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Full-Text Articles in Food Processing

Cold Plasma Inactivation Of Bacterial Biofilms And Reduction Of Quorum Sensing Regulated Virulence Factors, Dana Ziuzina, Daniela Boehm, Sonal Patil, Patrick Cullen, Paula Bourke Sep 2015

Cold Plasma Inactivation Of Bacterial Biofilms And Reduction Of Quorum Sensing Regulated Virulence Factors, Dana Ziuzina, Daniela Boehm, Sonal Patil, Patrick Cullen, Paula Bourke

Articles

The main objectives of this work were to investigate the effect of atmospheric cold plasma (ACP) against a range of microbial biofilms commonly implicated in foodborne and health- care associated human infections and against P. aeruginosa quorum sensing (QS)-regu- lated virulence factors, such as pyocyanin, elastase (Las B) and biofilm formation capacity post-ACP treatment. The effect of processing factors, namely treatment time and mode of plasma exposure on antimicrobial activity of ACP were also examined. Antibiofilm activity was assessed for E. coli, L. monocytogenes and S. aureus in terms of reduction of cultur- ability and retention of metabolic activity using …


The Contribution Of Non-Thermal And Advanced Oxidation Technologies Towards Dissipation Of Pesticide Residues, N. Misra Jan 2015

The Contribution Of Non-Thermal And Advanced Oxidation Technologies Towards Dissipation Of Pesticide Residues, N. Misra

Articles

Background

The use of pesticides has stabilised the food production to a great extent and their usage cannot be avoided anymore. Nevertheless, common food processing operations always allowed dissipating pesticide residues in foods to some extent. Within the food science community and the food processing sector, non-thermal food technologies are being researched and commercialised at a great pace over the past three decades.

Scope and Approach

In this review we provide a critical analysis of the literature pertinent to the fate of pesticide residues during non-thermal processing of solid and liquid foods. We also identify the opportunities for further development …


A Soft Condensed Matter Approach Towards Mathematical Modelling Of Mass Transport And Swelling In Food Grains, Michael Chapwanya, N. Misra Aug 2014

A Soft Condensed Matter Approach Towards Mathematical Modelling Of Mass Transport And Swelling In Food Grains, Michael Chapwanya, N. Misra

Articles

Soft condensed matter (SCM) physics has recently gained importance for a large class of engineering materials. The treatment of food materials from a soft matter perspective, however, is only at the surface and is gaining importance for understanding the complex phenomena and structure of foods. In this work, we present a theoretical treatment of navy beans from a SCM perspective to describe the hydration kinetics. We solve the transport equations within a porous matrix and employ the Flory–Huggin’s equation for polymer–solvent mixture to balance the osmotic pressure. The swelling of the legume seed is modelled as a moving boundary with …


In-Package Atmospheric Pressure Cold Plasma Treatment Of Cherry Tomatoes, N. Misra, Kevin Keener, Paula Bourke, J Mosnier, Patrick Cullen Mar 2014

In-Package Atmospheric Pressure Cold Plasma Treatment Of Cherry Tomatoes, N. Misra, Kevin Keener, Paula Bourke, J Mosnier, Patrick Cullen

Articles

Cold plasma is increasingly under research for decontamination of foods, especially fresh fruits and vegetables. The effect of cold plasma on food quality, however, remains under researched. This study investigates the effects of cold plasma generated within a sealed package from a dielectric barrier discharge on the physical quality parameters and respiration rates of cherry tomatoes. Respiration rates and weight loss were monitored continuously, while other parameters are reported at the end of storage period. Differences among weight loss, pH and firmness for control and treated cherry tomatoes were insignificant towards the end of storage life. Changes in respiration rates …


In-Package Atmospheric Pressure Cold Plasma Treatment Of Strawberries, N. Misra, Paula Bourke, Patrick Cullen, Sonal Patil Mar 2014

In-Package Atmospheric Pressure Cold Plasma Treatment Of Strawberries, N. Misra, Paula Bourke, Patrick Cullen, Sonal Patil

