at a localized region on the bottom of a container. The process, system and apparatus of the present invention are simple and inexpensive providing improved magnetic particle recovery adaptable to large scales.

The invention provides a solid-phase extraction column and a preparation method thereof. At the bottom of a column tube, the following operations are carried out in sequence: an outlet sieve plate is pressed in, a graphitized carbon black layer is filled in, a layer of insulating sieve plate is pressed in, a multi-amination packing layer is filled in, a hydrophobic group bonded silica gel resin layer is filled in after being pressed into the insulating sieve plate, and an inlet sieve plate is finally pressed in; and an outlet of the extraction column is arranged at the bottom of the column tube. The solid-phase extraction column provided by the invention is a pesticide residue detection special column and is made of a three-layer adsorbing material. Impurities, such as amino acid microelements, and heavy metal, can be removed by selectively adsorbing and selectively eluting and purifying a matrix of a complex sample, so that the defect of poor purification effect of the conventional solid-phase extraction product can be avoided, the cleaning degree of the sample is greatly improved, an analyzer is effectively protected, the accuracy of sample detection is improved, the detection sensitivity is improved, the time is saved, and the working efficiency of detectors can be improved. Furthermore, the solid-phase extraction column has the advantages of generality, and low selectivity of a matrix of the sample to be detected, and can be applicable to detection of most food samples.

The invention discloses a sample pretreatment method for detection of organochlorine pesticide residue in food and is characterized by comprising the following steps: water is added to a food sample, sample solution is swirled, and then inorganic salt and hydrophilic organic solvent are added to the sample solution, the sample solution is swirled and shaken uniformly, the sample solution undergoes phase splitting after centrifugation at room temperature, the upper-phase liquid is purified through dispersion solid-phase extraction method, the extraction temperature is 20-30 DEG C, and finally the upper-phase liquid is detected by gas chromatography; and the mass percent of the inorganic salt accounts for 5%-35% of the total mass of the system, the mass percent of the hydrophilic organic solvent accounts for 10%-50% of the total mass of the system, and water is of the residual amount, and the total mass of the system is the mass sum of water contained in the sample, the added water, the inorganic salt and the hydrophilic organic solvent. According to the sample pretreatment method, a dual-water-phase system consisting of the hydrophilic organic solvent, the organic salt and water is utilized, the partition coefficient is increased by means of changing the types and concentrations of the organic solvent and the inorganic salt, and the organochlorine pesticide residue in the sample can be directly extracted at room temperature.

Disclosed herein is a method of detecting a contaminant material in a food sample. The method includes irradiating a food sample with a beam of electromagnetic radiation, the beam having a plurality of frequencies in the range of about 100 GHz to about 2 THz; detecting radiation transmitted and / or reflected from the food sample; and, analyzing the detected radiation to determine the presence of contaminant material. The contaminant material may be melamine, cyanuric acid, ammeline, or ammelide.

The present invention relates to a browning detecting method of the liquid food. The liquid food is provided with fluorescence itself or is provided with fluorescence in browning. The method comprises the following procedures: obtaining a plurality of food samples with different browning degrees; collecting a fluorescence spectrum of the liquid food sample, and measuring the reference value representing the browning degree of the liquid food; establishing a corresponding relationship between the fluorescence spectrum and the browning degree according to the reference value; and collecting the fluorescence spectrum of the liquid food to be measured, and confirming the browning degree according to the corresponding relationship between the fluorescence spectrum and the browning degree. The liquid food browning detecting method of the invention executes browning detection to the liquid food which has fluorescence itself or generates fluorescent material in the browning procedure. The preliminary treatment of the sample is not required and the invention has advantages of high speed, no destruction, high sensitivity and broad application sphere. The on-line and real-time detection to the browning of the liquid food is provided with a supporting technique.

