Normal corn starch was chemically modified by oxidation, acetylation, hydroxypropylation, and cross-linking, and the digestibility and glycemic indices (GI) of these modified starches were examined by in vitro hydrolysis using pancreatic α-amylase. During the early stage of hydrolysis (up to 60 min) with prime (ungelatinized) starches, the modified starches were hydrolyzed at greater extents than the unmodified starches. However, at the late stage of hydrolysis (after 3 h), the modified starches showed lower degrees of hydrolysis than the unmodified starch. The amount of resistant starch (RS) in prime starches were 23.4%, 35.1%, 34.2%, and 13.9% in the acetylated, oxidized, hydroxypropylated, and cross-linked starches, respectively, whereas the unmodified starch contained 11.9%. The amount of slowly digestible starch (SDS) was decreased as the RS content was increased by the modification, indicating that some of the SDS transformed to RS. By gelatinization, all the starches, regardless of type of modification, were more quickly hydrolyzed and reached maximum levels within 20 min. Like the prime starches, the modified starches contained higher contents of undigested starches after gelatinization. The modifications except cross-linking reduced rapidly digestible starch (RDS) content but increased the RS content when the starches were gelatinized. The hydroxypropylated starch had the lowest GI values, which were estimated from the hydrolysis profiles (70.6 and 86.2 in prime and gelatinized states, respectively), whereas the GI values of cross-linked starch were similar to those of the unmodified starch. Therefore, chemical substitution such as hydroxypropylation and acetylation, and oxidation can be used to reduce the starch digestibility and raise the RS content.
Food Research International – Elsevier
Published: Jul 1, 2008
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.
All for just $49/month
Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly
Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.
Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.
Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.
All the latest content is available, no embargo periods.
“Hi guys, I cannot tell you how much I love this resource. Incredible. I really believe you've hit the nail on the head with this site in regards to solving the research-purchase issue.”Daniel C.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud
“I must say, @deepdyve is a fabulous solution to the independent researcher's problem of #access to #information.”@deepthiw
“My last article couldn't be possible without the platform @deepdyve that makes journal papers cheaper.”@JoseServera