Articles

The ability to generate low temperature plasma at atmospheric pressure offers new opportunities to decontaminate biological materials, including fresh foods. In this study, strawberries were treated with atmospheric cold plasma (ACP), generated with a 60 kV dielectric barrier discharge (DBD) pulsed at 50 Hz, across a 40 mm electrode gap, generated inside a sealed package containing ambient air (42% relative humidity). The current-voltage characteristics revealed that the plasma operated in the filamentary regime. The background microflora (aerobic mesophillic bacteria, yeast and mould) of strawberries treated for 5 min was reduced by 2 log 10 within 24 h of post-ACP treatment. …


In-Package Nonthermal Plasma Degradation Of Pesticides On Fresh Produce, N. Misra, Shashi Pankaj, Tony Walsh, Finbarr O'Regan, Paula Bourke, Patrick Cullen Feb 2014

In-Package Nonthermal Plasma Degradation Of Pesticides On Fresh Produce, N. Misra, Shashi Pankaj, Tony Walsh, Finbarr O'Regan, Paula Bourke, Patrick Cullen

Articles

In-package nonthermal plasma (NTP) technology is a novel technology for the decontamination of foods and biological materials. This study presents the first report on the potential of the technology for the degradation of pesticide residues. A cocktail of pesticides, namely Azoxystrobin, Cyprodinil, Fludioxonil and Pyriproxyfen was tested on strawberries. The concentrations of these pesticides were monitored in priori and post- plasma treatment using GC-MS/MS. An applied voltage and time dependent degradation of the pesticides was observed for treatment voltages of 60, 70 and 80 kV and treatment durations ranging from 1 to 5 min, followed by 24 h in-pack storage. …


Atmospheric Cold Plasma Inactivation Of Escherichia Coli, Salmonella Enterica Serovar Typhimurium And Listeria Monocytogenes Inoculated On Fresh Produce, Dana Ziuzina, Sonal Patil, Patrick Cullen, Kevin Keener, Paula Bourke Jan 2014

Atmospheric Cold Plasma Inactivation Of Escherichia Coli, Salmonella Enterica Serovar Typhimurium And Listeria Monocytogenes Inoculated On Fresh Produce, Dana Ziuzina, Sonal Patil, Patrick Cullen, Kevin Keener, Paula Bourke

Articles

Atmospheric cold plasma (ACP) represents a potential alternative to traditional methods for non-thermal decontamination of foods. In this study, the antimicrobial efficacy of a novel dielectric barrier discharge ACP device against Escherichia coli, Salmonella enterica Typhimurium and Listeria monocytogenes inoculated on cherry tomatoes and strawberries, was examined. Bacteria were spot inoculated on the produce surface, air dried and sealed inside a rigid polypropylene container. Samples were indirectly exposed (i.e. placed outside plasma discharge) to a high voltage (70kVRMS) air ACP and subsequently stored at room temperature for 24 h. ACP treatment for 10, 60 and 120 s resulted in reduction …


Ultrasound Assisted Hydration Of Navy Beans (Phaseolus Vulgaris), N. Misra Jan 2014

Ultrasound Assisted Hydration Of Navy Beans (Phaseolus Vulgaris), N. Misra

Articles

The use of ultrasound to enhance the transport phenomena in food processes has been well recognised in recent times. The objective of this study was to evaluate the effect of sonication on hydration rate and pasting profile of navy beans. The hydration kinetics for control and ultrasound assisted soaking was mathematically described using mechanistic (Fickian diffusion) and empirical (Peleg’s equation, Weibull model and First Order equation) models. Ultrasound enhanced the rate of hydration which was evident from the plot of kinetic data and model parameters. The effective diffusivities for water transport without and with ultrasound application were estimated to be …


Kinetic Studies For The Preparation Of Probiotic Cabbage Juice: Impact On Phytochemicals And Bioactivity, Amit Jaiswal, Nissreen Abu-Ghannam Aug 2013

Kinetic Studies For The Preparation Of Probiotic Cabbage Juice: Impact On Phytochemicals And Bioactivity, Amit Jaiswal, Nissreen Abu-Ghannam

