- Ellen DParticipantJanuary 1, 2015 at 8:29 pmPost count: 4
There was a study done recently in Hawaii (where diabetes is a major health issue and much rice is eaten) analyzing the levels of resistant starch in jasmine, long grain, medium grain and short grain rice cooked by various methods.
This study showed that jasmine rice had consistently higher levels of RS than either short or medium grain rice when freshly cooked. The only circumstance under which jasmine rice was lower in RS than the other 3 varieties was when it was cooked in a rice cooker and then refrigerated. When cooked in a rice cooker, it has more than twice as much resistant starch than short grain rice.
Here is the study:
This seems to bring into question the assignment of 0 FP to jasmine rice. Does that value apply when some cooking method other than the 3 tested about are used? I’ve been using a rice cooker for 30 years, and would never try to cook rice on the stove.Norm RobillardKeymasterJanuary 2, 2015 at 8:31 pmPost count: 441
Thanks for bringing this study to my attention. There’s so much info on this subject, it’s difficult to fully cover it here, but here are a few thoughts.
The finding that jasmine rice (and short grain rice) has little resistant starch, even after refrigeration is consistent with the assignment of a high GI and low FP for this rice variety. Recall in the book, we warn that refrigeration or starches can increase the amount of RS. Better to eat it fresh.
It’s a little hard to assess their finding of relatively low levels of RS in the long grain rice they tested as I don’t know the details of the rice variety and brand they used. It would have been interesting if they included the high FP varieties (for instance, basmati and Uncle Bens) that I list in Fast Tract Digestion. I would like to see what GIs values they would get with those rices and would expect them to be low as previously reported.
As for the finding that freshly cooked jasmine rice has more RS than medium or short grain rice, the reason likely lies in how RS is analyzed in the test tube by invitro enzyme-based methods such as the preferred method, AOAC 2002.02. The test involves extensive enzymatic digestion of the starch for many hours. Perhaps that is the reason even high amylose-starches yield relatively low levels of RS by this assay. But many studies have linked high amylose starches (specific varieties of corn, potato, rice, etc) to low GIs and low amylose starches (including both short grain and jasmine rices) to high GIs. Based on this body of work, I feel pretty confident calculating high and low FP values from these low and high GIs.
In other words, amylose, the more resistant starch, can still be digested, just not as easily or quickly as amylopectin starch. That’s the reason in my opinion that the GIs are lower (and FPs higher) for high amylose starches. Because they don’t digest as fast thus creating fermentation potential (the reason I call it “potential” is because it’s not an absolute) that can overfeed gut bacteria, particularly in the small intestine.Ellen DParticipantJanuary 3, 2015 at 4:27 pmPost count: 4
Thank you Norm – I have a couple more questions about rice: the FTD menus in the book all call for very small servings of rice. I know my rice cooker wouldn’t do the job with such a small quantity, so is there any way to reheat refrigerated rice that minimizes the increase in FP? I sometimes use leftover rice to make okayu for breakfast: would cooking this way, using about twice as much water as rice, increase or decrease the FP of refrigerated rice? Also all the menus in FTD seem to call for sticky rice – it’s harder for me to find than jasmine, but is it better in some way than jasmine? (I got the impression from the FP tables that jasmine has the lowest FP of any rice variety.JaemeParticipantJanuary 3, 2015 at 5:58 pmPost count: 348
Hi Ellen D – I used Jasmine rice in place of sticky, because of the lower FP and easier to find where I live. In the book, Norm suggests reheating leftover rice to steaming to reconvert some of the resistant starch that forms when it cools. I made normal batches of rice, measured out single 1/2 cup servings (using digital scale) and froze each serving right away in snack size ziploc bags. Easy to reheat quickly in microwave for quicker meal prep, and did not give me any digestive problems. I figured if the Jasmine rice gained a few FP points as leftovers, it would still only equal the FP of fresh cooked sticky rice.Norm RobillardKeymasterJanuary 3, 2015 at 7:45 pmPost count: 441
Hi Ellen, I agree with Jaeme’s comment. There is no reason for using more Asian sticky rice in the recipes. Jasmine is just as good, with a slightly lower FP. The small serving sizes are important – at least until digestion improves. Refrigeration and freezing are great for leftovers, but will result in small increases in resistant starch. Heating up the leftovers well, without overheating the rice will help limit RS. Fried rice will also have more RS than steamed.JaemeParticipantJanuary 4, 2015 at 4:05 amPost count: 348
Hi Norm – my comment seems to have disappeared from this thread. Should I repost?
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