Open Access. Powered by Scholars. Published by Universities.®

Food Processing Commons

Open Access. Powered by Scholars. Published by Universities.®

Technological University Dublin

Discipline
Keyword
Publication Year
Publication

Articles 61 - 85 of 85

Full-Text Articles in Food Processing

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

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


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 …


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 …


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 …


Metabolic Profiling And Fingerprinting For The Detection And Discrimination Of Mechanical Damage In Mushrooms (Agaricus Bisporus) During Storage, Aoife O'Gorman Oct 2010

Metabolic Profiling And Fingerprinting For The Detection And Discrimination Of Mechanical Damage In Mushrooms (Agaricus Bisporus) During Storage, Aoife O'Gorman

Doctoral

Horticultural products such as mushrooms are exposed to external agents during their postharvest life, which are going to affect product quality. Loss of whiteness during storage is particularly important in the mushroom industry. Rough handling and distribution of crops, fruiting body senescence, bacterial and viral infection are among the causes of mushroom discolouration. The aim of this work was to study the use of metabolic fingerprinting and metabolic profiling tools for the detection and discrimination of mechanical damage on mushrooms. This research involved: 1. Investigating whether the chemical changes induced by mechanical damage and ageing of mushrooms could be (a) …


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 …


Effect Of Ultrasonic Processing On Food Enzymes Of Industrial Importance, Paula Bourke, Brijesh Tiwari, Colm O Donnell, Patrick J. Cullen Jan 2010

Effect Of Ultrasonic Processing On Food Enzymes Of Industrial Importance, Paula Bourke, Brijesh Tiwari, Colm O Donnell, Patrick J. Cullen

Articles

In the last decade power ultrasound has emerged as an alternative processing option to conventional thermal approaches for pasteurisation and sterilisation of food products. While sonication alone is not adequate for inactivation of various spoilage and harmful enzymes present in food, ultrasound in combination with mild heat treatment and/or pressure has shown potential for both enzyme and pathogen inactivation. Numerous studies have investigated ultrasound for inactivating enzymes such as pectinmethylesterase, polyphenoloxidases and peroxidases responsible for deterioration of fruit & vegetable juice and various enzymes pertinent to milk quality. The efficacy of ultrasound for the inactivation of enzymes in food is …


Quality And Safety Assessment During The Ozonation Of Cloudy Apple Juice, Sonal Patil, B. Torres, Brijesh Tiwari, Hilda Wingaard, Paula Bourke, Patrick J. Cullen, C. O'Donnell, Vasilis Valdramidis Jan 2010

Quality And Safety Assessment During The Ozonation Of Cloudy Apple Juice, Sonal Patil, B. Torres, Brijesh Tiwari, Hilda Wingaard, Paula Bourke, Patrick J. Cullen, C. O'Donnell, Vasilis Valdramidis

Articles

Traditionally, ozone processing within the food industry has focused on solid foods by either gaseous treatment or washing with ozonated water. However, with the FDA’s approval of ozone as a direct additive to food, the potential for liquid applications has emerged. This study investigates the effect of ozone processing on microbial inactivation (E. coli ATCC 25922 and NCTC 12900), and quality parameters (colour, phenolic content) of apple juice. Apple juice samples were ozonated at room temperature (20±1.5oC) with an ozone concentration of 0.048 mg O3 min-1 ml-1 and treatment time of 0 to 10 …


Growth And Kinetics Of Lactobacillus Plantarum In The Fermentation Of Edible Irish Brown Seaweeds, Shilpi Gupta, Nissreen Abu-Ghannam, Amalia G.M. Scannell Jan 2010

Growth And Kinetics Of Lactobacillus Plantarum In The Fermentation Of Edible Irish Brown Seaweeds, Shilpi Gupta, Nissreen Abu-Ghannam, Amalia G.M. Scannell

Articles

The aim of the present study was to see the applicability of using brown edible seaweeds as a sole source of nutrition for the growth of lactic acid bacteria. Growth kinetics of lactic acid bacteria (LAB; Lactobacillus plantarum) was studied using three species of edible Irish brown seaweeds Himanthalia elongata, Laminaria digitata and Laminaria saccharina. As part of the screening process, growth of the LAB was carried out on raw and heat treated forms of seaweeds. The seaweed species in their raw state could not support the growth of L. plantarum. Heat treatment resulted in almost 4 times increase in …


Inactivation Of Escherichia Coli By Ozone Treatment Of Apple Juice At Different Ph Levels, Sonal Patil, Vasilis Valdramidis, Patrick J. Cullen, Jesus Maria Frias, Paula Bourke Jan 2010

Inactivation Of Escherichia Coli By Ozone Treatment Of Apple Juice At Different Ph Levels, Sonal Patil, Vasilis Valdramidis, Patrick J. Cullen, Jesus Maria Frias, Paula Bourke

