Modelling respiration rate of soybean seeds (Glycine max (L.)) in hermetic storage.

GASTÓN, A.; OCHANDIO, D.; GASTÓN, A.; ARIAS BARRETO, A.; ABALONE, R.; BARTOSIK, R.; OCHANDIO, D.; YOMMI, A.; ARIAS BARRETO, A.; ABALONE, R.; BARTOSIK, R.; YOMMI, A.

JOURNAL OF STORED PRODUCTS RESEARCH

PERGAMON-ELSEVIER SCIENCE LTD

Año: 2017 p. 36 - 45

0022-474X

The dynamic of oxygen (O2) andcarbon dioxide (CO2) concentration was characterized in soybean (Glycine max (L.)) samples hermetically stored in glass jars at 15, 25 and 35C and 13, 15 and 17% moisture content (m.c., wet base). Two correlations were used for smoothing gasconcentration in time: linear and exponential. Then, the respiration rate ateach temperature and m.c. combination was calculated as storage time progressedand oxygen was consumed and two predictive models for respiration were proposed:Model I (temperature and m.c. dependent) and Model II (temperature, m.c. and oxygendependent). It was observed that respiration rate increased with storage m.c.and temperature. However, respiration rate was not mainly affected by O2 until a critical concentration limit of about 2% was reached. Respiration rates werefrom 0.341 to 22.684 mg O2/(kgDM d) and from 0.130 to 20.272 mgCO2 /(kgDM d)for a range of storage condition of 13e17% m.c. and15e35C temperature. The respiration rate of soybean seeds obtained in this study resulted significantly lower than the ratesreported in the literature for other grains at similar temperature and aw (water activity) storage condition. For hermetic storage simulations in which O2concentrationis not expected to drop below 2%, the simplest model (Model I) could be used,but if the O2 concentration of the hermetic system is expected to be depleted, ModelI would under estimate the time at which O2 is consumed, and thus a model with O2 dependency is recommended instead (Model II).