Keeping mithai and baked goods fresh: what packaging can and cannot do

A box of kalakand and a box of besan laddoo can look the same on your counter. One should be eaten today. The other can last for weeks.

Packaging can slow spoiling. It cannot stop it.

For milk sweets, temperature does most of the work and the box does very little, however beautiful it is. For dry sweets, cakes and namkeen, a closed pack that keeps out air and moisture does most of the work. So the first step is to understand how each sweet goes bad.

Then we match the pack to it. If a sweet shop asked us for one box for every product on its counter, this is the conversation we would have first.

We sell packaging at Jagannath Polymers, so it would suit us to say that a better box solves freshness. For a milk sweet, it does not. I would rather you hear that from a packaging maker than learn it from a customer complaint.

How long does each kind of sweet last?

FSSAI has given an illustrative list in its Guidance Note on Safety and Quality of Traditional Milk Products (Guidance Note 14/2020, dated 24 February 2020). We have shortened it here:

So kalakand sits in the same-day group, kaju katli in the 7-day group and besan laddoo in the 30-day group. That spread, from the same day to about 30 days, is the whole reason one box cannot suit every sweet. I find the spread more useful than any single number in the list.

The note itself says it has no force of law. I am a packaging maker, not a food technologist, so please treat these as the starting points FSSAI gives and not as my numbers. Your own recipe and your own shop decide the real figure, and the test at the end of this guide shows how to find it.

Why each kind of sweet goes bad

1. Milk sweets made from khoya, chhena or rabri hold a lot of moisture and milk protein. Microbes multiply quickly in them at a warm room temperature. A box keeps out dust and hands, but it does nothing about temperature.
2. Sweets in syrup, such as rasgulla and gulab jamun, carry the same milk risk. The syrup also leaks and stains, so they need a sealed tin or a sealed cup, and they need refrigeration.
3. Dry and ghee-rich sweets, such as besan laddoo, kaju katli and soan papdi, contain very little water. They go stale when the fat oxidises, i.e. reacts slowly with the oxygen in air, and heat and light speed that up. In the monsoon they also absorb moisture from the humidity in the air and go soft.
4. Namkeen loses its crunch to moisture, and its oil turns rancid with air and light. A box alone does almost nothing for it. It needs a sealed pouch with the right barrier.
5. Cakes and bakes split two ways. Fresh cream cakes and pastries behave like milk sweets and need the fridge. Sponge cakes, cookies and rusks suffer from air instead: sponge dries out, and cookies and rusks go soft by absorbing moisture.

Box, tin or sealed pack?

A paper box is not airtight. It protects the sweets from crushing, dust and handling, and it carries your brand. It does not keep out humid air.

So the first question we would ask is how long the sweet must stay good after it leaves your counter.

1. One or two days: a clean, food-grade box is enough. Refrigeration matters far more than the box.
2. Up to 7 days for dry sweets: a box with a liner and a well-fitting lid, kept away from heat and direct sunlight.
3. Longer, or for travel and gifting: a sealed inner pack. That can be a heat-sealed pouch, a tray sealed with lidding film, or a tin with a tight lid, placed inside the gift box.

The FSSAI packaging regulations give similar options for sweets and confectionery in their suggestive list (Schedule IV): metal containers, heat-sealed laminated pouches, thermoformed trays and punnets with lids, and glass containers with caps. Which material is safe next to the sweet is covered in our guide on food-safe packaging for mithai.

One warning. Sealing a milk sweet does not make it last longer at room temperature, and sealing it while it is still warm can make it worse.

Cool the sweets before they go in the box

This step costs nothing, and it is the easiest one to skip in the Diwali rush. I would make it a fixed rule for every karigar in the kitchen.

Warm sweets give off steam. In a closed box, that steam meets the cooler lid and turns back into water. This is condensation. The water drips onto the sweets, the surface goes soggy and mould gets an easy start.

Spread fresh sweets on clean trays, keep them covered against dust and flies, and box them only when they are at room temperature all the way through.

Barfi that is cold on top and warm in the middle is still warm.

Fridge rules for your shop and for your customer

1. Keep milk sweets in a refrigerator or a chilled counter unless they will be sold the same day. The FSSAI list puts Bengali sweets in the refrigerator.
2. Keep them covered in the refrigerator. The cold air dries out the surface of a sweet, and strong smells from other food travel to it.
3. Take care when you take them out. A cold sweet in warm air gathers water on its surface, the same way a cold glass of water does in June. Let the closed box sit until it reaches room temperature, then open it.
4. Print the storage line on the box. "Keep refrigerated. Eat within 2 days" helps the customer more than any decoration. Our guide to FSSAI labelling for sweet shops explains when such a line is required.

Do not mix wet and dry sweets in one box

Moisture moves from the wet sweet to the dry one. Put a piece of kalakand next to soan papdi, and the soan papdi will start to lose its crispness.

Strong flavours such as kesar, rose and elaichi can also travel between pieces.

We would use separate cups or a partition, or better still separate boxes.

A mixed box also takes the shortest shelf life of anything inside it. One milk sweet in a box of dry sweets sets the date for the whole box.

On the counter

1. Keep trays covered, in a glass counter if you can.
2. Keep milk sweets in the chilled section, not next to the warm namkeen.
3. Make smaller batches more often in summer.
4. Sell the oldest tray first. Put the date card on the tray so your staff can see it as well as your customers.

Find your own shelf life: a test you can run

A sweet made in May does not behave like the same sweet made in December. So I would test your own, in your own season.

1. Take one normal batch. Pack at least 6 boxes in the exact pack you sell.
2. Keep them where they will really sit: the counter, the store room or the fridge.
3. Note the temperature and the humidity each day. A small room thermometer with a humidity reading is enough.
4. Open one box each day. Check the smell, the look and the feel. Look for mould, a sour or stale smell, a sticky or slimy surface, hard edges or a rancid taste in the ghee.
5. Do not taste anything that smells sour or shows mould. Throw it away.
6. The day you see the first change is the end of the shelf life. Set your date a safe margin before that day.
7. Repeat the test 3 times a year, in summer, in the monsoon and in winter, and use the shortest result.

If you sell packed sweets beyond your own counter, also send samples to a NABL-accredited laboratory for microbiological testing before you print a long date. A smell test cannot detect microbes, and we would not print a 30-day date on the strength of a smell test alone.

What packaging cannot do

It cannot rescue a stale batch, poor kitchen hygiene or a warm shop. We make films, papers and protective packaging, and none of it replaces a refrigerator. A sealed pouch cannot stop milk from going sour if the sweet sat out too long before packing.

What good packaging can do is keep clean sweets clean, keep air and moisture away from dry sweets, and carry the right storage instruction to the customer.

We think that is plenty to ask of a box.

If your sweets have to travel, our guide on how to ship sweets and cakes by courier is the next one to read.

Which sweet goes off first in your shop? I would start your test with that one, this week.