The invention discloses a determination method of residual amount of glufosinate, glyphosate and aminomethyl phosphoric acid in food. The determination method of residual amount of glufosinate, glyphosate and aminomethyl phosphoric acid in food comprises the following steps: in the sample pretreatment, firstly, extracting glufosinate, glyphosate and aminomethyl phosphoric acid in a food sample by a methanol water solution in sample pretreatment; then purifying an extracting solution by selecting a C18 dispersive solid-phase extraction agent; and finally, filtering, deriving, and determining three compounds qualitatively and quantitatively synchronously by combining with high performance liquid chromatography-tandem mass spectrum. According to the method provided by the invention, the operation is simple and convenient, and the reproducibility is good, and impurities in a sample extraction solution can be removed effectively; the pretreatment is the supplement and improvement of the existing QuEChERS method; the recycling rate can reach 70.5%-91.2%; the relative standard deviation is 4.5%-7.83%; the limit of quantification is 50micro-g / kg; the determination method can completely meet the technical requirement on safety detection of China, European Union, America and Japan, and can provide powerful technical support for food safety and export trade healthy development for people of China.

The invention discloses a pretreatment device for food detection. The pretreatment device for the food detection comprises a tank body, wherein a crushing grinding barrel is arranged inside the tank body; crushing blades are arranged inside the crushing grinding barrel; the crushing blades are fixedly connected with a moving sleeve; the moving sleeve is provided with a grinding plate below the crushing blades; the tank body is provided with a material guiding plate below the crushing grinding barrel; the tank body is provided with a material drawer below the material guiding plate. Through arrangement of the moving sleeve, a lifting plate, a transmission rod and a crankshaft, the moving sleeve moves up and down during rotation so as to drive the grinding plate and the crushing blades to rotate and move up and down to sufficiently crush and grind a food sample, so that the pretreatment efficiency is improved, the food sample meets detection requirements, and the detection efficiency isimproved; through arrangement of the crushing grinding barrel in transverse reciprocating movement, no dead corner exists during crushing and grinding, sieve hole blockage is avoided, and the discharging speed is increased.

The invention relates to a food insect attack degree distinguishing method based on a spectral imaging technology. The food insect attack degree distinguishing method mainly comprises the following steps: establishing a multispectral imaging system based on filter type according to hyperspectral imaging data, and establishing a distinguishing model of sample insect attack degree by extracting image features with sample feature wavelength. The food insect attack degree distinguishing method is characterized in that data volume collected by the spectral imaging system based on the feature wavelength is small; the model is simple and stable; food samples with different insect attack degrees can be distinguished; the food insect attack degree distinguishing method has important significance on food purchasing, storage and processing.

The invention discloses a colorimetric analysis method for detecting kanamycin based on aptamer-modified magnetic beads and gold nanoparticles to simulate enzyme activity, and belongs to the technical field of analytical chemistry. In the present invention, the gold nanoparticles synthesized by tyrosine reduction of chloroauric acid simulate the peroxidase-like activity inherent in the enzyme AuNPs, and the gold nanoparticles modified by kanamycin-specific aptamers modify their complementary single-stranded cDNA The capture of nanoparticles, and the displacement of gold nanoparticles by the combination of kanamycin and aptamer, the peroxidation-like peroxidation of gold nanoparticles AuNPs contained in the supernatant after magnetic separation is related to the concentration of kanamycin The enzyme activity catalyzes the color reaction between the substrate tetramethylbenzidine (TMB) and H2O2, realizes the visual detection of kanamycin, and uses the linear relationship between the absorption value at 450 nm and the concentration of kanamycin to realize the detection of kanamycin. Colorimetric quantitative analysis of kanamycin. This method has the advantages of high sensitivity and good specificity, and is suitable for the quantitative analysis of kanamycin residues in food samples such as honey.

The invention relates to an electrochemical lateral-flow immunity quantitative test paper sensor based on microclearance array electrode, and a method thereof used for detecting biological toxins such as ochratoxin A and fumonisin B1. The sensor includes two parts, namely, immune chromatographic analysis test paper strip and electrochemical detecting part. The fast detecting test paper sensor has strong specificity, can realize quantitative detection, can be used at the temperature between 4 and 40 DEG C, and the result can be observed after ten minutes, thus being suitable for units or individuals to quickly detect ochratoxin A and fumonisin B1 in animal derived food samples, and being expected to become an effective technical means for the field screening of ochratoxin A and fumonisin B1 in food and feed samples.