Articles

A kinetic study for the production of probiotic cabbage juice was carried out under controlled pH and dissolved oxygen using several strains of Lactic acid bacteria (LAB). Furthermore, effect of probiotic fermentation on polyphenolic content and antioxidant capacity was investigated. Results showed significant growth in Lactobacillus brevis, Lactobacillus plantarum and Lactobacillus rhamnosus corresponding to 9.19, 9.47 and 10.6 log CFU/ml after 24 h of fermentation, which is satisfying criteria for a food product to be characterized as probiotic. Lactic acid (LA) was the major end product of the fermented cabbage juice attaining the concentrations of 6.97, 9.69 and 12.2 g/l …


Enhancement Of The Phytochemical And Fibre Content Of Beef-Patties With Himanthalia Elongata Seaweed, Sabrina Cox, Nissreen Abu-Ghannam Jun 2013

Enhancement Of The Phytochemical And Fibre Content Of Beef-Patties With Himanthalia Elongata Seaweed, Sabrina Cox, Nissreen Abu-Ghannam

Articles

The effect of adding Himanthalia elongata seaweed (10 - 40% w/w) as a source of antioxidants and dietary fibre on physical, chemical, microbial and sensory traits of cooked beef patties was studied throughout chilled storage. Patties with seaweed showed reduced cooking losses and were nearly 50% more tender as compared to patties without seaweed. Microbiological counts and lipid oxidation were significantly lower in patties containing seaweed (P < 0.05), by day 30 of storage there was no bacterial growth in samples with ≥ 20% seaweed and lipid oxidation levels were low (0.61 mg malondialdehyde/kg of sample). Seaweed incorporation significantly increased the dietary fibre (1.64 g per 100 g fw in 40% seaweed-patties), total phenolic content (up to 28.11 mg GAE/100 g fw) and DPPH radical scavenging activity (up to 52.32%) of patties compared to the control. Sensory analysis indicated that the seaweed-patties were accepted by consumers in terms of aroma, appearance, texture and taste. Patties containing 40% seaweed were rated highest in terms of overall acceptability, most likely due to improvement in texture and mouthfeel. Addition of seaweed in the formulation of beef patties leads to the enhancement of the nutritional and technological quality together with an acceptable sensory quality.


Incorporation Of Himanthalia Elongata Seaweed To Enhance The Phytochemical Content Of Breadsticks Using Response Surface Methodology (Rsm), Sabrina Cox, Nissreen Abu-Ghannam Jun 2013

Incorporation Of Himanthalia Elongata Seaweed To Enhance The Phytochemical Content Of Breadsticks Using Response Surface Methodology (Rsm), Sabrina Cox, Nissreen Abu-Ghannam

Articles

Optimization of incorporating seaweed into breadsticks was carried out using response surface methodology (RSM). Ten formulations of breadsticks were processed by varying concentrations of seaweed (X1 = 5 to 15% of overall flour concentration) and white flour (X2 = 10 to 30% of overall flour concentration) using a central composite design. The remaining flour concentrations were comprised of wholemeal flour. Predicted models were found to be significant (P < 0.05) for total phenolic content (TPC), DPPH radical scavenging activity, texture and color. Predicted values for each of the responses were in good agreement with the experimental values. Seaweed concentration had most significant effect on phytochemical constituents of the breadsticks with TPC and DPPH activity maximized when 17.07% H. elongata was incorporated into the flour (P < 0.05). An acceptable edible texture and color of breadsticks was also achieved at this concentration. Multiple response optimization demonstrated that phytochemical content of H. elongata breadsticks may be maximized with dried seaweed and white flour concentrations of 17.07 and 21.89%, respectively, in the …


The Effect Of Non-Thermal Processing Technologies On Microbial Inactivation: An Investigation Into Sub-Lethal Injury Of Escherichia Coli And Pseudomonas Fluorescens, Rachel Halpin, L. Duffy, O. Cregenzán-Alberti,, J.G Lyng, F. Noci Jan 2013

The Effect Of Non-Thermal Processing Technologies On Microbial Inactivation: An Investigation Into Sub-Lethal Injury Of Escherichia Coli And Pseudomonas Fluorescens, Rachel Halpin, L. Duffy, O. Cregenzán-Alberti,, J.G Lyng, F. Noci

