Chromabrew

Convert SRM, EBC, or a list of Lovibond values to another color scale, or to a hex color.

Color values are provided by Barley Dog Brewery here.

Usage

Install the library:

npm install --save chromabrew

Require the module:

let chromabrew = require('chromabrew');

Pass options which describe a batch to the Batch constructor, or directly to the required module. See the list of accepted options below. Call hex on the returned object to get a color:

new chromabrew.Batch({ srm: 4 }).hex();
// => '#ECE61A'

chromabrew({ srm: 4 }).hex();
// => '#ECE61A'

chromabrew({ ebc: 4 }).hex();
// => '#F8F753'

Convert between color scales:

let batch = chromabrew({ srm: 4 });

batch.srm();
// => 4

batch.ebc();
// => 7.88

batch.mcu();
// => 4.210535199414287

batch.lovibond();
// => 3.407407407407407

Specify which calculation method was used to determine the provided srm or ebc, or which method to use when converting between scales:

let batch = chromabrew({ srm: 14, calculator: 'daniels' });

batch.srm('daniels');
// => 14

// defaults to 'morey'
batch.srm();
// => 14.670088349307665

batch.srm('mosher');
// => 13.099999999999998

// defaults to 'morey'
batch.ebc();
// => 28.9000740481361

batch.hex('daniels');
// => '#B26033'

// defaults to 'morey'
batch.hex();
// => '#A85C37'

Options

Primary Options

Any one of the following options must be passed to the module:

option	description	type
`srm`	the SRM of a batch	`Number`
`ebc`	the EBC of a batch	`Number`
`l` or `lovibond`	the degrees Lovibond of a batch	`Number`
`batch`	options describing a batch in detail (see below)	`Object`

This option may be used in combination with a known color value (srm, ebc, or l) to specify which calculation method was used:

option	description	type
`calculator`	the SRM calculation method used: `'morey'` (default), `'daniels'`, `'mosher'`, or `'barry'` †	`String`

† apparently they let anyone create a beer color scale

Batch Options

The following options define the batch primary option:

option	description	type
`mcu`	the MCU of the batch, if it is already known	`Number`
`v` or `volume`	the total liquid volume of the wort (required)	`Number`
`ingredients`	an `Array` of ingredient options (see below; required)	`Array[Object]`
`litres` or `liters`	whether `volume` is expressed in litres	`Boolean`
`kilograms` or `kilos`	whether `weight` of each item in `ingredients` is expressed in kilograms	`Boolean`
`metric`	shortcut to apply both `litres` and `kilograms` options	`Boolean`

Ingredient Options

The following options define each ingredient in the ingredients batch option:

option	description	type
`l` or `lovibond`	the value in degrees Lovibond of the ingredient (required)	`Number`
`w` or `weight`	the weight of the ingredient used (required)	`Number`

Functional Domain

The domain of valid inputs is 0 through 40 SRM. Input values are rounded to the nearest 0.1 SRM within this domain:

chromabrew({ srm: -1 }).hex() === chromabrew({ srm: 0 }).hex();
// => true

chromabrew({ srm: Number.MAX_VALUE }).hex() === chromabrew({ srm: 40 }).hex();
// => true

chromabrew({ srm: Math.PI }).hex() === chromabrew({ srm: 3.1 }).hex();
// => true

The 'daniels' and 'mosher' SRM calculation scales have a minimum result of 8.4 and 4.7, respectively. Where a provided srm would result in a negative mcu, the mcu is set to 0:

let daniels = chromabrew({ srm: 4, calculator: 'daniels' });

daniels.mcu();
// => 0

daniels.srm();
// => 0

daniels.srm('daniels');
// => 8.4

let mosher = chromabrew({ srm: 4, calculator: 'mosher' });

mosher.mcu();
// => 0

mosher.srm();
// => 0

mosher.srm('mosher');
// => 4.7