Storage procedures: store room, fridge and freezer – Food Storage (Senior 3 Home Science) | Ganzaa

Food Storage

Lessons

Senior 3 · Home Science

Food Storage

4 lessons

Lesson 3 of 4

Storage procedures: store room, fridge and freezer

24 min

Let's begin

Open the fridge in many homes and you find the same small disasters: a bowl of last week's isombe pushed to the back, half an onion with no cover making the milk taste of onion, and a packet of raw meat on the top shelf, its juice dripping onto a cake below. Each one is a broken storage procedure. A fridge, a freezer or a store room only keeps food safe if it is used by a set of rules: what goes where, how it is wrapped and labelled, and which item is used first. This lesson sets out those rules.

Definition

First in, first out (FIFO): a stock rotation rule: food that came in first, or has the earliest date, is used first. New stock goes behind or under old stock.

Cross-contamination: the spread of bacteria from raw food, dirty hands or equipment to food that will not be cooked again.

Freezer burn: dry, pale, tough patches on frozen food that was not wrapped airtight; the food is safe but poor in quality.

Stock card (bin card): a record kept for each item in a store showing the date, amount received, amount issued and balance.

The store room

Rotate stock (FIFO). Write the date received on every bag or tin. Put new stock behind or under old stock.
Contain it. Tip flour, sugar, rice and beans into clean, dry bins with tight lids, labelled with the name and date.
Raise it. Keep sacks on shelves or pallets at least 15 cm off the floor and away from walls, so air moves and floors can be cleaned.
Keep pests out. Seal holes and gaps, fit mesh on windows, sweep up spills at once, and look every week for droppings, gnawed bags, weevils or webbing. Remove and throw away infested food. Leave rat poison and insecticides to a trained pest-control service: never use them near open food.
Record it on stock cards, and check the balance against what is on the shelf.

The fridge

Keep it at 0–5 °C and check the thermometer daily. Do not overfill it: cold air must move round the food.
Cover every food, and label leftovers with the name and the date they were cooked.
Cool cooked food fast: divide it into shallow containers, and put it in the fridge within 2 hours of cooking.
Eat cooked leftovers within 2 days, and cooked rice within 1 day.

The freezer

Freeze food in meal-sized portions, wrapped airtight with as much air pressed out as possible, labelled with the name and the date.
Thaw food in the fridge, on a plate on the bottom shelf, or in a microwave if you cook it at once. Never thaw meat on the kitchen counter, where the outside warms into the danger zone while the middle is still frozen.
Cook thawed raw food within 24 hours. Do not refreeze raw food that has thawed; once it has been cooked, it may be frozen again.
Defrost and clean the freezer when ice is about 1 cm thick, moving the food to a cool box meanwhile.

Worked example

Worked example 1: a stock card. A school store has 40 kg of rice on 1 October. On 3 October it receives 50 kg. From 3 to 6 October it issues 12 kg a day (4 days). Complete the balance, and say which rice is used first.

Date	Received (kg)	Issued (kg)	Balance (kg)
1 Oct			40
3 Oct	50	12	78
4 Oct		12	66
5 Oct		12	54
6 Oct		12	42

Check: $40 + 50 - 4 \times 12 = 42$ kg. By FIFO, the 40 kg of old rice is used first: it runs out partway through 6 October ( $4 \times 12 = 48$ kg have been issued by the end of that day), and the new sacks are opened only then.

Worked example

Worked example 2: a fridge audit. Find the faults: raw chicken in a bag on the top shelf; a pot of hot beans put in the fridge straight from the stove in its big cooking pot; milk in the door; an unlabelled bowl of rice cooked four days ago; frozen fish thawing in a bowl on the kitchen counter.

Raw chicken on top: its juices can drip on ready-to-eat food. Move it, covered and on a tray, to the bottom shelf.
A big pot of hot beans cools slowly in the middle and warms the whole fridge. Divide the beans into shallow containers, cool them quickly and refrigerate within 2 hours.
Milk in the door: the door is the warmest part. Keep milk on a shelf.
Rice cooked four days ago: well past the 1-day limit for cooked rice; throw it away. Label leftovers in future.
Fish thawing on the counter: the outside is in the danger zone. Thaw it in the fridge on the bottom shelf.

Warning

"When in doubt, throw it out." Many food-poisoning bacteria give no smell, taste or change in appearance, so the "sniff test" cannot prove that food is safe. Throw away food that is past its use-by date, unlabelled leftovers of unknown age, and anything that has stood in the danger zone for more than 2 hours.

Tip

Memory hook for the fridge: "Ready on top, raw at the bottom." And for every container: cover, label, date.

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Practice

What does FIFO stand for, and how is it applied on a shelf?
Why is raw meat stored on the bottom shelf of the fridge?
What information should be written on a label for frozen food?
Give two safe ways and one unsafe way of thawing frozen meat.
A store holds 25 kg of sugar. It receives 30 kg and then issues 4 kg a day for 7 days. What is the balance?
Why is a large pot of hot stew divided into shallow containers before it is refrigerated?
A cook says: "Smell it; if it smells fine, it is safe to eat." Evaluate this claim.

Show answersHide answers

First in, first out: food that arrived first (or has the earliest date) is used first; new stock is placed behind or under old stock.
So that its juices, which may carry bacteria, cannot drip onto food that will not be cooked again.
The name of the food, the date it was frozen (and, if cooked, the date it was cooked), and the amount or number of portions.
Safe: in the fridge on a plate on the bottom shelf; in the microwave if cooked at once (also: in cold water in a sealed bag). Unsafe: on the kitchen counter at room temperature.
$25 + 30 - 7 \times 4 = 55 - 28 = 27$ kg.
Shallow portions cool much faster than a deep pot, so the food passes through the danger zone quickly; a large hot pot would also warm the other food in the fridge.
The claim is false. Many harmful bacteria do not change the smell, taste or look of food, so food can smell fine and still cause illness; smell only shows some kinds of spoilage. Safety depends on correct temperatures, times and dates.

Sources and credits

Lesson text, Figure 3, tables, worked examples and practice: written by Ganzaa. Fridge, leftover, rice and thawing rules follow Preparing and cooking food safely, NHS inform, and the Home food fact checker, UK Food Standards Agency, summarised in Ganzaa's own words.
Photo: Food Safety - Cut Waste in Refrigerators, United States Department of Agriculture, Wikimedia Commons, public domain.

1The store room

2The fridge

3The freezer

The store room

The fridge

The freezer