brew.utilities.sugar

sugar.sg_to_gu(sg)

Specific Gravity to Gravity Units

Parameters:sg (float) – Specific Gravity
Returns:Gravity Units
Return type:float
sugar.gu_to_sg(gu)

Gravity Units to Specific Gravity

Parameters:gu (float) – Gravity Units
Returns:Specific Gravity
Return type:float
sugar.plato_to_sg(deg_plato)

Degrees Plato to Specific Gravity

Parameters:deg_plato (float) – Degrees Plato
Returns:Specific Gravity
Return type:float

The simple formula for S.G. is:

\(\text{SG} = 1 + 0.004 \times \text{Plato}\)

The more precise calculation of SG is:

\(\text{SG} = \frac{Plato}{258.6 - \big(\frac{Plato}{258.2} \times 227.1\big)} + 1\)

Source:

sugar.sg_to_plato(sg)

Specific Gravity to Degrees Plato

Parameters:sg (float) – Specific Gravity
Returns:Degrees Plato
Return type:float

\(\text{Plato} = \frac{\big(\text{SG} - 1\big) \times 1000}{4}\)

The more precise calculation of Plato is:

\(\text{Plato} = -616.868 + 1111.14 \times sg - 630.272 \times sg^2 + 135.997 \times sg^3\)

Source:

sugar.brix_to_sg(brix)

Degrees Brix to Specific Gravity

Parameters:brix (float) – Degrees Brix
Returns:Specific Gravity
Return type:float

Source:

sugar.sg_to_brix(sg)

Specific Gravity to Degrees Brix

Parameters:sg (float) – Specific Gravity
Returns:Degrees Brix
Return type:float

Source:

sugar.brix_to_plato(brix)

Degrees Brix to Degrees Plato

Parameters:brix (float) – Degrees Brix
Returns:Degrees Plato
Return type:float

The difference between the degBx and degP as calculated from the respective polynomials is:

\(\text{degP} - \text{degBx} = \big(\big(\big(-2.81615*sg + 8.79724\big) \times sg - 9.1626\big) \times sg + 3.18213\big)\)

The difference is generally less than +/-0.0005 degBx or degP with the exception being for weak solutions.

Source:

sugar.plato_to_brix(plato)

Degrees Plato to Degrees Brix

Parameters:brix (float) – Degrees Plato
Returns:Degrees Brix
Return type:float
sugar.apparent_extract_to_real_extract(original_extract, apparent_extract)

Apparent Extract to Real Extract in degrees Plato

Parameters:
  • original_extract (float) – Original degrees Plato
  • apparent_extract (float) – Apparent degrees Plato of finished beer
Returns:

Real degrees Plato of finished beer
Return type:

float

Source:

  • Formula from Balling: De Clerck, Jean, A Textbook Of Brewing, Chapman & Hall Ltd., 1958
sugar.hydrometer_adjustment(sg, temp, units=u'imperial')

Adjust the Hydrometer if the temperature deviates from 59degF.

Parameters:
  • sg (float) – Specific Gravity
  • temp (float) – Temperature
  • units (str) – The units
Returns:

Specific Gravity corrected for temperature
Return type:

float
Raises:

SugarException – If temperature outside freezing to boiling range of water

The correction formula is from Lyons (1992), who used the following formula to fit data from the Handbook of Chemistry and Physics (CRC):

\(\text{Correction(@59F)} = 1.313454 - 0.132674 \times T + 2.057793e^{-3} \times T^2 - 2.627634e^{-6} \times T^3\)

where T is in degrees F.

Sources:

sugar.refractometer_adjustment(og, fg, wort_correction_factor=1.04)

Adjust the Refractometer for the presence of alcohol.

Parameters:
  • og (float) – Original Gravity
  • fg (float) – Final Gravity
  • wort_correction_factor (float) – A correction to the reading given by the refractometer
Returns:

Final Gravity adjusted
Return type:

float

NOTE: This calculation assumes using Brix or Plato, so the input will be converted from SG to Plato and then converted back.

Sources: