I think that fat, protein, carbohydrate and other nutrients which are determined in the fruits that are normally eaten with their seeds (berries in general) do not match nutritionally (estimated in excess) to those that are actually available to the body, because the seeds pass mostly unchanged through the digestive system.
I believe that the actions of solvents/acids in analytical determinations are much more effective, especially if the samples are prepared in advance with mill. Does anyone have any experience or data about this?
That is a complex question. I don't know the exact answer, but you must considered that absorption and availability will be influenced by other factors besides the content in the seeds and that they may be different for different nutrients. For instance, berries are very high in phenolic compounds, some of which are able to sequester iron, reducing its availability. Other foods ingested along with berries will also influence nutrient absorption.
What I want to put in evidence is the fact that the nutritional tables should specify whether the data refer to the whole fruit including the seeds milled and analyzed jointly, or only to the pure fruit pulp.
In the nutrition table the analytical values of berries correspond to the eatable part. If the seeds may be available to the body, but it is not common of using them, so they are not counted. Also the thermal units are not measured in a calorimeter, but calculated with formulars from the analysed other parts.
I am in agreement with you for plums, apricots, cherries, peaches, .... but what do you think of raspberries, blueberries, currants, strawberries, ...? I never find nutritional tables with information on the method of preparation of these fruits before chemical analysis.
I think it more likely the presence of the component of seeds in the analytical values rather than the digestibility of the seeds themselves, however small,but always consumed.
In the literature Souci, Fachmann, Kraut: Food composition and nutrition tables. MedPharm Scientific Publishers, 2008. "All values refer to the edible portion of the food product in its marketable form calculated as follows: raw product as purchased minus waste. In the table the waste is given as a percentage of the raw product... In this condition food items may contain parts which must be removed prior to further processing. The remainder is the edible portion.
Hi Ingo,
I do not doubt that this is true by the authors you mentioned. But I fear that this is not the general rule of all nutritional tables that are published.
Thanks anyways.
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