Articles

This research investigated the efficacy of gaseous ozone for the inactivation of Escherichia coli ATCC 25922 and NCTC 12900 strains in orange juice. Orange juice inoculated with E. coli (106 CFU mL-1) as a challenge microorganism was treated with ozone at 75-78µg mL-1 for different time periods (0-18 min). The efficacy of ozone for inactivation of both strains of E. coli was evaluated as a function of different juice types: model orange juice, fresh unfiltered juice, juice without pulp, and juice filtered through 500mm or 1mm sieves. Fast inactivation rates for total reduction of E. coli …


Ozone Inactivation Of Acid Stressed Listeria Monocytogenes And Listeria Innocua In Orange Juice Using A Bubble Column, Sonal Patil, Vasilis Valdramidis, Jesus Maria Frias, Patrick J. Cullen, Paula Bourke Jan 2010

Ozone Inactivation Of Acid Stressed Listeria Monocytogenes And Listeria Innocua In Orange Juice Using A Bubble Column, Sonal Patil, Vasilis Valdramidis, Jesus Maria Frias, Patrick J. Cullen, Paula Bourke

Articles

Orange juice inoculated with Listeria monocytogenes strains ATCC 7644, NCTC 11994 and Listeria innocua NCTC 11288 (106 CFU/ml) as challenge microorganisms was treated with direct ozone at 0.098mg/min/ml for different time periods (0-8 min) using an ozone bubble column. Ozone treatment of mild acid stressed and mild acid stress-habituated (pH 5.5) cells of L. monocytogenes resulted in higher inactivation times compared to control non-acid stressed cells. Additionally acid stressed cells habituated in orange juice (ATCC 7644 & NCTC 11288), showed higher inactivation times during ozonation by comparison with the control as well as the mild-acid stressed cells. Overall the …


Prediction Of Polyphenol Oxidase Activity Using Visible Near-Infrared Hyperspectral Imaging On Mushroom (Agaricus Bisporus) Caps., Edurne Gaston, Jesus Maria Frias, Patrick J. Cullen, Colm O'Donnell, Aoife Gowen Jan 2010

Prediction Of Polyphenol Oxidase Activity Using Visible Near-Infrared Hyperspectral Imaging On Mushroom (Agaricus Bisporus) Caps., Edurne Gaston, Jesus Maria Frias, Patrick J. Cullen, Colm O'Donnell, Aoife Gowen

Articles

Physical stress (i.e. bruising) during harvesting, handling and transportation triggers enzymatic discoloration of mushrooms, a common and detrimental phenomenon largely mediated by polyphenol oxidase (PPO) enzymes. Hyperspectral imaging (HSI) is a non-destructive technique that combines imaging and spectroscopy to obtain information from a sample. The objective of this study was to assess the ability of HSI to predict the activity of PPO on mushroom caps. Hyperspectral images of mushrooms subjected to various damage treatments were taken, followed by enzyme extraction and PPO activity measurement. Principal component regression (PCR) models (each with 3 PCs) built on raw reflectance and multiple scatter …


Postharvest Hardness And Color Evolution Of White Button Mushrooms (Agaricus Bisporus)., Debabandya Mohapatra, Zuberi M. Bira, Joseph Kerry, Jesus Maria Frias, Fernanda A.R. Oliveira Jan 2010

Postharvest Hardness And Color Evolution Of White Button Mushrooms (Agaricus Bisporus)., Debabandya Mohapatra, Zuberi M. Bira, Joseph Kerry, Jesus Maria Frias, Fernanda A.R. Oliveira

Articles

The quality evaluation of mushrooms was studied by storing fresh white button mushroom (Agaricus bisporus) for 6-8 days, at various controlled temperature conditions (3.5 -15°C) and measuring the instrumental textural hardness and color of the mushroom cap for different product batches. A non linear mixed effect weibull model was used to describe mushroom cap texture and color kinetics during storage considering the batch variability into account. Storage temperature was found to play a significant role in controlling texture and colour degradation. On lowering storage temperature i) the extent of the final browning extent in the mushroom after storage …


Study Of The Microbial Diversity And Antimicrobial Properties Of Irish Edible Brown Seaweeds, Shilpi Gupta, Gaurav Rajauria, Nissreen Abu-Ghannam Jan 2010

Study Of The Microbial Diversity And Antimicrobial Properties Of Irish Edible Brown Seaweeds, Shilpi Gupta, Gaurav Rajauria, Nissreen Abu-Ghannam

Articles

Brown Irish edible seaweeds, Himanthalia elongata, Laminaria sachharina and Laminaria digitata, were evaluated for the microbiota in raw and heat processed form. Raw seaweeds showed complete absence of aerobic mesophiles, halophiles, yeasts and molds. However, heating at 85 C for 15 min resulted in spore germination. Bacterial counts as high as 107 were observed for aerobic mesophiles and halophiles. Heating above 95 C for 15 min resulted in complete inactivation of surface microflora. Bacteria belonging to Bacillaceae, Paenibacillaceae, Moraxellaceae and Enterobacteriaceae family were identified by 16S rRNA sequencing. In vitro antimicrobial activity of the methanolic extracts of the seaweed on …


