|
|
|
|
|
| Søltoft, Malene; Nielsen, J.; Laursen, Kristian Holst; Husted, Søren; Halekoh, Ulrich; Knuthsen, Pia. |
| The demand for organic food products is steadily increasing partly due to the expected health benefits of organic food consumption. Polyphenols, such as flavonoids and phenolic acids, are a group of secondary plant metabolites with presumably beneficial health effects, and contents in plants are affected by, for example, plant nutrient availability, climate, pathogen infection, and pest attack. In the current study, onions, carrots, and potatoes were cultivated in two-year field trials in three different geographical locations, comprising one conventional and two organic agricultural systems. The contents of flavonoids and phenolic acids in plants were analyzed by pressurized liquid extraction and high-performance liquid chromatography−ultraviolet... |
| Tipo: Journal paper |
Palavras-chave: "Organics" in general; Food systems. |
| Ano: 2010 |
URL: http://orgprints.org/19119/4/19119.pdf |
| |
|
|
| Søltoft, Malene; Eriksen, M.R.; Träger, A.W.B.; Nielsen, J.; Laursen, Kristian Holst; Husted, Søren; Halekoh, Ulrich; Knuthsen, Pia. |
| A rapid and sensitive analytical method for quantification of polyacetylenes in carrot roots was developed. The traditional extraction method (stirring) was compared to a new ultrasonic liquid processor (ULP)-based methodology using high-performance liquid chromatography−ultraviolet (HPLC−UV) and mass spectrometry (MS) for identification and quantification of three polyacetylenes. ULP was superior because a significant reduction in extraction time and improved extraction efficiencies were obtained. After optimization, the ULP method showed good selectivity, precision [relative standard deviations (RSDs) of 2.3−3.6%], and recovery (93% of falcarindiol) of the polyacetylenes. The applicability of the method was documented by comparative analyses of carrots... |
| Tipo: Journal paper |
Palavras-chave: Food systems. |
| Ano: 2010 |
URL: http://orgprints.org/19121/4/19121.pdf |
| |
|
|
| Søltoft, Malene; Christensen, J.H.; Nielsen, J.; Knuthsen, Pia. |
| A rapid and reliable analytical method for quantification of flavonoids in onions was developed and validated. Five extraction methods were tested on freeze-dried onions and subsequently high performance liquid chromatography (HPLC) with UV detection was used for quantification of seven flavonoids. The extraction efficiencies were lowest for the conventional water bath extraction compared to pressurized liquid extraction (PLE), ultrasonication, ultrasonic liquid processor, and microwave extraction, which yielded similar efficiencies. The reproducibility was in the same range (RSD: 1–11%) for all tested extraction methods. However, PLE was the preferred extraction method because the method can be highly automated, use only small amounts of solvents,... |
| Tipo: Journal paper |
Palavras-chave: Research methodology and philosophy. |
| Ano: 2009 |
URL: http://orgprints.org/19117/4/19117.pdf |
| |
|
|
| Søltoft, Malene; Bysted, A.; Madsen, K.H.; Mark, Alicja Budek; Bügel, Susanne; Nielsen, J.; Knuthsen, Pia. |
| BACKGROUND: The demand for organic food products has increased during the last decades due to their probable health effects, among others. A higher content of secondary metabolites such as carotenoids in organic food products has been claimed, though not documented, to contribute to increased health effects of organic foods. The aim was to study the impact of organic and conventional agricultural systems on the content of carotenoids in carrots and human diets. In addition, a human cross-over study was performed, measuring the plasma status of carotenoids in humans consuming diets made from crops from these agricultural systems. RESULTS: The content of carotenoids in carrot roots and human diets was not significantly affected by the agricultural... |
| Tipo: Journal paper |
Palavras-chave: Food systems. |
| Ano: 2011 |
URL: http://orgprints.org/19120/4/19120.pdf |
| |
|
|
| Husted, Søren; Laursen, Kristian Holst; Larsen, Erik Huusfeldt; Kapolna, Emese; Knuthsen, Pia; Søltoft, Malene; Bügel, Susanne; Mark, Alicja Budek; Lauridsen, Charlotte; Jacobsen, Maja; Jørgensen, Henry; Halekoh, Ulrich; Kristensen, Kristian. |
| Trace elements, bioactive secondary metabolites and vitamins are among the most important quality parameters in plants. Yet, very little information is available on their content, bioavailability and health effects in organically grown plant food products. The main objective of OrgTrace is to study the impact of different agricultural management practices relevant for organic farming on the ability of cereal and vegetable crops to absorb trace elements from the soil and to synthesize bioactive compounds (secondary metabolites, antioxidant vitamins and phytates) with health promoting effects. Based on different plant products produced in OrgTrace, diets were composed and the bioavailabilities of health promoting substances were analyzed in a human... |
| Tipo: Conference paper, poster, etc. |
Palavras-chave: "Organics" in general; Farming Systems; Soil; Food systems. |
| Ano: 2011 |
URL: http://orgprints.org/18877/4/18877.pdf |
| |
|
| |
|
|
|
