| 1. |
- Anker, M., et al.
(författare)
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Improved water vapor barrier of whey protein films by addition of an acetylated monoglyceride
- 2002
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Ingår i: Innovative Food Science & Emerging Technologies. - 1466-8564 .- 1878-5522. ; 3:1, s. 81-92
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Tidskriftsartikel (refereegranskat)abstract
- This study aimed to determine to what extent the water-vapor barrier of whey protein isolate (WPI) films could be improved by adding a lipid and make laminate and emulsion films. The laminate whey protein-lipid film decreased the water vapor permeability (WVP) 70 times compared with the WPI film. The WVP of the emulsion films was half the value of the WPI film and was not affected by changes in lipid concentration, whereas an increased homogenization led to a slight reduction in WVP. The mechanical properties showed that the lipid functioned as an apparent plasticizer by enhancing the fracture properties of the emulsion films. This effect increased with homogenization. The maximum strain at break was 117% compared with 50% for the less-homogenized emulsion films and 20% for the pure WPI films. Phase-separated emulsion films were produced with a concentration gradient of fat through the films, but pure bilayer films were not formed. © 2002 Elsevier Science Ltd. All rights reserved.
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| 2. |
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| 3. |
- Aronsson, Kristina, et al.
(författare)
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Inactivation of microorganisms using pulsed electric fields : The influence of process parameters on Escherichia coli, Listeria innocua, Leuconostoc mesenteroides and Saccharomyces cerevisiae
- 2001
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Ingår i: Innovative Food Science & Emerging Technologies. - 1466-8564 .- 1878-5522. ; 2:1, s. 41-54
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Tidskriftsartikel (refereegranskat)abstract
- This study examines the killing effect of pulsed electric fields (PEF) on four organisms suspended in a model medium. Escherichia coli, Listeria innocua, Leuconostoc mesenteroides and Saccharomyces cerevisiae differ in size, shape and cell wall construction. The electric field strength, pulse duration and number of pulses were varied in the ranges of 25-35 kV/cm, 2-4 ?s and 20-40 pulses, respectively. The results showed that S. cerevisiae was the most sensitive organism with a 6-log reduction, followed by E. coli with a 5.4-log reduction, when they were exposed to 30 kV/cm, and 20 pulses with 4 ?s duration. The most resistant organisms were L. innocua and L. mesenteroides with only a 3-log reduction, however, by increasing the parameters to 35 kV/cm and 40 pulses with 4 ?s pulse duration; marked viability reductions of 8 and 7 log, respectively, were observed. Heat, which is generated during the process, has limited killing effect on the cells, hence the observed reduction can be ascribed to the PEF treatment. Although transmission electron microscopy of PEF treated cells did not confirm membrane damage, observations suggest that PEF treatments have profound direct or indirect effects on the intracellular organisation of microorganisms. © 2001 Elsevier Science Ltd.
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| 4. |
- Aronsson, Kristina, et al.
(författare)
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Influence of pH, water activity and temperature on the inactivation of Escherichia coli and Saccharomyces cerevisiae by pulsed electric fields
- 2001
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Ingår i: Innovative Food Science & Emerging Technologies. - 1466-8564 .- 1878-5522. ; 2:2, s. 105-112
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to examine the influence of pH, water activity (aw) and temperature on the killing effect of pulsed electric fields (PEF). Escherichia coli and Saccharomyces cerevisiae suspended in a model media were subjected to 20 pulses with 4 ?s duration in a continuous PEF system, during which the effects of pH (4.0-7.0), aw (1.00-0.94) and inlet temperature (10°C and 30°C) could easily be studied. Electrical field strengths were set to 25 kV/cm for S. cerevisiae and 30 kV/cm for E. coli and the highest outlet temperature was monitored to 44°C. A synergy of low pH values, high temperatures and PEF processing was observed. A drop in pH value from 7.0 to 4.0 resulted in the reduction of E. coli by four additional log units, whereas for S. cerevisiae, the pH effect was less pronounced. Lowering aw seems to protect both E. coli and S. cerevisiae from PEF processing. © 2001 Elsevier Science Ltd.
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| 5. |
- Lindgren, M., et al.
(författare)
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Simulation of the temperature increase in pulsed electric field (PEF) continuous flow treatment chambers
- 2002
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Ingår i: Innovative Food Science & Emerging Technologies. - 1466-8564 .- 1878-5522. ; 3:3, s. 233-245
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Tidskriftsartikel (refereegranskat)abstract
- The application of intense pulsed electric fields (PEF) in foods is intended to be a non-thermal method to inactivate microorganisms. However, it is well known that an increase in temperature is present in this process due to ohmic heating, where the pulsed electric field energy input is transformed into heat. The aim of this study was to investigate the computer modeled temperature increase in the outflow for different flow-through PEF treatment chamber designs. Given equal experimental conditions, the temperature increase is indicative of the PEF dose, and a more uniform temperature profile is thus indicative of a more homogeneous PEF treatment. The radial distribution of the temperature increase was simulated in computer models of four different chambers. The temperature increase was found to be more homogeneous in the treatment chambers making use of a decrease in the insulator diameter, i.e. a design letting the insulators and electrodes intersect at angles close to 90°. The maximum temperature increase was found close to the wall, where the flow velocity is low. Cooling of the electrodes and electric insulators is recommended to avoid too high a temperature increase. The minimum temperature increase found was 29% of the calculated average in the worst case studied here. The minimum PEF dose to which the food was subjected would thus is less than the intended dose, since the food clearly was not subjected to the intended electric field strength during the intended exposure time. This is an important result in terms of food safety in the sense that a minimum PEF treatment should be guaranteed. The microbiological inactivation was experimentally evaluated using two of the treatment chamber designs. The result is consistent with the simulations and shows a small increase in inactivation and less needed energy input giving less average temperature increase for the chamber implementing a contraction of the diameter of the insulating spacer. © 2002 Elsevier Science Ltd. All rights reserved.
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| 6. |
- Vardakou, M., et al.
