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1.
Compr Rev Food Sci Food Saf ; 22(5): 3765-3789, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37421325

RESUMO

Humans need food processing assuring food safety, quality, and functionality to sustain their life. The ongoing debates regarding food processing require rational and scientific data about food processing and processed foods. This study deals with the importance, origins, and history of processing, defining processes and discussing existing food classification systems and provides recommendations for future food process development. Descriptions and comparisons of technologies for food preservation, their resource efficiency, and beneficial aspects in relation to traditional processing are summarized. Possibilities for pretreatments or combination application and related potentials are provided. A consumer-oriented paradigm change is presented using the potential of resilient technologies for food product improvements rather than the traditional adaptation of raw materials to existing processes. Means for food science and technology research toward dietary changes by transparent, gentle, and resource-efficient processes for consumers food preference, acceptance, and needs are provided.


Assuntos
Manipulação de Alimentos , Alimento Processado , Humanos , Alimentos , Tecnologia de Alimentos , Conservação de Alimentos
2.
Front Nutr ; 10: 912824, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36866052

RESUMO

Introduction: Impact of processing on product characteristics, sustainability, traceability, authenticity, and public health along the food chain becomes more and more important not only to the producer but also to the customer and the trust of a consumer toward a brand. In recent years, the number of juices and smoothies containing so called super foods or fruits, which have been "gently pasteurized," has increased significantly. However, the term "gentle pasteurization" related to the application of emerging preservation technologies such as pulsed electric fields (PEF), high pressure processing (HPP) or ohmic heating (OH) is not clearly defined. Methods: Therefore, the presented study investigated the influence of PEF, HPP, OH, and thermal treatment on quality characteristics and microbial safety of sea buckthorn syrup. Syrups from two different varieties were investigated under the following conditions HPP (600 MPa 4-8 min), OH (83°C and 90°C), PEF (29.5 kV/cm, 6 µs, 100 Hz), and thermal (88°C, hot filling). Analyses to test the influence on quality parameters like ascorbic acid (AA), flavonoids, carotenoids, tocopherols, antioxidant activity; metabolomical/chemical profiling (fingerprinting) via U-HPLC-HRMS/MS (here especially flavonoids and fatty acids); sensory evaluation, as well as microbial stability including storage, were conducted. Results and discussion: Independent from the treatment, the samples were stable over 8 weeks of storage at 4°C. The influence on the nutrient content [Ascorbic acid (AA), total antioxidant activity (TAA), total phenolic compounds (TPC), tocopherols (Vit E)] was similar for all tested technologies. Employing statistical evaluation Principal Component Analysis (PCA) a clear clustering based on the processing technologies was observed. Flavonoids as well as fatty acids were significantly impacted by the type of used preservation technology. This was obvious during the storage time of PEF and HPP syrups, where enzyme activity was still active. The color as well as taste of the syrups were found to be more fresh-like for the HPP treated samples.

3.
Compr Rev Food Sci Food Saf ; 20(4): 3225-3266, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34056857

RESUMO

The last two decades saw a steady increase of high hydrostatic pressure (HHP) used for treatment of foods. Although the science of biomaterials exposed to high pressure started more than a century ago, there still seem to be a number of unanswered questions regarding safety of foods processed using HHP. This review gives an overview on historical development and fundamental aspects of HHP, as well as on potential risks associated with HHP food applications based on available literature. Beside the combination of pressure and temperature, as major factors impacting inactivation of vegetative bacterial cells, bacterial endospores, viruses, and parasites, factors, such as food matrix, water content, presence of dissolved substances, and pH value, also have significant influence on their inactivation by pressure. As a result, pressure treatment of foods should be considered for specific food groups and in accordance with their specific chemical and physical properties. The pressure necessary for inactivation of viruses is in many instances slightly lower than that for vegetative bacterial cells; however, data for food relevant human virus types are missing due to the lack of methods for determining their infectivity. Parasites can be inactivated by comparatively lower pressure than vegetative bacterial cells. The degrees to which chemical reactions progress under pressure treatments are different to those of conventional thermal processes, for example, HHP leads to lower amounts of acrylamide and furan. Additionally, the formation of new unknown or unexpected substances has not yet been observed. To date, no safety-relevant chemical changes have been described for foods treated by HHP. Based on existing sensitization to non-HHP-treated food, the allergenic potential of HHP-treated food is more likely to be equivalent to untreated food. Initial findings on changes in packaging materials under HHP have not yet been adequately supported by scientific data.


