Ricemilks made from pigmented and aromatic rice varieties: Sensory analysis and physiochemical properties

Abstract

Along with dairy allergic/intolerant and vegetarian/vegan individuals, flexitarian consumers contribute to the market for plant-based milk alternatives. Niche pigmented (purple and red) and/or aromatic (aromatic brown and white) rice varieties were used to formulate ricemilks, which were compared to a product made from commercial nonaromatic white rice. Descriptive sensory analysis (9 trained panelists) and affective sensory testing (161 consumers) were used to explore perceptions of ricemilks. Additional sample differences were characterized by instrumental color, viscosity, 2-acetyl-1-pyrroline (2-AP), starch quality, total phenolic content (TPC), oxygen radical absorbance capacity (ORAC), and proximate analyses. Compared to nonaromatic white ricemilk, increased bioactive and antioxidant potential was exhibited for pigmented varieties (TPC ranging 56.6-64.5 µg/mL; ORAC ranging 628-753 µM Trolox equivalents). However, the pigments also resulted in decreased acceptability of product color. For red ricemilk, this was overcome after tasting, resulting in the highest grouping of overall liking scores along with aromatic brown and aromatic white ricemilks (5.6-5.7 on a 9-point hedonic scale)-all associated with a desirable "popcorn" aromatic from 2-AP. Highest purchase intent was found for aromatic brown ricemilk (47% overall and 69% among regular dairy and nondairy milk consumers) which was associated with the "dairy" aromatic. Consumers also favored colors and mouthfeel more reminiscent of dairy milk. Ricemilks made from niche pigmented and/or aromatic rices provided unique flavors and outperformed nonaromatic white ricemilk in overall acceptability. Ricemilks made from aromatic whole grain varieties can offer a new health-promoting functional beverage option to consumers, and a new use of niche rice varieties.

Keywords: aromatic rice; phenolics; pigmented rice; ricemilk; sensory analysis.