(författare)
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Synergy between enzymes involved in the degradation of insoluble wheat flour arabinoxylan
- 2004
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Ingår i: Innovative Food Science & Emerging Technologies. - 1466-8564 .- 1878-5522. ; 5:1, s. 107-112
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Tidskriftsartikel (refereegranskat)abstract
- Two microbial endo-β-1,4-xylanases (EXs, EC 3.2.1.8) belonging to glycanase families 10 and 11 were examined for their ability to release ferulic acid (FA) from water-unextractable arabinoxylan (WU-AX) in the presence of a feruloyl esterase (FoFAE-II) from Fusarium oxysporum. WU-AX was incubated with different levels of a Thermoascus aurantiacus family 10 (XYLI) and a Sporotrichum thermophile family 11 (XYLA) endoxylanases. At 10 g/l arabinoxylan, enzyme concentrations (KE values) needed to obtain half-maximal hydrolysis rates for FA release were 0.18 and 0.44 nM for the xylanases from T. aurantiacus and S. thermophile, respectively. Determination of Vmax/KE revealed that the family 10 enzyme performed 4.3 times more efficiently than the family 11 enzyme in liberation of FA when a feruloyl esterase is present. Molecular weights of the products formed were assessed and separation of feruloyl-oligosaccharides was achieved by anion-exchange and size-exclusion chromatography (SEC). The results showed that the degradation of the xylan backbone was influenced strongest by the action of xylanases while the presence of the esterase mainly resulted in the release of ferulic acid from the produced short chain feruloylated xylo-oligosaccharides by the action of xylanases
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| 7. |
- Al-Naamani, Laila, et al.
(författare)
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Chitosan-zinc oxide nanoparticle composite coating for active food packaging applications
- 2016
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Ingår i: Innovative Food Science & Emerging Technologies. - : Elsevier. - 1466-8564 .- 1878-5522. ; 38, s. 231-237
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Tidskriftsartikel (refereegranskat)abstract
- In this study antimicrobial properties of chitosan and chitosan-zinc oxide (ZnO) nanocomposite coatings on PE films were studied. Oxygen plasma pretreatment of PE films led to increased adhesion by 2% of chitosan and the nanocomposite coating solutions to the packaging films. Scanning Electron Microscopy (SEM) revealed uniform coatings on PE surfaces. Incorporation of ZnO nanoparticles into the chitosan matrix resulted in 42% increase in solubility; swelling decreased by 80% while the water contact angle (WCA) increased from 60 to 95 compared to chitosan coating. PE coated with chitosan-ZnO nanocomposite films completely inactivated and prevented the growth of food pathogens, while chitosan-coated films showed only 10-fold decline in the viable cell counts of Salmonella enterica, Escherichia coli and Staphylococcus aureus after 24-h incubation compared to the control. Industrial relevance: One of the greatest challenges of food industry is microbial contamination. The present study suggests that PE coating with chitosan-ZnO nanocomposite is a promising technique to enhance antimicrobial properties of the films. Chitosan-ZnO nanocomposite coatings improved antibacterial properties of PE by inactivating about 99.9% of viable pathogenic bacteria. Hence, our results show the effectiveness of the nanocomposite coating in the development of active food packaging in order to prolong the shelf life of food products.
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| 8. |
- Ceresino, Elaine Berger, et al.
(författare)
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Processing conditions and transglutaminase sources to "drive" the wheat gluten dough quality
- 2020
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Ingår i: Innovative Food Science & Emerging Technologies. - : Elsevier BV. - 1466-8564 .- 1878-5522. ; 65
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Tidskriftsartikel (refereegranskat)abstract
- Gluten proteins are highly impacting the quality of various gluten-based products, and transglutaminases (TGs) are used to influence the protein cross-linking. In this study we monitored the interplay of "harsh" and "mild" gluten processing for dough mixing and pasta-like sheet production and TGs from a commercial and newly sourced bacteria (SB6). Despite the harshly separated gluten presenting strongly cross-linked proteins in the beginning of the mixing, similar levels of polymerization were achieved at the optimum mixing time but with differences in the secondary protein structure. TG addition increased polymerization in wheat doughs, possibly as a result of increased glutenin polymerization, while gliadins become more soluble with SB6. This enzyme also dramatically increased polymerization in mild gluten. These results show that an adequate investigation when using TGs and gluten from various origins is necessary to adequately predict the quality in various gluten-based products, thus, of great relevance to the food industry. Industrial relevance: Currently, there is a mounting trend towards the modification of gluten proteins to improve technological features and functionality. In breadmaking, when weak Hour (low protein content) is used or general stabilization is desired for technological purposes, additives can be used to stabilize the gluten protein matrix. The use of transglutaminase (TG) has grown in popularity as they promote specific cross-linking between residues of glutamine and lysine in proteins. Another way of improving dough functionality is by increasing the oxidation of disulfide groups by adding gluten which is a co-product of the starch industry. Industrial production of gluten includes the use of heating and shear forces, which may impact gluten dough-forming ability. Thus, increased understanding of the interplay of gluten processing and the impact of choice of the TG origin in gluten dough quality is highly applicable in food industry.
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| 9. |
- Flynn, Katherine M., et al.
(författare)
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Ideal skills for European food scientists and technologists : Identifying the most desired knowledge, skills and competencies
- 2013
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Ingår i: Innovative Food Science & Emerging Technologies. - : Elsevier BV. - 1466-8564 .- 1878-5522. ; 18, s. 246-255
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Tidskriftsartikel (refereegranskat)abstract
- Training food scientists and technologists (FSTs) to have appropriate skills begins with identification of those skills most desired by employers. Between March 2010 and August 2011, 16 workshops in 16 countries had 315 local FST employers contribute ideas of skills desired in their FSTs. Attendees provided as many skills as possible and these descriptive data were quantifed and then analysed with multiple contingency tables and chi squared testing. Of the 3348 skill ideas provided, the most desired skill overall was Communicating, which was identified 13% of the time. Separate analysis of the 792 food sector skills indicated Product Development, at 28%, as the most desired. Geographical region, employment area and FST level of responsibility all significantly influenced the top 3 choices of overall skills and of food sector skills, indicating that most desired skills in the food industry are not uniform. These results should contribute to the improvement of FST training and thus benefit the European food industry. Industrial relevance: The data presented here suggest that improvements in FST training, particularly the acquisition of 'soft skills', will improve Europe's food workforce as these are the skills employers most desire. These data further suggest that geographical region significantly influences those skills most desired by industrial employers. Differences in desired skills at different levels of FST responsibility further suggest that continual FST training i.e., continual professional development, will contribute to improved FST performance. Overall, this study presents data which can improve FST performance and thus contribute to increased innovation and competitiveness of the food and drink industry.
