349 research outputs found
Antimicrobial agents and packaging systems in antimicrobial active food packaging: An overview of approaches and interactions
tMost of the scientific studies and innovations in food packaging have focused on the inhi-bition or prevention of microbial growth as well as avoiding further microbial deteriorationof food products. Among current food packaging techniques, active packaging, particular-ity antimicrobial active packaging, has attracted much attention due to the diversity in thematerials used, the methods of application, and the variety of food products that can be pro-tected. Direct and indirect techniques can be utilized to introduce antimicrobial compoundsinto food packaging materials. The increasing importance of the application of antimicrobialpackaging has inspired a better understanding of these materials and the factors influenc-ing the effectiveness of antimicrobial systems. This article is a review on the materials usedfor delivering antimicrobial substances with a focus on their main mechanisms of actionand release when used for food contact applications. In this regard, the effects of antimi-crobial agents on packaging properties will be discussed. Many challenges, including thecontrolled release of antimicrobial agents and the development of active packaging mate-rials (mainly bio-based materials) with adequate barrier properties, transparency, tensilestrength and other characteristics to meet the requirements of food protection and foodsafety, still remain to be solved in these new approaches to antimicrobial active packaging
Ocratoxina A (OTA), zearalenona (ZEN), desoxinivalenol (DON) e aflatoxina total (TAF) em produtos à base de cereais : revisão sistemática e metanálise
Orientador: Anderson de Souza Sant'AnaTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de AlimentosResumo: Devido a aspectos culturais, religiosos, históricos e econômicos, os cereais e seus derivados foram classificados como produtos alimentícios essenciais em todo o mundo. As micotoxinas são metabólitos secundários produzidos por fungos micotoxigênicos em diferentes alimentos durante as etapas de produção, processamento, transporte e armazenamento. Dentre as mais de 300 micotoxinas identificadas, as mais estudadas em cereais e derivados são ocratoxina A (OTA), zearalenona (ZEN), deoxinivalenol (DON) e aflatoxina (AF). Adicionalmente, o estudo da distribuição, prevalência e concentração das micotoxinas em produtos à base de cereais merece destaque, assim como o efeito que as operações unitárias causam nesses produtos durante o processamento. Diversos estudos têm sido realizados com o objetivo de avaliar a taxa de degradação das micotoxinas em cereais e derivados após processamento convencional e após o uso de novas tecnologias, embora a maioria das micotoxinas possa ser considerada estável durante algumas operações unitárias. Por outro lado, a demanda por métodos analíticos de elevado desempenho tem sido um fator determinante e desafiador na análise de micotoxinas. Além disso, a presença de micotoxinas mascaradas, como o deoxinivalenol-3-glucosídeo (DON-3-Glc) e o deoxinivalenol-15-ß-d-glicopiranosídeo (DON-15-glucoside), pode ser considerada um desafio dentro da área de segurança de alimentos. Nesse contexto, o presente estudo objetivou o desenvolvimento de uma revisão sistêmica e uma meta-análise da prevalência, concentração, impacto das operações unitárias e métodos de identificação utilizados para OTA, ZEN, DON e aflatoxinas totais (AFT) em pães, flocos de milho, cereais matinais, macarrão e outros derivados de cereais a partir da literatura publicada entre 1983 e junho de 2017 disponível em bases de dados como Google Scholar, Scopus e PubMed. A ordem de classificação dos derivados de cereais em relação à prevalência de AFT foi biscoitos > flocos de milho > pães > macarrão > cereais matinais; para DON foi flocos de milho > macarrão > biscoitos > pães > cereais matinais; para OTA foi macarrão ~ pães > flocos de milho > biscoitos > cereais matinais; enquanto que para ZEN foi flocos de milho > pães, cereais matinais > biscoitos > macarrão. Adicionalmente, a classificação geral para a prevalência de micotoxinas em derivados de cereais foi DON > OTA > ZEN > TAF > 15-ADON > 3-ADON. A classificação dos derivados de cereais quanto à concentração de DON foi cereais matinais > pães > biscoitos > macarrão > flocos de milho; ZEN, flocos de milho > pães > cereais matinais > biscoitos > macarrão; AFT, macarrão > flocos de milho > pães > biscoitos > cereais matinais; e para OTA, pães > flocos de milho > cereais matinais > biscoitos > macarrão. A concentração de micotoxinas em produtos à base de cereais seguiu a seguinte classificação: DON > ZEN > 15-ADON > OTA > 3-ADON > AFT. Operações unitárias como moagem e fermentação