Articles

In recent years, there has been an increased interest in food processing technologies that could lessen the thermal impact on food products. In the present study, thermosonication (TS) and pulsed electric fields (PEF), applied individually or in combination (TS/PEF), were investigated to determine their effects on inactivation and sub-lethal injury of Pseudomonas fluorescens and Escherichia coli. TS was applied at a low (L) and high (H) wave amplitude (18.6 μm and 27.9 μm, respectively), while PEF was applied at a low and high electrical field strength (29 kV cm−1 and 32 kV cm−1, respectively). In addition, …


Optimization Of Fermentation Conditions For The Utilization Of Brewing Waste To Develop A Nutraceutical Rich Liquid Product, Shilpi Gupta, Amit Jaiswal, Nissreen Abu-Ghannam Jan 2013

Optimization Of Fermentation Conditions For The Utilization Of Brewing Waste To Develop A Nutraceutical Rich Liquid Product, Shilpi Gupta, Amit Jaiswal, Nissreen Abu-Ghannam

Articles

Utilization of brewers’ spent grain (BSG), for the development of a fermented liquid product rich in value-added phenolic compounds was investigated. Changes in and liberation of phenolic compounds and antioxidant activity during fermentation of BSG was studied. The effect of various particle size (PS), solid liquid (SL) ratio, fermentation time and rotation speed was optimized using response surface methodology (RSM) for the purpose of improving bacterial growth and the enhancement in the release of polyphenolic compounds. Contour maps generated using the response surface equation showed that the experimental variables significantly affected the response. A production of 10.4 log cfu/ml, 2.95 …


Antioxidant Capacity, Arabinoxylans Content And In Vitro Glycaemic Index Of Cereal-Based Snacks Incorporated With Brewer’S Spent Grain, Sofia Reis, Nissreen Abu-Ghannam Jan 2013

Antioxidant Capacity, Arabinoxylans Content And In Vitro Glycaemic Index Of Cereal-Based Snacks Incorporated With Brewer’S Spent Grain, Sofia Reis, Nissreen Abu-Ghannam

Articles

Extruded snacks and breadsticks were formulated with increasing levels of brewer’s spent grain (BSG). The phenolic content increased by 4 and 7 fold with BSG addition in extrudates (40g/100g) and in breadsticks (35g/100g), respectively. Consequently, antioxidant capacity (DPPH, FRAP) also increased despite a recorded loss of phenolic compounds in extruded snacks. Arabinoxylans content increased up to 20 and 25g of BSG addition /100g of formulated extruded snacks and breadsticks, respectively. Further addition of BSG did not improve the content of arabinoxylans due to the possible formation of polysaccharide-protein complexes. Medium GI breadsticks were obtained with 35g of BSG incorporation /100g …


Degradation Kinetic Modelling Of Colour, Texture, Polyphenols And Antioxidant Capacity Of York Cabbage After Microwave Processing, Amit Jaiswal, Nissreen Abu-Ghannam Jan 2013

Degradation Kinetic Modelling Of Colour, Texture, Polyphenols And Antioxidant Capacity Of York Cabbage After Microwave Processing, Amit Jaiswal, Nissreen Abu-Ghannam

Articles

Vegetables as an essential component of the human diet usually undergo some type of processing before being consumed. In the present study, impact of microwave (MW) processing on various physiochemical properties of York cabbage was studied. York cabbage was processed at 400, 560 and 800W for 0 to 14 min with an increment of 2 min followed by a kinetic study for the degradation of polyphenols, flavonoids, antioxidant capacity, colour and texture were carried out. Results showed that MW processing leads to significant reductions in the texture, colour, polyphenols and antioxidant capacity. For all the MW processing power studied total …


Optimization Of Lactic Acid Fermentation Of York Cabbage For The Development Of Potential Probiotic Products, Amit Jaiswal, Shilpi Gupta, Nissreen Abu-Ghannam Jan 2012

Optimization Of Lactic Acid Fermentation Of York Cabbage For The Development Of Potential Probiotic Products, Amit Jaiswal, Shilpi Gupta, Nissreen Abu-Ghannam

