SIMULTANEOUS DETERMINATION OF FREE AMINO ACIDS, L-CARNOSINE, PURINE, PYRIMIDINE, AND NUCLEOSIDES IN MEAT BY LIQUID CHROMATOGRAPHY/SINGLE QUADRUPOLE MASS SPECTROMETRY

<div><p>A novel approach to single-run determination of 25 free amino acids, L-carnosine, 4 nitrogen bases (purine and pyrimidine), and 5 nucleosides in unpurified biological samples is reported. The analytes were extracted from the sample, derivatized with dansyl chloride, and analyzed using RP-HPLC-DAD-ESI-MS. The reported method features high sensitivity (LOQs in 5–10 ng mL⁻¹ range), wide linearity range with <i>r</i> > 0.94, and high precision (intra-day RSD within the 0.1–4.2% range). Analyte average recovery coefficient was in the 70.1–111.3% range. The method was used to determine levels of free amino acids, L-carnosine, nitrogen bases, and nucleosides in beef (strip loin). Evolution of concentrations of the studied compounds during meat storage processes (vacuum packing, cold storage) was also investigated.</p> </div

Application of Liquid Chromatography/Ion Trap Mass Spectrometry Technique to Determine Ergot Alkaloids in Grain Products

A liquid chromatography/ion trap mass spectrometry-based method to determine six ergot alkaloids and their isomers is presented. The samples were cleaned on neutral alumina-based solid-phase extraction cartridges. The following method parameters were obtained (depending on the analyte and spiking level): method recovery from 63.0 to 104.6 %, relative standard deviation below 18 %, linear range from 1 to 325 μg/kg, linear correlation coefficient not less than 0.98. The developed analytical procedure was applied to determine the levels of ergot alkaloids in 65 samples of selected rye-based food products (flour– 34 samples, bran – 12 samples, rye – 18 samples, flakes – 1 sample). Measurable levels of alkaloids were found in majority of the analysed samples, particularly in rye flour. Additionally, alkaloids were determined in ergot sclerotia isolated from rye grains. Total content was nearly 0.01 % (97.9 mg/kg). However, the alkaloid profi le was dominated by ergocristine at 45.6 % (44.7 mg/kg), an alkaloid not commonly found in the tested food products. Ergocorninine at 0.2 % (0.2 mg/kg) was the least abundant alkaloid

Cannabinoids—Characteristics and Potential for Use in Food Production

Scientific demonstrations of the beneficial effects of non-psychoactive cannabinoids on the human body have increased the interest in foods containing hemp components. This review systematizes the latest discoveries relating to the characteristics of cannabinoids from Cannabis sativa L. var. sativa, it also presents a characterization of the mentioned plant. In this review, we present data on the opportunities and limitations of cannabinoids in food production. This article systematizes the data on the legal aspects, mainly the limits of Δ9-THC in food, the most popular analytical techniques (LC-MS and GC-MS) applied to assay cannabinoids in finished products, and the available data on the stability of cannabinoids during heating, storage, and access to light and oxygen. This may constitute a major challenge to their common use in food processing, as well as the potential formation of undesirable degradation products. Hemp-containing foods have great potential to become commercially popular among functional foods, provided that our understanding of cannabinoid stability in different food matrices and cannabinoid interactions with particular food ingredients are expanded. There remains a need for more data on the effects of technological processes and storage on cannabinoid degradation

Degradation of Preservatives with the Formation of Off-Odor Volatile Compounds—The Case of Strawberry-Flavored Bottled Water

