Do you need the process of digestion for carbohidrates? Because if that is what you need then I will post it right away.

What I really want are studies in which starch and/or disaccharides (maltose or sucrose) were compared or considered.

If you dont find more information on children you can address your question by giving a look over studies on piglets which you can easilly find on internet.

@ Piero Susmel: Any idea if the amylase synthesis similar in human infants and piglets?

@Pedro Beyer: Please could you send me the title for those articles if possible?

You have also to take into consideration the intestinal maltase. I'm not sure, but non reason to assume that pancreatic and intestinal synthetic ways of amylase and maltase in monogastric should differ. What changes is the time required for developing an efficent synthesis of enzymes, which mainly depends upon age at weaning. Infants takes longer to develop a functional GI. The piglet body at birth in more "mature" or is at a higher level of development tnan a baby.

@Piero Susmel: Thanks very much. More reading for me. Thanks very much

There is very little direct measurement in infants . It is difficult to do studies in human infants without stable isotopes.

But you may find the following useful

Christian MT, Edwards CA, Preston T, Johnston LA, Varley R, Weaver LT. Patterns of colonic starch fermentation from infancy to adulthood. Eur J Clin Nutr 2003 57 1486-91

Christian M, Edwards C, Weaver LT.

J Pediatr Gastroenterol Nutr. 1999 Aug;29(2):116-24.

Starch digestion in infancy.

Weaver LT, Dibba B, Sonko B, Bohane TD, Hoare S.

Br J Nutr. 1995 Oct;74(4):531-7.

Measurement of starch digestion of naturally 13C-enriched weaning foods, before and after partial digestion with amylase-rich flour, using a 13C breath test.

Thanks Christine, I have read those quality papers on yours. I am considering the method described by Singh below: Singh, U., M.S. Kherdekar, and R. Jambunathan, Studies on desi and kabuli chickpea (Cicer arietinum L.) cultivars. The levels of amylase inhibitors, levels of oligosaccharides and in vitro starch digestibility. Journal of Food Science, 1982. 47(2): p. 510-512.

It is underestimating low digestibility for foods containing significant amount of maltose as carbohydrate than starch. Any take on this.

Dear Francis

I do not understand your question entirely, the paper you mention was really looking at potential causes of flatulence and tested whether the amylase inhibitors in chick peas were responsible which they found with non heated flour but not flour heated for ten minutes. In fact it is probably the fermentation of the non digestible oligosaccharides that cause the flatulence.

The digestion of maltose takes place on the brush border of the mucosa with the enzyme maltase. If you explain your main issue at little more I may be able to advise better.

Dear Christine,

I am considering the starch digestibility method, other researchers are using that method to estimate digestibility of foods, both for adults and young children.

However, I applied the method "as is" to two different food samples: (1) high in endogenous maltose and low in starch; and (2) high in starch and low in endogenous maltose.

I expected the one with the relatively high level of endogenous maltose to have higher digestibility, but this was not case.

Hope it is clearer now for you to offer your advice.

Rgds,

Francis.

OK so we need to consider your model. What is the outcome measure? By this I mean the end product that you are testing to say digestion has occured. In the paper it states they used equivalents of maltose released as the end point. If you are using maltose in your test foods this may confuse the final result. Also with high levels of maltose you may get some product inhibition of the enzyme. You could use a different protocol of the type used to estimate resistant starch which uses a range of enzymes including amyloglucosidase to convert all CHO to glucose for final assay.

A recent example of this is in the publication below

Mkandawire NL, Kaufman RC, Bean SR, Weller CL, Jackson DS, Rose DJ.

Effects of Sorghum (Sorghum bicolor (L.) Moench) Tannins on α-Amylase Activity and in Vitro Digestibility of Starch in Raw and Processed Flours.

J Agric Food Chem. 2013 May 8;61(18):4448-54. doi: 10.1021/jf400464j. Epub 2013 Apr 29.

This should remove any inhibitory effects and convert the maltose to glucose.

There are more simple versions of these types of assay which look at resistant starch which may be easier to implement.

For example

Goni I, Garcia-Diz L, Manas E and Saura-Calixto F, Analysis of resistant

starch: A method for foods and food products. Food Chem

56:445–449 (1996).

Hope this helps

Thank you very much Christine. My dilemma: I have collected data already using maltose as the marker of digestion as in Singh as others have cited. I realised that I was getting product inhibition of the amylase. I did a recovery of pure maltose using Singh method and it the recovery was only about 40%!

I am considering to publish a paper to show that the Singh method may falsely predict low digestibility if food samples contain endogenous maltose.

I would be stating that foods higher in maltose (or levels of simple sugars) than starch should be easily digested by infants, but the Singh method does not.

Do you think it is worth trying.

You comments, please

Rgds,

Francis.

This sounds interesting. Obviously I cannot comment on the quality of the data as I have not seen it but if people are likely to be using the Singh method then this is a very valid point.

Thank you.