Inventory control: discrepancies between your purchases and your sales
Food Waste, Inventory

Inventory control: discrepancies between your purchases and your sales

Stock control in catering: Are you sure you have sold the 6 bottles of "Mâcon" you bought last week? There are no bottles left in stock. How do you answer this question without going through all the bills or asking your team about the number of sales?

Stock control is an essential management tool for a restaurant. Indeed, it is important to analyse the data, the quantities of products that you have in stock. It is a question of controlling the differences between your theoretical stock and your real stock, which you will enter during the inventory. By following this system you will limit food waste, reduce your purchasing costs and therefore improve the overall management of your restaurant.

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For products that you resell like wine, it's pretty easy. But what method would you use when you have 5 to 10 products per recipe multiplied by the number of preparations in your restaurant?

Maybe you think it's impossible and that no one can control it!
This monitoring is extremely important! Imagine if everyone around you knew that you can't control anything...

Symptoms and Diagnosis

Most of the time, we think of the technical sheets and the quantities that are not respected to justify a deviation. If you add 20g of chicken per cutlet out of 100 pieces you have a discrepancy of 2kg. Waste is also a plague in the kitchen: too much preparation, no feedback and perhaps no methods to prepare as little as possible and no optimisation to reduce losses. But the surprising thing is that there are many other reasons for mistakes that we don't even know about.


One food supplier told me how food was being diverted in the establishments he delivered to. For example, more than 10 kg of entrecote per week was delivered to an establishment that did not offer it on its menu. I was distressed, the salesman told me that he couldn't say anything, he risked losing his contract. Selling more than 600 kg of entrecôte per year was the price of his silence. It is no longer even a question of poor management of purchasing costs and stock, it is now a pure loss for the restaurant due to a lack of control over orders and stocks.

Another story: On an American blog, I read that managers were using transparent garbage bags to visually check what was being thrown away. That same evening, I went to check the trash cans after closing, and surprise! I find a whole striploin over 7kg out of date in the first bag I open.

Perhaps becoming "paranoid", I decide to check the deliveries more closely. After buying a proper scale, the chef weighs the delivery of the yellow place. Out of 20kg, 2kg are missing. On one delivery this is not important, but imagine the costs that this can represent on a large number of deliveries.

These are only examples, but they do describe the difficulty of monitoring food consumption. To let it go is to jeopardize the business. At the risk of going out of business.


So how do you do it without spending too much time? What method can you use without making the control a pain and without demotivating everyone? How do you know what you can improve? And where to focus your efforts? How do you set up stock control?
Controlling deliveries is all very well, and this step will help you limit costs and boost your results. However, one of the biggest difficulties is calculating the quantities consumed.

It's simple:

  • on the one hand you have the goods you buy,
  • on the other hand the sales you make

The spread is what you bought but didn't sell.

The ideal solution

The best thing would be to be able to know which are the most important differences in terms of costs. After all, it would be a waste of time to monitor flour consumption because the difference is one kilo over a month. So the ideal solution is to focus on the big deviations:

  1. or in volume to limit food waste,
  2. or in euros to improve the balance sheet.

The luxury would therefore be to focus only on 2 or 3 products per period to specifically control :

  • outdated CSDs,
  • misjudged orders,
  • deliveries to be checked thoroughly,
  • or the quantities indicated in the data sheets ...

Calculation method - Stock control restoration

The comparison is made over a given period of time: for example, every month.Stock control in restoration

Theoretical quantity consumed

The first thing is to have the number of sales of each of our products over a given period. Then, establish a data sheet for each of these products. We can then multiply the two to get the quantity of foodstuffs theoretically consumed.

Target quantity consumed = number of sales * data sheet

With the use of cash register software over the last few years, we have a considerable advantage in being able to export the number of sales of each of our references over the chosen period.

Actual quantity consumed

The actual quantity consumed is easy, it is the total of all invoices for the chosen period by ingredient.

Actual quantity consumed = total invoices

Don't forget the stocks!

Indeed, inventories will be carried out at the end of the period. In the example here, it will be every month.
So we will have a beginning inventory and an end inventory.

Example for the month of May :

  • theinventory starts on April 30
  • thefine inventory is carried out on May 31

Stock variance

Finally, the calculation of the stock difference is the difference between the "Actual Quantity Consumed" and the "Theoretical Quantity Consumed". The difference in stock between the beginning and end of the period is added to this calculation.

For each foodstuff :

Difference = Actual quantity consumed - Target quantity consumed + inventory start - inventory end

The new way with koust

On paper it's simple, but the execution is less so. A lot of data and calculations are involved. This control can quickly become tedious without tools.

So, let's see how to use the management software for these restoration stock control calculations.


Here, the consumptions are imported from the cash register software. There are therefore no additional tasks to perform.

Koust immediately gives the quantities of food consumed, taking into account the technical data sheets and ingredients associated with the articles.


Koust's invoice module makes it easy to enter all your invoices. If you use the order sending module, the software transforms your orders directly into invoices.

In addition, you have the monthly total of your purchases at any time.


The inventory module allows you to value your stocks, the input is done directly in the management software or by importing a csv file. The inventory dates will also be used to calculate the differences.

In addition to the stock differences, Koust calculates the total (in euros) of your inventories.

Restocking stock check: purchase/sale differences

Finally, the difference module gives you the result directly. You only have 2 possibilities:

  1. Changing the period dates to extend or shorten your comparison period
  2. Sorting on all data: ingredient name, higher deviation, higher quantity ...

The advantage of using Koust is also that the control period can be changed:

  • 1-month stock differences,
  • over two months,
  • over six months... with one click.

The other even more interesting advantage is to be able to concentrate only on 2 or 3 products per period by sorting:

  1. in volume to limit waste,
  2. or in euros to improve the balance sheet.

How do you get it?

Finally, all these features are grouped together in the "Koust PRO" subscription.



Koust is a management software dedicated to CHR professions.
Koust allows you to optimize the profitability of your establishment.
The idea is simple: better control over quantities and costs by having more control over procurement and production.

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