Resistant starch and modified starch refer to two distinct types of material. Modified starch means that the native starch has been chemically or enzymically altered, and typically includes starch derivatives. For starters, just see the Wikipedia entry for modified starch and you'll see some of the various chemical derivatives that can fall under that definition.  On the other hand, resistant starch usually refers to a type of starch structure that is resistant to digestion in the GI tract of humans and other animals.  Quite often, these are partially degraded by enzymes, or derived from plant sources that make a highly branched amylopectin structure that is more resistant to digestion by animals.

Resistant starch and modified starch refer to two distinct types of material. Modified starch means that the native starch has been chemically or enzymically altered, and typically includes starch derivatives. For starters, just see the Wikipedia entry for modified starch and you'll see some of the various chemical derivatives that can fall under that definition.  On the other hand, resistant starch usually refers to a type of starch structure that is resistant to digestion in the GI tract of humans and other animals.  Quite often, these are partially degraded by enzymes, or derived from plant sources that make a highly branched amylopectin structure that is more resistant to digestion by animals.

Thank you Dr. Greg Cote. This was very helpful.

Regards

Hello Shefali Bharadwaj..

Starches are inherently unsuitable for most applications and, therefore, must be modified chemically /physically and/or enzymatically to enhance their positive attributes and/or to minimize their defects.

The term “resistant starch" (RS) describes a small fraction of starch that is resistant to hydrolysis by exhaustive -amylase and pullulanase treatment in-vitro. In other ways, RS is the starch not hydrolyzed after 120 min. of incubation.  RS is also defined as that fraction of dietary starch, which escapes digestion in the small intestine.

RS appears to be highly resistant to mammalian enzyme and may be classified as a component of fiber on the basis of the recent definitions of dietary fiber given by AACC (2000) and NAS (2002). While part of the RS may consist of low-molecular-weight dextrins, the bulk consists of polymers, of which retrograded amylose

often forms the major fraction.

RS is obviously nutritionally more similar to  non‐starch polysaccharides  than to digestible starch. There is ample justification that RS behaves physiologically like fiber. RS assays as insoluble fiber, but has the physiological benefits of soluble fiber.

Additionally, RS exhibits a level of slow digestibility and can be used as a vehicle for the slow release of glucose.....

Thank you Dr. Naik!

That was really helpful.

I had another doubt about RS and the quantities it can be added in for product development. As FSSAI has mentioned limits for modified starches and there is no mention on RS levels. I was wondering if RS has to be treated as a modified starch in this case.

Resistant

Starch—

A Review

http://onlinelibrary.wiley.com/doi/10.1111/j.1541-4337.2006.tb00076.x/pdf

"A modified food starch undergoes one or more chemical or physical modifications, which allow it to function properly under high heat and/or shear frequently encountered during food processing. The word 'modified' thus refers to the chemical structure of the starch molecule and has nothing to do with genetically modified plants or foods."

"Modified starch" refers to chemical modifications to starch structures, while "resistant starch" refers to the digestion profile (resistant starch resists digestion). You could build a 2 x 2 box with the two traits because you can have both modified digestible starches and modified resistant starch as well as natural (unmodified) digestible starch and natural resistant starch.

I have been working with natural resistant starch for 15+ years and built www.ResistantStarchResearch.com to explain the mechanisms and benefits. There are currently 154 published human clinical studies on natural (unmodified) resistant starches from green bananas, potatoes, high amylose corn, peas, tapioca, etc. These studies show that this type of starch feeds the microbiota (bacteria) in the large intestine in a process called fermentation which produces a lot of the beneficial short chain fatty acid called butyrate (more than any other types of dietary fiber), improve regularity, stop diarrhea, heal leaky guts and intestinal ulcereations, improve insulin sensitivity, improve fat metabolism and reduce toxins important for people with kidney disease. More than 300 animal studies have been published exploring an even wider range of health benefits.

Resistant starch has these amazing benefits because the fermentation by the bacteria changes the expression of >200 genes in the large intestine, which then triggers changes in genes all over the body. Last year, the FDA approved a health claim that "limited evidence demonstrates that resistant starch from high amylose corn reduces the risk of type 2 diabetes", so even the regulators are becoming aware of these important health benefits.

I know of about 10 clinical studies on chemically modified resistant wheat starch, which shows less butyrate, and different changes in the microbiota compared to natural resistant starch. Most of the studies show that it is different than natural resistant starch, but we really do not know much about chemically modified resistant starch's health effects. It is used in the food industry as a dietary fiber in products such as high fiber bread, and is labeled as "modified wheat starch" or "resistant wheat starch."

The health impact of digestible chemically modified starches is mostly believed to be neutral. There are a lot of modified starches in our foods (especially processed foods), but generally have data that they're safe to consume.

Natural resistant starch is definitely something that you want in your diet - it keeps your gut working well and healthy, which in turn keeps you working well and healthy. Cannot say the same about other types of modified starches.

Thank you Sir.

Hi Shefali,

I agree to all comments above, I just wanna mention in addition to these comments, there is a type of RS that is actually modified, which is named RS4 (type four). RS4 is achieved by chemical reactions in lab such as esterification. This made starch more resistance to Amylase and diastase effects in GI system.

You can also take a look at my article:

Article Resistant starch in food industry: A changing outlook for co...

Cheers

Resistant starch and modified starch refer to two distinct types of material. Modified starch means that the native starch has been chemically or enzymically altered, and typically includes starch derivatives. For starters, just see the Wikipedia entry for modified starch and you'll see some of the various chemical derivatives that can fall under that definition.  On the other hand, resistant starch usually refers to a type of starch structure that is resistant to digestion in the GI tract of humans and other animals.  Quite often, these are partially degraded by enzymes, or derived from plant sources that make a highly branched amylopectin structure that is more resistant to digestion by animals.