The invention relates to a method for electrochemically detecting acetamiprid by using a copper metallic organic frame compound (Cu-MOF) labeled DNA adapter sensor. The method comprises the steps of compounding a substrate material for a decorative electrode, labeling a signal probe DNA and establishing a sensing system. The marker Cu-MOF on the signal probe DNA (pDNA) is close to an electrode end, so that the electrode is easy to generate a sensitive electrochemical signal and the electrochemical signal is increased following the increasing of the concentration of the acetamiprid within a certain concentration range. The established electrochemical sensor can be used for sensitively detecting the acetamiprid, the pretreatment time and labor for the sample are saved and the cost of the detection instrument is lower. The method is sensitive and quick, the volume of the required sample is small and the method is suitable for the detection of the acetamiprid residue in the environment and various food samples.

The present invention is a portable device for detecting microorganisms in a food sample. The device includes a DNA extraction tube, a chip, and a portable control unit. The DNA extraction tube extracts DNA from the sample in an aqueous solution. The extraction tube includes successive chambers that are configured to mince, filter, and purify DNA in the form of an aqueous eluate. The chip includes reaction chambers disposed for a polymerase chain reaction to amplify a specific DNA fragment in the eluate for detection, and the portable control unit is configured to receive the chip and analyze the amplified DNA on the chip.

The invention discloses a food modeling and rapid detecting integration method and system adopting portable NIRS (near infrared spectroscopy). According to the method, the portable NIRS is secondarily developed under the windows system, a food detecting and calibrating model is established according to concentration reference values of component index parameters of a calibration set food sample as well as NIRS data, component parameters of a to-be-detected set sample food are detected by the calibrating model, and concentration detection values of to-be-detected components of unknown samples are obtained; an optimal detecting and calibrating model aiming at specific detected food objects can be obtained by adjusting model parameters. The integration system comprises a sample spectrum data collecting module, a sample spectrogram pre-processing module and a model establishment and evaluation analysis module. With the adoption of the method and the system, food components can be rapidly detected, according to the data characteristics of detected objects, the model can be established initiatively, the optimal parameters can be determined, the optimal model can be established, and accordingly, the detection precision of the model is improved.

This document provides methods and materials related to detecting allergens (e.g., food allergens) and / or specific antibodies in individualized consumers that are specific to an allergen (e.g., a food allergen). For example, methods and materials for assessing a food sample for the presence or absence of food allergens are provided. In addition, methods and materials for assessing if a particular human will react with those exact food allergens given his / her antibody profile are provided.

Isolated nucleic acids, kits and methods are disclosed for detecting, quantifying and / or identifying a fungal species in a sample or for diagnosing jejunal hemorrhage syndrome in a subject. The methods generally include amplifying a fungal nucleic acid sequence present in the sample using a primer selected from the group consisting of: SEQ. ID NO 5, SEQ. ID NO 6, SEQ. ID NO 7, SEQ. ID NO 8, SEQ. ID NO 9, SEQ. ID NO 10, SEQ. ID NO 11, SEQ. ID NO 12, SEQ. ID NO 13, SEQ. ID NO 14 or SEQ. ID NO 16; and observing or measuring the amplified nucleic acid sequence. The fungal species can thereby be detected, quantified, and / or identified. Fungal contamination also can be detected or measured in a biological or feed or food sample.

The invention discloses a surface enhanced Raman substrate material for detecting nitrite and a preparation method thereof. The preparation method comprises the following specific steps: (1) synthesizing a gold nano-rod by a crystal seed method; (2) preparing a p-mercaptoaniline modified gold nano-rod material; (3) synthesizing a gold nano-sphere by a hydrothermal method; (4) preparing a 1-amino-8-metcaptonaphthalene modified gold nano-sphere composite material; (5) mixing the p-mercaptoaniline modified gold nano-rod material and nitrite to generate diazonium salt; (6) mixing the diazonium salt and the 1-amino-8-metcaptonaphthalene modified gold nano-sphere composite material to generate azo-dye; (7) indirectly carrying out qualitative and quantitative detection on the nitrite by utilizing a surface enhanced Raman spectrum signal of the azo-dye. The surface enhanced Raman substrate material disclosed by the invention has good surface enhanced Raman activity on a substrate and can be used for rapidly detecting the nitrite in the environment and food samples.

