Two hundred grams of rice was thoroughly coated with the beetroot juice by spraying the juice over the rice kernels and trembling in a rotating mixing bowl (0.67 s 1) for 2 min. The
beetroot juice was added to the rice kernels at various amounts from 4 to 6 g/100 g rice. It was homogeneously coated on the rice kernels. The juice-rice mixture was then immediately placed in a 3- L hermetically sealed chamber. The vacuum inside the chamber was rapidly established to 74.66 kPa in 30 s, held for 2 min, and released to the atmospheric pressure within 1 min. The rice kernel products were taken out from the chamber and packed in a tightly closed glass jar prior to further use.