Formula Preparation Guide - PSPEN

WHO & PSPEN Guidelines

Home Nutrition
Formula Preparation
Guide

A comprehensive evidence-based guide for safe preparation, storage, and handling of infant & enteral nutrition formulas at home.

Start Guide

🍼Safe & Clean

✅WHO Approved

8Key Steps

70°CSafe Water Temp

2hrMax Feed Time

24hrFridge Storage

Why Safe Formula Preparation Matters

Improper preparation of formula feeds can lead to serious infections and nutritional imbalances. This guide follows WHO and PSPEN recommendations to ensure maximum safety.

Infection Prevention

Powdered formulas are not sterile. Proper preparation at 70°C kills harmful bacteria like Cronobacter sakazakii & Salmonella.

Correct Concentration

Too dilute or too concentrated formula can cause serious harm — electrolyte imbalance, dehydration, or kidney overload in infants.

Optimal Nutrition

Following correct steps ensures your baby receives the right amount of nutrients, vitamins, and calories for healthy growth & development.

Equipment Needed

Ensure all equipment is clean, sterilized, and ready before preparing formula.

🍼Feeding BottlesBPA-free

🫧Bottle BrushFor cleaning

♨️SterilizerSteam/boil

🥄Formula ScoopLevel scoops

🌡️ThermometerFood grade

🔪Clean KnifeLevel scoops

Step-by-Step Preparation

Follow these 8 essential steps for safe formula preparation based on WHO & PSPEN guidelines.

Clean & Wash Hands

Wash your hands thoroughly with soap and warm water for at least 20 seconds. Dry with a clean towel. Clean and disinfect the preparation surface.

This is the most critical infection prevention step

Boil Fresh Water

Boil fresh, clean drinking water (whether tap or bottled). Use a kettle or covered pot. Do not re-boil previously boiled water. Do not use water that has been boiled in a microwave.

Cool to 70°C (No Lower)

Allow the boiled water to cool for no more than 30 minutes to reach approximately 70°C. This temperature is hot enough to kill harmful bacteria in the powder but not so hot as to destroy all nutrients.

Warning: Water below 70°C may not effectively kill bacteria. Use a food thermometer if available.

Sterilize Feeding Equipment

All bottles, nipples, caps, rings, and any utensils used should be sterilized using one of the following methods:

Boiling: Submerge in boiling water for at least 5 minutes

Steam sterilizer: Follow manufacturer's instructions

Chemical sterilization: Use approved tablets/solution

Pour Water into Bottle

Pour the required amount of warm (70°C) water into the sterilized bottle. Check the water level at eye level on a flat surface for accuracy. Always add water before the formula powder.

Add Exact Scoops of Formula

Using the scoop provided in the formula tin, add the exact number of level scoops as directed on the label. Use a clean, sterilized knife to level each scoop.

Important: Never pack, heap, or compress the powder. Never add extra scoops "for goodness." The scoop-to-water ratio varies between brands — always follow your specific product's instructions.

Mix & Cool the Formula

Secure the cap/nipple on the bottle and shake or swirl gently until fully mixed. Cool rapidly by holding the bottle under cold running water or placing in a container of cold water. The feed should reach body temperature (37°C) — test on your inner wrist.

Feed Your Baby

Feed the baby immediately once the formula has cooled to the right temperature. Hold the baby in a semi-upright position. Discard any remaining formula within 2 hours of the start of a feed.

Never: Use a microwave to heat formula — it creates dangerous hot spots. Never re-use leftover formula from a previous feed.

Standard Dilution Chart

General reference chart. Always follow your specific formula brand's instructions as ratios may vary.

Feed Volume (ml)	Boiled Water (ml)	Level Scoops	Approx. kcal
60 ml	60 ml	2 scoops	~40 kcal
90 ml	90 ml	3 scoops	~60 kcal
120 ml	120 ml	4 scoops	~80 kcal
150 ml	150 ml	5 scoops	~100 kcal
180 ml	180 ml	6 scoops	~120 kcal
210 ml	210 ml	7 scoops	~140 kcal
240 ml	240 ml	8 scoops	~160 kcal

Note: Standard dilution is typically 1 level scoop per 30 ml of water (~67 kcal/100 ml). Always verify with your specific product label. Premature or sick infants may require specialized concentrations as prescribed by their healthcare team.

Storage & Safety Rules

Prepared Formula

Use within 2 hours at room temperature
Store in refrigerator (≤4°C) for up to 24 hours
Re-warm by placing in warm water — never microwave
Discard any feed that baby did not finish
Never re-freeze or re-heat formula more than once

Opened Powder / Tin

Store in a cool, dry place — not in the refrigerator
Use within 4 weeks of opening (or as per label)
Write the opening date on the tin
Keep the lid tightly sealed after every use
Discard if past expiry or if powder looks clumpy/discolored

Transporting Formula: When traveling, carry pre-measured powder in a clean, dry container and a thermos of boiled water (70°C+). Prepare the feed just before feeding time. Alternatively, carry a freshly prepared bottle in an insulated cool bag with ice packs and use within 4 hours.