The present invention provides a method for detecting fumonisin B1 based on fluorescence resonance energy transfer. The method comprises that: NaYF4:Yb,Ho upconversion fluorescence nanoparticles and gold nanoparticles are respectively and covalently bound to both ends of the stem-like part of the specific molecular beacon, wherein the fluorescence resonance energy transfer upconversion fluorescence can be quenched by the gold nanoparticles; and a fumonisin B1 aptamer and a complementary strand thereof are subjected to hybridization immobilization on the surface of magnetic nanoparticles, an analyte fumonisin B1 is added and is specifically bound with the aptamer so as to make the complementary strand be separated from the magnetic nanoparticles, and the separated complementary strand and the molecular beacon are subjected to hybridization so as to open the ring-like part of the molecular beacon, such that the fluorescence resonance energy transfer system is broken, the fluorescence signal is restored, and the fumonisin B1 content can be determined by detecting the fluorescence signal intensity, wherein the detection limitation of the method achieves 0.01 ng.mL<-1>. According to the present invention, the fumonisin B1 content in the food sample can be rapidly, accurately e and sensitively detected.

The invention relates to a method for promptly detecting biogenic amine in food and belongs to the food analysis and security technical field. The method for promptly detecting the biogenic amine in food comprises the following steps: (1) extracting the biogenic amine from food samples; (2) purifying biogenic amine extracting solution; (3) derivatizing the biogenic amine extracting solution; and (4) optimizing developing solvent and analyzing thin layer chromatography. The method for promptly detecting the biogenic amine in food can be used for promptly detecting biogenic amine content in products of fish, meat, cheese, wine, vinegar and the like. Compared with the other analysis methods, the method for promptly detecting biogenic amine in food has the advantages of being free of expensive analytical instruments, low in cost, easy to operate, fast, and capable of effectively lowering monitoring cost in food production and circulation.

A food testing device for testing for the presence of harmful contaminants in a food sample, includes a vessel adapted for holding a liquefied food sample, a liquefier operatively associated with the vessel for converting an unliquefied food sample into a liquefied food sample, at least one test assay dispensable from the device, wherein the test assay includes at least one assay reagent having an affinity for at least one harmful contaminant, and capable of both detecting the presence of the harmful contaminant in the liquefied food sample, and producing a visual cue upon recognition of the harmful contaminant; and a radiation detector disposed proximately to the vessel for indicating the presence of ionizing radiation in the food sample at amounts exceeding normal background levels to detect the presence of a radioactive agent as the harmful contaminant.

The invention provides a method for simultaneous detection of 3-chloropropanol ester and glycidyl ester in food. The method comprises the following steps: 1) pretreatment of a sample: dividing a food sample into two equal parts which are respectively used as food samples for a sample testing group A and a sample testing group B, and separately adding an internal standard solution into the food samples for ultrasonic extraction; 2) an ester interchange reaction: subjecting to-be-reacted solutions of the sample testing groups A and B to a hydrolysis reaction, then respectively adding a sodium chloride-acetic acid solution and a sodium sulfate-acetic acid solution into the reaction systems of the sample testing groups A and B to terminate the hydrolysis reaction, and then separately carrying out de-esterification with n-hexane; 3) a derivative reaction: adding a phenylboronic acid solution into residues obtained after de-esterification of the sample testing groups A and B for the derivative reaction;and 4) GC-MS detection and analysis. The method provided by the invention can simultaneously detect 3-chloropropanol ester and glycidyl ester in food, has high detection efficiency and is applicable to detection of a plurality of food samples.

The invention discloses a GC-Orbitrap-MS screening and analyzing method for pesticide residues in animal-derived food. The method comprises the following steps: (1) extraction: homogenizing an animal-derived food sample, mixing the homogenized animal-derived food sample with an extraction solvent and an extraction salt, carrying out oscillation extraction to obtain an extraction solution, and taking a supernatant I; (2) purification: mixing the supernatant I obtained in the step (1) with a purifying agent for purification, collecting a supernatant II, and filtering to obtain a to-be-detected liquid sample; (3) chromatography-mass spectrometry detection: separating pesticide residues in the to-be-detected sample solution by adopting gas chromatography, and then detecting by adopting Orbitrap-MS with an EI ion source so as to obtain the content of the pesticide residues in the animal-derived food. The method disclosed by the invention has the characteristics of high recovery rate, good precision, strong applicability, small organic reagent dosage and the like; various technical indexes can meet the requirements of daily detection and analysis of various animal-derived foods, and important technical support is provided for the field of food safety.