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| 10. |
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| 11. |
- Kerbstadt, Sebastian, et al.
(författare)
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Effect of novel drying techniques on the extraction of anthocyanins from bilberry press cake using supercritical carbon dioxide
- 2015
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Ingår i: Innovative Food Science & Emerging Technologies. - : Elsevier BV. - 1466-8564 .- 1878-5522. ; 29, s. 209-214
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Tidskriftsartikel (refereegranskat)abstract
- The objective of this study was to assess the effect of novel drying techniques on the total anthocyanin content of extracts from bilberry press cake using supercritical carbon dioxide with ethanol as co-solvent. Prior to extraction, bilberry press cake was dried at 40 °C and 70 °C to moisture contents of 6% and 20% (w/w) by infrared drying, infrared impingement drying, and microwave-assisted hot-air drying and compared to freeze drying. The total anthocyanin content of extracts varied in the range of 13.67 ± 0.25 mg/g dry weight to 43.66 ± 0.79 mg/g dry weight, dependent on the choice of drying technique, temperature, and moisture content. Bilberry press cake treated with infrared impingement drying at 70 °C to 20% (w/w) moisture content resulted in the highest total anthocyanin content of extracts. The findings of this study show the importance in combining supercritical carbon dioxide extraction with an appropriate drying technique.Industrial relevanceSupercritical carbon dioxide extraction is a green technology that offers mild extraction conditions for sensitive compounds. Drying prior to the extraction is usually necessary and may limit the extraction efficiency by degrading sensitive compounds or influencing the matrix and thereby the release of solute in the subsequent extraction step. More knowledge about the effect of different drying techniques on the extraction efficiency is of industrial interest to optimize both the yield and quality of extracts.
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| 12. |
- Lemmens, L., et al.
(författare)
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Thermal pretreatments of carrot pieces using different heating techniques: Effect on quality related aspects
- 2009
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Ingår i: Innovative Food Science and Emerging Technologies. - : Elsevier BV. - 1466-8564 .- 1878-5522. ; 10:4, s. 522-529
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Tidskriftsartikel (refereegranskat)abstract
- During fruit and vegetable processing, different thermal processes (blanching, pasteurization, sterilization) based on different heating techniques can be used. In this context, it is important to evaluate the impact of blanching on quality related parameters. This paper describes a case study on carrot pieces, studying the effect of thermal pretreatments (high temperature blanching, low temperature blanching and low temperature blanching in combination with Ca 2+ -soaking) on enzyme activity (peroxidase (POD), pectinmethylesterase (PME)), structural properties (degree of methoxylation (DM), texture) and nutritional aspects (β-carotene content). The thermal pretreatments were carried out by conventional heating as well as by microwave heating and ohmic heating, since these new heating methods can become important new technologies in food industry. It has been shown that, depending on the application, selecting the right pretreatment conditions can help to control the enzyme activity. To obtain a firm carrot texture after thermal processing, low temperature blanching seems to be the most appropriate pretreatment condition. This was supported by the micrographs and the analysis of the degree of methoxylation. Furthermore almost no influence of the pretreatments on the β-carotene content of the samples could be noticed. For all quality parameters studied, no unambiguous effect of the heating technique could be detected. Thus, the time/temperature conditions of the thermal pretreatments determine the quality related aspect s, independent of the heating technique used. Industrial relevance: With regard to consumer acceptance, a good quality control of fruit and vegetables is important. Food quality covers a wide range of parameters, including enzyme content, structural properties, nutritional properties, sensorial characteristics etc. This study gives an overview of the effect of blanching, which is a common preprocessing step in food processing, on quality related parameters in carrots. The data deliver integrated information on structural level as well as on nutritional level and on enzyme content. Moreover, novel thermal process technologies (microwave heating, ohmic heating), which gain more and more attention in food industry, are being considered as alternatives for conventional blanching. © 2009 Elsevier Ltd. All rights reserved.
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| 13. |
- Leth, S., et al.
(författare)
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A feasibility study of the use of a SIRE biosensor in the monitoring of H2O2 added to milk samples. : A possible new technology for early detection of mastitis?
- 2004
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Ingår i: Innovative Food Science & Emerging Technologies. - : Elsevier BV. - 1466-8564 .- 1878-5522. ; 5:4, s. 515-522
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Tidskriftsartikel (refereegranskat)abstract
- Mastitic milk is known to degrade hydrogen peroxide at a higher rate than milk from healthy cows due to increased enzymatic, i.e. catalase, activity. This work deals with a feasibility study of a new method for monitoring hydrogen peroxide degradation in milk based on the electrochemical detection of hydrogen peroxide. This technology could be implemented in-line with the milking equipment at farms. A low pasteurised (75 °C/15 s), non-homogenised milk was chosen as a model for fresh milk. Milk samples were spiked with catalase (0.53-5.33 U/ml). Given that H2O2 as a parameter allows for the early indication of mastitis (in itself or in combination with other measurements), we believe that the SIRE technology could be developed further to meet the analytical requirements of such a detection system. © 2004 Elsevier Ltd. All rights reserved.
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| 14. |
- Lukitawesa, Lukitawesa, et al.
(författare)
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Semi-continuous production of volatile fatty acids from citrus waste using membrane bioreactors
- 2021
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Ingår i: Innovative Food Science & Emerging Technologies. - : Elsevier BV. - 1466-8564 .- 1878-5522.
