Application Notes: Food and Beverage

Gel Permeation Chromatography (GPC) is widely used for sample clean up in mycotoxin analysis. The most commonly described methods use GPC columns packed with SX-3 BioBeads suitable for cleaning Zearalenone, Aflatoxins, and Trichothesenes from edible oils and fatty matrices. Separation of Fumonisins from the oil fraction are inadequate with this column.

The recent establishment of a 1 μg/g safety threshold for melamine in infant foods has led to an immediate need for more sensitive methods. Here we established GC–MS conditions for highly reproducible analyses and evaluated the effectiveness of both solvent-based and matrix-matched standards. Using this method, melamine and cyanuric acid were reliably detected at and below 1 μg/g in infant formula.

The Biochrom 30 Amino Acid Analyser is a well established analytical instrument for clinical diagnosis as its IVD approval allows the diagnosis of inborn errors of metabolism such as Phenylketonuria.

Run a difficult food sample on your IC and you stand a big chance that you will wreck the column. Of course, you can waste a lot of time on tedious sample preparation steps to eliminate undesired matrix components. Or you can go for Metrohm's automated compact stopped-flow dialysis providing optimum separation while protecting your column from detrimental compounds.

This method is rapid and sensitive for the analysis of melamine and cyanuric acid simultaneously in infant formula. Using two Oasis solid-phase extraction protocols and the ACQUITY UPLC, the results are consistent with the published US FDA interim method, while demonstrating a reduced analysis time.

Melamine is an industrial chemical with a high nitrogen content that can cause kidney stones and lead to renal failure. In some instances, melamine has been added to baby formula and dairy products as a substitute for protein. This paper presents an efficient and definitive gas chromatography–mass spectrometry (GC–MS) method to identify melamine and related compounds based on the released US Food and Drug Administration (FDA) method.

Thermo

Melamine is an organic base and a trimer of cyanamide, with a 1,3,5-triazine skeleton. Melamine can react with formaldehyde to produce melamine resin, a very durable thermosetting plastic, and melamine foam, a polymeric cleaning product. Some end products made from melamine include countertops, dry erase boards, fabrics, glues, housewares, and flame retardants. Melamine is also one of the major components in Pigment Yellow 150, a colorant in inks and plastics.

LC–MS-MS instruments operating in Multiple Reaction Monitoring (MRM) are widely used for targeted quantitation on triple quadrupole and hybrid triple quadrupole linear ion trap (QTRAP® ) systems because of their well known selectivity and sensitivity. In MRM mode, the first quadrupole (Q1) filters a specific precursor ion; the collision cell (Q2) generates fragments (product ions) which are filtered in the third quadrupole (Q3). Although this double mass filtering greatly reduces noise there is always a chance that elevated background levels or matrix signals interfere with the targeted analyte.

The global economic downturn, particularly the collapse of the automotive and associated industries, has caused an overall reduction in the demand for acrylonitrile. Since acetonitrile is obtained as a co-product in the production of acrylonitrile, the pharmaceutical, food, environmental, and chemical industries are experiencing an unprecedented acetonitrile shortage. This shortage has resulted in a sharp price increase, in some cases as much as 6-8 times; and the price is projected to remain high even after the production returns to normal.

Since September 2008, 294,000 infants and young children suffered urinary problems due to the contamination of melamine in infant milk powder and were hospitalized. This hospitalization was required to treat the symptoms caused by the ingestion of melamine contaminated infant formula and related dairy products. Previously in 2007, pet food, animal feed, wheat gluten, and other protein-based foods were found to contain residues of melamine and its degradation product cyanuric acid (2).

The analysis of chemical residues in food requires techniques sensitive enough to detect and quantify contaminants at or below the maximum residue limit (MRL) of the compound in a given sample matrix. Because of increased food safety regulations and the growing numbers of samples to be analyzed, it is critical that the analytical techniques provide high sample throughput.

Melamine is an industrial chemical with a high nitrogen content that can cause kidney stones and lead to renal failure. In some instances, melamine has been added to baby formula and dairy products as a substitute for protein. This paper presents an efficient and definitive gas chromatography–mass spectrometry (GC–MS) method to identify melamine and related compounds based on the released US Food and Drug Administration (FDA) method.

Goal: Positively identify trace amounts of cannabinoids in a complex food matrix quickly, with minimal sample preparation and no chemical derivatization.

In March 2007, several North American manufacturers of pet food voluntarily issued nationwide recall notices for some of their products that were reportedly associated with renal failure in pets. The raw material wheat gluten, used to manufacture the pet food, was imported from China and was identified as the source of contamination.