Assuntos
Manipulação de Alimentos , Inocuidade dos Alimentos , Bactérias , Humanos , Pressão Hidrostática , Tecnologia
4.
Front Nutr ; 8: 643837, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33829035

RESUMO

Pressure-enhanced sterilization (PES) and ohmic heating (OH) are two emerging sterilization techniques, currently lacking implementation in the food industry. However, both technologies offer significant benefits in terms of spore inactivation using reduced thermal intensity in food products, as well as minimized effects on sensory and nutritional profiles. In this study, PES and OH were tested based on possible food safety process windows in comparison to thermal retorting, to optimize the food quality of carrot-based purees. The following parameters related to food quality were tested: texture, carotenoid content, color, and detectable amount of food processing contaminants (FPC) formed. Application of the innovative sterilization techniques resulted in a better retention of color, texture, and carotenoids (for PES) as well as a reduced formation of food processing contaminants. Importantly, a significant reduction in the formation of furan and its derivates was observed, compared to the retorted samples. Hence, both sterilization technologies showed promising results in the mitigation of potential toxic processing contaminants and retention of quality attributes.

5.
J Colloid Interface Sci ; 596: 173-183, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33839350

RESUMO

HYPOTHESIS: High hydrostatic pressure treatment causes structural changes in interfacial-active ß-lactoglobulin (ß-lg). We hypothesized that the pressure-induced structural changes affect the intra- and intermolecular interactions which determine the interfacial activity of ß-lg. The conducted experimental and numerical investigations could contribute to the mechanistic understanding of the adsorption behavior of proteins in food-related emulsions. EXPERIMENTS: We treated ß-lg in water at pH 7 with high hydrostatic pressures up to 600 MPa for 10 min at 20 °C. The secondary structure was characterized with Fourier-transform infrared spectroscopy (FTIR) and circular dichroism (CD), the surface hydrophobicity and charge with fluorescence-spectroscopy and ζ-potential, and the quaternary structure with membrane-osmometry, analytical ultracentrifugation (AUC) and mass spectrometry (MS). Experimental analyses were supported through molecular dynamic (MD) simulations. The adsorption behavior was investigated with pendant drop analysis. FINDINGS: MD simulation revealed a pressure-induced molten globule state of ß-lg, confirmed by an unfolding of ß-sheets with FTIR, a stabilization of α-helices with CD and loss in tertiary structure induced by an increase in surface hydrophobicity. Membrane-osmometry, AUC and MS indicated the formation of non-covalently linked dimers that migrated slower through the water phase, adsorbed more quickly due to hydrophobic interactions with the oil, and lowered the interfacial tension more strongly than reference ß-lg.


Assuntos
Lactoglobulinas , Óleos , Adsorção , Emulsões , Pressão Hidrostática
6.
Compr Rev Food Sci Food Saf ; 17(3): 646-662, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-33350130

RESUMO

High-pressure thermal sterilization (HPTS) and ultra-high-pressure homogenization (UHPH) are two emerging sterilization techniques that have not been implemented in the food industry yet. The two technologies apply different acting principles as HPTS uses isostatic pressure in combination with heat whereas UHPH uses dynamic pressure in combination with shear stress, cavitation, impingement, and heat. Both technologies offer significant benefits in terms of spore inactivation in food production with reduced thermal intensity and minimized effects on sensory and nutritional profiles. These benefits have resulted in relevant research efforts on both technologies over the past few decades. This state of the art of the discontinuous HPTS-based and the continuous UHPH-based sterilization concepts are assessed within this review. Further, various basic principles and promising future preservation applications of HPTS and UHPH for food processing, that are also applicable in the pharmaceutical, biochemical, and biotechnological sectors, are summarized. In addition, the applications and limitations of these technologies in terms of optimizations needed to overcome the identified challenges are emphasized.

