The impact of pH on enzymes.
During the saccharification process, pH often significantly affects the activities of various enzymes. The repeated high pH of the water causes the pH of the mash to rise, reducing the effectiveness of the enzymes.
For α-pepsin and some exopeptidases, in the pH range of 5.2 to 5.3, the lower the pH of the mash, the better the enzyme’s effectiveness.
When the pH exceeds the ideal pH for the “enzyme,” the α-pepsin protease is inhibited, and the saccharification time also increases.
The effectiveness of β-glucanase is minimized, resulting in unscientific dissolution of β-glucan and increased viscosity of beer malt.
If endopeptidase is damaged, a certain proportion of soluble nitrogen is produced, converting healthy proteins into carbohydrates, which slows down the whole process.
When the pH value is as high as 6.0 to 6.2, the activity of aminopeptidase and dipeptidase is generally weakened, and phosphatase is also affected, resulting in inhibition.
Only a significant amount of unnatural ammonium sulfate can be liquefied from natural materials, but this proportion of unnatural ammonium sulfate rapidly reacts exothermically with bicarbonate, causing insoluble polyphosphate precipitation and reducing the water content of phosphate in beer malt, thus minimizing its buffering capacity.
Impact on yield.
To mitigate the enzyme’s impact, the increased viscosity of beer malt makes filtration difficult and results in insufficient distiller’s grains, leading to a 2-3% decrease in saccharification yield.
Impact on beer malt characteristics.
When the pH value of the mash, main beer malt, and distiller’s grains is high, certain undesirable substances in the husk enter the beer malt, increasing wine saturation and resulting in a rough taste with bitterness. Some healthy proteins that need to dissolve at specific pH requirements do not dissolve well at higher pH, which can cause cloudiness and imbalance in the wine.
Impact on hop bitterness utilization rate.
The higher the pH value of the beer malt, the higher the utilization rate of hop bitterness. This leads to incorporation of a large amount of humulus salt, which produces a dry and unpleasant bitterness in the beer. When the tap water is acidic, the amount of hops should be reduced to ensure moderate bitterness and water content, but the resulting wine may still have weak bitterness and acidity (palatability).