The recent development of ultra-HPLC (UHPLC) has provided a great potential for high throughput analysis achieved using small (sub-2 μm) particle size columns at increased linear velocities. The advantage of UHPLC over conventional HPLC is increased throughput without sacrificing resolution. Despite their popularity, sub-2 μm particle columns impose practical difficulties, such as high backpressure (which often requires a UHPLC system) and susceptibility to column fouling. Thus difficulty can be overcome using 2.0 to 2.5 μm particles. This study describes an example (analysis of vanilla extract) of transferring a conventional LC method to a high-throughput method using newly developed Acclaim® RSLC 2-μm columns that are based on spherical, porous, high-purity silica particles (dp = 2 μm, pore size = 120 Å, surface area = 320 m2/g).

Recent developments in HRes Fast-LC systems have enabled the use of sub-3 μm stationary phases at higher flow rates and elevated pressures. HRes Fast-LC can provide significant improvements in both resolution and throughput.

Organic acids are present in many matrices and play crucial roles. Extensive research involving low molecular mass organic acids (LMMOA) has been performed in food chemistry since these acids contribute to the organoleptic properties of food and beverages, including flavor, color, aroma, taste, shelf-life, and health effects. Developing a profiling method to monitor LMMOA levels in raw materials and final products is very desirable. Many reported methods focus on limited numbers of LMMOAs and are incapable of providing a complete LMMOA profile.

Screening for pesticide content is a common analysis that is done in laboratories where many samples need to be analyzed over a short period of time. The desire for a high-speed analysis is due to the need for a fast result from a potentially large volume of samples. A fast analysis is typically achieved through the use of high carrier gas flow rates in combination with temperature programming. A fast detector is needed in order to fully characterize the narrow chromatographic peaks generated from these experiments. TOFMS is ideal for detecting these narrow peaks because of its fast acquisition rate over a full mass range at all times during the experiment. In addition, TOFMS provides for non-skewed mass spectra making peak deconvolution possible.

Mycotoxins, toxic secondary metabolites of several fungal species, represent food safety issues of high concern. Deoxynivalenol, the most abundant trichothecene mycotoxin, can be found worldwide as a contaminant of wheat, barley, maize and other cereals (1,2). The transmission of deoxynivalenol from barley into beer has been reported in several studies (3,4). Therefore, its levels should be controlled.

This article describes a straightforward ion chromatographic method that uses isocratic elution and pulsed amperometric detection (PAD) to sensitively determine water-soluble polyols and sugar alcohols as well as mono-, di- and oligosaccharides in essential and nonessential foodstuffs. While carbohydrate determination of most foodstuffs requires only minimal sample pretreatment such as dilution and filtration, samples with interfering matrices such as protein-containing dairy products have to be dialyzed prior to injection.

In March 2007, several North American manufacturers of pet food voluntarily issued nationwide recall notices for some of their products that were reportedly associated with renal failure in pets. The raw material wheat gluten, used to manufacture the pet food, was imported from China and was identified as the source of contamination.

With recent advances in technology and the use of ultra high pressure chromatography systems becoming more commonplace, it is of use to compare reproducibility of retention time and peak area of UHPLC vs HPLC.

Mycotoxins, toxic secondary metabolites of several fungal species, represent food safety issues of high concern. Deoxynivalenol, the most abundant trichothecene mycotoxin, can be found worldwide as a contaminant of wheat, barley, maize and other cereals (1,2). The transmission of deoxynivalenol from barley into beer has been reported in several studies (3,4). Therefore, its levels should be controlled.

Supercritical fluid chromatography (SFC) is a normal phase separation technique. In SFC, supercritical CO2 in combination with one or more polar organic solvents, most commonly alcohols, is used as the mobile phase. Owing to the lack of intermolecular interactions, supercritical fluid typically possesses lower viscosity and higher diffusivity than those solvents used in traditional high performance liquid chromatography (HPLC). This allows for higher flow rates, faster analyses, and the use of longer columns for higher chromatographic efficiencies. Initially deemed a niche chromatographic technique for chiral separation, the horizon of SFC applications has rapidly expanded to include achiral analyses of natural products, biodiesel, oligomer, pesticides/herbicides, and peptides. This is due, in part, to the improvements in detection choices and performances for SFC. Evaporative light scattering detectors (ELSDs) coupled with SFC have found wide use in many pharmaceutical and chemical laboratories (1).

In March 2007, several North American manufacturers of pet food voluntarily issued nationwide recall notices for some of their products that were reportedly associated with renal failure in pets. The raw material wheat gluten, used to manufacture the pet food, was imported from China and was identified as the source of contamination.

The natural colors of the food we eat add greatly to the enjoyment of life. Consequently, the art and science of recreating food's natural colors through the use of synthetic colorants is an important success factor in the food industry.