Impact of storage environment on respiration, dry matter losses and fumonisin B1 contamination of stored paddy and brown rice

• Published in: World Mycotoxin Journal
• Main Authors: Castaño, S. Martín, Medina, A., Magan, N.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Brill 2017
• Subjects: DML
• Online Access: http://dx.doi.org/10.3920/wmj2017.2237; https://brill.com/view/journals/wmj/10/4/article-p319_3.xml; https://brill.com/downloadpdf/journals/wmj/10/4/article-p319_3.xml

The objective of this study was to compare the effect of different storage moisture conditions (0.90 and 0.95 water activity, a w ) and temperatures (25, 30 °C) on (1) respiration rates (CO 2 R), (2) dry matter loss (DML) of paddy and brown rice, (3) inoculation of both rice types with Fusarium verticillioides under these storage conditions on R, DML, and (4) effects on fumonisin B 1 (FB 1 ) contamination of these rice types. There was an increase in temporal CO 2 production with wetter and warmer conditions in naturally contaminated rice. Higher R and consequently, percentage (%) DML were generally observed for brown rice (up to 21%) while in paddy rice this was only up to 3.5% DML. The FB 1 production in paddy rice was low and similar in all treatments regardless of a w × temperature conditions. In the dehusked brown rice there were higher levels of contamination with FB 1, with a maximum at 0.95 a w and 25 °C. A significant correlation between %DMLs and FB 1 contamination was obtained (R=0.7454, P <0.01). These results suggest that monitoring of CO 2 may provide an early indication of fungal activity in moist rice and help in evaluating the relative risk of spoilage and potential for mycotoxin contamination.