How does overrun be calculated
"overrun" is the technical terminology used to indicate how much air an ice cream holds. In a fluffy ice cream it can be as much as 100%, that is, the final ice cream volume is half mix a-nd half air. The lower the overrun, the denser the ice cream. How does overrun be calculated? Equations are as follows:
% overrun = (vol. of ice cream - vol. of mix used)/vol. of mix used x 100%
Example : 600 L mix gives 900 L ice cream,
(900 - 600)/600 x 100% = 50% overrun
What about ice cream with particulates? For example crushed peanuts.
50 L mix plus 20 L crushed peanuts gives 120 L peanuts ice cream.
120 - 20 = 100 L actual ice cream.
% overrun = (vol. of ice cream - vol. of mix used)/vol. of mix used
= (100 - 50)/50 x 100% = 100%
If we know the density of mix (wt. of 1 L), usually 1.09 - 1.1 kg. /L. We can also calculate overrun by weight.
% overrun = (wt. of mix - wt. of same vol. of ice cream )/wt. of same vol. of ice cream x 100%
For example, if 1 L of ice cream weighs 600 g.
% overrun = (1090 - 600)/600 x 100% = 81.7% overrun
You may ask that how is the density of mix be calculated?
1 / ((% fat/100 x 1.075) + ((% t.s./100 - % fat/100) x 0.63) + (% water/100)) = wt. (kg)/ litre mix
For example: Calculate the weight per litre of mix containing 12% fat, 11% serum solids, 10% sugar, 5% corn syrup solids, 0.30% stabilizer, a-nd 38.3% T.S.(total solids)
1.0 / ((0.12 x 1.075) + ((0.383 - 0.12) x 0.63) + 0.617) = 1.096 kg/L of mix
Perhaps the following equations could be more useful in ice cream processing:
Weight of given vol. of ice cream = wt. of same vol. of mix / (desired overrun / 100 + 1)
For example: desired 90% overrun, mix density 1.09 kg/L.
net wt. of 1 L = 1.09 kg / ( 90/100 + 1) = 573.7 g
Also, density of ice cream = density of mix / (overrun/100 + 1)
For example: density of mix 1000 g/L.
100% Overrun, density of ice cream = 1000 g/L / (100/100 + 1) = 500 g/L
With particulates? A little more complicated.
For example: butter brickle ice cream, density of mix 1.1 kg/L, overrun in ice cream 100%, density of ca-ndy 0.748 kg/L, ca-ndy added at 9% by weight, (i.e. 9 kg to 100 kg final product).
In 100 kg final product, we have:
9 kg of ca-ndy (or 9 kg / 0.748 kg/L = 12.0 L)
91 kg of ice cream (or 91 kg / (1.1 kg/L / (100/100 + 1)) = 165.5 L)
So, 100 kg gives a yield of 12 + 165.5 = 177.5 L
1 L weighs 100 kg / 177.5 L = 563 grams
% overrun = (vol. of ice cream - vol. of mix used)/vol. of mix used x 100%
Example : 600 L mix gives 900 L ice cream,
(900 - 600)/600 x 100% = 50% overrun
What about ice cream with particulates? For example crushed peanuts.
50 L mix plus 20 L crushed peanuts gives 120 L peanuts ice cream.
120 - 20 = 100 L actual ice cream.
% overrun = (vol. of ice cream - vol. of mix used)/vol. of mix used
= (100 - 50)/50 x 100% = 100%
If we know the density of mix (wt. of 1 L), usually 1.09 - 1.1 kg. /L. We can also calculate overrun by weight.
% overrun = (wt. of mix - wt. of same vol. of ice cream )/wt. of same vol. of ice cream x 100%
For example, if 1 L of ice cream weighs 600 g.
% overrun = (1090 - 600)/600 x 100% = 81.7% overrun
You may ask that how is the density of mix be calculated?
1 / ((% fat/100 x 1.075) + ((% t.s./100 - % fat/100) x 0.63) + (% water/100)) = wt. (kg)/ litre mix
For example: Calculate the weight per litre of mix containing 12% fat, 11% serum solids, 10% sugar, 5% corn syrup solids, 0.30% stabilizer, a-nd 38.3% T.S.(total solids)
1.0 / ((0.12 x 1.075) + ((0.383 - 0.12) x 0.63) + 0.617) = 1.096 kg/L of mix
Perhaps the following equations could be more useful in ice cream processing:
Weight of given vol. of ice cream = wt. of same vol. of mix / (desired overrun / 100 + 1)
For example: desired 90% overrun, mix density 1.09 kg/L.
net wt. of 1 L = 1.09 kg / ( 90/100 + 1) = 573.7 g
Also, density of ice cream = density of mix / (overrun/100 + 1)
For example: density of mix 1000 g/L.
100% Overrun, density of ice cream = 1000 g/L / (100/100 + 1) = 500 g/L
With particulates? A little more complicated.
For example: butter brickle ice cream, density of mix 1.1 kg/L, overrun in ice cream 100%, density of ca-ndy 0.748 kg/L, ca-ndy added at 9% by weight, (i.e. 9 kg to 100 kg final product).
In 100 kg final product, we have:
9 kg of ca-ndy (or 9 kg / 0.748 kg/L = 12.0 L)
91 kg of ice cream (or 91 kg / (1.1 kg/L / (100/100 + 1)) = 165.5 L)
So, 100 kg gives a yield of 12 + 165.5 = 177.5 L
1 L weighs 100 kg / 177.5 L = 563 grams