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Agnieszka Koszucka Adriana Nowak 《Critical reviews in food science and nutrition》2019,59(22):3579-3596
AbstractHeterocyclic aromatic amines, acrylamide, 5-hydroxymethylfurfural, furan, polycyclic aromatic hydrocarbons, nitrosamines, acrolein, chloropropanols and chloroesters are generated toxicants formed in some foodstuffs, mainly starchy and protein-rich food during thermal treatment such as frying, roasting and baking. The formation of these chemical compounds is associated with development of aromas, colors and flavors. One of the challenges facing the food industry today is to minimize these toxicants without adversely affecting the positive attributes of thermal processing. To achieve this objective, it is essential to have a detailed understanding of the mechanism of formation of these toxicants in processed foods. All reviewed toxicants in that paper are classified as probable, possible or potential human carcinogens and have been proven to be carcinogenic in animal studies. The purpose of that review is to summarize some of the most frequent occurring heat-generated food toxicants during conventional heating, their metabolism and carcinogenicity. Moreover, conventional and microwave heating were also compared as two different heat treatment methods, especially how they change food chemical composition and which thermal food toxicants are formed during specific method. 相似文献
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María G. Venegas‐Ortega Adriana C. Flores‐Gallegos Jos L. Martínez‐Hernndez Cristbal N. Aguilar Guadalupe V. Nevrez‐Moorilln 《Comprehensive Reviews in Food Science and Food Safety》2019,18(4):1039-1051
Traditional fermented foods where lactic acid bacteria (LAB) are present have been associated with beneficial effects on human health, and some of those benefits are related to protein‐derived products. Peptides produced by LAB have attracted the interest of food industries because of their diverse applications. These peptides include ribosomally produced (bacteriocins) and protein hydrolysates by‐products (bioactive peptides), which can participate as natural preservatives and nutraceuticals, respectively. It is essential to understand the biochemical pathways and the effect of growth conditions for the production of bioactive peptides and bacteriocins by LAB, in order to suggest strategies for optimization. LAB is an important food‐grade expression system that can be used in the simultaneous production of peptide‐based products for the food, animal, cosmetic, and pharmaceutical industries. This review describes the multifunctional proteinaceous compounds generated by LAB metabolism and discusses a strategy to use a single‐step production process, using an alternative protein‐based media. This strategy will provide economic advantages in fermentation processes and will also provide an environmental alternative to industrial waste valorization. New technologies that can be used to improve production and bioactivity of LAB‐derived peptides are also analyzed. 相似文献
97.
Carlos Cardoso Romina Gomes Ana Rato Sandra Joaquim Jorge Machado Jos Fernando Gonalves Paulo Vaz‐Pires Leonardo Magnoni Domitília Matias Inês Coelho Inês Delgado Isabel Castanheira Joana Matos Rodrigo Ozrio Narcisa Bandarra Cludia Afonso 《Food Science & Nutrition》2019,7(8):2495-2504
The Pacific oyster (Crassostrea gigas) culture has been expanding, thereby leading to a greater importance of hatcheries. Broodstock conditioning is very important in the hatchery process, in which diet composition may have a strong influence on the offspring production and quality. Therefore, the current study evaluated elemental composition and bioaccessibility of oysters fed different ratios of dietary seaweed (SW) and microalgae. The dietary conditioning consisted of direct replacement of microalgae by SW at four substitution levels (0%, 25%, 50%, and 100% diet). It was observed that oysters fed 100% SW had the highest levels of Be, Cu, Zn, Sr, and Cd. The most important trend was a concentration decline of most elements with progressively lower levels of SW substitution for microalgae in the feeds. No Cd or Pb hazard (contents below 1.0 mg/kg for Cd and 1.5 mg/kg for Pb) was found in oyster meat. Regarding elemental bioaccessibility, values were similar, near 100% in the cases of Cu, Br, and I. Only for Mn and Pb, bioaccessibility percentages deviated more from 100%. Indeed, the value for Pb was 50% ± 7% (initial group), and for Mn, all values were equal or lower than 29% ± 2% (final group of oysters fed microalgae). It was observed that Mn, Cd, and Pb bioaccessibility increased with a growing share of microalgal biomass in the feed. Therefore, this study showed that SW incorporation into the feed influences elemental composition and bioaccessibility of the oysters. 相似文献
98.
There were studied 33 patients admitted with clinical diagnosis of superficial herpetic keratitis, typical form of dendritic ulcer. In all these cases there were performed smears from the level of cornea and conjunctiva, that were stained with rapid blue polycrome tanin Dragan staining method. Smears were performed before and during the evolution of the disease, in patients specifically treated with antiviral drugs and also in cases treated unspecifically. There are described some cytological particularities which have a relative specificity for the diagnosis: a high number of lymphocytes with cytoplasmic blebs, giant multinucleated cells, and epithelial cells with degenerative lesions (nucleocytoplasmic inclusions, vacuoles, chromophobe halo around nucleus). Such lesions were not observed in patients with non herpetic keratitis. Modifications noticed in epithelial corneal cells could suggest the diagnosis, which can be associated with clinical examination, in order to administer a specific therapy. Dynamic cytological evolution shows early regression of specific cellular modifications in patients treated by Acyclovir. 相似文献
99.
100.
M Delgado EJ Munoz-Elias Y Kan I Gozes M Fridkin DE Brenneman RP Gomariz D Ganea 《Canadian Metallurgical Quarterly》1998,273(47):31427-31436