in my experience when catering for a party there are a few questions you need to ask before working out how much meat to buy

In this case my engagement party will have 106 people.

Below is my variables and reasoning

**How much meat?**- (for main course)

you want to work out how much meat each person will have at your event. if its a sit down event then i would suggest that about 250-400g is about what you want

(think of a 400g Steak) and your customers will go home happy. however if you take into consideration the consumption of bread (burgers) and orderves then im going to go for 250.

demographic, lunch/dinner, event type ect all have effect on this.

**how many people?**

This is pretty simple but you do need to cater for (in some cases) children, people turning up with no rsvp and people leaving early.

usually you just run the RSVP number which caters for people extra when taking into account the lower consumption of children.

**Yield of usable meat**

This is the one that most people completely forget about

Pork shoulder, lamb shoulder, beef brisket all have 2 "losses" that you need to take into consideration

"trimming and evaporation"

-Evaporation is on average 30% of the yield lost

-trimming is variable depending on the cut.

In my case for a full packer brisket i loose about 15% trimming and another 30% of lost evaporation. I can make up some of this evaporation by foiling the cut and keeping the juices to re-add

For my calculations i will go with a 60% yield based on 40% loss

-Pork butts from costco have a 25%-35% loss and full pork shoulders (all fat on and bone in) can have as high as 50% loss

Here are my calculations

[How much meat?] x [how many people?] x 1.[yield loss i.e .4]

so for instance for 100 people at 250 grams and 35 % loss it would look like this

250 x 100 x 1.35 = 33750 grams or 33.75kg of meat for a 25kg yield which is required

I have created a nigty Spreadsheet here to do the calculations for you.

If you have any questions let me know

BBQ EVENT CATERING CALCULATOR

Event Calculator Spreadsheet by Brett Robinson, on Flickr