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Tidskriftsartikel (refereegranskat)abstract
- In the production of volatile fatty acids (VFAs) from citrus waste, organic loadings rates (OLR) from 1 to 8 g VS/L·d were applied in semi-continuous anaerobic fermentation using a tubular membrane bioreactor (MBR). Filtration fluxes of the membrane were in the range of 7.9–8.5 L/m2·h. trans-Membrane pressure (TMP) revolved around 24.1–67.5 mbar. No obvious fouling and clogging occurred. The highest yield of VFAs 0.67 g VFA/g VS (volatile solids) was achieved at OLR 4 g VS/L·d. When citrus waste was pretreated to remove D-limonene using an airlift reactor, the highest yield of VFAs 0.84 g VFA/g VS was also obtained at OLR 4 g VS/L·d. A further increase in OLR of up to 8 g VS/L·d caused a sharp decrease in yield for the untreated citrus waste and only marginal changes were observed for the pretreated citrus waste. The main composition of VFAs was acetate, butyrate, caproate, and propionate. © 2020 Elsevier Ltd
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| 15. |
- Marques, Tatiana M., 1980-, et al.
(författare)
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Gut microbiota modulation and implications for host health: dietary strategies to influence the gut-brain axis
- 2013
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Ingår i: Innovative Food Science & Emerging Technologies. - : Elsevier. - 1466-8564 .- 1878-5522. ; 22, s. 239-247
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Tidskriftsartikel (refereegranskat)abstract
- The human intestinal microbiota evolves from an immature and unstable ecosystem during infancy into a more complex and stable ecosystem in adulthood. Diet is one of the main factors contributing to the composition and diversity of the human intestinal microbiota. From birth, breast milk offers the best nutritional regime for maturation of the gut, whereas the introduction of solid food selects the most adapted bacteria, converging towards an adult-like microbiota. The gut microbiota plays an important role in host health, influencing the maturation of the immune system and regulating energy metabolism. Moreover, it has become evident that the microbiota can affect brain function and behaviour. On this bidirectional communication between intestine and the central nervous system (CNS), the so called gut-brain axis, the gut influences brain development and biochemistry, whereas the brain affects gastrointestinal function. In this context, probiotics and prebiotics have been used as dietary strategies aimed at improving host health by modulating the gut ecosystem and, consequently, affecting host stress-responses, behaviour and cognition.
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| 16. |
- Pettersson, A., et al.
(författare)
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A hygienically designed force gripper for flexible handling of variable and easily damaged natural food products
- 2011
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Ingår i: Innovative Food Science & Emerging Technologies. - : Elsevier BV. - 1466-8564 .- 1878-5522. ; 12:3, s. 344-351
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Tidskriftsartikel (refereegranskat)abstract
- To overcome present difficulties in robotized food handling a force sensing robot gripper for flexible production is presented. A magnetic coupling is used to completely encapsulate the actuator mechanism, improving hygiene and enabling a future hose-down proof design. Product location, orientation and product type and width are extracted by a vision system to aid the gripping process. Knowing the product type the grip force is set individually for each product. In the paper data of achievable grip strength, positioning accuracy and gripping times for force controlled gripping are presented. Grip times of 410-530 ms for grip forces of 50-700 g respectively are realized. An initial microbiology study on a model system showed that an intermediate decontamination can be used to reduce the cross contamination of Listeria innocua (SIK215) significantly. The gripper is further shown to be able to handle an in-feed mixture of tomatoes, apples, carrots, broccoli and grapes without intermediate adjustments. Industrial relevance: This paper covers the development and evaluation of a hygienically designed universal robot food gripper. The gripper enables an increased use of robots in the food industry and makes very flexible production with minimal changeover times possible. © 2011 Elsevier Ltd. All rights reserved.
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| 17. |
- Semenoglou, Ioanna, et al.
(författare)
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Supercritical CO2 extraction of oil from Arctic charr side streams from filleting processing
- 2021
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Ingår i: Innovative Food Science & Emerging Technologies. - : Elsevier Ltd. - 1466-8564 .- 1878-5522. ; 71
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Tidskriftsartikel (refereegranskat)abstract
- Although Arctic charr side streams contain limited amounts of fish flesh, they are a rich fish oil source (46.3 ± 0.6%). The aim of the study was to investigate the potential for valorization of Arctic charr filleting side streams through the extraction of oil by supercritical CO2 technology. The effect of temperature (40 °C and 80 °C) and pressure (20, 35 and 45 MPa) on the final extract after supercritical fluid extraction (SFE) was evaluated. Temperature increase enhanced the yield but decreased the antioxidant activity at 45 MPa, did not affect the yield and the antioxidant activity at 35 MPa, whereas yield was limited at 20 MPa and 80 °C. Extracts were rich in monounsaturated fatty acids (56.7–58.3%, especially oleic acid 37.2–38.0%), and polyunsaturated fatty acids (20.2–26.1%, especially DHA 7.3–11.4%). The presence of astaxanthin significantly preserved the extracts from oxidation. Industrial relevance: Supercritical carbon dioxide extraction is a green technology appropriate for the recovery of non-polar and heat sensitive compounds. The extracted Arctic charr oils were rich in polyunsaturated fatty acids and astaxanthin which inhibited oxidation in combination with the absence of oxygen and light during the process. This technology could be an excellent alternative for more sustainable valorization of fish processing side streams. © 2021 The Author(s)
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| 18. |
- Xanthakis, Epameinondas, et al.
