Rapid assessment of enniatins in barley grains using near infrared spectroscopy and chemometric tools.

Barley is an important crop worldwide, and it can be affected by various fungi, among them Fusarium is one of the most relevant due to the economic losses caused by mycotoxin contamination. Enniantins (ENNs) are one of the emergent group of mycotoxins that have been found in grains around the world. Nowadays, the main analytical tools available to evaluate these contaminants are based on chromatographic techniques that are efficient but time-consuming and expensive. In this context, the present study aimed to assess the performance of near infrared (NIR) spectroscopy to detect and/or classify the enniatin (ENN) content on barley grains. Sixty samples of barley grains from three different regions of Brazil were investigated and the ENN content determined by UPLC-MS/MS. The levels found were then used to develop multivariate models based on infrared spectral data. The results indicated high incidence off ENN presence in the samples (>70 %) and the PLS-DA model determined by NIR data showed adequate values of sensitivity and sensibility (100 % and 94.2 %, respectively) distinguishing between contaminated and non-contaminated barley samples, demonstrating NIR as a promising tool to monitoring this emergent mycotoxin.

Static in vitro digestion methods for assessing essential minerals in processed meat products.

The consumption of processed meat products has increased due to its convenient preparation and characteristics related to taste and consumer acceptance. In this study, we evaluated the content and bioaccessibility of iron (Fe), zinc (Zn), calcium (Ca) and magnesium (Mg) in processed pork and beef products by dialysis assay. In addition, different assays of static in vitro digestion (traditional solubility and INFOGEST) were applied to verify the results on the bioaccessibility of these essential elements. The average content of essential elements (expressed in mg/100 g) were 0.78 ± 0.24 and 1.51 ± 0.51 for Fe; 1.79 ± 0.55 and 3.57 ± 1.42 for Zn; 13.24 ± 9.99 and 20.29 ± 10.45 for Ca and 19.43 ± 2.78 and 26.15 ± 7.33 for Mg, in pork and beef products, respectively. However, we observed high variation between brands and batches. The dialysis assay presented variations in bioaccessibility for all essential elements evaluated in the samples. The results for dialyzable Fe were lower than expected (in vivo assays), probably due to the mechanism simulated in dialysis. This assay was considered inadequate for the simulation of in vitro digestion for meat samples that contain heme-Fe. When comparing the different static in vitro digestion assays employed, the dialysis test showed the lowest bioaccessibility percentages for all essential elements evaluated, when compared with the other in vitro digestion methods. The highest bioaccessible fractions were obtained by applying the INFOGEST protocol. We found that according to the in vitro digestion simulation assay used, the results for bioaccessible percentage displayed high variation. These observations highlight the importance of the assay type used for this purpose. These results did not indicate which is the better assay, but demonstrated the differences of each and their relevance for estimating bioaccessibility of essential elements in meat products.

Identification of bioactive peptides released from in vitro gastrointestinal digestion of yam proteins (Dioscorea cayennensis).

Bioactive peptides have been broadly studied for their contribution to human health. This study aimed to identify bioactive peptides generated by in vitro gastrointestinal digestion of yam proteins. Yam protein concentrate (YPC) was submitted to simulated digestion. Gastric phase hydrolysate (GPH) and total gastrointestinal phase hydrolysate (GIPH) had their peptides identified by nanoLC-ESI-MS/MS. Peptide sequences were subjected to a database-driven (BIOPEP) bioactivity search. In vitro tests included: Antioxidant activity, DNA damage protection, ACE-inhibitory activity and antibacterial activity against the bacteria Escherichia coli, Salmonella sp. and Lysteria monocytogenes. Simulated digestion generated small peptides (mostly MW < 3500 Da), several of them with potential bioactive sequences predicted in silico. In both GPH and GIPH biological activities were detected, although GIPH displayed stronger DNA damage protection and antibacterial activity against Escherichia coli. The digestion of yam proteins releases promising biologically active peptides which can contribute to the prevention of bacterial infection and chronic degenerative diseases, with beneficial effects to human health.

Fortification of whole wheat flour with different iron compounds: effect on quality parameters and stability.

The aim of this study was to evaluate the effects of fortification of whole wheat flour with different iron compounds, such as ferrous sulfate (FS), ferrous fumarate (FF), reduced iron (RI), ferric sodium ethylenediaminetetraacetate (NaFeEDTA), microencapsulated ferrous sulfate (FSm) and microencapsulated ferrous fumarate (FFm), on quality parameters: color, titratable acidity, peroxide value (PV) and hexanal values, during 120 days of storage. An iron content of 1.38 mg/100 g was quantified in non-fortified whole wheat flour and after fortification, the iron levels ranged from 4.80 to 6.29 mg/100 g. The fortification of whole wheat flour with different iron compounds showed changes on the quality parameters evaluated during storage with exception of the color. The whole flour acidity was affected mainly by NaFeEDTA. Compounds FS and FFm presented the highest PV in whole flour after 30 days of storage. Whole flours fortified with FS and FSm presented higher hexanal levels after 30 and 90 days of storage, respectively. Whole flours fortified with RI and NaFeEDTA presented more stability on quality parameters evaluated during storage period. Therefore, the different iron compounds, when used on whole wheat flour fortification, affect differently the quality of the product during storage.

Determinaçao de folatos em espinafre - avaliaçao da influência do tipo de cultivo, época de colheita e cozimento / Folate determination in spinach: influence of cultivation, harvest and cooking methods

O objetivo desse trabalho foi e avaliar o teor das diferentes formas da vitamina, em espinafres produzidos por diferentes tipo de cultivo (orgâ e tradicional), distintas épocas de colheita e após cozimento em água. Para tanto utilizou-se a técnica de cromatografia líquida de alta eficiência. Espinafres cultivados de forma tradicional e orgânica não apresentaram diferença significativa nos teores de folatos, assim como tambén não se observou diferença significativa entre valores obtidos em diferentes períodos do ano. Os níveis de folatos medidos como 5-metilTHF e 5-formilTHF, variaram de 226 a 527 µg/100g e 4.6 to 10µ/100g, respectivamente. O cozimento em água resultou em perdas de aproximadamente 74 porcento para o 5-metilTHF e 56 porcento para o 5-formilTHF. Com base na determinação da concentração de folatos na água de cozimento, pode-se afirmar que as perdas se deram, principalemente, devido ao processo de lixiviação.