104 research outputs found
Effect of organic and conventional cultivation techniques on yield, phenolic content, and sensory parameters in two carrot varieties
conference paperCarrots are one of the most important field grown vegetables in Ireland with a farm gate value of 16 million euros in 2007. They contain health promoting bioactive compounds including carotenoids, phenolics and
polyacetylenes. Organically grown vegetables are often perceived as healthier and to have better flavour. The objective of this study was to determine levels of phenolics and flavonoids in organic and conventionally
grown carrots, and to determine if they can be distinguished by taste.The Department of Agriculture, Fisheries and Food
(FIRM 06/NITARFC6) is gratefully acknowledged for
financial support of this wor
Sensory and ATP derivative-based indicators for assessing the freshness of Atlantic salmon (Salmo salar) and cod (Gadus morhua)
peer-reviewedIrish Journal of Agricultural and Food Research | Volume 58: Issue 1
Sensory and ATP derivative-based indicators for assessing the freshness of Atlantic salmon (Salmo salar) and cod (Gadus morhua)
Colin Fogarty
, Conor Smyth
, Paul Whyte
, Nigel Brunton
and Declan Boltonemail
DOI: https://doi.org/10.2478/ijafr-2019-0008 | Published online: 31 Oct 2019
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Abstract
To estimate the shelf life of fresh fish, the processor must know the period of time between catch/harvest and arrival at the processing plant. This information is not always available, necessitating the provision of methods to estimate the time since catch or harvest. The objectives of this study were therefore to develop and/or validate sensory and ATP derivative-based methods for rapidly assessing the freshness of fish. A quality index method (QIM; raw fish) and a quantitative descriptive analysis (QDA; cooked fish) were developed and validated (against bacterial count [total viable count (TVC)] and time) for salmon (Salmo salar) and cod (Gadus morhua). The production of inosine monophosphate (IMP), inosine and hypoxanthine (Hx) and associated ratios (IMP/Hx, K1-value or H-value) were also investigated for use as freshness markers. There was a linear relationship between QIM and TVC (R2 = 0.93 for salmon and R2 = 0.89 for cod), QIM and time (R2 = 0.96 for salmon and R2 = 0.98 for cod), QDA and TVC (R2 = 0.93 for salmon and R2 = 0.77 for cod) and QDA and time (R2 = 0.94 for salmon and R2 = 0.87 for cod), suggesting that the QIM and QDA schemes developed could be used to monitor/assess freshness. The H-value also increased linearly with TVC (R2 = 0.88 for salmon and R2 = 0.89 for cod) and time (R2 = 0.93 for salmon and R2 = 0.84 for cod). It was therefore concluded that both the QIM/QDA approach and monitoring ATP degradation, specifically expressed as the H-value, could be used as rapid methods to assess the freshness of salmon and cod arriving at the processing plan
Comparison of phenolic and flavonoid content and antioxidant activity in vitro among potato varieties.
Conference paperDiets rich in fruits and vegetables have been associated with a lower incidence of cancer and heart disease, which may be related to the antioxidant activity of
bioactive compounds present in these foods. Phenolic compounds are potent antioxidants in vitro, of which flavonoids are of particular interest for their potential
positive impact on health. Potatoes are one of the most consumed vegetables in the world and therefore an important source of phenolics. In Ireland they are the
third most important crop with a farm gate value of approximately 45 million euros annually. The aim of this work was to evaluate the antioxidant activity of methanolic solutions extracted from the skin
and flesh of potato tubers against the stable radical DPPH and analyze its relationship to the content of
total phenolics and total flavonoids.Teagasc Walsh Fellowship Programm
Absolute Configuration of Falcarinol (9Z-heptadeca-1,9-diene-4,6- diyn-3-ol) from Pastinaca sativa
Falcarinol (9Z-heptadeca-1,9-diene-4,6-diyn-3-ol; 1) is a polyacetylene commonly found in several plant families. The absolute configuration of naturally
occurring 1 is not clear and contradictory results have been reported in the literature. Determination of the absolute configuration of 1 from Pastinaca sativa L.
