Canadian Grain Commission
Symbol of the Government of Canada

Prediction of germination energy of malting barley during long-time storage



Recommended safe storage time for barley samples with various degrees of pre-germination

In order to more accurately predict the storage life of samples with various degrees of pre-germination, during the second year of this investigation long -term storage studies were also conducted. Barley samples with various degrees of pre-germination, as determined by the RVA test, were stored in four different environments:

  1. Temperature ≥ 25°C; relative humidity ≥ 60%
  2. Temperature 20-23°C; relative humidity ≤ 40%
  3. Temperature ~5°C; relative humidity 50-60%
  4. Outdoor, variable conditions: samples were placed in the outdoor conditions in January 2004 and stored until January 2005.

The safe storage life of samples (retention of GE ≥ 95%) was dependent on the following factors:

  • The degree of pre-germination in samples
  • Storage conditions: temperature and relative humidity
  • The initial moisture content of barley samples

In order to predict the storage life of barley samples more accurately, all factors have to be considered. Based on the storage studies conducted during the second year of this investigation, the following safe storage time is recommended for barley samples with various degrees of pre-germination:

Safe storage time
Storage conditions Safe storage time
RVA FV 0 - 50 (RVU1) RVA FV 50 - 90 (RVU1) RVA FV 90 - 135 (RVU1) RVA FV ≥ 135 (RVU1)
T ≥ 25°C RH2 ≥ 60% 1 - 4 weeks 1 - 8 weeks 4 - 24 weeks 16 - 41 (+) weeks (+) samples tested for the last time at 41 weeks exhibited GE ≥ 95
T 20 - 23°C RH2 ≤ 40% 2 - 24 weeks 32 - 42 (+) weeks 42 (+) - 50 (+) weeks 42 (+) - 50 (+) weeks
T ~ 5°C RH2 50 - 60% 8 - 42 weeks 32 - 42 (+) weeks > 42 (+) weeks 41 (+) - 50 (+) weeks
Outdoor storage Starting date: Jan 2004 Samples lost GE in May-June 2004 Samples lost GE in June -August 2004 Samples lost GE in June-November 2004. However, one sample with a low moisture content retained GE until January 2005 Samples were tested for the last time in November 2004 - all samples still exhibited good GE.

1 Rapid Visco Units

2 Relative Humidity

Note: It is possible that a large volume of barley stored in any of the above conditions will retain/lose germination energy in a slightly different time because the temperature and/or moisture of grain inside a large bin will not change at the same rate as for a smaller sample.