O'Donnell, C. P. (Colm P.)
O'Donnell, C. P. (Colm P.)
O'Donnell, C. P. (Colm P.)
Now showing 1 - 10 of 13
- PublicationProduction of medicated bedding straw: challenges and perspectivesPrevious bacteriological findings have reported that animal disease outbreaks are associated with the quality of the animal environment. Animal bedding straw is a good source of bacteria and fungi, typically contaminated with (mycelia) yeasts and filamentous fungi species such as Aspergillus, Fusarium, Alternaria, Cladosporium, Epicoccum, Penicillium, Verticillium and Enterobacteria. The objective of this work was to assess the efficacy of different technologies on the production of medicated bedding straw. Four critical control points of an industrial straw disinfection processing line were identified. The levels of fungi and bacteria present in the straw during an industrially applied mechanical – chemical process were quantified. The plate counting revealed that propionic acid and formaldehyde chemicals reduced the microbial levels from the raw material and that they were more efficient on moulds than on bacteria. The potential use of ozone gas as an alternative greener technology to the current liquid chemical treatments was also evaluated. Trials conducted on ozone treatments (flow rates: 0.031, 0.125, 0.5 L/min, concentrations: 36, 99, 150 μg/mL, treatment time: 0, 5, 15, 30 mins, and residual times of 0 to 18 hrs) indicated that ozone successfully reduces the microbial counts and the fungi levels by more than 1.5 logs (cfu/g).
- PublicationAn investigation into the efficacy of ozone for inactivation of microalgae cells in photobioreactorsThe sterilisation of photobioreactors is paramount to successful cultivation of microalgae. Due to the adhesive nature of microalgae, fouling of the light transmitting surfaces can be problematic. Traditional methods of sterilising photobioreactors between batches involve ultrasound, autoclaving or as seen in recent times, the photobioreactor incorporates a cleaning system. The objective of this project was to look at an alternative method of sterilisation. A preliminary study was carried out to determine the efficacy of ozone as treatment for the algae strain Dunaliella tertiolecta. Algae cultures at 104 cells CFU mL-1 were exposed to 3-51 μg mL-1 of ozone at different time periods (0-80 sec) and constant gas flow rates of 0.125 and 0.25 L min -1. Inactivation rates for total reduction of D. tertiolecta were found to increase significantly with an increase in ozone concentration and treatment time. This study supports the proposed mechanism of cell inactivation by ozone that causes cell membrane destruction and finally cell death. Therefore, it was found that ozone can be used to effectively eradicate microalgae in photobioreactors.
- PublicationUse of an NIR MEMS spectrophotometer and visible/NIR hyperspectral imaging systems to predict quality parameters of treated ground peppercornsThe aim of this study was to investigate the potential of a micro-electromechanical NIR spectrophotometer (NIR-MEMS) and visible (Vis)/NIR hyperspectral imaging (HSI) systems to predict the moisture content, antioxidant capacity (DPPH, FRAP) and total phenolic content (TPC) of treated ground peppercorns. Partial least squares (PLS) models were developed using spectra from peppercorns treated with hot-air, microwave and cold plasma. The spectra were acquired using three spectroscopy systems: NIR-MEMS (1350–1650 nm), Vis-NIR HSI (450–950 nm) and NIR HSI (957–1664 nm). Very good predictions of TPC (RPD > 3.6) were achieved using NIR-MEMS. The performance of models developed using Vis-NIR HSI and NIR HSI were good or very good for DPPH (RPD > 3.0), FRAP (RPD >2.9) and TPC (RPD > 3.8). This study demonstrated the potential of NIR-MEMS and Vis-NIR/NIR HSI to predict the moisture content, antioxidant capacity and total phenolic content of peppercorns. The spectroscopy technologies investigated are suitable for use as in-line PAT tools to facilitate improved process control and understanding during peppercorn processing.
Scopus© Citations 15 255
- PublicationUltrasound-assisted processing of Chlorella vulgaris for enhanced protein extractionThe green microalga Chlorella vulgaris is a promising source of proteins of high nutritional value for the food industry. The present study aims to improve the recovery of proteins and umami free amino acids from C. vulgaris by exploring the use of ultrasound following multiple approaches including ultrasound-assisted single solvent extraction, ultrasound-assisted sequential solvent extraction and ultrasound-assisted enzymatic extraction. Ultrasound-assisted single solvent extraction using an alkaline solvent during 10 min provided equivalent protein recoveries to those obtained in control experiments macerating the biomass during 18 and 24 h. Ultrasound-assisted sequential solvent extraction using 0.4 M NaOH followed by 0.4 M HCl achieved a protein recovery of 79.1 ± 5.3%, 1.32-fold higher than the control experiments without ultrasound for 1 h. Ultrasound-assisted enzymatic extraction using lysozyme resulted in protein recoveries ranging from 33 to 42%, and these extracts also contained a high percentage of umami free amino acids. Ultrasound-assisted enzymatic extraction with protease enhanced the recovery of proteins (58–82%), although the extracts had low percentage of umami free amino acids. The scanning electron microscopy imaging revealed that ultrasound-assisted solvent extraction and ultrasound-assisted enzymatic extraction significantly changed the morphology of the cell surface.