causaram um aumento na concentração de DON e AFT nesses produtos, enquanto que ocorreu redução na concentração de ZEN e OTA. Embora o processamento térmico (cozimento) provocou uma diminuição em DON, OTA e AFT e um aumento na concentração de ZEN em pães, as concentrações de DON e ZEN foram reduzidas em biscoitos. Entretanto, o cozimento de macarrão causou a redução de DON e o aumento de AFT em macarrão. AFT e DON são as micotoxinas que apresentaram o menor e o maior número de estudos, respectivamente, enquanto que a Alemanha representa o primeiro país a iniciar esses estudos. Além disso, a cromatografia líquida com ionização por eletrospray acoplada à espectrometria de massas (LC-ESI/MS) é a técnica de detecção de micotoxinas mais utilizada. A classificação em relação ao número de estudos envolvendo derivados de cereais é cereais em grãos > flocos de milho > pães > cereais matinais > farinha > produtos infantis > macarrão > outros derivados. Assim, a revisão sistêmica e meta-análise realizadas mostraram que as micotoxinas e o que acontece com elas durante o processamento tem relação direta com as operações unitárias utilizadas na preparação dos diferentes tipos de produtos à base de cereais. Os resultados obtidos no presente trabalho podem ser utilizados em estudos de exposição/análise de risco de micotoxinas visando à geração de medidas com embasamento científico a serem implementadas na cadeia de produção de derivados de cereais a fim de assegurar a saúde públicaAbstract: Due to cultural, religious, historical as well as economic aspects, cereal and cereal-based products were categorized as a crucial group of food products around the world. Mycotoxins are secondary metabolites produced by mycotoxigenic molds in food products during production, processing, transportation, and storage. Among more than 300 identified mycotoxins, ochratoxin A (OTA), zearalenone (ZEN), deoxynivalenol (DON) and aflatoxin (AF) are the most studied in cereal-based products. Also, the study of the distribution, prevalence, and concentration of mycotoxins in cereal products deserves notable attention. In addition, the effect of unit operations during manufacturing on the concentration of mycotoxins was the point of interest. Some investigations were conducted in order to calculate the degradation rate of mycotoxins among the conventional as well as novel procedures used for cereal-based production, although most of the mycotoxins can be considered stable during many processing operations. On the other hand, the demand for well-developed analytical methods as one of the main proposed issues among the mycotoxins analysis can be considered an important challenge. Also, the presence of masked mycotoxins, such as the conjugate deoxynivalenol-3-glucoside (DON-3-Glc) and the deoxynivalenol-15-ß-d-glucopyranoside (DON-15-glucoside), can be accounted as a challenge in food safety. In this context, the current study aimed to perform a systematic review and meta-analysis regarding the prevalence, concentration, impact of unit operations and available identification methods for OTA, ZEN, DON and total aflatoxin (TAF) in bread, cornflakes, breakfast meal, pasta and other cereal-based products among the published literature from 1983 through June 2017 in databases (Google Scholar, Scopus and PubMed). The rank order of cereal-based food products on prevalence of TAF was biscuit > cornflakes > bread > pasta > breakfast cereals; for DON was cornflakes > pasta > biscuit > bread > breakfast cereals; for OTA was pasta ~ bread > cornflakes > biscuit > breakfast cereals; and for ZEN was cornflakes > bread > breakfast cereals > biscuit > pasta. Also, the overall rank order of prevalence of mycotoxins in the cereal foods was DON > OTA > ZEN > TAF > 15-ADON > 3-ADON. The rank order of cereals based food products based on concentration of DON was breakfast cereals > bread > biscuit > pasta > cornflakes; ZEN, cornflakes > bread > breakfast > biscuit > pasta; TAF, pasta > cornflakes > bread > biscuit > breakfast; and OTA, bread > cornflakes > breakfast > biscuit > pasta. The overall rank order of concentration of mycotoxins in the cereal-based products was DON > ZEN > 15-ADON > OTA > 3-ADON > TAF. Some of the investigated processing such as milling and fermentation caused an increase in the concentration of DON and TAF; while reduced the concentration of ZEN and OTA. Although heat processing (cooking) caused a decrease in DON, OTA, and TAF and an increase in the concentration of ZEN in bread, it reduced the concentration of DON and ZEN in the biscuit. However, while cooking of pasta reduced the content of DON, it could increase TAF concentration. The lowest and highest numbers of investigations were associated with TAF and DON in cereal-based products, respectively. Among the