Key points
- Ingredient waste comes from over-prep, spoiled stock, portion drift, wrong orders, trimmings, and spills.
- Log every ingredient thrown out for two weeks: what, how much, why, and what it cost.
- Written portions and measuring tools stop portion drift, which never shows up in the waste log.
- Compare usage by stock count with usage by recipe to find the gaps nobody wrote down.
Picture closing time at your cafe. The barista pours out the extra pot of tea brewed this morning, the cook throws away a plate of Nasi Goreng from a wrong order, and the lettuce in the chiller has gone limp. Nobody writes any of it down. The day's sales report looks normal, but you've already paid for everything that went in the bin.
One incident hardly registers. Ingredient waste only looks big once you add it up over a month. Below are where it comes from, how to track it, a worked example of what it costs, and how to cut it back one cause at a time.
Where ingredient waste comes from
| Source | Example | How to cut it |
|---|
| Over-prep | Tea brewed, vegetables cut, or sauce made beyond what sells | Prep to the day's expected sales |
| Spoiled or expired stock | Milk past its date at the back of the shelf, limp vegetables | Use the oldest stock first |
| Portion drift | A little extra milk in each cup, rice scooped a bit fuller | Written portions and measuring tools |
| Wrong orders | Drinks remade because of the wrong size or the wrong item | One order record from cashier to kitchen |
| Trimmings | Peels, stems, and vegetable ends | Trim more carefully, use good trimmings in other dishes |
| Spills and drops | A dropped glass, milk spilled while pouring | Rearrange the work station |
For stock that spoils on the shelf, read how to use FIFO and FEFO. For wrong orders, the one-record flow from cashier to kitchen is in the article on the order flow.
Log what gets thrown out for two weeks
You can't reduce what you can't see. Tape a sheet of paper near the kitchen bin or the prep table, and for two weeks write down every ingredient that gets thrown out:
| Day | Ingredient | Amount | Reason | Cost |
|---|
| Monday | UHT milk | 300 ml | Wrong order | Rp5,400 |
| Monday | Coffee beans | 36 g | Wrong order | Rp7,200 |
| Tuesday | Palm sugar syrup | 250 ml | Over-prep | Rp10,000 |
| Tuesday | UHT milk | 1 liter | Expired | Rp18,000 |
Cost = amount × unit price. You get the unit price from your receipts: purchase price divided by pack size, as in the guide to COGS per menu item. This table uses that guide's sample prices: UHT milk at Rp18 per ml, coffee beans at Rp200 per gram, and palm sugar syrup at Rp40 per ml. First row: 300 ml × Rp18 = Rp5,400.
To make the log something you can trust:
- Whoever throws something out writes it down right away, not from memory at the end of the day.
- Use the fixed list of reasons from the table above, so the totals are easy to add up.
- You or the shift lead can fill in the cost later.
- Use the log to find causes, not to blame people. If staff are afraid of being told off, they stop writing things down.
At the end of each week, add up the cost per reason. The reason with the biggest total is where you start.
A worked example: a month of waste
Every number in this section is an example, not real business data. Say your two-week log adds up like this:
| Reason | Total for 14 days |
|---|
| Over-prep | Rp84,000 |
| Spoiled or expired stock | Rp56,000 |
| Wrong orders | Rp42,000 |
| Spills and other causes | Rp28,000 |
| Total | Rp210,000 |
The daily average is Rp210,000 ÷ 14 = Rp15,000. Over a 30-day month, that's Rp15,000 × 30 = Rp450,000.
Portion drift doesn't show up in the log, because nothing is thrown out: the extra goes into the cup. Work it out separately. Say the recipe for Kopi Susu Aren calls for 150 ml of milk, but your baristas pour 170 ml on average. The 20 ml difference × Rp18 = Rp360 a cup. At 400 cups a month, that's Rp360 × 400 = Rp144,000.
The total is Rp450,000 + Rp144,000 = Rp594,000 a month. With a gross profit of Rp13,600 per dine-in Kopi Susu Aren, as in the COGS example, that equals the gross profit from about 44 cups (Rp594,000 ÷ Rp13,600 = 43.7).