Foods preserved with sorbic acid or its salts can undergo spoilage with the formation of chemicals characterized by odors of plastic, hydrocarbons, or kerosene. 1,3-pentadiene, which is formed through the decarboxylation of sorbic acid or its salts, is one such compound. Numerous species of molds and yeasts have been reported as capable of degrading sorbic acid. This work is aimed to identify the off-odor compounds in samples of strawberry-flavored water preserved with potassium sorbate and sodium benzoate. In addition, the mold isolated from this drink was evaluated for the ability to form undesirable compounds, and the results revealed the presence of 1,4-pentadiene and benzaldehyde in the tested samples. The mold isolated from the samples was identified as Penicillium corylophilum. During its 5-day incubation at 25 &deg;C in a liquid medium, potassium sorbate added at a final concentration of 200 and 400 mg/L was completely assimilated by the growing mycelium and converted into 1,4-pentadiene. The concentration of the latter was determined as 46.5 and 92.6 mg/L, respectively. The decrease in the concentration of sodium benzoate exceeded 53% in the broth spiked at 200 mg/L and 23% at 400 mg/L, resulting in the formation of benzaldehyde

Time Evolution of Microbial Composition and Metabolic Profile for Biogenic Amines and Free Amino Acids in a Model Cucumber Fermentation System Brined with 0.5% to 5.0% Sodium Chloride

Salt concentrations in brine and temperature are the major environmental factors that affect activity of microorganisms and, thus may affect formation of biogenic amines (BAs) during the fermentation process. A model system to ferment cucumbers with low salt (0.5%, 1.5% or 5.0% NaCl) at two temperatures (11 or 23 °C) was used to study the ability of indigenous microbiota to produce biogenic amines and metabolize amino acid precursors. Colony counts for presumptive Enterococcus and Enterobacteriaceae increased by 4 and up to 2 log of CFU∙mL−1, respectively, and remained viable for more than 10 days. 16S rRNA sequencing showed that Lactobacillus and Enterobacter were dominant in fermented cucumbers with 0.5% and 1.5% salt concentrations after storage. The initial content of BAs in raw material of 25.44 ± 4.03 mg∙kg−1 fluctuated throughout experiment, but after 6 months there were no significant differences between tested variants. The most abundant BA was putrescine, that reached a maximum concentration of 158.02 ± 25.11 mg∙kg−1. The Biogenic Amines Index (BAI) calculated for all samples was significantly below that needed to induce undesirable effects upon consumption. The highest value was calculated for the 23 °C/5.0% NaCl brine variant after 192 h of fermentation (223.93 ± 54.40). Results presented in this work indicate that possibilities to control spontaneous fermentation by changing salt concentration and temperature to inhibit the formation of BAs are very limited

Profile of congeners found in BDE-positive bee pollen samples.

<p>Profile of congeners found in BDE-positive bee pollen samples.</p

Breakdown of pesticides found in the analyzed bee pollen samples (sorted in descending order by the number of positive samples).

<p>Breakdown of pesticides found in the analyzed bee pollen samples (sorted in descending order by the number of positive samples).</p

Factors Influencing the Accumulation of Free Asparagine in Wheat Grain and the Acrylamide Formation in Bread

Asparagine is one of the precursors of acrylamide that can form during bread production. The aim of this work was to determine the effect of genotype, environment, sulfur fertilization, and the interaction of those factors on the asparagine content, technological value of wheat, and acrylamide level in bread. The research material consisted of five wheat cultivars grown in two locations in Poland with nitrogen fertilization of 110 kg ha−1 and sulfur fertilization of 30 kg ha−1. The standard ISO method for analyzing the milling and baking properties of wheat was used. The UHPLC-MS/MS method for analyzing the amino acids and the GC/MS method for acrylamide in bread were implemented. The analysis of variance results indicated that the location influenced the total variance in the measured asparagine content and quality of wheat the most, followed by the cultivar and then by the interaction between the environment and cultivar. Sulfur fertilization had no significant effect on the asparagine content, but slightly lowered the gluten quality and loaf volume of bread. However, sulfur fertilization in connection with the cultivar characterized by low starch damage had a positive effect on lowering the acrylamide in bread. Asparagine content in wheat and acrylamide in bread varies mostly depending on cultivar and environment

Bee pollen sampling locations.

<p>Bee pollen sampling locations.</p