Articles

In the present study, York cabbage was used as the sole substrate for the lactic acid (LA) fermentation with Lactobacillus plantarum. York cabbage was blanched at 95°C for 12min to inactivate surface microflora prior to fermentation. To achieve an optimal fermentation condition which would result in higher release of phytochemicals and antioxidant (AO) capacity in the broth, Box-Behnken design integrating a desirability approach was used. A second-order polynomial equation was developed indicating the effect of solute/liquid ratio, agitation rate and fermentation time on desired parameters. The optimized factors were used for fermenting York cabbage to obtain maximum bacterial growth, …


Effect Of Different Rehydration Temperatures On The Moisture And Phytochemical Constituents Of Dried Edible Irish Brown Seaweed., Sabrina Cox, Shilpi Gupta, Nissreen Abu-Ghannam Jan 2012

Effect Of Different Rehydration Temperatures On The Moisture And Phytochemical Constituents Of Dried Edible Irish Brown Seaweed., Sabrina Cox, Shilpi Gupta, Nissreen Abu-Ghannam

Articles

The effect of temperature (20, 40, 60, 80 and 100 °C) on the rehydration kinetics and phytochemical constituents of dried edible Irish brown seaweed, Himanthalia elongata, were studied. The moisture content of fresh and dried seaweed was 4.07 and 0.07 g water/g dry basis, representing a 98.1% reduction in water content. All rehydration moisture curves had a clear exponential tendency, and it was observed that the rehydration time decreased when temperature was increased. Although restoration of the product to its original moisture content was achieved, rehydration resulted in losses in phytochemical content. Moisture equilibrium was achieved fastest at 100 °C …


Brewer’S Spent Grain As A Functional Ingredient For Breadsticks, Anastasia Ktenioudaki, Valérie Chaurin, Sofia Reis, Eimear Gallagher Jan 2012

Brewer’S Spent Grain As A Functional Ingredient For Breadsticks, Anastasia Ktenioudaki, Valérie Chaurin, Sofia Reis, Eimear Gallagher

Articles

Brewer’s spent grain (BSG) was evaluated for its potential as a functional baking ingredient. Scanning electron microscopy (SEM) was used to examine the microstructure of BSG and wheat flours. Baked snacks (breadsticks) were prepared using 15%, 25% and 35% BSG and evaluated for their baking quality and fibre and protein content (over a period of 3 months). The addition of BSG altered the baking characteristics of the breadsticks by affecting their structure and texture. The snacks appeared to lack in cellular structure and crispiness. However, they had quite a stable shelf-life, as changes in texture, moisture and aw progressed at …


Statistical Optimization Of Blanching Time And Temperature Of Irish York Cabbage Using Desirability Function, Amit Jaiswal, Nissreen Abu-Ghannam, Shilpi Gupta Dec 2011

Statistical Optimization Of Blanching Time And Temperature Of Irish York Cabbage Using Desirability Function, Amit Jaiswal, Nissreen Abu-Ghannam, Shilpi Gupta

Articles

The effect of different heat treatments, as a means of preprocessing, on the phytochemicals present in Irish York cabbage was studied. A comparison of blanching (by immersing in water) and microwaving (using water as a medium) indicated that microwaving is detrimental to the phytochemicals present in cabbage. To achieve a blanching time and temperature combination that would result in minimal loss of phytochemicals, central composite design that integrates a desirability approach was used. A second-order polynomial equation was developed, indicating the effect of the blanching time and temperature on the total phenol content (TPC), total flavonoid content (TFC) and 2,2-diphenyl-1-picrylhydrazyl …


Nonthermal Plasma Inactivation Of Food-Borne Pathogens, N. Misra, B. Tiwari, K. Rahavarao, Patrick Cullen Oct 2011

Nonthermal Plasma Inactivation Of Food-Borne Pathogens, N. Misra, B. Tiwari, K. Rahavarao, Patrick Cullen

Articles

Non-thermal plasma (NTP) is electrically energized matter, composed of highly reactive species including gas molecules, charged particles in the form of positive ions, negative ions, free radicals, electrons and quanta of electromagnetic radiation (photons) at near-room temperature. NTP is an emerging nonthermal technology with potential applications for decontamination in the food industries. An upsurge in the research activities for plasma based inactivation of food borne pathogens is evident in the recent years. These studies have shown that NTP can be used for the surface decontamination of raw produce, dried nuts and the packaging materials etc. This paper reviews the action …


