Evaluation and detoxification of aflatoxins in ground and tree nuts using food grade organic acids

The contamination of foodstuffs especially nuts with aflatoxins (AFs) affected by some of the fungal genera species is a major threat to the economy, safe food supply and serious health concerns to any country in recent days. Recently different techniques including heat, ozone and microbes are used for the decontamination of aflatoxin but all these are limited to achieve the desirable results. The present study objectives to decontaminate AFs in nuts by using three food-grade organic acids. The aqueous solutions of three food-grade organic acids namely citric, lactic and propionic acid are used at five different concentrations (1, 3, 5, 7 and 9%) to detoxify aflatoxin B1 (AFB1) and total aflatoxins (TAFs) that includes ;AFB1, AFB2, AFG1 and AFG2 in selected nuts including almond, peanut, pistachio and walnut at two different moisture levels (10 ± 3 and 16 ± 3%). The high-performance liquid chromatography (HPLC) coupled with fluorescence detection method was applied for the qualitative and quantitative determination of AFs. The results showed that the decontamination of AFB1 and TAFs significantly increased in infected nuts by increasing the concentration of acids. The experimental results after 15 min treatment of walnut (10 ± 3 and 16 ± 3% moisture level), pistachio (10 ± 3% moisture content) and peanuts (10 ± 3% moisture content) with citric, lactic and propionic acids at 9% concentration significantly reduced AFs about 99, 99.90 and 96.07% respectively. Furthermore, treatment with citric and lactic acids resulted in the conversion of AFB1 into less toxic products identified as AFD1 via hydrolysis of the lactone ring. Furthermore, citric acid was found as the most efficient acid in degrading the TAFs among all three organic acids. The present study showed better AFs detoxification results than conventional methods. Hence, it is concluded that citric, lactic, and propionic acids can be applied as a useful and safe decontamination method for AFB1 and TAFs in aflatoxin-affected nuts

Technological properties of maize tortillas produced by microwave nixtamalization with variable alkalinity

This research was conducted to determine the quality, physicochemical, textural, compositional, nutritional, viscoamylographic and sensory properties of maize tortillas produced with a Modified tortilla-making process (MTMP) of variable alkalinity (0.125, 0.25 and 0.5% Ca(OH)2 w/w) and compared to the commercial brand MASECA ®. In general, tortillas from MTMP showed higher pH, total color difference (ΔE), tensile strength/cutting force, protein, lipids, crude fibre, lysine, tryptophan, in vitro protein digestibility and lower Hunter L value, loss of weight during cooking and moisture content than MASECA® tortillas. No significant differences were found in the sensory analysis of 22 descriptors of tortillas made from MASECA® and MTMP with Ca(OH)2 concentrations of 0.125 and 0.25% (w/w). However, panelist identified principal effects on changes in four attributes (aroma, appearance, flavor, and after taste flavor) and seven descriptors in tortillas from MTMP prepared with the maximum lime concentration (0.5% w/w). Microwave nixtamalization produce tortillas with acceptable physicochemical, textural, quality, compositional/nutritional and pasting properties.Key words: Maize, modified nixtamalization, tortillas, technological properties

Electrodeposition of Ni-P/SiC Composite Films with High Hardness

This chapter describes the effect of SiC particle concentrations on the metallic continuous phase of the coating and the effect of heat treatment on the crystalline structure, hardness, and wear resistance of electrodeposited Ni-P-SiC coatings. The deposits were obtained via electrodeposition onto an AISI 1018 steel electrode and then heat treated at various temperatures ranging from 300 °C to 600 °C for 60 min in air. The tribological characteristics studied included hardness, friction coefficient, and wear resistance. The results indicated that the dispersion of SiC particles in the metallic matrix improves coating tribological properties such as hardness and wear resistance while diminishing the friction coefficient. The Ni-P-SiC alloy was originally amorphous and was transformed into a mixture of amorphous and crystalline phases when was thermally treated in the range from 400 °C to 500 °C. This phase transformation was associated with the precipitation of a mixture of Ni3P intermetallic compound and pure Ni crystals. In addition, the results showed that the wear resistance of the Ni-P-SiC coating increased with hardness. The maximum hardness (1453.4 HV) was obtained when the Ni-P-SiC coatings were thermally treated at 500 °C

