【Megazyme】Resistant Starch Assay Kit (Rapid) (K-RAPRS)

The Megazyme Difference

Based on the groundbreaking RINTDF method (AOAC 2017.16) for Total Dietary Fiber, Megazyme’s new Resistant Starch Assay Kit (Rapid) (K-RAPRS) introduces a new procedure that generates the most accurate and physiologically-relevant in vitro results available for resistant starch.

Recent studies on the hydrolysis of “newer” resistant starch materials - such as phosphate crosslinked starch (RS₄) - indicate that to obtain meaningful physiologically relevant values for RS, the time of incubation with PAA/AMG should be in line with the time of residence of food in the small intestine. This improved rapid method therefore reduces the length of the enzyme incubation step from 16 h to just 4 h, allowing laboratories to obtain results that more accurately simulate in vivo studies and to reduce the overall assay time.

Resistant Starch and Total Dietary Fiber

Resistant Starch is a component of Total Dietary Fiber according to the 2009 Codex definition, accepted internationally.

The Rapid method used in our new kit is also employed in AOAC Method 2017.16 for the measurement of Total Dietary Fiber as defined by Codex.

• AOAC Method 2017.16 is available in the Rapid Integrated Total Dietary Fiber kit (K-RINTDF).

• For laboratories that are still using pre-2009 analytical methods, Megazyme continues to offer the K-TDFR kit for Total Dietary Fiber, which does not accurately measure resistant starch.

Results Obtained from Resistant Starch (Rapid) vs AOAC Method 2002.02

Results obtained using the new Resistant Starch (Rapid) procedure correlate closely with those of AOAC method 2002.02. For a number of samples, results from the Rapid method indicate that there may be significant under-reporting of Resistant Starch under the established method as demonstrated in the table below.

Resistant Starch and Starch Content

The Resistant Starch Assay Kit (Rapid) (K-RAPRS) method describes procedures which measure Resistant Starch, Total Digestible Starch, and subsequently Total Starch.

• Digestible Starch (including Rapidly Digested Starch, Slowly Digested Starch and Total Digestible Starch) may be analysed in greater detail using Megazyme’s Digestible and Resistant Starch Assay Kit (K-DSTRS).

• The Available Carbohydrates Assay Kit (K-AVCHO) determines available carbohydrates incorporating total digestible starch content.

• For rapid measurement of Total Starch only, our Total Starch Assay Kit K-TSTA (AOAC Method 996.11) remains the most suitable procedure. This method has been the international standard for over 20 years and has recently been updated for more accurate measurement of starch in animal feeds and pet foods.