The effect of processing on in vitro starch digestion rate of cereal grains depends on species

Helle Nygaard Lærke*, Laura Rasmussen, Nuria Canibe, Mette Skou Hedemann

*Corresponding author af dette arbejde

Publikation: Bidrag til tidsskrift/Konferencebidrag i tidsskrift /Bidrag til avisKonferenceabstrakt i tidsskriftForskningpeer review


The digestive capacity of newly weaned piglets is low. Therefore, highly digestible feed ingredients may increase growth and reduce the risk of weaning diarrhoea.
The value of heat processing as a measure to increase the digestibility and rate of digestion may depend on processing conditions as well as the intrinsic structure of starch and its integrity with other constituents of the grain. We hypothesized that the same processing procedure on in vitro rate and extent of starch digestion would affect cereal species differently.
Batches of wheat, barley, oats (hulled and dehulled), corn and rye were analyzed raw and after one or more different single-batch treatments, i.e., expanded, cold- or warm-pelleted, extruded, puffed, or flaked for their starch digestion properties. In vitro starch digestion rate was determined in triplicate by glucose release after initial incubation with pepsin, followed by pancreatin for 10, 20, 30, 60 and 120 min, and final treatment with KOH and amyloglucosidase. The triplets were used to model starch digestion kinetics by a mechanistic growth model and described by the digestion rate constant (k), the equilibrium constant (asymptote, a) and the total digestion area under the curve (AUC).
The most profound and consistent effect was seen on the k-value, with all heat treatments increasing k 93-532 %. Extruded and puffed grains had 118-172 % higher k-values than cold and warm pelleted grains and expanded products 40-59 % higher values. Pelleted and flaked corn had 367-487 % higher k-values than raw corn. For oats, k was twice as high for warm compared to cold pelleting, which was not observed to the same extent for the other grains. Oats also had a 109 % higher initial k-value than wheat, barley and corn. In conclusion, the benefit of heat treatment depended on the grain species.
TidsskriftAnimal - Science proceedings
Sider (fra-til)171-171
Antal sider1
StatusUdgivet - jul. 2022
BegivenhedDigestive Physiology of Pigs 2022 - Rotterdam, Holland
Varighed: 17 maj 202220 maj 2022


KonferenceDigestive Physiology of Pigs 2022