Changes in cocoa properties induced by the alkalization process: A review

[EN] Alkalization, also known as "Dutching," is an optional, but very useful, step taken in the production chain of cocoa to darken its color, modify its taste, and increase natural cocoa solubility. Over the years, various attempts have been made to design new and more effective alkalization methods. Moreover, different authors have attempted to elucidate the impact of alkalization on the physicochemical, nutritional, functional, microbiological, and sensory characteristics of alkalized cocoa. The aim of this review is to provide a clear guide about not only the conditions that can be applied to alkalize cocoa, but also the reported effects of alkalization on the nutritional, functional, microbiological, and sensory characteristics of cocoa. The first part of this review describes different cocoa alkalization systems and how they can be tuned to induce specific changes in cocoa properties. The second part is a holistic analysis of the effects of the alkalization process on different cocoa features, performed by emphasizing the biochemistry behind all these transformations.European Regional Development Fund, Grant/Award Number: Project RTC-2016-5241-2; Ministerio deEconomia y Competitividad, Grant/Award Number: Project RTC-2016-5241-2Valverde-Garcia, D.; Pérez-Esteve, É.; Barat Baviera, JM. (2020). Changes in cocoa properties induced by the alkalization process: A review. Comprehensive Reviews in Food Science and Food Safety. 19(4):2200-2221. https://doi.org/10.1111/1541-4337.12581S22002221194Ilesanmi Adeyeye, E. (2016). Proximate, Mineral And Antinutrient Compositions Of Natural Cocoa Cake, Cocoa Liquor And Alkalized Cocoa Powders. Journal of Advanced Pharmaceutical Science And Technology, 1(3), 12-28. doi:10.14302/issn.2328-0182.japst-15-855Ajandouz, E. H., Tchiakpe, L. S., Ore, F. D., Benajiba, A., & Puigserver, A. (2001). 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Trends in Food Science & Technology, 86, 199-208. doi:10.1016/j.tifs.2019.02.035Huang, Y., & Barringer, S. A. (2010). Alkylpyrazines and Other Volatiles in Cocoa Liquors at pH 5 to 8, by Selected Ion Flow Tube-Mass Spectrometry (SIFT-MS). Journal of Food Science, 75(1), C121-C127. doi:10.1111/j.1750-3841.2009.01455.xHurst, W. J., Krake, S. H., Bergmeier, S. C., Payne, M. J., Miller, K. B., & Stuart, D. A. (2011). Impact of fermentation, drying, roasting and Dutch processing on flavan-3-ol stereochemistry in cacao beans and cocoa ingredients. Chemistry Central Journal, 5(1). doi:10.1186/1752-153x-5-53International Cocoa Organization(2017).Annual report 2014/2015 Retrieved fromhttps://www.icco.org/about-us/international-cocoa-agreements/cat_view/1-annual-report.html.Mazor Jolić, S., Radojčić Redovniković, I., Marković, K., Ivanec Šipušić, Đ., & Delonga, K. (2011). Changes of phenolic compounds and antioxidant capacity in cocoa beans processing. International Journal of Food Science & Technology, 46(9), 1793-1800. doi:10.1111/j.1365-2621.2011.02670.xKofink, M., Papagiannopoulos, M., & Galensa, R. (2007). (-)-Catechin in Cocoa and Chocolate: Occurence and Analysis of an Atypical Flavan-3-ol Enantiomer. Molecules, 12(7), 1274-1288. doi:10.3390/12071274Kongor, J. E., Hinneh, M., de Walle, D. V., Afoakwa, E. O., Boeckx, P., & Dewettinck, K. (2016). Factors influencing quality variation in cocoa (Theobroma cacao) bean flavour profile — A review. Food Research International, 82, 44-52. doi:10.1016/j.foodres.2016.01.012Kopp G. M. Hennen J. C. Seyller M. &Brandstetter B.(2010).Process for producing high flavour cocoa. EP2241190A1.Kruszewski, B., & Obiedziński, M. W. (2020). Impact of Raw Materials and Production Processes on Furan and Acrylamide Contents in Dark Chocolate. Journal of Agricultural and Food Chemistry, 68(8), 2562-2569. doi:10.1021/acs.jafc.0c00412Lan, X., Liu, P., Xia, S., Jia, C., Mukunzi, D., Zhang, X., … Xiao, Z. (2010). Temperature effect on the non-volatile compounds of Maillard reaction products derived from xylose–soybean peptide system: Further insights into thermal degradation and cross-linking. Food Chemistry, 120(4), 967-972. doi:10.1016/j.foodchem.2009.11.033Li, Y., Feng, Y., Zhu, S., Luo, C., Ma, J., & Zhong, F. (2012). The effect of alkalization on the bioactive and flavor related components in commercial cocoa powder. Journal of Food Composition and Analysis, 25(1), 17-23. doi:10.1016/j.jfca.2011.04.010Li, Y., Zhu, S., Feng, Y., Xu, F., Ma, J., & Zhong, F. (2013). Influence of alkalization treatment on the color quality and the total phenolic and anthocyanin contents in cocoa powder. Food Science and Biotechnology, 23(1), 59-63. doi:10.1007/s10068-014-0008-5Lima, L. J. R., Kamphuis, H. J., Nout, M. J. R., & Zwietering, M. H. (2011). Microbiota of cocoa powder with particular reference to aerobic thermoresistant spore-formers. 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Colorimetric detection of the potent carcinogen aflatoxin B1 based on the aggregation of L-lysine-functionalized gold nanoparticles in the presence of copper ions