countries, Germany was ranked as the first in establishing the investigations. Moreover, the liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI/MS) was categorized as the most implemented technique for mycotoxins detection. The rank order of cereal foods based on number of studies was cereal grain > cornflakes > bread > breakfast > flour > infant product > pasta > other products. The outcomes of this systematic review and meta-analysis showed that the mycotoxins and their fate were influenced differently by the unit operations involved in the preparation of the different cereal-based products. The obtained results of the current study can be used in exposure/risk assessment mycotoxin studies aiming the generation of scientific-based measures to be implemented in the production chain of cereal-based products to safeguard public healthDoutoradoCiência de AlimentosDoutor em Ciência de Alimentos190178/2013-2CNP
The combined effects of ultrasound and lactic acid in inactivating microorganisms on fresh radish (Raphanus raphanistrum subsp. sativus) : microbiological and quality changes
In order to reduce the risk of microbial contamination in fresh radish (Raphanus raphanistrum) and ensure its safety, combined effects of ultrasound and lactic acid in inactivating microorganisms and quality changes of radish were studied. Fresh radish samples were inoculated with Listeria monocytogenes, Escherichia coli, Staphylococcus aureus, and Shigella sonnei separately and were treated with lactic acid (L) 1% and 2%, ultrasound (U) with the amplitude of 0%, 25%, 50%, and 75% for 15 and 30 min and their combination. The quality parameters, including total phenol content, firmness, and total color change, were evaluated on the day of the experiment and after 24 hr of cold storage. Results showed that both applied treatments and their combinations had significant (p < .05) inhibitory effect on all of the studied bacteria. Total phenolic content of the ultrasound treated samples led to higher amounts comparing to other samples. Results showed that using ultrasound power (75%), for 30 min significantly (p < .05) decreased the firmness of samples after 24 hr of cold storage. In conclusion, the application of ultrasound and lactic acid can extend the shelf life of fresh radish8116216
Heterocyclic aromatic amines in doner kebab : quantitation using an efficient microextraction technique coupled with reversed-phase high-performance liquid chromatography
The safety of doner kebab as a traditional Middle East tasty food can threaten via the formation of dangerous compounds such as heterocyclic aromatic amines during heat process. In this regard, the current investigation was devoted to measuring of 4 HAAs (2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), and 2-amino-3-methylimidazo[4,5-f]quinoline (IQ)) in doner kebab samples with an innovative microextraction technique combined with high-performance liquid chromatography. The limit of detection was in the range of 4.8 and 5.3 ng/g, while relative standard deviations were between 6.5% and 8.3%, and recoveries were calculated in the range of 89%-97%. The most and the least total mean values of HAA levels were 13.30 ng/g for MeIQx and 5.0 ng/g for IQ. The proposed method showed a high capability to extract trace amount of HAAs from a complex matrix such as doner kebab. Also, this technique is easy, high sensitive, selective, accurate and efficient81889
The global overview of the occurrence of mycotoxins in cereals: a three-year survey
peer-reviewedMycotoxins are secondary metabolites from molds that can contaminate the food and cause serious health problems in consumers. Aflatoxins, deoxynivalenol, fumonisins, zearalenone, T-2 toxins, ochratoxin A, are mycotoxins with acute carcinogenic, mutagenic, teratogenic, hepatotoxic, estrogenic effects. Cereals are very important and strategic grains that are very susceptible to mycotoxin contamination. In this study, the most recent studies about mycotoxins' occurrence in cereals (wheat, corn, rice, oats, barley, rye, sorghum) from 2018 to 2020 were reviewed. It can be concluded that the majority of the studies in the last three years have been done on corn, wheat, and rice, respectively. According to the results, the hazard of aflatoxin B1 in wheat, corn, and rice is serious as it was higher than the EU limit in most of the studies. Because of climate change globally, the fungal population and mycotoxin patterns in different regions and crops are changing. Therefore, the development of practical control and management strategies is essential to ensure crop safety
A platform independent distributed IPC mechanism in support of programming heterogeneous distributed systems
