The Blend Tank
The Blend Tank is a 1000-gallon stainless steel blender where
we combine ingredients for the three different blends that make up
our product base mixes. From these 3 blends we can make 56 different
flavors of ice cream.
The three base mix blends are as follows:
- Sweet Cream Base consists of cream, condensed milk,
egg yolks, liquid cane sugar, and two natural stabilizers: guar gum
(which comes from the guar tree) and carrageenan (which is a type
of seaweed). This is the base for our ice cream.
- Yogurt Base consists of condensed skim milk, egg whites,
liquid cane sugar, a little cream and natural stabilizers. This is the
base for our yogurt.
- Chocolate Base: For a chocolate ice cream or yogurt base
mix we simply add 400 pounds of Royal Dutch Cocoa Powder to each
1000 gallon batch.
In the overall ice cream production scheme of things, making the mix --
and making it most excellent -- is perhaps the most important part of the
whole process. Mix making procedures are performed by a very skilled and
experienced person known as the Mix Master. Just as a Master Chef must
measure and mix and test (and taste!) everything to prepare a recipe
perfectly, the Mix Master must be equally precise when following Ben &
Jerry's mix making recipes. As you can imagine, a mix-up in the mix-making
process can result in a thousand-gallon mess of mix we can't use.
(And that's not all -- the production schedule can get messed up too,
which can cause delivery delays, increased costs of labor and supplies, and a
mess of other things..)
To start the mix making process, the required ingredients are pumped
from their storage areas through a series of valves and pipes that
eventually lead to the Blend Tank. The Mix Master combines the correct
amounts of mix ingredients, then starts up the Blend Tank's high speed
agitator and moveable deflecting plates. These plates are positioned near
the outside wall of the tank to direct the ingredients in towards the
agitator as the liquid mix churns in a circular motion.
The completed batch of mix is then transferred through one of two
strainers into the Surge Tank. The Surge Tank is where the mix is
stored until it is ready to begin the pasteurization process. The strainers
prevent any unwanted material (such as egg shells) from getting into the
final product. The transfer is made on a space available basis, so the
amount of time needed for the transfer may vary depending on the contents
of the surge tank.
After the surge, it's time to urge the mix through a double-whammy combo
of machines that deliver a double-dose of quality to the finished
product. The Pasteurizer and The Homogenizer are separate
machines, but they process the mix together as a team. They do this
so rapidly that it's hard to explain the workings of one without
explaining the other, but since it's hard to read about both at the
same time, let's begin with