Prep and batch cook safely: cooling, portions and freezing

One prep session run from a written order of work, food divided into shallow containers and refrigerated within 2 hours, every container labelled, and each portion marked eat by or freeze by.

1. Kinds of prep Understand

Prep, in this manual, is any work done ahead so a later meal takes less time: washing and chopping, cooking parts of meals, cooking whole dishes in quantity, or filling the freezer. The extension sources name several kinds. Utah State's Create Better Health guide separates batch cooking (making multiple servings at once for future meals), meal prepping (getting ingredients ready in advance), freezer cooking and once-a-month cooking (Utah State, Create Better Health: Frugal Meal Planning). They differ in how much rests on the fridge and how much on the freezer.

Ingredient prep. EPA's Smart Prep sheet says that when you get home from the store, wash, dry, chop and slice fresh food and put it in clear containers for snacks and easy cooking (EPA, Smart Prep: Prep Now, Eat Later). Colorado State's busy-families guide chops a week's onions at once, or browns ground meat for two meals while the pan is hot (Colorado State Extension, Meal Planning for Busy Families). One exception: EPA's Preventing Wasted Food At Home page says to wash berries, cherries and grapes only when you are ready to eat them.

Components. Illinois Extension's "Cook Once, Eat Twice" is the method behind Jordan's week: cook chicken, roasted vegetables and rice one night, then add tortillas and salsa the next night for tacos (Illinois Extension, Making the Most of Your Cooking Time).

Batches and freezer meals. NC State's Watauga County agent lists "cook once, eat twice", large batches of protein and vegetables, and meal-sized portions for the freezer among eight tips (N.C. Cooperative Extension, Watauga County, Meal Prep and Planning). Start here uses the smallest version: one dish, two meals.

This manual makes no claim about how much time or money prep saves. Clemson notes a cost on the other side: cooking, freezing and reheating uses more fuel than cooking from scratch (Clemson HGIC, Freezing Prepared Foods). Which kind fits is set by your cooking nights, your time and your freezer space.

If you answered "Not sure yet" about prep time in setup, start with the smallest kind that fits your next cooking night: one dish made for two meals. After one week you will know whether you have an hour on one day (a batch), a few minutes most days (ingredient prep), or a longer session (Go deeper, below).

2. A written order of work

An order of work is a short written list of the steps of a prep session in the sequence you will do them. It is our own method, built from the federal steps below: it puts the checks that are easy to forget (a thermometer reading, fridge space, containers ready, the 2-hour clock) at the points where they are needed. It is not a recipe; you cook the dish the way you already do.

The prep session sheet carries this order as a checklist with a note column:

1. Before you start: read the fridge and freezer thermometers and clear space in both. Set out shallow containers, lids, labels and a marker.
2. Allergy households: prepare the allergy-safe food first, with clean tools, and cover it (cross-contact).
3. Produce first, then raw meat. Rinse and dry produce, then handle raw meat on its own board (washing).
4. Start the longest-cooking item first, so it is not the last thing still hot at the end.
5. Check doneness with a food thermometer against FSIS's chart (temperatures).
6. Divide into shallow containers and refrigerate promptly, within 2 hours of the end of cooking, or 1 hour above 90 °F (cooling).
7. Label every container: name, day made, servings, eat by or freeze by (labels).
8. Freeze portions you will not eat in the fridge window, in one layer (freezing).
9. Update the freezer list and the batch sheet, then wash boards, tools and counters.

For one dish this is a few lines. Write it anyway the first time, so cooling and labels are planned before the food comes off the heat. Test it

3. Produce, raw meat and cooking temperatures

FDA's produce page says to wash all produce under running water, including homegrown and farmers market produce and produce you will peel, so dirt and bacteria are not carried from the surface when you peel or cut it. It says soap, detergent and commercial produce washes are not recommended, because produce can absorb them; firm produce such as melons and cucumbers can be scrubbed with a clean brush; and drying with a clean cloth or paper towel further reduces bacteria on the surface. Bagged produce labelled pre-washed or ready-to-eat needs no further washing (FDA, Selecting and Serving Produce Safely). FoodSafety.gov's four steps (clean, separate, cook, chill) give the same produce rule and the two-board rule (FoodSafety.gov, 4 Steps to Food Safety).

