Development of biopolymer coated calcium fortified rice using spraying and soaking methods

•Developed calcium fortified rice premix using biopolymer coating.•Spraying method resulted higher whiteness index and harder rice premix.•Highest calcium retention after washing was in zein coated rice premix.•Acceptability of cooked calcium fortified rice was unaffected due to biopolymer coating.

Calcium fortified rice premix was prepared adding calcium chloride as fortificant by soaking and spraying method followed by biopolymer coating namely hydroxypropyl methyl cellulose (HPMC), methyl cellulose (MC), combination of HPMC and MC and zein. Spraying method resulted in relatively higher whiteness index and hard texture of calcium fortified rice premix than soaking method. Calcium content in calcium fortified rice premix samples, prepared using soaking and spraying methods ranged from 9.93 to 22.39 and 11.84 to 25.39 mg/g, respectively. Biopolymer coating of calcium fortified rice premix reduced the washing losses of calcium. Retention of calcium after two washing in distilled water was highest in zein coated (at 9% level) calcium fortified rice premix followed by combination of HPMC and MC at 2% level. Overall acceptability scores for different cooked samples of calcium fortified rice ranged from 7.66 to 8.14 as compared to 8.07 for unfortified rice. Though insignificant but higher overall acceptability scores for HPMC and MC (at 2% level) coated cooked fortified rice indicated the scope for development of calcium fortified rice premix by spraying calcium solution containing 120 mg calcium per mL, 150 min tempering time, followed by HPMC and MC (at 2% level) coating and drying.