Types of Formula

📦

Powdered Formula (PIF)

Most common and economical. Requires careful preparation with boiled water at 70°C. Not sterile — must follow all preparation steps carefully.

Most Common

🧴

Liquid Concentrate

Requires dilution with previously boiled water as per label instructions. Partially sterile. Use within 48 hours of opening. Refrigerate unused portion.

Semi-Prepared

🥛

Ready-to-Feed (RTF)

Pre-mixed and sterile — safest option especially for premature or immunocompromised infants. No water needed. Most expensive option.

Safest Option

Common Mistakes & Troubleshooting

Adding powder before water

Always add water first, then powder. Adding powder first results in incorrect concentration — you'll end up with too little water and an over-concentrated feed which can harm your baby's kidneys.

Using water below 70°C

Water below 70°C may not effectively destroy harmful bacteria (like Cronobacter sakazakii) that can be present in powdered formula. WHO recommends water at no less than 70°C for reconstitution.

Using microwave to heat formula

Microwaves heat unevenly, creating dangerous "hot spots" that can scald your baby's mouth and throat. Always warm formula by placing the bottle in warm water or using a bottle warmer.

Adding extra scoops for "extra nutrition"

Over-concentrated formula puts excess strain on the baby's immature kidneys, can cause dehydration, and may lead to dangerous electrolyte imbalances. Always use the exact number of level scoops specified on the tin.

Keeping leftover formula for the next feed

Once a baby has started feeding from a bottle, bacteria from their mouth enter the milk. This contaminated formula can rapidly grow bacteria at room temperature. Always discard any unfinished formula immediately after a feed.

Home Enteral Nutrition (HEN)

Guidelines for patients receiving tube feeding (enteral nutrition) at home via nasogastric (NG), gastrostomy (PEG), or jejunostomy tubes.

Hygiene & Preparation

Wash hands with soap before handling equipment or formula
Clean the feeding bag, syringe, and tube connections daily
Use commercially prepared enteral formulas when possible
Flush feeding tube with 30-50 ml water before and after feeds
Store opened liquid formula in refrigerator; use within 24 hours

Safety Precautions

Elevate head of bed 30-45° during and 30 min after feeding
Check tube placement before each feed (as trained)
Monitor for nausea, vomiting, diarrhea, or abdominal distension
Replace feeding bags and tubing every 24 hours
Contact your healthcare team if signs of tube blockage or infection

Frequently Asked Questions

Can I prepare formula in advance for night feeds?

Yes, but only if you refrigerate the prepared formula immediately at ≤4°C and use it within 24 hours. When needed, rewarm by placing the bottle in warm water (not a microwave). Ideally, prepare each feed fresh. A safer alternative for night feeds is to keep pre-measured water in a thermos and pre-measured powder separately, then mix when needed.

Is bottled mineral water safe for formula?

Bottled water should still be boiled before use. Some mineral waters contain high levels of sodium or sulfate which are not suitable for infants. Use low-mineral bottled water if tap water is not available, and always boil it first to reach 70°C for safe preparation.

How do I know if the formula is at the right temperature?

Drop a small amount on the inside of your wrist. It should feel lukewarm — not hot, not cold. The ideal feeding temperature is approximately 37°C (body temperature). A food thermometer can be used for accuracy.

Can I switch between formula brands?

You may switch brands if needed, but note that the scoop size and water-to-powder ratio may differ between brands. Always read the new label carefully. If your baby has a specific medical condition requiring a specialized formula, consult your pediatrician or dietitian before switching.

When should I seek medical help?

Seek immediate medical attention if your baby shows signs of: persistent vomiting, diarrhea (especially with blood), fever above 38°C, refusal to feed for more than 8 hours, unusual drowsiness, signs of dehydration (dry mouth, no tears, reduced wet nappies), or any allergic reaction (rash, swelling, breathing difficulty).

Quick Reference Checklist

Print this section and keep it near your preparation area

DO ✅

✓ Wash hands thoroughly before preparation

✓ Boil fresh water each time

✓ Cool to 70°C (wait ~30 min after boiling)

✓ Add water first, then powder

✓ Use exact level scoops as directed

✓ Sterilize all equipment before use

✓ Test temperature on inner wrist

✓ Discard unused formula after 2 hours

DON'T ❌

✗ Don't use a microwave to heat formula

✗ Don't re-boil or use old boiled water

✗ Don't add extra scoops for "extra nutrition"

✗ Don't keep leftover formula from a feed

✗ Don't use expired or discolored powder

✗ Don't store powder in the refrigerator

✗ Don't add cereals, sugar, or honey to formula

✗ Don't prop the bottle — always hold your baby

When to Seek Immediate Medical Help

Persistent vomiting or diarrhea

Blood in stool or vomit

High fever (>38°C / 100.4°F)

Refusal to feed for >8 hours

Signs of dehydration

Unusual drowsiness or irritability

Rash, swelling, or hives

Difficulty breathing

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Formula Preparation Guide