L-lysine functionalized gold nanoparticles (AuNPs-Lys) have been widely used for the detection of worldwide interest analytes. In this work, a colorimetric assay for the detection of the carcinogen aflatoxin B1 (AFB1) based on the aggregation of AuNPs-Lys in the presence of copper ions was developed. For this purpose, AuNPs were synthesized in citrate aqueous solution, functionalized, and further characterized by UV–Vis, fluorescence, Fourier transform infrared spectroscopy (FTIR), nanoparticle tracking analysis (NTA), dynamic light scattering (DLS), and transmission electron microscopy (TEM). In general, AuNPS-Lys (~2.73 × 1011 particles) offered a clear colorimetric response in the presence of AFB1 and Cu2+ ions showing linearity in the range of 6.25 to 200 ng AFB1/mL, with a detection limit of 4.18 ng AFB1/mL via photometric inspection. Moreover, the performance of the proposed methodology was tested using the 991.31 AOAC official procedure based on monoclonal antibodies in maize samples artificially contaminated with AFB1. There was a good agreement between the measured AFB1 concentrations in both assays, the average recoveries for the colorimetric and immunoaffinity assays were between 91.2–98.4% and 96.0–99.2%, respectively. These results indicated that the colorimetric assay could be used as a rapid, eco-friendly, and cost-effective platform for the quantification of AFB1 in maize-based products

Enfrentando los riesgos socionaturales

El objetivo del libro es comprender la magnitud de los Riesgos Socionaturales en México y Latinoamérica, para comprender el peligro que existe por algún tipo de desastre, ya sea inundaciones, sismos, remoción en masa, entre otros, además conocer qué medidas preventivas, correctivas y de contingencias existen para estar atentos ante alguna señal que la naturaleza esté enviando y así evitar alguna catástrofe. El libro se enfoca en los aspectos básicos de análisis de los peligros, escenarios de riesgo, vulnerabilidad y resiliencia, importantes para la gestión prospectiva o preventiva

Métodos y técnicas de monitoreo y predicción temprana en los escenarios de riesgos socionaturales

Esta obra concentra los métodos y las técnicas fundamentales para el seguimiento y monitoreo de las dinámicas de los escenarios de riesgos socionaturales (geológicos e hidrometeorológicos) y tiene como objetivo general orientar, apoyar y acompañar a los directivos y operativos de protección civil en aterrizar las acciones y políticas públicas enfocadas a la gestión del riesgo local de desastre