(författare)
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Effect of microwave assisted blanching on the ascorbic acid oxidase inactivation and vitamin C degradation in frozen mangoes
- 2018
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Ingår i: Innovative Food Science & Emerging Technologies. - : Elsevier BV. - 1466-8564 .- 1878-5522. ; 48, s. 248-257
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Tidskriftsartikel (refereegranskat)abstract
- The effect of microwave assisted and conventional water blanching of mango (Mangifera indica) under two different blanching scenarios, High Temperature Short Time (HTST) and Low Temperature Long Time (LTLT) on ascorbic acid oxidase (AAO) inactivation and on vitamin C (L-ascorbic acid & dehydroascorbic acid) retention were comparatively studied. The impact of alternative blanching processes and subsequent frozen storage on enzymatic inactivation and vitamin C was kinetically modelled. Both water and microwave HTST as well as LTLT microwave treatments of mango pieces showed high degree of AAO inactivation. An approximately 30% residual AAO activity was observed and was described through a first order fractional conversion model. Microwave assisted blanching led to higher retention of total vitamin C in both LTLT and HTST treatments. In LTLT water blanching, vitamin C loss was mainly caused by mass transfer phenomena rather than temperature degradation, while after HTST treatments the decrease of total vitamin C content seemed to be mainly related to thermal degradation than due to the leakage of the nutrients in the blanching medium. Further inactivation of the thermostable fraction of AAO and degradation of total vitamin C were observed after frozen storage for 130 days at −18.63 ± 0.48 °C.
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| 19. |
- Dymek, Katarzyna, et al.
(författare)
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Modeling electroporation of the non-treated and vacuum impregnated heterogeneous tissue of spinach leaves
- 2015
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Ingår i: Innovative Food Science & Emerging Technologies. - : Elsevier BV. - 1466-8564. ; 29, s. 55-64
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Tidskriftsartikel (refereegranskat)abstract
- Uniform electroporation of the heterogeneous structure of spinach leaf cross section is a technological challenge that is addressed in this investigation. Three dimensional models were created with cells arranged in specific tissue types, considering a leaf with its air fraction and a leaf where the air fraction was replaced by a solution of known properties using vacuum impregnation. The models were validated before electroporation, in the frequency domain, where alternating voltage and current signal at frequencies from 20 Hz to I MHz were used to measure conductivity of the tissue. They were also validated through measurements of current during electroporation when a single 250 mu s rectangular pulse with amplitudes ranging from 50 to 500 V was applied. Model validations show that both the frequency dependent conductivity and electroporation are well predicted. The importance of the wax layer and stomata in the model is thoroughly discussed. Industrial relevance: Our aim was to investigate electroporation of the spinach leaf by developing a model which would enable us to meet the technological challenge of achieving uniform electroporation in a highly heterogeneous structure in the context of a process aimed at improving freezing stability of plant foods. Pulsed electric field treatment may be used to introduce the cryoprotectant molecules into the cells, and hence improve the structure and properties of frozen food plants. (C) 2014 Elsevier Ltd. All rights reserved.
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| 20. |
- Hoac, Tien, et al.
(författare)
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Influence of heat treatment on lipid oxidation and glutathione peroxidase activity in chicken and duck meat
- 2006
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Ingår i: Innovative Food Science & Emerging Technologies. - : Elsevier BV. - 1466-8564. ; 7:1-2, s. 88-93
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Tidskriftsartikel (refereegranskat)abstract
- To study the role of glutathione peroxidase for lipid oxidation in meat, chicken and duck muscle were heated to an internal temperature of 60, 70 or 80 degrees C and the meats were then stored at 8 degrees C for up to 6 days. Thiobarbituric-acid-reactive substances (TBARS) and glutathione peroxidase (GSHPx) activity were measured on days 0, 1, 3 and 6. In heated muscle samples, TBARS increased during 6 days of storage. GSHPx activity was diminished with increasing temperature and was much more affected by the internal temperature than by the length of the subsequent cold storage, whereas the formation of TBARS was affected by both the final temperature and storage time. Meat samples, which had been heated to 80 degrees C, were also used to investigate the effect of added GSHPx on lipid oxidation. GSHPx (2 or 4 U) was added per I g meat after cooking, and the concentration of TBARS and GSHPx activity were measured on day 0 and 6. Chicken muscle samples with added GSHPx had a lower TBARS concentration on day 6 (2 U/g meat: 58% and 4 U/g meat: 54%) compared to the control without added GSHPx. In contrast, GSHPx addition had no effect on lipid oxidation in heated duck muscle. The study shows that there was a reciprocal relationship between TBARS formation and GSHPx activity and that addition of GSHPx could decrease lipid oxidation. (c) 2006 Elsevier Ltd. All rights reserved.
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| 21. |
- Kanafusa, Sumiyo, et al.
(författare)
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Influence of pulsed electric field-assisted dehydration on the volatile compounds of basil leaves
- 2022
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Ingår i: Innovative Food Science and Emerging Technologies. - : Elsevier BV. - 1466-8564. ; 77
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Tidskriftsartikel (refereegranskat)abstract
- Pulsed electric field (PEF) was applied to basil leaves prior air drying at 40 °C. The parameters of the electric treatment were designed in such a way that (i) electroporated the tissue reversibly, provoking a permanent opening of the stomatal guard cells and (ii) electroporated the tissue irreversibly, damaging the cells. Treated leaves lost some volatile compounds due to both PEF treatments, probably related with the direct effect of permeabilization on the secretory cells of glandular trichomes. Upon drying, the irreversible permeabilization treatment showed the highest influence on the profile of volatiles in the dried leaves showing better retention of some terpenoids than the control. The performed statistical analysis allowed to select six compounds that can be used as markers both for the effect of pre-treatments prior dehydration and for the effects of dehydration itself on the volatile compounds of basil leaves.
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| 22. |
- Kanafusa, Sumiyo, et al.
(författare)
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The effect of nanosecond pulsed electric field on the production of metabolites from lactic acid bacteria in fermented watermelon juice
- 2021
-
Ingår i: Innovative Food Science and Emerging Technologies. - : Elsevier BV. - 1466-8564. ; 72
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Tidskriftsartikel (refereegranskat)abstract
- Lactic acid fermentation offers a processing alternative for preservation of watermelon juice, which is sensitive to heat, oxygen, and light. In this study, 8.8 × 107 CFU/mL of Lactobacillus plantarum DSM 9843 in MRS broth was inoculated in 9.9 mL of sterilized watermelon juice. Nanosecond-pulsed electric field was applied during the log growth phase of the bacteria. An 19% increase in L-lactic acid, 6.8% increase in D-lactic acid and 15% increase in acetic acid were observed over control. The final pH was 3.8. These increased levels of metabolites were dependent on the applied voltages (L-lactic acid: 5.0 kV 700 pulses, D-lactic acid: 4.5 kV 700 pulses and acetic acid: 4.5 kV 1000 pulses). The nsPEF treatment did not affect the viability of the cells and sufficient numbers remained in the product after fermentation (1.6 × 109 CFU/mL in average). These results suggest that the metabolism of lactic acid bacteria was stimulated by the PEF treatment.