Effect Of Processing Conditions On Phytochemical Constituents Of Edible Irish Seaweed Himanthalia Elongata., Sabrina Cox, Nissreen Abu-Ghannam, Shilpi Gupta Jan 2011

Effect Of Processing Conditions On Phytochemical Constituents Of Edible Irish Seaweed Himanthalia Elongata., Sabrina Cox, Nissreen Abu-Ghannam, Shilpi Gupta

Articles

Seaweed iswell recognized as an excellent source of phytochemicals. This study was a preliminary screening to investigate the effects of various food processing methods on the phytochemicals of Himanthalia elongata. Hydrothermal processing was carried out until an edible texture was achieved. The total phenolic content (TPC) of fresh H. elongata was 175.27 mg gallic acid equivalent (GAE)/100 g fresh weight (FW) while boiling significantly reduced the TPC to 25.4 mg GAE/100 g FW
(P < 0.05).A drying pretreatment before boiling reduced the cooking time therefore leading to less leaching of antioxidants upon boiling. In terms of extract, drying of H. elongata followed by boiling had the most significant effect on the phytochemicals as TPC increased by 174%. Boiled extracts had the most effective 2, 2-diphenyl- 1-picrylhydrazyl scavenging activity (EC50 of 12.5 mg/mL). As a comparison, seaweed subjected to the same treatments was studied in terms of antimicrobial activity.Overall, extracts fromfresh H. elongata achieved the highest inhibition.


Application Of Response Surface Methodology For Studying The Influence Of Hydrothermal Processing On The Phytochemical Constituents Of Irish Edible Brown Seaweed, Sabrina Cox Jan 2011

Application Of Response Surface Methodology For Studying The Influence Of Hydrothermal Processing On The Phytochemical Constituents Of Irish Edible Brown Seaweed, Sabrina Cox

Articles

We used response surface methodology to investigate the effect of time and temperature of hydrothermal processing (blanching) on the phytochemical content, texture and colour of a semi-dried brown seaweed ( Himanthalia elongata ). A central composite design was employed with a hydrothermal processing time of 10 – 30 min and temperature of 60 – 90 ° C. Predicted models were found to be signifi cant for total phenolic content, 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity, total fl avonoids, total condensed tannins, texture and colour. The predicted values for each of the responses were in good agreement with experimental values. Processing time had …


Effect Of Different Drying Temperatures On The Moisture And Phytochemical Constituents Of Edible Irish Brown Seaweed, Shilpi Gupta, Sabrina Cox, Nissreen Abu-Ghannam Jan 2011

Effect Of Different Drying Temperatures On The Moisture And Phytochemical Constituents Of Edible Irish Brown Seaweed, Shilpi Gupta, Sabrina Cox, Nissreen Abu-Ghannam

Articles

The effect of different temperatures on the drying kinetics and the phytochemical constituents of edible Irish brown seaweed, Himanthalia elongata were studied. This kinetic study involved the modelling of the terms of Fick’s diffusion equation, for estimation of the diffusion coefficients. The diffusivity coefficient increased from 5.6×10−07-12.2×10−07 m2/s as the drying temperatures increased with an estimated activation energy of 37.2 kJ/mol. The experimental data was also fitted to different empirical kinetic models, Newton, Logarithmic and Henderson-Pabis, and the goodness of fit for the different models was evaluated. The effect of drying temperatures on the phytochemical constituents in seaweed was also …


The Effect Of Untreated And Enzyme-Treated Commercial Dairy Powders On The Growth And Adhesion Of Streptococcus Mutans, Rachel Halpin, D.B. Brady, E.D. O’Riordan, M. O’Sullivan Jan 2011

The Effect Of Untreated And Enzyme-Treated Commercial Dairy Powders On The Growth And Adhesion Of Streptococcus Mutans, Rachel Halpin, D.B. Brady, E.D. O’Riordan, M. O’Sullivan