In the order of work, produce comes before raw meat so the board and knife go from clean food to raw meat, not the other way. Raw meat waiting in the fridge sits in a container or sealed bag on a low shelf, where it cannot drip on other food, as FoodSafety.gov describes.

Cooking to a safe temperature

This manual does not teach cooking technique. Cook the dish the way you already do, and check it with a food thermometer. A food thermometer is a probe thermometer pushed into the food; it is a different tool from the appliance thermometer in the fridge from Kitchen inventory. FoodSafety.gov says to put it in the thickest part of the food. FDA's safe-handling page and CDC both say a food thermometer is the only way to tell that meat, poultry, seafood and egg dishes are safely cooked. Test it

FSIS's full chart has more rows, including ham (FSIS, Safe Minimum Internal Temperature Chart). Write the temperature for your dish on the order of work, next to "check doneness".

4. Shallow containers and the 2-hour rule

Bacteria grow most rapidly between 40 °F and 140 °F (4 °C and 60 °C), FSIS's danger zone, doubling in as little as 20 minutes. Cooked food passes through that range on its way to the fridge, and the goal of cooling is to get through it fast. FSIS's leftovers page gives the home rule: refrigerate leftovers within 2 hours (1 hour above 90 °F), divide large amounts into shallow containers so they cool quickly in the refrigerator, and cut roasts, hams and whole poultry into smaller parts (FSIS, Leftovers and Food Safety).

Why shallow? Heat leaves food through its surface. A 2-inch layer of chili spread across a container has far more surface for its volume than the same chili 8 inches deep in the pot, and its center is close to a cold wall. That is why FSIS says to divide, not to wait.

How shallow. A shallow container, in this manual, is one filled no more than 2 inches (5 cm) deep with cooked food going into the fridge: Nebraska Extension's page on meals for one or two says hot food in the fridge should be no more than 2 inches deep, and NC State and Clemson give 2 inches for thick foods such as chili and stew. Other sources allow deeper containers for thinner foods; Go deeper has the comparison.

Hot food can go straight in. FSIS says hot food can be placed directly in the refrigerator, or in an ice or cold-water bath first. NDSU Extension says the same, and to speed chilling it puts containers in an "ice bath" in the sink and stirs occasionally (NDSU Extension, Questions and Answers About Storing Food in the Refrigerator). FDA adds that putting hot food in the refrigerator does not harm the appliance. An ice bath is a sink or large bowl of ice and cold water that the container of food sits in; NC State uses half ice and half water.

Leave space around the containers. FDA's storage page says not to crowd the fridge so tightly that air cannot circulate, and Clemson warns that an overcrowded refrigerator can warm up.

Check it if you want to know. An appliance thermometer beside the new containers, read an hour later, shows whether the fridge held at 40 °F (4 °C) or below under the load. Test it

5. The 3- to 4-day window and labels

FSIS says cooked leftovers keep 3 to 4 days in the refrigerator, and that is the window a prep day works inside. Its freezing page says it directly: freeze leftovers within 3 to 4 days (FSIS, Freezing and Food Safety). Illinois Extension says the same: eat refrigerated cooked leftovers within 3 to 4 days, or freeze them within that time (Illinois Extension, Leftovers).

This manual turns the window into weekdays by counting the day the food was cooked as day 0, our convention used by the keep-until calculator. Cooked Sunday, the window runs to Wednesday or Thursday, and Thursday is the last day, not a target. For planning, we put Sunday's batch on Monday through Wednesday and treat Thursday as a margin for a changed plan; that is a scheduling choice, and the federal limit is the one in the table. Any portion that will not be eaten by the last day goes into the freezer by then, and earlier is better for quality.

