For most NMR applications, higher external magnetic field strengths are preferred for better dispersion and sensitivity, but are usually outside the budgets of educational labs. The good news is the Fourier 80 can do the job with a little help from auxiliary agents and Bruker’s step-by-step protocols designed for students. Download PDF
The process of using NMR for molecular structure identification and verification can be applied to many real-world examples to enhance a student‘s learning experience. In these protocols, students are given the chance to apply NMR technology to evaluate samples many of them are probably very familiar with; coffee and milk. Download PDF
In the refining process for edible oils conditions must be carefully controlled to avoid the formation of toxic process contaminants, such as 2-MCPD, 3-MCPD, glycidol and their fatty acid esters. An automated GC/MS-method now enables highly efficient determination of these compounds based on standard methods such as ISO 18363-1, AOCS Cd 29c-13, and DGF C-VI…
Mineral oil hydrocarbon (MOH) contaminants can be found in foods such as cereals, baked goods, fats and oils, coffee and many more. MOH can be introduced through process aids, additives, and machine- and lubricating oils used during food processing. Packaging such as jute bags used to store and transport foods, recycled cardboard, and printing inks…
The objective of this note focuses on the fully automated solution of the determination of 3-monochloropropanediol (3-MCPD) and glycidol in edible oils based on the AOCS Cd 29a-13 methods. This method is also applicable for the determination of 2-monocloropropanediol (2-MCPD). The glycidyl esters first react with acidified sodium bromide to form its 3-monobromopropanediol (3-MBPD) ester…
Rancidity of vegetable oils is a major problem in food related industries. It occurs during storage and is caused by oxidation of unsaturated fatty acids, resulting in foul odors and tastes in the product. Oxidative stability is affected by a number of factors including oxygen, temperature, presence of metals and light. The resistance of edible…
The time domain nuclear magnetic resonance (TD-NMR) measurement of Solid Fat Content (SFC) in fats and fat compositions using the Direct and Indirect method are well established official standard methods (ISO, AOCS, IUPAC). While the measurement takes just 6 seconds ,the sample preparation (including melting the fat or fat mixture, filling the sample tube, tempering…
Bruker’s versatile and easy-to-use bench-top TD-NMR analyzer is a turn-key solution for rapid Quality/Process control in snack food manufacturing. It acquires time-domain data in a mater of seconds to quantitatively determine physical and chemical properties of materials. The signal is obtained from the hydrogen atomic nuclei present the samples. The relaxation behaviors of the NMR…
Solid Fat Content (SFC) determination is of prime importance for food processing and development. Raw materials like fat compositions or blends need to be characterized and controlled according to their melting profiles. The SFC determination by time domain (TD) NMR analysis is the internationally recognized standard method. In a close partnership with the oil &…
Water-in-oil (W/O) and oil-in-water (O/W) emulsions are found in everyday meals, mainly as margarine, low fat spread, and butter (W/O) or, as mayonnaise, salad dressing, and soft cheese (O/W). The droplet size distribution in these emulsions influences their taste, smell, and appearance, as well as their shelf life and spread behavior. Bruker’s minispec allows a…
Since seeds are pressed to extract the oil, the price of seeds depends on their oil content and thereby farmers are paid accordingly. Therefore, oil mills and analytical laboratories evaluate large amounts of samples every day, especially during the harvest season. Moisture content is controlled to ensure good storage. Additionally moisture has to be carefully…
Two species of spearmint are cultivated in the United States. In 2008, 1.09 million kilograms of spearmint oil were produced in the U.S.(1) Forty-five percent of U.S. spearmint oil is used to flavor chewing gum. One 55-gallon drum of mint oil can flavor 5,200,000 sticks of gum or 400,000 tubes of toothpaste.(2) Sulfur compounds impart…
In 1986 the United States Environmental Protection Agency (USEPA) introduced Method 502.2 (1) to monitor the levels of 60 aromatic and halogenated volatile organic compounds (VOCs) in drinking water. Some of the volatile contaminants on this list are halogen-containing VOCs, and others contain aromatic properties. The unique characteristics of these components make them excellent candidates…
Although analysis of VOCs by purge and trap is considered a mature technique, advances in methodology and refinement of instrumentation are still being developed. This application note presents suggested operating conditions for the 4760 purge and trap and the 4100 autosampler. Download PDF
USEPA Method 524.2 has been used by laboratories for many years for the analysis of volatile organic compounds in drinking water by purge and trap concentration with detection using Gas Chromatography/Mass Spectrometry (GC/MS). This method requires an 11 minute purge at 40 mL/minute and a 4 minute desorb. The 4 minute desorb transfers a significant…
The analysis of organic compounds in aqueous environmen tal, biomedical, food and fragrance matrices is normally performed after extraction and enrichment of the solutes from the matrix (drinking water, waste water, body fluids, beverages,…). Most used sample preparation methods are based on liquid-gas extraction or equilibrium (purge and trap, headspace), liquid-liquid extraction or solid phase…
2,4,6-Trichloroanisole (TCA) is well known as being the main cause for corkiness in wine. Its extremely low odor threshold usually mandidates enrichment and concentration steps before it is available for precise quantitation. This paper describes the applicability of a recently developed, novel and simple approach for sorptive extraction of organic compounds from aqueous samples for…
The analysis of flavor compounds in beverages such as coffee, tea, soft drinks and alcoholic beverages usually requires cumbersome sample preparation steps such as liquid/liquid extraction, solid phase extraction or distillation techniques, often with the drawback of organic solvent use. Headspace and purge & trap methods do not use organic solvents, but their analyte range…