Articles

Dental caries is a common bacterial infection, but the progression of this disease can be delayed by preventing initial attachment of cariogenic bacteria such as Streptococcus mutans to tooth surfaces. This study firstly compares the effect of untreated (UT) and enzyme-treated (ET) dairy powders on the adherence of S. mutans to hydroxylapatite (HA), an analogue of tooth enamel. A fluorescence-based method was used to quantify adherence of S. mutans to HA both in the presence (S-HA) and absence (PBS-HA) of saliva. Secondly, binding of proteins present in the test materials to HA was quantified using bicinchonic acid assays and SDS-PAGE. …


Application Of Response Surface Methodology For Studying The Influence Of Hydrothermal Processing On The Phytochemical Constituents Of Irish Edible Brown Seaweed, Sabrina Cox, Shilpi Gupta, Nissreen Abu-Ghannam Jan 2011

Application Of Response Surface Methodology For Studying The Influence Of Hydrothermal Processing On The Phytochemical Constituents Of Irish Edible Brown Seaweed, Sabrina Cox, Shilpi Gupta, Nissreen Abu-Ghannam

Articles

We used response surface methodology to investigate the effect of time and temperature of hydrothermal processing (blanching) on the phytochemical content, texture and colour
of a semi-dried brown seaweed ( Himanthalia elongata ). A central composite design was employed with a hydrothermal processing time of 10 – 30 min and temperature of 60 – 90 ° C. Predicted models were found to be signifi cant for total phenolic
content, 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity, total fl avonoids, total condensed tannins, texture and colour. The predicted values for each of the responses were in good agreement with experimental values. Processing time had …


Determination Of The Effect Of Dairy Powders On Adherence Of Streptococcus Sobrinus And Streptococcus Salivarius To Hydroxylapatite And Growth Of These Bacteria, Rachel Halpin, D.B. Brady, E.D. O’Riordan, M. O’Sullivan Dec 2010

Determination Of The Effect Of Dairy Powders On Adherence Of Streptococcus Sobrinus And Streptococcus Salivarius To Hydroxylapatite And Growth Of These Bacteria, Rachel Halpin, D.B. Brady, E.D. O’Riordan, M. O’Sullivan

Articles

Dental caries is a highly prevalent disease caused by colonisation of tooth surfaces by cariogenic bacteria, such as Streptococcus sobrinus and Streptococcus salivarius. Reducing initial adherence of such bacteria to teeth may delay onset of caries. Many foods, such as milk, can inhibit microbial adherence. In this investigation, the effect of untreated (UT) and enzyme-treated (ET) dairy powders on adherence of S. sobrinus and S. salivarius to hydroxylapatite (HA), an analogue of tooth enamel, was examined. Untreated (UT) acid whey protein concentrate (AWPC) 80 inhibited streptococcal adherence to phosphate-buffered saline-coated HA (PBS-HA) and saliva-coated HA (S-HA) by >80% at …


Barley For Brewing: Characteristic Changes During Malting, Brewing And Applications Of Its By-Products, Mahesh Gupta, Nissreen Abu-Ghannam, Eimear Gallaghar Aug 2010

Barley For Brewing: Characteristic Changes During Malting, Brewing And Applications Of Its By-Products, Mahesh Gupta, Nissreen Abu-Ghannam, Eimear Gallaghar

Articles

Barley is the basic raw material for brewing. Its chemical composition, brewing, and technological indices are highly determinative for the beer quality and the economical efficiency of the brewing process. Barley is rich in protein, carbohydrates, dietary fibers, minerals, and vitamins. The presence of non starch polysaccharides as mixed linkage (1-3),(1-4)-β-D-glucans and arabinoxylans together with the enzymes are responsible for barley modification. Malting is a complex process that involves many enzymes; important ones are α-amylase, β-amylase, α-glucosidase, and limit dextrinase. During the process of malting and brewing, the by-products left after separation of the wort are rich in protein, fibers, …


Effect Of Hydrothermal Processing On Colour, Antioxidant And Free Radical Scavenging Capacities Of Edible Irish Brown Seaweeds, Gaurav Rajauria, Amit Jaiswal, Nissreen Abu-Ghannam, Shilpi Gupta Jul 2010