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| 23. |
- Kwao, Stephen, et al.
(författare)
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Effect of guard cells electroporation on drying kinetics and aroma compounds of Genovese basil (Ocimum basilicum L.) leaves
- 2016
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Ingår i: Innovative Food Science and Emerging Technologies. - : Elsevier BV. - 1466-8564. ; 38, s. 15-23
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Tidskriftsartikel (refereegranskat)abstract
- In this study the effect of the application of pulsed electric fields as pre-treatment before air drying of basil leaves at 50 °C was investigated. The parameters of the electric treatment were designed in such a way that they either (i) electroporated the tissue reversibly (tissue remains viable) and without electroporating the guard cells in the stomata complex (65 pulses of 600 V/cm, 120 μs pulse width, 500 μs between pulses), (ii) electroporated the tissue reversibly causing the guard cells to irreversibly open the stomata (65 pulses of 600 V/cm, 150 μs pulse width, 760 μs between pulses), or (iii) irreversibly electroporated the tissue leading to cell death (65 pulses of 1500 V/cm, 150 μs pulse width, 760 μs between pulses). Results demonstrate that dehydration of basil leaves at 50 °C can be aided by the application of pulsed electric fields (PEF). If the applied PEF conditions are such that stomata are irreversibly opened while the rest of the tissue remains viable, the drying process is faster and the product keeps a better colour, is richer in aroma compounds and has better rehydration capacity than the untreated control. Irreversible tissue damage provoked by high intensity PEF drastically decreased the drying time but the measured quality characteristics of the dried leaves were inferior compared to those of the dried product when the stomatal function of the fresh leaf was selectively targeted. Industrial relevance This paper addresses the ever-increasing global demand from consumers for high-quality foods, reporting a novel methodology which improves the quality of dried aromatic herbs using pulsed electric fields.
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| 24. |
- Panarese, Valentina, et al.
(författare)
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Microscopic studies providing insight into the mechanisms of mass transfer in vacuum impregnation
- 2013
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Ingår i: Innovative Food Science & Emerging Technologies. - : Elsevier BV. - 1466-8564. ; 18, s. 169-176
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Tidskriftsartikel (refereegranskat)abstract
- A microscopic method was developed to detect pressure thresholds for gas outflow and solution impregnation during vacuum impregnation of plant materials. Raw materials with different porosities (apple and spinach) were impregnated with an isotonic sucrose solution at a minimum pressure of 150 mbar. An automatic vacuum controller system (AVCS) was used to control the pressure during vacuum impregnation. Micrographs of tissues subjected to vacuum impregnation were recorded as the pressure in the treatment chamber was varied. Image analysis allowed the evaluation of the pressure at which gas was released from the pores (seen as bubbles) during the application of vacuum, and the pressure at which tissue impregnation took place during the restoration of atmospheric pressure. Spinach tissues showed gas release at a much lower pressure than apple, and impregnation commenced at a much higher pressure. These differences in pressure threshold could be caused by the narrow pores in spinach and possibly by changes in leaf volume. Industrial relevance: Vacuum impregnation is considered a promising technology to facilitate the impregnation of vegetable tissues with different solutions containing, e.g., firming, antioxidant or antimicrobial agents. The mass transfer taking place during vacuum impregnation depends on the characteristics of the tissue pores. Effective vacuum impregnation requires the efficient removal of air from the tissue during vacuum treatment to obtain complete filling of the tissue during the subsequent impregnation step. The findings of this study may allow food manufacturers to optimize vacuum impregnation parameters depending on the porosity characteristics of the raw material. (C) 2013 Elsevier Ltd. All rights reserved.
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| 25. |
- Panarese, Valentina, et al.
(författare)
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Vacuum impregnation modulates the metabolic activity of spinach leaves
- 2014
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Ingår i: Innovative Food Science & Emerging Technologies. - : Elsevier BV. - 1466-8564. ; 26, s. 286-293
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Tidskriftsartikel (refereegranskat)abstract
- In this study calorimetric measurements provided evidence of a drastic increase of spinach leaf gross metabolism as a consequence of vacuum impregnation (VI) at a minimum pressure of 150 mbar with trehalose and sucrose isotonic solutions. When applying VI extracellular air is replaced by the impregnation solution, potentially limiting tissue respiration to any remaining air volume in the tissue. However the observation that impregnated leaves showed photosynthetic activity suggests that not all air was exhausted during VI. Hence impregnation appears to reach a maximum with remaining gas filled compartments. Metabolic inhibitors impregnated together with sugars showed that the short-term metabolic response, causing the drastic increase of gross metabolism upon VI, depends on mitochondrial oxygen consuming pathways. The metabolic effect following mannitol impregnation was comparable with water impregnation, suggesting that the strong metabolic effect reported here is only seen for molecules that can be metabolized and provide energy to the cells. Industrial relevance: Vacuum impregnation is used to incorporate additives in fruit and vegetable tissues, such as anti-browning agents, microbial preservatives or cryoprotectants. As a promising technology in the food industry, deeper insights on the metabolic consequences of vacuum impregnation are required to define and control the shelf-life of the processed fruits and vegetables. (C) 2014 Elsevier Ltd. All rights reserved.
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| 26. |
- Seratlic, Sanja, et al.