Scopus© Citations 63 736
- PublicationVibrational Spectroscopy for Analysis of Water for Human Use and in Aquatic EcosystemsMaintaining a clean water supply is one of the key challenges facing humanity today. Pollution, over-use and climate change are just some of the factors putting increased pressure on our limited water resources. Contamination of the water supply presents a high risk to public health, security and the environment; however, no adequate real-time methods exist to detect the wide range of potential contaminants. There is a need for rapid, low cost, multi target systems for water quality monitoring. Information rich techniques such as vibrational spectroscopy have been proposed for this purpose. This review presents developments in the applications of vibrational spectroscopy to water quality monitoring over the past 20 years, identifies emerging technologies and discusses future challenges.
Scopus© Citations 25 4821
- PublicationQuality degradation kinetics of fresh strawberries exposed to different levels of relative humidityStrawberry is a popular fruit globally and one most often discarded throughout the supply chain, due to high perishability and poor management during distribution. Throughout the supply chain strawberries are kept at temperatures and relative humidity (RH) conditions that deviate significantly from the optimum. Many studies stress the importance of keeping strawberries at 90-95% RH but the effect of the deviations occurring during the supply chain on the appearance, acceptability and quality of strawberries has not been explored to date.
- PublicationGlobal food security – Issues, challenges and technological solutionsBackground: Food security is both a complex and challenging issue to resolve as it cannot be characterized or limited by geography nor defined by a single grouping, i.e., demography, education, geographic location or income. Currently, approximately one billion people (16% of global population) suffer from chronic hunger in a time when there is more than enough food to feed everyone on the planet. Therein lies the Food security challenge to implement an ability to deal with increasing food shortages, caused by a combination of waste and an ever expanding world population. At current levels prediction state that we must increase global food production by 70% on already over exploited finite infrastructures before 2050. Scope and approach: This review paper firstly introduces the concept of Food Security with an overview of its scale and depth in the context of the global food industry. It then highlights the main sources. The readership is then introduced to the key factors affecting food security and highlights the many national and international measures adopted to tackle the problem at both policy and technological level. Key findings and conclusions: Food experts indicate that no one single solution will provide a sustainable food security solution into the future. Collective stakeholder engagement will prove essential in bringing about the policy changes and investment reforms required to achieve a solution. Achieving truly sustainable global food security will require a holistic systems-based approach, built on a combination of policy and technological reform, which will utilize existing systems combined with state-of-the-art technologies, techniques and best practices some of which are outlined herein.
Scopus© Citations 168 3933
- PublicationModelling the biochemical and sensory changes of strawberries during storage under diverse relative humidity conditionsMany studies stress the importance of keeping strawberries at high relative humidity conditions during postharvest storage. However, the effect of deviations occurring across the supply chain on the appearance, acceptability and biochemical properties of strawberries has not been adequately explored or quantified to date using kinetic modelling applications. This study investigated the effect of relative humidity (RH)on degradation kinetics of quality and biochemical properties of ‘Strawberry Festival’, during 7 days of storage at 2 °C, using zero, first-order and Weibull models. The strawberries were stored at 40, 60, 70, 80 or 90% RH and were evaluated using subjective quality evaluation, weight loss monitoring and biochemical analysis. The shelf life was established based on current industry practices using subjective quality evaluation, namely shrivelling and colour scores. The Weibull model was found to better fit the experimental chemical analysis data compared to zero and first order kinetics models. The analysis of the rate constants quantified the significant effect of RH conditions on the weight loss and degradation rate of chemical components. Storage at low RH conditions accelerated the loss of ascorbic acid, and anthocyanins and negatively affect the in vitro antioxidant activity. The overall appearance of strawberries was modelled with zero-order kinetic model and the results revealed that lower RH conditions can limit the remaining shelf life of fresh strawberries by increasing the rate of appearance deterioration. Using RH and time as predictors in a logistic regression model, the waste occurring due to unacceptable strawberry quality, was predicted; highlighting the importance of using RH in predictive modelling when designing supply chains with the view to minimise losses.
Scopus© Citations 31 450
- PublicationEmerging food processing technologies and factors impacting their industrial adoptionInnovative food processing technologies have been widely investigated in food processing research in recent years. These technologies offer key advantages for advancing the preservation and quality of conventional foods, for combatting the growing challenges posed by globalization, increased competitive pressures and diverse consumer demands. However, there is a need to increase the level of adoption of novel technologies to ensure the potential benefits of these technologies are exploited more by the food industry. This review outlines emerging thermal and non-thermal food processing technologies with regard to their mechanisms, applications and commercial aspects. The level of adoption of novel food processing technologies by the food industry is outlined and the factors that impact their industrial adoption are discussed. At an industry level, the technological capabilities of individual companies, their size, market share as well as their absorptive capacity impact adoption of a novel technology. Characteristics of the technology itself such as costs involved in its development and commercialization, associated risks and relative advantage, and level of complexity and compatibility influence the technology's adoption. The review concludes that a deep understanding of the development and application of a technology along with the factors influencing its acceptance are critical to ensure its commercial adoption.
Scopus© Citations 115 1161