Effect Of Hydrothermal Processing On Colour, Antioxidant And Free Radical Scavenging Capacities Of Edible Irish Brown Seaweeds, Gaurav Rajauria, Amit Jaiswal, Nissreen Abu-Ghannam, Shilpi Gupta

Articles

The effect of heat processing on change in colour (ΔE), level of bioactive compounds and overall antioxidant capacity in raw and heat processed Irish brown seaweeds was investigated. Raw seaweeds were heated at 85, 95, 100, 110 and 121 °C for 15 min in an autoclave and the samples were extracted with 60% methanol. Total phenol (TPC), total tannin (TTC), DPPH• scavenging and metal chelating ability (FIC) were significantly higher (p < 0.05) at 85 °C while the value of ΔE, total flavonoid (TFC), total sugar (TSC), lipid peroxidation and H2O2 scavenging capacity were higher at 95 °C, as compared to raw seaweeds, in all the species studied. Results showed that heat treatment affects not only the content of bioactive compounds in seaweeds but also beneficial biological activity associated with these compounds which can suggest new processing for the application of seaweeds extract as nutraceutical.


An Assessment Of The Antioxidant And Antimicrobial Activity Of Six Species Of Edible Irish Seaweeds, Sabrina Cox, Nissreen Abu-Ghannam, Shilpi Gupta Apr 2010

An Assessment Of The Antioxidant And Antimicrobial Activity Of Six Species Of Edible Irish Seaweeds, Sabrina Cox, Nissreen Abu-Ghannam, Shilpi Gupta

Articles

Six species of edible Irish seaweeds; Laminaria digitata, Laminaria saccharina, Himanthalia elongata, Palmaria palmata, Chondrus crispus and Enteromorpha spirulina were screened for potential bioactivity. Extraction of secondary metabolites was carried out using different solvents to determine antioxidant and antimicrobial properties of the dried extracts. The total phenolic contents of dried methanolic extracts were significantly different (p < 0.05). H. elongata exhibited highest phenolic content at 151.3 mg GAE/g of seaweed extract and also had the highest DPPH scavenging activity (p < 0.05) with a 50% inhibition (EC50) level at 0.125μg/ml of extract. H. elongata also had the highest total tannin and total flavonoid contents (p < 0.05) of 38.34 mg CE/g and 42.5 mg QE/g, respectively. Antimicrobial activity was determined using a microtitre method which allowed detection of bacterial growth inhibition at low levels. All methanolic seaweed extracts inhibited the food spoilage and food pathogenic bacteria tested; Listeria monocytogenes, Salmonella abony, Enterococcus faecalis and Pseudomonas aeruginosa, except C. crispus extracts. It was found that dried methanolic extracts of red and green seaweeds had significantly lower antimicrobial activity than the brown species; H. elongata had the highest antimicrobial activity with up to 100% inhibition. In the studied work, the antimicrobial activity of red and green seaweed extracts significantly increased when ethanol and acetone were used as extraction solvents (p < 0.05). Inhibition of E. faecalis with C. crispus extracts increased from 39.28 to 100% when ethanol and acetone were applied as solvents.


Antioxidant Capacity And Polyphenol Content Of Brown Seaweeds After Heat Processing, Gaurav Rajauria, Shilpi Gupta, Nissreen Abu-Ghannam, Amit Jaiswal Mar 2010

Antioxidant Capacity And Polyphenol Content Of Brown Seaweeds After Heat Processing, Gaurav Rajauria, Shilpi Gupta, Nissreen Abu-Ghannam, Amit Jaiswal

Articles

Seaweeds or marine macroalgae are renewable living resources which are also used as food, feed and fertilizer in many parts of the world. They are able to produce a great variety of secondary metabolites characterized by a broad spectrum of biological behavior such as antibacterial and antioxidant activities. The effect of heat treatment was investigated on the level of bioactive compounds and changes in the overall antioxidant capacity of edible Irish brown seaweeds namely Himanthalia elongata, Laminaria saccharina and Laminaria digitata. In order to make the seaweeds safe and edible, they were heated at 85, 95, 100, 110 and 121°C …