Now showing 1 - 10 of 13
  • Publication
    Quality degradation kinetics of fresh strawberries exposed to different levels of relative humidity
    Strawberry 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.
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  • Publication
    An investigation into the efficacy of ozone for inactivation of microalgae cells in photobioreactors
    (American Society of Agricultural and Biological Engineers (ASABE), 2013-07) ; ; ; ;
    The 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.
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  • Publication
    Optimisation of Ultrasound Frequency, Extraction Time and Solvent for the Recovery of Polyphenols, Phlorotannins and Associated Antioxidant Activity from Brown Seaweeds
    This study investigates ultrasound assisted extraction (UAE) process parameters (time, frequency and solvent) to obtain high yields of phlorotannins, flavonoids, total phenolics and associated antioxidant activities from 11 brown seaweed species. Optimised UAE conditions (35 kHz, 30 min and 50% ethanol) significantly improved the extraction yield from 1.5-fold to 2.2-fold in all seaweeds investigated compared to solvent extraction. Using ultrasound, the highest recovery of total phenolics (TPC: 572.3 ± 3.2 mg gallic acid equivalent/g), total phlorotannins (TPhC: 476.3 ± 2.2 mg phloroglucinol equivalent/g) and total flavonoids (TFC: 281.0 ± 1.7 mg quercetin equivalent/g) was obtained from Fucus vesiculosus seaweed. While the lowest recovery of TPC (72.6 ± 2.9 mg GAE/g), TPhC (50.3 ± 2.0 mg PGE/g) and TFC (15.2 ± 3.3 mg QE/g) was obtained from Laminaria digitata seaweed. However, extracts from Fucus serratus obtained by UAE exhibited the strongest 1,1-diphenyl-2-picryl-hydrazyl (DPPH) scavenging activity (29.1 ± 0.25 mg trolox equivalent/g) and ferric reducing antioxidant power (FRAP) value (63.9 ± 0.74 mg trolox equivalent/g). UAE under optimised conditions was an effective, low-cost and eco-friendly technique to recover biologically active polyphenols from 11 brown seaweed species.
      139Scopus© Citations 57
  • Publication
    Vibrational Spectroscopy for Analysis of Water for Human Use and in Aquatic Ecosystems
    Maintaining 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.
      4413Scopus© Citations 23
  • Publication
    Blueberry supply chain: Critical steps impacting fruit quality and application of a boosted regression tree model to predict weight loss
    Blueberries have increased in popularity in recent years due to their nutritional benefits and sensory characteristics. However, to preserve quality and extend shelf-life, they need to be maintained at refrigerated temperatures and high relative humidity, conditions that are not routinely met along the supply chain. Poor temperature management leads to quality deterioration, increasing waste/losses along the supply chain. This study examined the impact of each step along the supply chain on the physichochemical quality and shelf-life of blueberries, identifying the most critical steps from field to consumption. The following steps were identified as critical in the blueberry supply chain: shipping to distribution centre (DC) (72 h at 5 °C), store display (48 h at 15 °C), and consumer (48 h at 20 °C). Given the economic importance of weight loss and its link to fruit quality and shelf-life, a boosted regression tree (BRT) model was built to predict weight loss using the post-harvest environmental conditions of a simulated supply chain applying different temperature-time scenarios. The model explained 84 % of the variance on the test set and highlighted the interactions of supply chain conditions on weight loss.
      69Scopus© Citations 15
  • Publication
    Green extraction of proteins, umami and other free amino acids from brown macroalgae Ascophyllum nodosum and Fucus vesiculosus
    Seaweeds are a valuable potential source of protein, as well as free amino acids (FAAs) with umami flavour which are in high demand by the food industry. The most commonly used flavouring agents in the food industry are chemically synthesised and therefore are subject to concerns regarding their safety and associated consumer resistance. This study focuses on the effects of extraction time (1 and 2 h) and solvents (0.1 M HCl, 1% citric acid and deionised water) on the extraction of protein and FAAs including umami FAAs from Irish brown seaweeds (Ascophyllum nodosum and Fucus vesiculosus). Extraction yields were influenced by both the extraction solvent and time, and also varied according to the seaweed used. Both seaweeds investigated were found to be good sources of protein, FAAs including umami FAAs, demonstrating potential application as flavouring agents in the food industry. Overall, the use of green solvents (deionised water and citric acid) resulted in higher recoveries of compounds compared to HCl. The results of this study will facilitate the use of more sustainable solvents in industry for the extraction of proteins and flavouring agents from seaweed.
      99Scopus© Citations 4
  • Publication
    Modelling the biochemical and sensory changes of strawberries during storage under diverse relative humidity conditions
    Many 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.
      377Scopus© Citations 26
  • Publication
    Global food security – Issues, challenges and technological solutions
    Background: 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.
      3249Scopus© Citations 106
  • Publication
    Emerging food processing technologies and factors impacting their industrial adoption
    Innovative 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.
      899Scopus© Citations 83
  • Publication
    The value of seaweed
    TEAGASC researchers are developing zero waste industry processes to generate high-value-added products from seaweed.
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