(författare)
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Behavior of the surviving population of Lactobacillus plantarum 564 upon the application of pulsed electric fields
- 2013
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Ingår i: Innovative Food Science & Emerging Technologies. - : Elsevier BV. - 1466-8564. ; 17, s. 93-98
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Tidskriftsartikel (refereegranskat)abstract
- The behavior of the surviving population of Lactobacillus plantarum 564 growing in MRS broth after pulsed electric field (PEF) treatments of different intensities was monitored by isothermal calorimetry, optical density and plate counts. Bacterial cells were treated with monopolar square pulses at varying nominal electric field strengths and number of pulses, corresponding to applied energies of 34.6, 65.8 and 658.1 J/cm(3). After the PEF treatment, samples were inoculated into the MRS broth and incubated at 37 degrees C. The presented results show that surviving bacterial cells resume growth after a treatment-dependent delay. Both the untreated and treated cultures had similar growth rates, but the latter showed a higher growth rate during the late-growth phase, and the growth rate increased with the intensity of applied electric field. After the PEF treatment, the surviving population of bacteria was less susceptible to killing by further PEF application, showing that this subpopulation was less sensitive to the PEF treatment and could grow again. Industrial relevance: The application of pulsed electric field (PEF) technology as a non-thermal alternative to traditional pasteurization of liquid foods has received considerable attention during the last years. Effective inactivation for most of the spoilage and pathogenic microorganisms has been shown in fruit and vegetable juices and milk with little or no impact on nutritional and sensorial properties of the food. However, very little is known about the growth abilities of the surviving population. Ensuring food safety requires a better understanding of the behavior of the surviving populations of microorganisms which may be recovering from sub lethal injury, such as PEF-induced stress. This paper reveals that the surviving population of the bacteria subjected to the PEF treatment could grow again, showing higher growth rates as the intensity of the PEF treatment increased. Also, the new bacterial population showed higher resistance to further PEF treatment. Therefore, for industrial application of the PEF technology, an in-depth characterization of surviving microorganisms in the treated product is required. Moreover, the evidence of bacterial persistence indicates that the PEF technology, as a non-thermal alternative to traditional pasteurization, could not completely replace thermal treatment, but can be applied as a supplement treatment. (C) 2012 Elsevier Ltd. All rights reserved.
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| 27. |
- Sorensen, Hanne, et al.
(författare)
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Dynamic ultra-high pressure homogenisation of milk casein concentrates: Influence of casein content
- 2014
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Ingår i: Innovative Food Science & Emerging Technologies. - : Elsevier BV. - 1466-8564. ; 26, s. 143-152
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Tidskriftsartikel (refereegranskat)abstract
- Milk casein concentrates with different casein-to-protein ratios (0.82 and 0.93), pH (5.8, 6.2 and 6.7) and level of applied ultra-high pressure homogenisation (UHPH) (0, 150 and 300 MPa) were studied. Samples with a casein-to-protein ratio of 0.93 at pH 5.8 and subjected to UHPH treatment at 300 MPa had the highest apparent viscosity and particle size followed by similar samples with a casein-to-protein ratio of 0.82. Water mobility was reduced at higher casein-to-protein ratio and with higher pH, while increased water mobility was observed in samples with a casein-to-protein ratio of 0.82 at pH 5.8 subjected to UHPH treatment at 300 MPa. The H-1 and P-31 NIVIR spectra revealed minor structural effects of adding casino-phospho-peptides and changing pH, but no effect of UHPH treatment, which indicate that UHPH treatment did not induce measureable structural changes in the individual proteins but rather induced changes in the tertiary structure or degree of polymerisation. Industrial relevance: Milk depleted from whey protein is advantageous to use in cheese production since it can be further processed without detrimental denaturation of whey protein which will result in reduced maturation of cheese. In combination with pH control and ultra-high pressure homogenisation of the milk casein concentrate structural changes in the protein can be obtained and new interesting milk based products can be developed. (C) 2014 Elsevier Ltd. All rights reserved.
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| 28. |
- Thamkaew, Grant, et al.
(författare)
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Influence of pulsed and moderate electric field protocols on the reversible permeabilization and drying of Thai basil leaves
- 2020
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Ingår i: Innovative Food Science and Emerging Technologies. - : Elsevier BV. - 1466-8564. ; 64
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Tidskriftsartikel (refereegranskat)abstract
- The effect of electroporation parameters on the reversible permeabilization of cells in Thai basil leaves and, specifically, cells on the leaf surface was investigated, as electroporation of stomatal guard cells decreases drying times. Various combinations of PEF and MEF parameters were applied. The effect of these parameters on the electroporation of the leaf surface was assessed with microscopic observations and the electroporation of the bulk tissues was tested with electrical resistance measurements. With PEF and MEF, the electroporation of the epidermal cells increased with increasing treatment time. Compared to epidermal cells, guard cells required larger number of pulses to achieve homogeneous electroporation. Results showed that electroporation of cells on the leaf surface increased with the increase of voltage, pulse width and number of pulses. The electroporation of cells in the bulk tissues increased with increasing voltage and pulse width. Six specific combinations of parameters were found to electroporate the guard cells on the leaf surface while maintaining the viability of the leaves.
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| 29. |
- Tylewicz, Urszula, et al.
(författare)
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Antioxidant and antimicrobial properties of organic fruits subjected to PEF assisted osmotic dehydration
- 2020
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Ingår i: Innovative Food Science and Emerging Technologies. - : Elsevier BV. - 1466-8564. ; 62, s. 1-10
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Tidskriftsartikel (refereegranskat)abstract
- The effect of PEF pre-treatment prior to osmotic dehydration on mass transfer parameters, colour, antioxidant and antimicrobial properties in organic strawberries and kiwifruits was evaluated. An increase of water loss in both fruits upon the application of combined processes was noticed (up to 21.6%), while a decrease of solid gain was observed only in kiwifruit samples dehydrated in sucrose (about 45%). In general, the combined treatments were beneficial for colour maintenance in both fruit tissues. The antioxidant capacity (DPPH) and activity (ORAC) increased after PEF treatment, however, all the combined treatments reduced significantly these values (of about 20 and 28% for strawberry and of about 56 and 35% for kiwifruit, respectively for DPPH and ORAC methods). In general, PEF treatment alone was also effective with regard to an increase in the antimicrobial activity of the samples against the tested microorganisms (B. subtilis, E.coli, S. cerevisiae)
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| 30. |
- Uhlig, E., et al.
