Tsu-om or Du-om is Roast Rice Crunch. In Tagalog, and some other Filipino dialects, this is called Pinipig. The Igorots do not have the sole ownership of this food idea, but they do have a very distinctive style. This is only applicable if you are /will currently harvest rice by hand. This is how Igorots make it, and no alternatives are offered that can equal this.
Young rice yet to be pounded.
Mortar and Pestle
Big Frying Pan
Winnower(A wide flat basket, or a wide flat basin can be used to those who know how).
Selecting the right riceAfter harvesting the rice in the rice field, Select the not so mature rice that is left immediately afterwards (There always is some left). This type should be dense enough, yet should have a milky liquid in the middle. To test, remove the husk from one grain, and split the rice grain into two, or simply crush it with your fingers. There should still be some liquid left. Normally, one rice grain tested is enough for you to gauge what rice to gather is best for Tsu-om, since you would(of course) notice the color of the stalk, the husk, and the wat it stands up (The stalk won't be too bent, since it is not yet too heavy for the stalk). Gather at least four bundles ("fetek", or "botok" or "hinbotok") or if you want a definite measurement, something that would approximate a halk kilo of rice after being dehusked. (Around 1 and a half kilo of rice, including husks and stalks/panicles).
The period of time from the time it is gathered to the time you start preparing it should be within not exceed six hours, if you wish to achieve the best taste possible. If it should exceed, wet the rice every 15 minutes. Using a mortar and a pestle, separate the rice from the stalks/panicles. Put the rice into the Big Frying Pan (We use a Vat, which Filipinos call either "Silyasi" or "Talyasi"). Start a fire, and the fire should be high enough. Stir, using the wooden ladle, so that the heat would be even. (During the roasting of the rice, you'd love the smell that comes out.) The rice Husks before roasting are either a green gold color or green color. As it is being roasted, it changes to a dry brown color. You can test it manually if the raosting is finished. Pick a grain. If you remove the husk, and the kernel is too soft, and the liquid has not solidified yet, it is not yet finished. If the kernel is a soft, and when you squeeze it, it is sticky, it is not yet finished. Do not make a mistake by removing the rice at this point! You will have a hard time removing the chaff/husks. The kernel should be solid enough and is not sticky to indicate that it can now be removed from the roasting. When you think it is done, remove it from the Pan/vat immediately, Since the still undissipated heat will keep roasting the grains. Now, using the mortar and pestle, pound it to remove the husks, and using a winnower, remove/separate the chaff from the grain. The result is now ready to eat. If the grains are still colored green, you got it right the first time, from the harvesting to the roasting. Most kids who love this would include adding a little brown sugar. The result is just perfect. The grains are still soft and chewable. They should be eaten within one hour.
Most Commercial pinipig, and other lowland pinipig that I have tasted do not approximate what we used to make. Commercial pinipig are the worst... They are made from either mature grains, or non-fresh grains. Non-fresh grains in the sense that the makers would get grains still with husks and boil them, till the kernel inside gets soft. Then this are roasted afterwards, before they are pounded. They simply taste like boiled rice. Lowland Pinipig (I've tasted those from San Fernando, from Pangasinan, from Nueva Ecija, From Tugegarao, from La Union, and the Ilocos regions, and the taste is quite the same: not as good as the Igorot "Tsu-om". Why .. My opinion, backed by several occasions where I was able to observe the way rice is harvested, is that the rice picked for Pinipig was not picked from pure, immature grains. While lowland people either use sickles or machines to harvest rice, The Igorots harvest rice as it had been during the olden times, people pick the grains by hand, and they pick only what is mature enough for harvesting. Thus, they also pick the rice for Tsu-om by hand, enabling them to select only what should be made for Tsu-om. If, on occasion, you have drop by a rice growing town in the Cordilleras, and it is rice harvest time, check out the people who are currently harvesting rice. Perhaps they'll be making Tsu-om?