A plan built on one Sunday prep day therefore has a gap at the end of the week. Thursday is the last day for Sunday's batch, so Friday's dinner (and Thursday's, if you want a margin) comes from the freezer, from a second short cooking night, or from food cooked fresh. The weekly plan put the shortest-keeping meals early for that reason (perishables first).

Labels

A label turns a container into a decision someone can read. The National Center for Home Food Preservation (NCHFP) lists what a freezer label carries: the product name, any added ingredients, the packaging date, the number of servings or the amount, and the form (NCHFP, Packaging and Labeling Foods). Illinois Extension labels refrigerated leftovers with the day the food was prepared, on a removable label or a sticky note, and moves food that will spoil first to the front.

This manual's label is short enough to write in a few seconds:

• Fridge: name, day made, eat-by day. For example: "Chili, Sun, eat by Wed/Thu".
• Freezer: name, date frozen, servings or amount, and a use-by-for-quality month if you like. For example: "Chili, Sun 10/18, 2 cups, frozen".

Use tape and a marker that work on cold, damp lids; NCHFP names freezer tape, marking pens and freezer labels. In a shared fridge, add your name; in an allergy household, mark the allergy-safe containers the way the rules in The people at your table say (allergies). Clear containers, as EPA and Illinois suggest, show what is inside.

6. Freezing: portions, speed and containers

Freezing pauses food; it does not clean it. FSIS says freezing to 0 °F (-18 °C) inactivates microbes but does not kill them, and that food stored constantly at 0 °F stays safe, with only quality suffering over time. NCHFP says the same in four words: freezing does not sterilize foods. So the food that goes into the freezer has to be safe going in: cooked, refrigerated within 2 hours and frozen inside its fridge window. When it comes out it is handled like any other perishable.

Portion before you freeze. NCHFP says to pack foods in quantities that will be used for a single meal and to cool food before packaging. A single-meal portion freezes and thaws faster and leaves nothing to refreeze. Penn State freezes casseroles in shallow containers sized for one meal or one serving (Penn State Extension, Make-Ahead Freezer Meals to the Rescue).

Freeze fast. FSIS says a food 2 inches thick should freeze completely in about 2 hours, and to spread packages in one layer and not stack them until they are frozen solid. NCHFP adds that food frozen too slowly may lose quality.

Do not overload the freezer. NCHFP's freezing pointers say to add only as much unfrozen food as will freeze within 24 hours, usually 2 to 3 pounds of food per cubic foot of freezer space, because an overloaded freezer freezes slowly (NCHFP, Freezing Pointers). Clemson's freezing page gives the same figure. A freezer's capacity in cubic feet is on its label or in its manual. Product-specific

A fridge's top freezer. FSIS says a refrigerator's freezing compartment that cannot hold 0 °F is for short-term storage only. The freezer reading in Kitchen inventory tells you which kind yours is (thermometers).

How long. Freezer times are quality limits, not safety limits. Penn State says frozen meals should be used within three months for the best quality, and FSIS's leftovers page gives 3 to 4 months for frozen leftovers; its freezer chart gives 2 to 3 months for casseroles and for soups and stews. Put each dish on the freezer list and use the oldest first.

Containers that work in a freezer

NCHFP's containers page says freezer packaging should be moisture-vapor resistant, durable and leakproof, not brittle or cracking in the cold, resistant to oil and water, protective against odors, and easy to seal and mark (NCHFP, Containers for Freezing). In practice:

Clemson's freezing page gives a sizing rule of thumb: a quart holds 4 to 6 servings and a pint 2 to 3, with wide openings easiest to empty. NCHFP says not to freeze fruits and vegetables in containers larger than half a gallon, because they freeze too slowly. Whether a particular container may go in the freezer, the microwave or the oven is on its own label. Product-specific

