Analysis of quality and nutritional content in field cress and potatoes

Last changed: 06 July 2017
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What they contain and how healthy they are, for both humans and livestock, is of vital importance for how usable different crops are as food. This may concern nutritional content, composition of starch and fatty acids, or regard specific substances which are more or less beneficial if ingested

Seed analysis in field cress

We have previously analysed the oil quality in seeds and larger components such as polysaccharides in the cell walls of the field cress. We are now continuing with other parts of the seed, examining the nutrition in the residual product (the seed cake) after oil extraction, in order to see if the seed cake can be used as animal feed. The composition of fibres plays an important part for the seed cake's nutritional value and pre-biotic properties.

We are also looking at different phenols which, for example, may have antioxidant properties. Certain phytosterols have proven to reduce the cholesterol value in blood and have previously shown that the field cress seeds contain high levels of these substances. Tocopherols (TCP, E-vitamins) are antioxidants that, besides being beneficial to us humans, are also of vital importance for the oil's stability. We analyse the glucosinolate content of the seed cake. Glucosinolates are substances that are poisonous at high levels, but that have positive effects at low levels.  

Contact: Lena Dimberg

Analysis of starch in potatoes

Starch in potatoes consists of amylose and amylopectin. Even small increases of amylose give a significantly lower glycemic index (GI), but the total GI value is also affected by the amount of available glucose in the potatoes. Therefore, we want to achieve a high starch level and at the same time maintain a high level of amylose. Earlier analyses of potatoes developed in the project do not only show a higher level of amylose, but also that the amylopectin had developed an interesting structure which should prove to be useful in the production of new, environmentally friendly plastics.

We are currently analysing the nutritional value of the starch with high amylose levels, and testing to what extent the special starch can resist enzymatic degradation. We are also characterising the two starch types to understand the connection between structure and function at molecular level.

Contact: Roger Andersson

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