Question:
I just lost a ton of time, money, and patience because my staff can’t seem to scale a cake recipe correctly. What’s the best way to put a system in place so this doesn’t keep happening?
– Bakery Owner
Answer:
Scaling recipes for various batch sizes should be easy. The classic culinary school way to do this is by generating something called a conversion factor. Go through each ingredient and multiply it by the conversion factor to get the new quantity you are producing. To use a simple example, imagine that your typical brownie recipe yields 100 brownies. Your production plan demands that you make 450 brownies today. You divide your desired quantity by your standardized recipe quantity to get a conversion factor of 4.5 (450/100). You would then go through each ingredient and multiply it by 4.5 to calculate the new recipe size. For example, ten pounds of chocolate chips in a serving for one hundred would now require 45 pounds of chocolate chips.
It sounds easy, and it is, but it doesn’t mean it will be foolproof. In this labor environment, and with employees who may not have good math skills or organization, even simple arithmetic can yield large and costly mistakes as you’ve experienced.
There are a few reasons your recipe may not have worked:
1. Unclear math. One common problem is employees doing math in their head, converting some of the measurements correctly but not others. Another common problem are funky units of measure that then are converted or measured improperly. For example, imagine your standard batch needs 2.5 tablespoons of vanilla, which then becomes 11.25 tablespoons. A strange number to measure, even if converted to cups, that would be better expressed by weight (ideally in grams).
2. Special case conversions. Converting recipes is both an art and a science. If your recipe is slightly off at the smaller portion, when you convert it to a larger portion, small problems become magnified. Further, some ingredients like salt, spices and leaveners do not convert in a linear ratio.
My advice to manage converting recipes is to provide employees a recipe template to fill in (and have double checked) the math for the converted recipe. While recipe software may be reliable, it will also need to be double checked. Use weight in grams for all ingredients rather than volume measures which can be inaccurate (for example, how densely packed is the brown sugar) or Imperial, which can be confusing.
My second piece of advice is to adjust your standardized recipes to fit your equipment to reduce the amount of conversions you need to make. For example, let’s imagine you have a 30-quart mixer. Make your standardized recipe one batch that maximizes your mixer and yields a known number of product (say 6 sheet pans, for example). Then, rather than converting the recipe itself, employees are focused on how many batches to make—there is no need to scale beyond your mixer’s capacity. The other advantage of this approach is that you can test and fine tune your recipe for each batch, down to specific details such as mixing time and speeds.