What freezes poorly

Some foods are safe frozen but come out worse. NCHFP's list of foods that do not freeze well is the fullest (NCHFP, Foods That Do Not Freeze Well):

• Salad vegetables (lettuce, celery, cucumbers, cabbage, radishes, parsley): limp and water-logged.
• Baked or boiled potatoes: soft, crumbly and mealy, which is why Clemson leaves potatoes out of stews meant for the freezer.
• Cooked pasta or rice frozen alone: mushy. In a casserole or soup they fare better.
• Cooked egg whites, meringue, cream and custard fillings, milk sauces, sour cream and mayonnaise: rubbery, weepy or separated. FSIS's freezing page also names mayonnaise, cream sauce and lettuce.
• Crumb and cheese toppings and fried foods: soggy. Penn State freezes toppings separately.
• Seasonings: pepper, cloves, garlic and some herbs get stronger or bitter; onion and paprika change; salt loses flavor. NCHFP says to season lightly before freezing, and Clemson adds spices at serving.

FSIS names canned food (in its can) and eggs in their shells as the exceptions to what can be frozen. Freeze a dish without the part that fails (the potatoes, the topping) and add it when you reheat.

7. Thawing and packed lunches

To thaw food is to bring it from frozen back above freezing. FSIS's "Big Thaw" page gives three safe methods (FSIS, The Big Thaw: Safe Defrosting Methods):

Cooked dishes can be reheated without thawing. FSIS's leftovers page says frozen leftovers can be reheated without thawing, soups and stews in a saucepan or microwave and casseroles in an oven or microwave; FSIS's freezing page says it takes about half again as long. NCHFP says most cooked or prepared foods need no thawing before heating. Either way, reheat to 165 °F (74 °C) and bring soups, sauces and gravies to a rolling boil; Leftovers and using it up covers reheating, and when food may be refrozen is in refreezing.

For a plan, write "move to fridge" on the day before a frozen portion's dinner, so the slow, safe method is the easy one.

Packed lunches

A leftover packed for lunch spends the morning outside a refrigerator, so the 2-hour rule travels with it. FSIS's bag-lunch page and Clemson's bag-lunch fact sheet agree on the core (FSIS, Keeping "Bag" Lunches Safe; Clemson HGIC, Bag Lunch Safety):

• An insulated, soft-sided bag with at least two cold sources: two frozen gel packs, or one gel pack and a frozen juice box or water bottle. Clemson puts one cold source at the bottom, the perishable food in the middle and the other on top. FSIS says gel packs should be at least 5 × 3 inches.
• Pack the bag right before you leave. Preparing the food the night before is fine; Nebraska Extension says to keep the perishables refrigerated until you leave (Nebraska Extension, Packed Lunch Safety).
• Use a refrigerator at work if there is one, with the bag's lid open so the cold air reaches the food (FSIS).
• Throw away perishable leftovers after lunch rather than bringing them home, FSIS and Clemson say, along with used packaging. Clemson notes gel packs keep food cold until lunchtime but generally not all day.
• Hot lunches: FSIS preheats an insulated container with boiling water, then fills it with hot food and keeps it closed, so the food stays at 140 °F (60 °C) or above. Food reheated in a workplace microwave goes to 165 °F (74 °C).

Some foods need no cold source: FSIS lists whole fruits and vegetables, hard cheese, canned meat and fish, chips, bread, crackers, peanut butter, jelly, mustard and pickles. A leftover packed for lunch counts against the same 3- to 4-day window; Nebraska Extension makes extra of a main dish and eats it a day or two later as a packed lunch.

9. See it: the Delgados' chili See it

Free sources behind this chapter:

• FSIS, Leftovers and Food Safety: the federal cooling, storage, thawing and reheating rules on one page.
• NCHFP, Freezing Pointers: the freezer loading limit and how to set the freezer before a large load.
• NCHFP, Foods That Do Not Freeze Well: a table of foods and what freezing does to each, with the seasoning notes.