was carried out. Isolation of 95% pure 1 was performed via successive fractionation and preparative-HPLC. A racemic mixture comprised of 3R-1 and 3S-1
was synthesized in order to confirm the absolute configuration of the isolated natural product using chiral HPLC. Based on a combination of chiral HPLC and
specific rotation, 1 present in P. sativa was found to have a 3R absolute configuration (i.e. (3R, 9Z)-heptadeca-1,9-diene-4,6-diyn-3-ol)
Acrylamide formation in potato products
End of Project ReportAcrylamide, a substance classified as a potential carcinogen, occurs in heated
starchy foods at concentrations many times in excess of levels permitted in
drinking water. Early surveys indicated that levels of acrylamide in potato
products such as French fries and potato crisps were the highest of the
foodstuffs investigated. The present project addressed this issue by
determining levels of acrylamide precursors (asparagine and reducing sugars)
in raw potatoes and levels of acrylamide in (i) potato products from different
storage regimes, (ii) spot-sampled potatoes purchased from a local
supermarket, (iii) samples that received pre-treatments and were fried at
different temperatures and (iv) French fries reheated in different ovens.A risk
assessment of the estimated acrylamide intake from potato products for
various cohorts of the Irish population was also conducted
A note on the effectiveness of selenium supplementation of Irish-grown Allium crops.
peer-reviewedThis study is funded by the Department of Agriculture and Food through the Network and Team Building Initiative of the Food Institutional Research Measure (FIRM Reference Number 06/NITARFC6).Onions and other Allium crops contain high levels of dietary phenolics and, unlike
many other crops, accumulate the beneficial mineral selenium. Selenium-enhanced
Allium crops are of interest both from a public good perspective and as a market
positioning strategy for growers. Field trials were carried out to i) identify onion and
scallion varieties that contain high levels of health-promoting phenolic and flavonoid
compounds as potential targets for selenium supplementation and ii) investigate selenium
supplementation in the widely-grown commercial onion variety ‘Hyskin’ at different
application rates of nitrogen fertilizer. Levels of selenium in onion bulbs were
significantly increased from 0.5–5.9 μg/g dry weight (DW) to 40.6–70.0 μg/g DW.Department of Agriculture, Food and the Marin
Qualitative and Quantitative Analysis of Polyphenols in Lamiaceae Plants—A Review
peer-reviewedLamiaceae species are promising potential sources of natural antioxidants, owing to their high polyphenol content. In addition, increasing scientific and epidemiological evidence have associated consumption of foods rich in polyphenols with health benefits such as decreased risk of cardiovascular diseases mediated through anti-inflammatory effects. The complex and diverse nature of polyphenols and the huge variation in their levels in commonly consumed herbs make their analysis challenging. Innovative robust analytical tools are constantly developing to meet these challenges. In this review, we present advances in the state of the art for the identification and quantification of polyphenols in Lamiaceae species. Novel chromatographic techniques that have been employed in the past decades are discussed, ranging from ultra-high-pressure liquid chromatography to hyphenated spectroscopic methods, whereas performance characteristics such as selectivity and specificity are also summarized
Effect of Drying Methods on the Steroidal Alkaloid Content of Potato Peels, Shoots and Berries
peer-reviewedThe present study has found that dried potato samples yielded significantly higher levels of steroidal alkaloids such as α-solanine and α-chaconine than the corresponding fresh samples, as determined by the UPLC-MS/MS technique. Among the drying techniques used, air drying had the highest effect on steroidal alkaloid contents, followed by freeze drying and vacuum oven drying. There was no significant difference between the freeze dried and vacuum oven dried samples in their α-chaconine contents. However, freeze dried potato shoots and berries had significantly higher α-solanine contents (825 µg/g dry weight (DW) in shoots and 2453 µg/g DW in berries) than the vacuum oven dried ones (325 µg/g dry weight (DW) in shoots and 2080 µg/g DW in berries). The kinetics of steroidal alkaloid contents of potato shoots during air drying were monitored over a period of 21 days. Both α-solanine and α-chaconine content increased to their maximum values, 875 µg/g DW and 3385 µg/g DW, respectively, after 7 days of drying. The steroidal alkaloid contents of the shoots decreased significantly at day 9, and then remained unchanged until day 21. In line with the potato shoots, air dried potato tuber peels also had higher steroidal alkaloid content than the freeze dried and vacuum oven dried samples. However, a significant decrease of steroidal alkaloid content was observed in air dried potato berries, possibly due to degradation during slicing of the whole berries prior to air drying. Remarkable variation in steroidal alkaloid contents among different tissue types of potato plants was observed with the potato flowers having the highest content.This study has been carried out with the financial support from the Potato Peel project
funded under the Food Institutional Research Measure (FIRM, 11F/050; NovTechIng) by the Irish Department of
Agriculture, Food and Marine
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