Now say you cut over-prep and wrong orders in half, and the milk goes back to 150 ml a cup:
- Half of over-prep and wrong orders: (Rp84,000 + Rp42,000) ÷ 2 = Rp63,000 per 14 days, or Rp63,000 ÷ 14 × 30 = Rp135,000 a month.
- Milk back to the right amount: Rp144,000 a month.
You save Rp135,000 + Rp144,000 = Rp279,000 a month.
Write down a standard portion for every item
Portions that live only in people's heads drift, a little at a time, from one staff member to the next.
- Write down the portion for every menu item in grams, ml, or number of pieces, and post it at the bar and in the kitchen.
- Keep measuring tools at each station: a digital scale, a measuring jug, measuring spoons, or fixed-size scoops. A little or a splash is not a portion.
- Once a week, ask one staff member to make an item the usual way, then weigh the ingredients and compare them with the written portion.
- When a portion changes, such as a new cup size, update the sheet and the item's COGS at the same time.
Portions are also the basis of your COGS. If the portion at the bar differs from the one in your costing, the COGS on paper comes out lower than what you really spend.
Prep to the day's expected sales
Over-prep can come from fear of running out during the rush. To get the amount right:
- Look at how many of each item sold on the same day last week. Compare the same day, because Monday and Saturday can be very different. How to do that is in the guide to reading the daily sales report.
- Make a daily prep list: which ingredients, how much, and who preps them.
- Prep in two rounds: some in the morning, the rest before the rush, once you've seen how the morning is selling.
- Prep anything that spoils quickly once cut or brewed in smaller amounts, more often.
- At the end of the day, write down the leftover prep. If the same item is always left over, prep less of it on the same day next week.
Example: Last Saturday you sold 40 iced teas, and one pot makes 10 glasses. Instead of brewing 4 pots in the morning, brew 2 first, then brew the next pot each time the last one starts running low.
Use stock checks to find items that keep running over
The waste log only catches what gets written down. To find what doesn't, compare two numbers for your main ingredients once a week:
- Usage by stock count: opening stock + deliveries − closing stock.
- Usage by recipe: servings sold × amount per serving.
- The difference between them, minus what's already in the waste log, is the gap you can't yet explain.
Example: This week, opening stock of UHT milk was 10 liters, 24 liters came in, and closing stock was 6 liters, so you used 28 liters. You sold 160 milk drinks at 150 ml each, so by the recipe you used 24 liters. The difference is 4 liters. The waste log shows 1.3 liters of milk (the 300 ml and the 1 liter in the table above). That leaves 2.7 liters unexplained, or about 17 ml a cup (2,700 ml ÷ 160). Portion drift is the easiest cause to check, so start with the milk portion at the bar.
An ingredient whose gap shows up week after week is where to look: the portion, waste nobody wrote down, or deliveries recorded wrong. How to count stock daily is in the guide to daily ingredient stock checks.
If you use Kazeer, what you need for both calculations is in the same app as your POS. Kazeer's Inventory holds your list of items and ingredients, where you check stock and see what's left. Ingredient stock there goes down automatically with each sale, so the gap between the stock Kazeer shows and your physical count is the same as the gap between the two numbers above: ingredients used outside of sales, both the ones in your waste log and the ones not yet explained. COGS is recorded from every sale, but waste never becomes a sale, so you still keep the waste log separately.
You can ask Kazeer AI which stock is running low, for example "Which items should I check?" ("Barang apa yang perlu dicek?"). If an ingredient runs low sooner than usual while sales of the items that use it haven't gone up, check that ingredient first.
Start this week
- Put up the waste log sheet and explain the rules to your staff.
- Write down the portions for your best sellers and post them at the bar and in the kitchen.
- Make a daily prep list from sales on the same day last week.
- After two weeks, add up the cost per reason and pick one reason to cut first.
- Every week, compare usage by stock count with usage by recipe for the two or three ingredients you use most.