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2-acetyl-1-pyrroline (2AP) is recognized as the key aromatic compound in fragrant rice, however, the effect of light quality on rice aroma is not fully understood. In this study, two fragrant rice varieties (Xiangyaxiangzhan and Yuxiangyouzhan) were grown under four light quality treatments (CK: natural light, L1: red light, L2: blue light and L3: combined light). Results depicted that L1, L2 and L3 treatments enhanced the grain yield by 14.24–35.36%, compared to CK whilst L2 and L3 treatments reduced the 2AP content in grains by 17.18–28.68%. Moreover, L1, L2 and L3 treatments enhanced the grain yield owing to improved filled grain percentage and regulation in antioxidant enzyme activities. On the other hand, L2 and L3 reduced the 2AP content in grains by decreasing pyrroline-5-carboxylic acid content and modulating proline and γ-aminobutyric acid content. Overall, this study revealed that light quality substantially affects the grain yield and quality characters of fragrant rice. [ABSTRACT FROM AUTHOR]

When using predictive models to assess the risk posed by foodborne pathogens, certain strains exhibit resistance at low temperatures, which may affect the assessment result. To understand the influence of strain heterogeneity on growth dynamics, two Staphylococcus aureus strains, including comparatively low temperature tolerant BB-11 and sensitive BA-26, were inoculated into glutinous rice dough at temperatures ranging from 10 to 37 °C. The primary Gompertz model fit showed an obvious difference in the maximum specific growth (μ max) and duration of the lag phase (λ) values at 10 °C (0.071/h and 28 h for BB-11 and 0.049/h and 34 h for BA-26, respectively). When Huang and Ratkowsky models were compared as secondary models, a log-linear relationship was demonstrated between μ max and λ for both models. Ratkowsky's model fit was more accurate with a high R 2 of 0.95. The predicted minimum growth temperatures were 4.8 °C and 6.3 °C for BB-11 and BA-26, respectively. The time for achieving a 4-log increase (t 4.0) was 96 h for BB-11 at 10 °C, but only 2.4 log CFU/g increase was determined in BA-26 at 144 h. This study suggests that cold-tolerant strains should be considered when a predictive model is used for risk assessment of foodborne pathogens. • Cold tolerant and sensitive S. aureus exhibited different growth curves in glutinous rice dough. • The two strains showed an obvious difference in μ max and λ values at 10 °C. • Ratkowsky's model fit was more accurate when used as secondary model. • Cold-tolerant strains should be well considered when a predictive model is constructed. [ABSTRACT FROM AUTHOR]