(författare)
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Use of bacterial strains antagonistic to Escherichia coli for biocontrol of spinach : A field trial
- 2021
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Ingår i: Innovative Food Science and Emerging Technologies. - : Elsevier BV. - 1466-8564. ; 74
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Tidskriftsartikel (refereegranskat)abstract
- To counteract global food safety hazards related to raw consumption of ready-to-eat leafy vegetables, a method to improve bacterial status using antagonistic bacteria was studied under field conditions. This is the first study to identify potential Escherichia coli antagonists from the native microbiota on leafy green vegetables and evaluate their effect in an industrial field production setting. Bacterial strains were isolated from different types of leafy green vegetables and selected upon their effect against E. coli in vitro, and out of 295 tested bacterial strains, 37 showed an antagonistic effect. Four of those antagonistic strains were coated in separate treatments onto spinach seeds and planted in the field. Both seeds and plants were analyzed by Illumina MiSeq next generation sequencing (NGS), and it was seen that the microbiota of the plants contained lower relative abundance of plant and human pathogenic genera. Higher β-diversity was observed for the samples treated with Bacillus coagulans LMG P-32205 and B. coagulans LMG P-32206 compared to control, indicating that those strains have induced substantial changes in the native microbiota of the leaves. A reduction of Escherichia-Shigella was seen for two of the isolates (Pseudomonas cedrina LMG P-32207 and Pseudomonas punonenis LMG P-32204) as the seeds developed into plants. Seeds inoculated with two of the strains (B. coagulans LMG P-32205 and B. coagulans LMG P-32206) had increased levels of Lactobacillaceae, and treatment with B. coagulans LMG P-32206 resulted in lower levels of Pantoea (from 31.4 to 12.2%). These results encourage the usage of bacterial antagonists as part of a global solution to reduce the risk of human pathogens on leafy green vegetables.
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| 31. |
- Varelas, Vassileios, et al.
(författare)
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Forest biomass waste as a potential innovative source for rearing edible insects for food and feed - A review
- 2017
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Ingår i: Innovative Food Science and Emerging Technologies. - : Elsevier BV. - 1466-8564. ; 41, s. 193-205
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Forskningsöversikt (refereegranskat)abstract
- Worldwide, huge quantities of organic wastes are generated annually in the forest industry, but most of these wastes are discarded. Only a minor proportion is used, mainly for biofuel and secondarily for compost production. Simultaneously, demand for more and new food products is increasing due to rapid growth in the global population. In recent years, use of edible insects has been proposed as one promising solution to an upcoming food supply crisis. The rearing of insects for human food and livestock feed has some significant advantages, like high protein content, effective feed conversion rate, low greenhouse gas emissions and low water requirements. The aim of this review was to compile up-to-date information on rearing edible insects for food and feed and to investigate the potential use of forest biomass waste as a new substrate for insect rearing. (C) 2017 Elsevier Ltd. All rights reserved.
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| 32. |
- Wennberg, Mathias, et al.
(författare)
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On the possibility of using high pressure treatment to modify physico-chemical properties of dietary fibre in white cabbage (Brassica oleracea var. capitata)
- 2004
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Ingår i: Innovative Food Science & Emerging Technologies. - : Elsevier BV. - 1466-8564. ; 5:2, s. 171-177
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Tidskriftsartikel (refereegranskat)abstract
- The possibility of using high hydrostatic pressure (HHP) to modify the physico-chemical properties of dietary fibre polysaccharides in white cabbage (Brassica oleracea var. capitata) was studied. Two cultivars (Heckla and Predikant) were subjected to high pressure treatment (400 and 500 MPa) at different temperatures (20, 50 and 80 °C). The total dietary fibre (TDF) content was only slightly affected by HHP. However, considerable effects were generally seen in the distribution between soluble and insoluble fibre at increased pressure. When the pressure applied was 400 MPa, the proportion of soluble fibre in the cultivar Heckla was reduced at all temperatures. No additional effects were seen when the pressure was increased to 500 MPa. For the cultivar Predikant the pressure generally had to be increased to 500 MPa to attain the same effects. An exception was pressure treatment at 80 °C, where a pressure of 400 MPa was sufficient. The total dietary fibre content in unprocessed cabbage (0.1 MPa and 20 °C) was lower in the cultivar Heckla than in Predikant due to lower contents of insoluble polymers containing glucose and uronic acids. This was the case for most temperatures and pressures. It is concluded that the solubility of the dietary fibre in white cabbage can be affected by high pressure temperature treatment, which may be of importance when producing foods with specific health effects.
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| 33. |
- Xanthakis, Epameinondas, et al.
(författare)
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Development of an innovative microwave assisted food freezing process
- 2014
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Ingår i: Innovative Food Science and Emerging Technologies. - : Elsevier BV. - 1466-8564. ; 26, s. 176-181
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Tidskriftsartikel (refereegranskat)abstract
- In this study, a novel experimental setup was developed and an innovative process was implemented aiming at the application of microwave radiation during freezing of a food matrix. The results acquired from the present study are considered as remarkable and promising. The developed freezing process was applied on pork tenderloin samples. The application of microwaves during cooling the samples caused oscillated decrease of temperature and had a significant impact on the crystallization process as the degree of supercooling was decreased circa 92% under the tested conditions. The meat microstructure evaluation showed a 62% decrease in the average ice crystal size when samples were frozen under a microwave field as compared to the conventional freezing process. These results indicate that the application of microwave radiation during freezing may reduce the damage of the meat tissue and in turn to retain better texture in the frozen meat. Industrial relevance The reduction of freeze damage exerted to any tissue undergoing freezing remains a challenge. The mechanical and biochemical stress caused by the ice crystals to the cellular membranes results in irreversible tissue damage. The application of electric and/or magnetic disturbances has been identified as a possible means to reduce the size of ice crystals during freezing of biological tissues. In the present study microwaves were applied during freezing of pork meat. Our results indicate that the size of the formed ice crystals was significantly reduced during microwave assisted freezing leading to a lower damage on the microstructure of meat. This paper describes an innovative and novel freezing process that could be used in order for higher quality frozen products to be produced.
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