8.
Appl Environ Microbiol ; 83(14)2017 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-28476768

RESUMO

Bacillus and Clostridium species form spores, which pose a challenge to the food industry due to their ubiquitous nature and extreme resistance. Pressurization at <300 MPa triggers spore germination by activating germination receptors (GRs), while pressurization at >300 MPa likely triggers germination by opening dipicolinic acid (DPA) channels present in the inner membrane of the spores. In this work, we expose spores of Bacillus licheniformis, a species associated with food spoilage and occasionally with food poisoning, to high pressure (HP) for holding times of up to 2 h. By using mutant spores lacking one or several GRs, we dissect the roles of the GerA, Ynd, and GerK GRs in moderately HP (mHP; 150 MPa)-induced spore germination. We show that Ynd alone is sufficient for efficient mHP-induced spore germination. GerK also triggers germination with mHP, although at a reduced germination rate compared to that of Ynd. GerA stimulates mHP-induced germination but only in the presence of either the intact GerK or Ynd GR. These results suggests that the effectiveness of the individual GRs in mHP-induced germination differs from their effectiveness in nutrient-induced germination, where GerA plays an essential role. In contrast to Bacillus subtilis spores, treatment with very HP (vHP) of 550 MPa at 37°C did not promote effective germination of B. licheniformis spores. However, treatment with vHP in combination with elevated temperatures (60°C) gave a synergistic effect on spore germination and inactivation. Together, these results provide novel insights into how HP affects B. licheniformis spore germination and inactivation and the role of individual GRs in this process.IMPORTANCE Bacterial spores are inherently resistant to food-processing regimes, such as high-temperature short-time pasteurization, and may therefore compromise food durability and safety. The induction of spore germination facilitates subsequent inactivation by gentler processing conditions that maintain the sensory and nutritional qualities of the food. High-pressure (HP) processing is a nonthermal food-processing technology used to eliminate microbes from food. The application of this technology for spore eradication in the food industry requires a better understanding of how HP affects the spores of different bacterial species. The present study provides novel insights into how HP affects Bacillus licheniformis spores, a species associated with food spoilage and occasionally food poisoning. We describe the roles of different germination receptors in HP-induced germination and the effects of two different pressure levels on the germination and inactivation of spores. This study will potentially contribute to the effort to implement HP technology for spore inactivation in the food industry.


Assuntos
Bacillus licheniformis/crescimento & desenvolvimento , Viabilidade Microbiana , Esporos Bacterianos/química , Bacillus licheniformis/genética , Bacillus licheniformis/metabolismo , Proteínas de Bactérias , Temperatura Alta , Ácidos Picolínicos/metabolismo , Esporos Bacterianos/genética , Esporos Bacterianos/crescimento & desenvolvimento , Esporos Bacterianos/metabolismo
9.
Front Microbiol ; 6: 689, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26217321

