Texture differences of cooked quinoa were studied among 13 different varieties. Correlations between the texture parameters and seed composition, seed characteristics, cooking quality, flour pasting properties, and flour thermal properties were determined. The results showed that texture of cooked quinoa was significantly differed among varieties. 'Black,' 'Cahuil,' and 'Red Commercial' yielded harder texture, while '49ALC,' '1ESP,' and 'Col.#6197' showed softer texture. '49ALC,' '1ESP,' 'Col.#6197,' and 'QQ63' were more adhesive, while other varieties were not sticky. The texture profile correlated to physical--chemical properties in different ways. Protein content was positively correlated with all the texture profile analysis (TPA) parameters. Seed hardness was positively correlated with TPA hardness, gumminess, and chewiness at P ≤ 0.09. Seed density was negatively correlated with TPA hardness, cohesiveness, gumminess, and chewiness, whereas seed coat proportion was positively correlated with these TPA parameters. Increased cooking time of quinoa was correlated with increased hardness, cohesiveness, gumminess, and chewiness. The water uptake ratio was inversely related to TPA hardness, gumminess, and chewiness. Rapid Visco Analyzer peak viscosity was negatively correlated with the hardness, gumminess, and chewiness (P < 0.07); breakdown was also negatively correlated with those TPA parameters (P < 0.09); final viscosity and setback were negatively correlated with the hardness, cohesiveness, gumminess, and chewiness (P < 0.05); setback was correlated with the adhesiveness as well (r = -0.63, P = 0.02). Onset gelatinization temperature (To ) was significantly positively correlated with all the texture profile parameters, and peak temperature (Tp ) was moderately correlated with cohesiveness, whereas neither conclusion temperature (Tc ) nor enthalpy correlated with the texture of cooked quinoa.

Quinoa is becoming increasingly popular, with an expanding number of commercially available varieties. To compare the sensory properties of these quinoa varieties, a common sensory lexicon needs to be developed. Thus, the objective of this study was to develop a lexicon of cooked quinoa and examine consumer acceptance of diverse varieties. A trained panel (n = 9) developed aroma, taste/flavor, texture, and color descriptors to describe the sensory properties of 21 quinoa varieties. In addition, texture of the cooked quinoa was determined using a texture analyzer. Results indicated that the developed lexicon could distinguish among these quinoa varieties, showing significant differences in aromas, taste/flavors, and texture attributes. Specifically, quinoa variety effects were observed for the aromas of caramel, nutty, buttery, grassy, earthy, and woody; taste/flavor of sweet, bitter, grain-like, nutty, earthy, and toasty; and firm, cohesive, pasty, adhesive, crunchy, chewy, astringent, and moist textures. Three varieties, "QQ74," "Linares," and "CO407D," exhibited an adhesive texture that has not been described in other commercialized quinoa. Subsequent consumer evaluation (n = 100) on 6 selected samples found that the "Commercial Red" sample was the most accepted overall whereas the least accepted was the field variety "QQ74." For all consumers, overall acceptance of quinoa was driven by higher intensities of grassy aroma, and firm and crunchy texture. Segmentation of the consumers into 4 groups was explored and showed that consumers varied in their acceptance of specific attributes, particularly texture. From the present study, the quinoa lexicon and key drivers of consumer acceptance can be utilized in the industry to evaluate quinoa varieties, product quality and processing procedures.

The research determined starch characteristics among a diverse set of pure quinoa varieties and commercial samples, and identified the relationships between starch properties and cooked quinoa texture. The results can help breeders and food manufacturers to understand better the relationships among quinoa starch characteristics, cooked quinoa texture, and the best use of different cultivars.

Quinoa (Chenopodium quinoa Willd.) is an Andean crop with an edible seed that both contains high protein content and provides high quality protein with a balanced amino acid profile in embryonic tissues. Quinoa is a halophyte adapted to harsh environments with highly saline soil. In this study, four quinoa varieties were grown under six salinity treatments and two levels of fertilization, and then evaluated for quinoa seed quality characteristics, including protein content, seed hardness, and seed density. Concentrations of 8, 16, and 32 dS m-1 of NaCl and Na2SO4, were applied to the soil medium across low (1 g N, 0.29 g P, 0.29 g K per pot) and high (3 g N, 0.85 g P, 0.86 g K per pot) fertilizer treatments. Seed protein content differed across soil salinity treatments, varieties, and fertilization levels. Protein content of quinoa grown under salinized soil ranged from 13.0 to 16.7%, comparable to that from non-saline conditions. NaCl and Na2SO4 exhibited different impacts on protein content. Whereas the different concentrations of NaCl did not show differential effects on protein content, the seed from 32 dS m-1 Na2SO4 contained the highest protein content. Seed hardness differed among varieties, and was moderately influenced by salinity level (P = 0.09). Seed density was affected significantly by variety and Na2SO4 concentration, but was unaffected by NaCl concentration. The samples from 8 dS m-1 Na2SO4 soil had lower density (0.66 g/cm3) than those from 16 dS m-1 and 32 dS m-1 Na2SO4, 0.74 and 0.72g/cm3, respectively. This paper identifies changes in critical seed quality traits of quinoa as influenced by soil salinity and fertility, and offers insights into variety response and choice across different abiotic stresses in the field environment.

No abstract