Visible Near-Infrared Hyperspectral Imaging For The Identification And Discrimination Of Brown Blotch Disease On Mushroom (Agaricus Bisporus) Caps, Edurne Gaston, Jesus Maria Frias, Patrick J. Cullen, Colm O’Donnell, Aoife Gowen Jan 2010

Visible Near-Infrared Hyperspectral Imaging For The Identification And Discrimination Of Brown Blotch Disease On Mushroom (Agaricus Bisporus) Caps, Edurne Gaston, Jesus Maria Frias, Patrick J. Cullen, Colm O’Donnell, Aoife Gowen

Articles

Brown blotch, caused by pathogenic Pseudomonas tolaasii (P. tolaasii), is the most problematic bacterial disease in Agaricus bisporus mushrooms. Although it does not cause any health problems, it reduces the consumer appeal of mushrooms in the market place, generating important economical losses worldwide. Hyperspectral imaging (HSI) is a non-destructive technique that combines imaging and spectroscopy to obtain information from a sample. The objective of this study was to investigate the use of HSI for brown blotch identification and discrimination from mechanical damage on mushrooms. Hyperspectral images of mushrooms subjected to i) no treatment, ii) mechanical damage or iii) …


The Feasibility Of Producing Vacuum-Packed Fermented Vegetable Products., Antoni Llovera Jan 2008

The Feasibility Of Producing Vacuum-Packed Fermented Vegetable Products., Antoni Llovera

Masters

The average intake of vegetables in Ireland falls below the recommendations of Bord Glas and FSAI. Carrots are the third most consumed vegetable in Ireland and they are an excellent source of vitamins A and B as well as phytochemicals. Lactic acid bacteria (LAB) are well-known in food for their benefits such as improvement of the nutritional value of food and improvement of the digestion of lactose. Vegetable consumption could be enhanced by promoting a novel snack fermented carrot product that would provide the healthy benefits of vegetables coupled with the benefits of the probiotic lactic acid bacteria. Two varieties …


Characteristics Of Cooked Chickpeas And Soybeans During Combined Microwave–Convective Hot Air Drying, Aoife Gowen, Nissreen Abu-Ghannam, Jesus Maria Frias, Jorge Oliveira Jan 2007

Characteristics Of Cooked Chickpeas And Soybeans During Combined Microwave–Convective Hot Air Drying, Aoife Gowen, Nissreen Abu-Ghannam, Jesus Maria Frias, Jorge Oliveira

Articles

Moisture content, shrinkage, water activity (Aw), color and texture of cooked chickpeas and soybeans during convective, microwave and combined microwave–convective drying were studied. Combined drying was significantly (P < 0.05) faster than either convective or microwave drying, and resulted in less shrinkage of the dehydrated product. Rapid burning occurred when samples were dried below a Aw of 0.27 ± 0.07 for chickpeas (P < 0.05), and 0.13 ± 0.04 for soybeans (P < 0.05). Both chickpeas and soybeans displayed a transitional behavior in texture when dried to a Aw below 0.40 ± 0.10 (P < 0.05) for chickpeas, and below 0.63 ± 0.15 (P < 0.05) for soybeans, when samples became brittle. Shelf stable dehydrated chickpea and soybean products with low water activity (Aw = 0.35) and good visual quality could be obtained within 14 min of combination drying.


Influence Of Novel Preservation Methods On The Quality Of Minimally Processed Iceberg Lettuce And Carrot, Daniel Rico Nov 2006

Influence Of Novel Preservation Methods On The Quality Of Minimally Processed Iceberg Lettuce And Carrot, Daniel Rico

Doctoral

The market of ready-to-fresh vegetables has grown rapidly in recent decades as a result of changes in consumer attitudes. Chlorine solutions are widely used to sanitise fresh-cut fruit and vegetables in the industry. However, the possible formation of carcinogenic chlorinated compounds in water has called into questions the use of chlorine in food processing plants. There is a real need to find new alternatives fro the preservation of minimal processed vegetables in order to maintain their quality attributes after processing. The aim of this study was to examine the influence of novel preservation methods on the quality of minimally process …


Compositional Changes In Selected Minimally Processed Vegetables, Emer O'Reilly Jan 2000

Compositional Changes In Selected Minimally Processed Vegetables, Emer O'Reilly

Masters

Compositional, physiological and microbiological changes in selected minimally processed vegetables packaged under a modified atmosphere of 2% oxygen and 5% carbon dioxide were monitored over a ten day storage period at 40 C and 80 C. The analysis targeted specific changes in the nutritional, chemical and physiological make up of the vegetables as well as the changes in the microbial levels. In addition the changes in the gas atmospheres within the packs were monitored. It has been widely accepted that modified atmospheres used to package fresh produce can preserve the product quality and thus extend the shelf life of the …