Abstract Interprocess communication (IPC) is a well-known technique commonly used by programs running on homogeneous distributed systems. However, it cannot be used readily and efficiently by programs running on heterogeneous distributed systems. This is because it must be given a uniform interface either by a set of middleware or more efficiently properly ported to the kernel of all varieties of open source and closed source proprietary operating systems running on heterogeneous nodes of distributed systems. This is particularly problematic to achieve when the kernel code of closed source operating systems are inaccessible to third parties. We propose an alternative nonproprietary approach to enable the use of IPC in heterogeneous distributed systems by wrapping IPC calls from the kernel of closed source operating systems, and converting them into equivalent IPC calls that are efficiently implemented inside the kernel code of open source operating systems. To show the superiority of our approach, we developed a wrapper for converting MS-Windows IPC calls into equivalent Linux IPC calls and benched our approach on a hybrid computer cluster running both types of operating systems
A Systematic Review and Meta-analysis to Investigate the Correlation Vegetable Irrigation with Wastewater and Concentration of Potentially Toxic Elements (PTES): a Case Study of Spinach (Spinacia oleracea) and Radish (Raphanus raphanistrum subsp. sativus)
Water shortage and stress around the world lead to the reuse of wastewater in many sectors while the recycling of water in agriculture as one of the most consumed sectors can boost the contamination of crops by potentially toxic elements (PTEs). Therefore, this study was aimed to investigate the correlation between the accumulation of PTEs (Fe, Zn, Cr, Ni, Cu, Pb, As, Cd, and Se) in edible parts of spinach and radish plants and sewage irrigation by the aid of a meta-analysis. Moreover, the non-carcinogenic risk (N-CR) and carcinogenic risk (CR) for health risk assessment of consumers were assessed through actual total target hazard quotient (TTHQact) and carcinogenic risk (CRact). After the screening process, 51 articles with 75 studies were included. According to findings, the rank order of PTEs in spinach and radish were Fe > Zn > Cr > Cu > Ni > Pb > Cd > As > Se and Fe > Zn > Cr > Ni > Cu > Pb > As > Cd > Se, respectively. PTE adsorption by edible parts of spinach (leafy vegetable) was higher than radish. The health risk assessment shows that residents in Iran, India, and China are at N-CR while the population of Iran, India, and Pakistan are facing CR. © 2020, Springer Science+Business Media, LLC, part of Springer Nature
Assessment of Phenolic Contents and Antioxidant and Antibacterial Activities of Extracts from Four Varieties of Iranian Date Palm (Phoenix dactylifera L.) Seeds
Background and objective: Every year, large quantities of date palm seeds are produced as byproducts in date processing and packaging industries, which is discarded or used as low-value materials for animal feeds and composts. However, these bioresources may include potentials to produce high-value added products in food industries. The major aim of the current study was to assess phenolic profiles and contents and antioxidant and antibacterial activities of four Iranian date palm seed extracts, namely Zahedi, Kabkab, Mazafati and Rabbi.Material and methods: Total phenolic contents, phenolic compounds profile and antioxidant and antibacterial activities of extracts from four Iranian date palm seeds were assessed using Folin-Ciocalteu, reversed-phase high-performance liquid chromatography, 2, 2-diphenyl-1picrylhydrazyl radical scavenging, agar disc diffusion and broth microdilution methods, respectively.Results and conclusion: Total phenolic contents varied 1480-3380 mg GAE 100 g-1 dw. cinnamic, chlorogenic, caffeic and 3, 5-dihydroxybenzoic acid included the primary phenolic compounds, respectively. Of the varieties, Kabkab and Mazafati seed extracts with IC50 values of 16.56 and 22.6 µg ml-1 demonstrated the highest and lowest radical scavenging activity, respectively. Results obtained from disc diffusion method revealed that all extracts included inhibitory effects against Staphylococcus aureus, but not against Escherichia coli. Minimum inhibitory concentration and minimum bactericidal concentration of the extracts ranged 1.563.125 and 3.125-12.5 mg ml-1 for Staphylococcus aureus, respectively. Based on the findings, Iranian date seeds are good sources of extractable phenolic compounds with notable antioxidant activities, which can be used as natural additives in formulations of various products such as functional foods and dietary supplements. Furthermore, these seeds can be converted to value added products through biotechnological processes.Conflict of interest: The authors declare no conflict of interest.