RESUMO

Much research has been conducted to comprehend the mechanisms of high pressure (HP) inactivation of spores in aqueous systems but for food model systems these information are scarce. In these systems spores can interact with ingredients which then could possibly lead to retarded or reduced inactivation, which can cause a problem for the sterilization process. The protective mechanism of a reduced a w-value is still unclear. HP processing might prove valuable to overcome protective effects of solutes and achieve shorter process times for sterilization under HP. To gain insight into the underlying mechanisms five a w-values (0.9, 0.92, 0.94, 0.96, 1) were adjusted with two different solutes (NaCl, sucrose). Solutions were inoculated with spores of Bacillus amyloliquefaciens and treated at 105, 110, and 115°C at 600 MPa. Further a thermal inactivation was conducted at the same temperatures for a comparison with the HP data. Afterward, the influence of HP high temperature treatment on the inactivation, the dipicolinic acid (DPA)-release and membrane constitution was assessed by plate count, HPLC and flow cytometry (FCM). The results show that during HP treatments sucrose and salt both have a protective effect, in which the influence of sucrose on the retarded inactivation is higher. The threshold water activities (a w), which is 0.94, here salt and sucrose have a significant influence on the inactivation. The comparison of thermal (105-115°C) and HP and high temperature (600 MPa, 105-115°C) treated samples showed that the time needed to achieve a 4-5 log10 inactivation is reduced from 45 (a w = 1) to 75 (a w = 0.9) min at 105°C to 3 (a w = 1) to 15 (a w = 0.9) minutes at 600 MPa and 105°C. The release of DPA is the rate limiting step of the inactivation and therefore monitoring the release is of great interest. The DPA-release is slowed down in high concentrated solutions (e.g., sucrose, salt) in comparison to a w 1. Since there is a difference in the way the solutes protect the spore it could be seen as an inner spore membrane effect. Maybe as shown for vegetative microorganism the solutes can interact with membranes, e.g., the inner spore membrane. Flow cytometry (FCM) measurement data show a similar trend.

10.
Food Microbiol ; 46: 184-194, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25475283

RESUMO

Enterohemorrhagic Escherichia coli strains cause each year thousands of illnesses, which are sometimes accompanied by the hemolytic uremic syndrome, like in the 2011 outbreak in Germany. For preservation thermal pasteurization is commonly used, which can cause unwanted quality changes. To prevent this high pressure treatment is a potential alternative. Within this study, the 2011 outbreak strain O104:H4, an O157:H7 and a non-pathogenic strain (DSM1116) were tested. The cells were treated in buffer (pH 7 and pH 5) and carrot juice (pH 5.1) in a pressure temperature range of 0.1-500 MPa and 20-70 °C. Flow cytometry was used to investigate the pressure impact on cell structures of the strain DSM1116. Both pathogenic strains had a much higher resistance in buffer and carrot juice than the non-pathogenic surrogate. Further, strains cultivated and treated at a lower pH-value showed higher pressure stability, presumably due to variations in the membrane composition. This was confirmed for the strain DSM1116 by flow cytometry. Cells cultivated and treated at pH 5 had a stronger ability to retain their membrane potential but showed higher rates of membrane permeabilization at pressures <200 MPa compared to cells cultivated and treated at pH 7. These cells had the lowest membrane permeabilization rate at around 125 MPa, possibly denoting that variations in the fatty acid composition and membrane fluidity contribute to this stabilization phenomenon.


Assuntos
Bebidas/microbiologia , Infecções por Escherichia coli/microbiologia , Escherichia coli Shiga Toxigênica/crescimento & desenvolvimento , Bebidas/análise , Surtos de Doenças , Infecções por Escherichia coli/epidemiologia , Escherichia coli O157/química , Escherichia coli O157/crescimento & desenvolvimento , Alemanha/epidemiologia , Humanos , Concentração de Íons de Hidrogênio , Viabilidade Microbiana , Pressão , Escherichia coli Shiga Toxigênica/química
11.
J Food Sci ; 79(2): M230-7, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24547697

RESUMO

The benefits that high-pressure thermal sterilization offers as an emerging technology could be used to produce a better overall food quality. Due to shorter dwell times and lower thermal load applied to the product in comparison to the thermal retorting, lower numbers and quantities of unwanted food processing contaminants (FPCs), for example, furan, acrylamide, HMF, and MCPD-esters could be formed. Two spore strains were used to test the technique; Geobacillus stearothermophilus and Bacillus amyloliquefaciens, over the temperature range 90 to 121 °C at 600 MPa. The treatments were carried out in baby food puree and ACES-buffer. The treatments at 90 and 105 °C showed that G. stearothermophilus is more pressure-sensitive than B. amyloliquefaciens. The formation of FPCs was monitored during the sterilization process and compared to the amounts found in retorted samples of the same food. The amounts of furan could be reduced between 81% to 96% in comparison to retorting for the tested temperature pressure combination even at sterilization conditions of F0-value in 7 min.


