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

Authors: Ardoin, Ryan; Chaffee, Olivia; Lea, Jeanne; SOOKRAJ, ALYSZA - Oak Ridge Institute For Science And Education (ORISE); Boue, Stephen; Smith, Brennan; Dupre, Rebecca; Olson, Douglas; BROUSSARD, WILLIAM - Oak Ridge Institute For Science And Education (ORISE); Priddy, Daniel

Submitted to: Journal of Food Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/20/2024
Publication Date: 12/14/2024
Citation: Ardoin, R., Chaffee, O., Lea, J., Sookraj, A., Boue, S., Smith, B., Dupre, R., Olson, D. W., Broussard, W., Priddy, D., Ricemilks made from pigmented and aromatic rice varieties: Sensory analysis and physiochemical properties. Journal of Food Science. 89(12):8770-8783. https://doi.org/10.1111/1750-3841.17592.
DOI: https://doi.org/10.1111/1750-3841.17592

Interpretive Summary: Red and purple rices get their distinctive color from pigments which can provide health-benefits such as anti-oxidant effects in the body. Aromatic rices, including some pigmented varieties, have a desirable popcorn-like aroma. With a growing market for plant-based milk-alternatives, this research compared ricemilks made from pigmented and aromatic rice varieties to a product made from a typical non-aromatic white rice. Antioxidant activity of red, purple, and brown ricemilks was confirmed to be greater that of white ricemilks. Based on sensory analysis, red and purple ricemilks had a unique berry flavor, but their unusual color was rated negatively by consumers. In general, consumers preferred ricemilks with a color, consistency, and flavor more similar to cow's milk. However, all aromatic ricemilks were more acceptable than the non-aromatic white ricemilk. This research demonstrated a new use of niche pigmented and aromatic rice varieties, which can deliver health-promoting compounds and enhanced sensory properties.

Technical 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 non-aromatic 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-1pyrroline (2-AP), starch quality, total phenolic content (TPC), oxygen radical absorbance capacity (ORAC), and proximate analyses. Compared to non-aromatic white ricemilk, increased bioactive and antioxidant potential was exhibited for pigmented varieties (TPC ranging 56.6-64.5 µg/ml; ORAC ranging 627-753 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 non-diary 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 non-aromatic 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.