Suggested Response - Q5

**You are about to purchase malt. The CoA shows that the following parameters are out of the normal specification range of analysis (indicated within brackets):

(a) β-Glucan 250 mg/L (< 200 mg/L)

(b) Viscosity 1.7 cP @ 20˚C (< 1.65 cP @ 20˚C)

(c) HWE 70% (> 80%)

Explain what could have gone wrong during the malting process, in detail.

Response:

When considered together, the three parameters indicate an under-modified malt.

Steeping is intrinsic to achieving the ideal moisture of 43-46%. Germination starts at 30% moisture. The barley continues growing in the germination vessel. The modification must be even and complete to achieve the malt quality specifications. The following can contribute to under modified malt:

  • Dead, or dying, barley used for steeping.
    • Storing pre-germinated barley.
    • Mould or fungi growth during storage.
    • Insect infestation in the silo.
  • Dormant barley
  • Inadequate water uptake during steeping.
    • Water temperature too low.
    • Water stands too short.
    • Barley is water sensitive.
    • Barley has drowned.
  • Process delays in steeping and germination, without aeration and turning, resulting in high CO2 and temperature.
  • Early transfer to kiln from the germination vessel.
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