Assuntos
Bacillus/crescimento & desenvolvimento , Qualidade dos Alimentos , Alimentos em Conserva/microbiologia , Geobacillus stearothermophilus/crescimento & desenvolvimento , Alimentos Infantis/microbiologia , Esterilização , Verduras/microbiologia , Bacillus/isolamento & purificação , Bacillus/fisiologia , Contaminação de Alimentos/prevenção & controle , Conservação de Alimentos , Alimentos em Conserva/análise , Furanos/análise , Furanos/química , Geobacillus stearothermophilus/isolamento & purificação , Geobacillus stearothermophilus/fisiologia , Alemanha , Temperatura Alta/efeitos adversos , Humanos , Lactente , Alimentos Infantis/análise , Cinética , Viabilidade Microbiana , Modelos Biológicos , Mutagênicos/análise , Mutagênicos/química , Pressão , Esporos Bacterianos/crescimento & desenvolvimento , Esporos Bacterianos/isolamento & purificação , Esporos Bacterianos/fisiologia , Verduras/química
12.
J Autism Dev Disord ; 33(3): 349-54, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12908837

RESUMO

Behavioral side effects associated with clonazepam may include agitation, aggression, hyperactivity, irritability, property destruction, and temper tantrums. These side effects may be inadvertently confused with other behavioral or psychiatric conditions, especially if exacerbation of existing challenging behavior occurs. This report describes an individual with mental retardation who experienced behavioral exacerbation associated with clonazepam prescribed at 2 mg/day (0.02 mg/kg/day) to treat aggression, self-injurious behavior, property destruction, and screaming, which was measured with a 15-minute partial interval recording measurement method. When clonazepam was reduced and discontinued, these behaviors significantly decreased from 3.1% of intervals (95% confidence band = 1.6% to 4.6%) to 0.1% of intervals (95% confidence band = 0% to 0.1%). Indicators suggesting review by appropriate medical personnel for possible clonazepam behavioral side effects are provided.


Assuntos
Anticonvulsivantes/efeitos adversos , Clonazepam/efeitos adversos , Deficiência Intelectual/tratamento farmacológico , Deficiência Intelectual/psicologia , Transtornos Mentais/etiologia , Agressão , Humanos , Masculino , Pessoa de Meia-Idade , Comportamento Autodestrutivo/etiologia
13.
Am J Ment Retard ; 107(5): 376-410, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12186578

RESUMO

Behavioral side effects associated with benzodiazepines (such as clonazepam, diazepam, and lorazepam) are an easily overlooked and underrecognized problem with individuals who have mental retardation and can be inadvertently confused with other behavioral or psychiatric conditions. Based upon a literature review, behavioral side effects occurred for 13.0% of 446 individuals with mental retardation who were prescribed benzodiazepines for either behavioral or psychiatric conditions (n = 138, 17.4%), epilepsy (n = 208, 15.4%), or other medical conditions such as myoclonus or cerebral palsy (n = 100, 2.0%). Behavioral side effects for individual benzodiazepines for which data were available ranged from 11.4% to 25.0%. Implications of nonrecognition are discussed, and clinical indicators suggesting review by appropriate medical personnel are provided.


Assuntos
Agressão/efeitos dos fármacos , Ansiolíticos/efeitos adversos , Deficiência Intelectual/tratamento farmacológico , Transtornos Mentais/induzido quimicamente , Adolescente , Adulto , Ansiolíticos/uso terapêutico , Benzodiazepinas , Ensaios Clínicos como Assunto , Relação Dose-Resposta a Droga , Interações Medicamentosas , Humanos , Deficiência Intelectual/psicologia , Transtornos Mentais/diagnóstico , Transtornos Mentais/psicologia
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