10. Practice: one dish for two meals Practice

Minimum: one dish from your plan cooked for at least two meals, divided into shallow containers and refrigerated within 2 hours, labelled, with any portion past the window frozen, and a batch-sheet row for each container. Time: your usual cooking time plus about 20 minutes. Materials: the fridge and freezer thermometers from Kitchen inventory, a food thermometer if the dish has meat, poultry, fish or eggs, a few shallow containers with lids, tape and a marker, and a bowl or sink for an ice bath.

1. Pick the dish. Choose a planned-leftover meal from your plan in The weekly plan, one that freezes well if part of it will go to the freezer (freezes well).
2. Write the order of work on the prep session sheet, with the dish's safe temperature from FSIS's chart.
3. Read both thermometers and clear space in the fridge, and in the freezer if a portion will go there.
4. Cook the dish the way you usually do, produce before raw meat, and check the temperature in the thickest part.
5. Divide it into shallow containers about 2 inches deep. Use an ice bath first if the batch is large or the fridge is full. Note the time.
6. Label each container with the name, the day and the eat-by day; use the keep-until calculator if you want the weekdays worked out.
7. Freeze any portion not planned within the window, in one layer, labelled with the date and amount.
8. Record it. Add a row per container or set on the batch sheet and each frozen portion to the freezer list. Put the frozen portion's dinner on next week's plan.

11. Your kitchen Your kitchen

12. Check your work Check your work

Criteria

• Was the order of work written before cooking, with the safe temperature on it?
• Was the cooked food checked with a food thermometer (for meat, poultry, fish and egg dishes)?
• Was every container about 2 inches deep or less, and in the fridge within 2 hours of the end of cooking?
• Does every container have a name, a day made, and an eat-by or a frozen date?
• Is every portion that will not be eaten by its eat-by day in the freezer, frozen inside the window?
• Does the batch sheet have a row for each container or set, and the freezer list each frozen portion?

Worked example

The Delgados' chili (fictional) meets each criterion: Pat wrote five lines on the prep sheet before cooking; the containers were filled about 2 inches deep and in the fridge inside 2 hours, with the time noted; all eight carry labels; the six frozen portions went in on Sunday, day 0 of the window; the batch sheet has two rows and the freezer list six. Chili has meat, so the criterion on temperature asks for a reading; Pat checked the pot, which the sheet notes. What the criteria cannot show is how the chili tastes after freezing, which the first thawed portion will tell them.

Common mistakes

• Leaving the pot on the stove "to cool down first". The 2 hours run from the end of cooking to the refrigerator, and a deep pot cools slowly on the counter.
• Putting one deep container in the fridge instead of several shallow ones.
• Stacking warm containers in the freezer, so the middle ones freeze slowly.
• Labelling with the day the food was portioned instead of the day it was cooked.
• Planning Friday's dinner from Sunday's batch without freezing it, so it is past its window.
• Thawing a frozen portion on the counter because there was no plan to move it to the fridge.
• Washing raw chicken in the sink before cooking it.

What is still unresolved

This chapter cannot tell you how a dish you cook freezes; the first thawed portion does. It does not settle how much prep your week needs: one dish for two meals is the minimum, and the review in Review and adjust shows whether more prep or less would have helped. Whether a specific container is still safe is not something this manual judges; the eat-by day and the federal rules are the guide, and when in doubt, it is thrown out.

13. Knowledge check and scenario

Checklist

• I wrote an order of work for one dish that feeds two meals.
• I divided it into shallow containers and had it in the fridge within 2 hours.
• Every container is labelled with the name, the day made and an eat-by or frozen date.
• Labelled containers are in the fridge or freezer and the batch sheet has a row for each.
• I read the fridge thermometer an hour after loading it with the new containers. (Go deeper; optional)
• I packed a planned leftover as a lunch with two cold sources. (Go deeper; optional)