### Introduction

The Miscellaneous Additions Calculator determines the amount of an additive to add to a wine to yield a desired concentration in the wine, given the initial concentration of the additive and volume of the wine. The additive can either be in the form of a solid (powder or crystals) or a liquid (stock solution).

### Input Field Definitions

Additive Type – Select from either solid (powder/crystals) or liquid (stock solution).

Solution Concentration – The concentration of the additive in the stock solution being added.  Required only if liquid (stock solution) was selected as the additive type.

Target Concentration – The desired concentration of the additive.

Initial Concentration – The current concentration of the additive.

Wine Volume – The volume of the wine being treated.

### Output Field Definitions

Mass of Additive Required – The mass of the additive required to yield the desired concentration in the specified volume of wine.  Reported only if solid (powder/crystals) was selected as the additive type.

Volume of Solution Required – The volume of stock solution required to yield the desired concentration in the specified volume of wine.  Reported only if liquid (stock solution) was selected as the additive type.

### Calculation Details

This calculation determines the amount of a substance to add to a wine to yield a desired concentration in the wine, given the initial concentration of the substance and the wine volume. The substance can either be in the form of a solid (powder or crystals) or a liquid (stock solution).

If it is being added as a liquid, the concentration of the solution must be specified. It is assumed that the volume of the additive is negligible compared to the volume of the wine, and that the increase in volume due to the addition can be ignored. If the volume of the solution addition is greater than 10% of the volume of the wine, FermCalc will issue a warning message. In this case, consider doing a blending calculation to account for the impact of the volume increase on the final concentration.

The total mass of a substance in solution is simply the initial mass of the substance plus the mass that is added, or:

 mt = mi + ma (8-6)

where:

mt = total mass of substance, kg

mi = initial mass of substance, kg

ma = mass of substance added, kg

Since mass is volume multiplied by concentration we can write:

 vwct = vwci + ma (8-7)

where:

vw = wine volume, liters

ct = total (target) concentration, kg/L

ci = initial concentration, kg/L

Rearranging and solving for ma we get:

 ma = vw(ct – ci) (8-8)

If the substance is being added as a stock solution, we need to calculate the volume of the solution to add. To do this we simply need to substitute equation (8-1) for ma in equation (8-5) and rearrange to get:

 vs = vw(ct – ci)/cs (8-9)