High lipase in breastmilk: What it is & how to prevent that soapy taste

Breastfeeding often presents us with issues, and one of the lesser-known challenges some parents face is high lipase in breastmilk. If you've ever expressed and stored your milk only to find that it smells or tastes soapy, metallic, or even sour, you might be dealing with this issue.

The good news? High lipase milk is perfectly safe for your baby, and with a few simple adjustments, you can prevent it from developing an off-putting taste.

As a paediatric nurse, IBCLC lactation consultant, and antenatal educator in Dubai, I’ve supported countless breastfeeding parents, helping them navigate the unexpected hurdles of milk supply, storage, and feeding. If you’re worried about your baby refusing expressed milk, this guide will help you understand what’s happening and what to do about it.

What is high lipase in breastmilk?

Lipase is a natural enzyme found in all breastmilk. Its job is to break down fats, making them easier for your baby to digest and absorb. It’s one of the reasons why breastmilk is so nutrient-rich and beneficial for your baby's gut health.

However, some parents produce higher-than-normal levels of lipase, which causes the fat to break down more quickly. While this doesn’t impact fresh milk, stored breastmilk can develop a soapy, metallic, or sour taste over time, especially when refrigerated or frozen.

Is high lipase breastmilk safe for babies?

Yes! High lipase milk is completely safe for babies to drink. However, some babies are sensitive to changes in taste and may refuse the milk if the flavour has altered too much.

If your baby doesn’t mind the taste, you don’t need to do anything. The milk still has all its nutritional benefits.

If your baby refuses the milk, you’ll need to take steps to prevent the taste from changing (see below).

How to test for high lipase in your breastmilk

Before making any changes, you’ll want to confirm whether your milk is affected by high lipase.

Here’s how to test your milk:
Express some fresh breastmilk and taste/smell it immediately.
Store it in the fridge for a few hours to 24 hours.
Taste/smell it again.
If it smells/tastes soapy or metallic (but was fine when fresh), you likely have high lipase.

If your milk doesn’t change in taste over 24 hours but becomes off-putting after freezing, then freezing is accelerating the breakdown process.

How to prevent stored breastmilk from tasting soapy or sour:

Scald your milk before storing it.

Scalding stops the enzyme activity in the milk before it has a chance to break down fats.

How to Scald Breastmilk:
Heat your freshly expressed milk in a clean pan over low heat.
Warm it until you see tiny bubbles forming around the edges (around 77°C / 170°F) – do NOT let it boil.
Remove from heat and cool it quickly before refrigerating or freezing.

This process stops the lipase from breaking down fats, preserving the milk’s original taste and is best for parents who want to store milk for later without worrying about taste changes.

Use fresh milk whenever possible

If you know your baby dislikes high-lipase milk, try to prioritise fresh milk over frozen when feeding.

Express milk just before a feed.
Store it in the fridge and use it within 24 hours to minimise taste changes. This is best for parents who are expressing regularly but don’t need to freeze milk long-term.

Mix high-lipase milk with fresh milk

If your frozen milk tastes slightly off but your baby refuses to drink it, try mixing half high-lipase milk with half fresh breastmilk. This can neutralise the taste enough for your baby to accept it. This works best for parents who don’t want to waste stored milk but need a workaround for picky babies.

Add breastmilk to solids (for weaning babies)

If your baby is starting solids, you can use high-lipase milk in purees, porridge, or mashed foods. The flavour blends in, making it less noticeable.

Common myths about high lipase breastmilk

"High lipase means something is wrong with my milk." - No. Your breastmilk is still perfectly safe and nutritious. Lipase is a normal enzyme that benefits digestion.

"I have to throw away all my frozen milk." - Not necessarily. Try mixing it with fresh milk or using it in solids before discarding it.

"Scalding milk removes all the nutrients." - Scalding does slightly reduce some immune-boosting properties, but your milk will still be far more beneficial than formula. If your baby won’t drink high-lipase milk, scalding is a great alternative to wasting your supply.

If you’ve discovered your milk has a soapy or sour taste, don’t panic. High lipase milk is still nutritious and safe. By scalding your milk, using fresh milk when possible, or mixing stored milk with fresh, you can ensure your baby gets the benefits of breastmilk without any issues.

Need breastfeeding support? As an experienced IBCLC lactation consultant in Dubai, I offer one-on-one consultations, online breastfeeding support, and guidance for expressing & storing breastmilk.

DM me or book a consultation today if you need any advice on any aspect of breastfeeding.

‍

‍