Antibacterial Efficacy of Essential Oils and Sodium Nitrite in Vacuum processed Beef Fillet
Background and Objective: Minimizing the exposure to nitrate and nitrite and therefore reducing the level of potentially carcinogenic nitrosamines is desired due to the strong public demand and political controversy around this issue in many countries. The present study was designed to investigate antibacterial activity of five different types of essential oils alone or in combination with different concentrations of sodium nitrite.Material and Methods: Five types of essential oils Zataria multiflora Boiss, Satureja bachtiarica Bunge, Rosmarinus officinalis L., Mentha pulegium, and Origanum vulgare L were used in the experiments. NaNO2 in concentrations of 0, 100, and 200 mg kg-1 were used to study the growth inhibition of Clostridium spp. inoculated in vacuum processed beef fillet. Essential oils were analyzed by gas chromatography-mass spectrometry. Antimicrobial activity against vegetative cells of Clostridium perfringens and Clostridium sporogenes were primarily done by disc diffusion method and minimum inhibitory concentration of essential oils against vegetative cells were determined by broth macro dilution. Sensory evaluation of the uninoculated cooked vacuum processed beef fillet samples with three essential oils with higher antibacterial activity against the more resistant Clostridium spp. was done.Results and Conclusion: Among the examined Essential oils Satureja bachtiarica Bunge showed the most inhibition effect on Clostridium perfringens (4.1 mg ml-1) and Clostridium sporogenes (5.5 mg ml-1) followed by Zataria multiflora Boiss, Origanum vulgare L., Mentha pulegium and Rosmarinus officinalis L. The antimicrobial activity of essential oils against Clostridium spp. was increased in combination with sodium nitrite. It can therefore be assumed that the combination of these two additives could have significant repercussion in the control of Clostridium perfringens and Clostridium sporogenes in vacuum processed beef fillet samples without compromising the organoleptic properties. The best result was achieved by the combination of 100 mg kg-1 sodium nitrite and 1.1 %v w-1 Satureja Bakhtiarica Bunge which could inhibit the growth of Clostridium species. The results of the current study showed that the essential oils of interest have had drastic effects on clostridium inhibition and could be used in the meat industry especially for sausages due to their impact on technological, microbiological and sensory properties.Conflict of interest: The authors declare no conflict of interest
Postupci proizvodnje propionske kiseline, dosadašnje spoznaje i mogućnosti
During the past years, there has been a growing interest in the bioproduction of propionic acid by Propionibacterium. One of the major limitations of the existing models lies in their low productivity yield. Hence, many strategies have been proposed in order to circumvent this obstacle. This article provides a comprehensive synthesis and review of important biotechnological aspects of propionic acid production as a common ingredient in food and biotechnology industries.
We first discuss some of the most important production processes, mainly focusing on biological production. Then, we provide a summary of important propionic acid producers, including Propionibacterium freudenreichii and Propionibacterium acidipropionici, as well as a wide range of reported growth/production media. Furthermore, we describe bioprocess variables that can have impact on the production yield. Finally, we propose methods for the extraction and analysis of propionic acid and put forward strategies for overcoming the limitations of competitive microbial production from the economical point of view.
Several factors influence the propionic acid concentration and productivity such as culture conditions, type and bioreactor scale; however, the pH value and temperature are the most important ones. Given that there are many reports about propionic acid production from glucose, whey permeate, glycerol, lactic acid, hemicelluloses, hydrolyzed corn meal, lactose, sugarcane molasses and enzymatically hydrolyzed whole wheat flour, only few review articles evaluate biotechnological aspects, i.e. bioprocess variables.U posljednje je vrijeme porastao interes za biološku proizvodnju propionske kiseline s pomoću bakterije Propionibacterium. Glavni nedostatak postojećih modela je slab prinos, zbog čega su predložene različite strategije rješavanja tog problema. U ovom su radu opsežno prikazana bitna biotehnološka obilježja postupaka dobivanja propionske kiseline, jednog od uobičajenih sastojaka u prehrambenoj i biotehnološkoj proizvodnji.
U prvom dijelu opisujemo najznačajnije proizvodne procese, s naglaskom na biološku proizvodnju, a zatim navodimo bakterije koje proizvode propionsku kiselinu, kao što su Propionibacterium freudenreichii i Propionibacterium acidipropionici, te različite podloge za rast ili proizvodnju. Osim toga, opisujemo varijable procesa koje mogu utjecati na prinos. Naposljetku, predlažemo metode ekstrakcije i analize dobivene propionske kiseline, te ističemo strategije pomoću kojih se mogu zaobići ekonomska ograničenja procesa uzrokovana kompeticijom mikroorganizama tijekom proizvodnje.
Na koncentraciju propionske kiseline i produktivnost procesa utječe više čimbenika, kao što su: sastav podloge, tip i veličina bioreaktora te pH-vrijednost i temperatura kao najvažniji čimbenici. Objavljen je velik broj radova o proizvodnji propionske kiseline iz glukoze, permeata sirutke, glicerola, mliječne kiseline, hemiceluloze, hidrolizirane sačme kukuruznih klica, laktoze, melase šećerne trske, te brašna od cjelovitog zrna pšenice hidroliziranog pomoću enzima, ali vrlo mali broj revijalnih prikaza procjenjuje biotehnološke aspekte proizodnje, odnosno varijable bioprocesa
- …