What’s the deal with RTF?

by Margot Bertelsmann
Baby Yum Yum - whats the deal with ready to feed formula in south africa
Reading Time: 8 minutes

Novalac Premature ready-to-feed infant milk

Liquid formulas are a thing. When we think of baby formula, most of us imagine those tins with the ring pull opener and the white powdered milk inside. Right? It was only a matter of time before someone figured out you could add the water before you sell it to the customer. That’s right, you premix the formula, stick it in a ready-to-feed (RTF) bottle, and parents don’t have to fuss with scoops and cooled boiled water anymore.

Where can I get liquid formula?

Premixed, or ready-to-drink or ready-to-feed formulas, such as Novalac, Similac, S26, or PreNAN (for premature babies), have been used for five to 10 years, mostly in hospital settings, though some are available in retail.


Alula (Aspen) S26 Gold Stage 1 ready-to-feed infant starter formula

Alula (Aspen) S26 Gold Stage 1 infant starter formula 200ml read to feed and Infacare (Aspen) newborn and follow-on formulas in ready to feed formulations are available at your usual retail stores. They come in a Tetra Pak carton and a plastic bottle, respectively, and both must be decanted into a bottle. It’s worth noting that Novalac’s RTF product, available only in hospitals, comes with an ultra-convenient teat connector so that babies can be fed directly from the product without decanting, thus maintaining sterile conditions.


Says Almerene Mocke, Novalac’s product manager in South Africa: “Novalac has just launched its RTF formula at private hospitals this year. We believe we are following a worldwide trend towards using RTF formula in hospitals. There is just no room for error with a premix. Novalac is only available for babies in hospital and if a doctor prescribes it for out-of-hospital use.”

As with any advances, this one comes with pros and cons, both for the home user as well as babies using RTF formulas in hospital, though the issues may be somewhat different.

The pros of RTF

  • Baby’s food is right where you need it, when you need it, and you can feed on the go or wherever you are: on a flight, visiting friends, or when baby is at work with you.
  • RTF formula has been reconstituted under controlled conditions, which means that no pathogens have been introduced when you’ve added the water or if you have poured the mixture into a bottle that may not have been sterile. Liquid formula is sterile, but powdered formula is not. This is an important issue for fragile NICU babies (more on that later).
  • Avoids user error. With RTF formulas, you can trust that the right quantity has been mixed correctly at the source. If your baby is away from you during the day, you don’t have to leave the mixing-up of powdered formula to day-care staff.


  • It’s expensive. A 200ml bottle of Wyeth S-26 Gold Stage 1 Infant Starter Formula sells for R6.99 at Clicks. In contrast, a 900g tin of Wyeth S-26 Gold Stage 1 powdered formula costs R181 and makes about 34 x 200ml feeds: a total of R5.32 per bottle. Considering you’ll be feeding five or more bottles a day, that difference can quickly add up: R8.38 a day, R250 a month…
  • It doesn’t store as long. Unopened bottles need to be kept in a cool, dry place but don’t need to be refrigerated and can’t be stored as long as their powdered counterparts (always check the packaging for the expiry date). They can be stored as well as served at room temperature. If you do want to heat the bottle, do so by placing the bottle in a pot of warm water and not in the microwave, as these heat unevenly and can cause “hot spots” which can burn your baby.

Remember to shake the bottle just as you would a powdered formula bottle to ensure even distribution of nutrients. If you’ve opened a bottle, you can keep it in the fridge for up to 72 hours before you need to throw it away.

Hang on. What do you mean powdered formula is not sterile?

In 2004, a World Health Organisation study into microbiological hazards in infant formulas found that powdered formulas are not sterile. From the study’s abstract:

“Consistent with the need to provide safe feeding for all infants, the Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO) jointly convened an expert meeting on Enterobacter sakazakii and other microorganisms in powdered infant formula (WHO, Geneva, 2-5 February 2004).

“After reviewing the available scientific information, the expert meeting concluded that intrinsic contamination of powdered infant formula with E. sakazakii and Salmonella has been a cause of infection and illness in infants, including severe disease which can lead to serious developmental sequelae and death. No link has been established between illness and other microorganisms in powdered infant formula, although such a link was considered plausible for other Enterobacteriaceae.

“It is important to note that powdered infant formula meeting current standards is not a sterile product and may occasionally contain pathogens.”

Liquid formula, however, is sterile and so it presents an option if there is a medical reason why your child may need extra precautions and formula feeding. (Don’t panic about using powdered formula though. The risks are low. Just keep preparing it with all the safety precautions you should usually be taking. But if you are worried and have a fragile baby, discuss switching to RTF with your doctor.)


NAN Optipro Stage 1 ready-to-feed formula

The benefits of RTF formulas are especially significant if your baby has to have a hospital stay. Let’s take a moment to empathise with any mother who’s had to leave her baby in NICU. There is some kind of problem with your baby – that’s why you are in hospital, after all. You’re already completely stressed out but, either because you have other children at home, or a job to go to, you cannot be there, or provide expressed breast milk, for baby’s every feed (even though you know that is the best for your baby). It can be hard to trust the milk kitchen in the hospital even though you understand how strictly safety precautions are applied.

It’s no surprise hospitals have started using the premixed versions of baby formula. Doctors have to prescribe formula feeding when it’s necessary in NICU, though. Several private hospitals use RTF formula in these instances.

Verena Bolton, National Coordinator for Netcare Ncelisa Human Milk Banks, says that Netcare hospitals are all working towards Mother and Baby Friendly Initiative (MBFI) accreditation and actively support and promote breastfeeding unless there is a compelling medical reason against this, as breast milk has numerous proven benefits for the healthy development of babies. In addition, Netcare Ncelisa Human Milk Banks were established in a number of their hospitals to enable them to provide stringently regulated donor breast milk for babies whose mothers, for some reason or another, may not be able to provide breast milk.

Bolton adds, “However, we respect the decision of mothers who choose to formula feed. When it comes to premature and other babies being cared for in our neonatal intensive care units, we actively encourage mothers to express milk for their babies, if possible. In the case of formula feeding, mothers can choose between powdered infant formula (PIF) or ready-mixed formula, which is recommended by the World Health Organisation (WHO) for in-hospital use. Ready-mixed formulas are sterile, and do not pose the risk of contamination.

“In accordance with best practice, doctors usually prescribe ready-mixed formula for babies in neonatal ICU where mothers’ own milk or donor milk is not available. However, there is a significant price difference between ready-mix and powdered infant formulas, and medical aid authorisation is required for the use of ready-mixed formulas. There are so many considerations when it comes to formula feeding that it really depends on the specific medical circumstances of the particular mother and baby concerned. In-hospital use of any formula in Netcare hospitals requires a doctor’s prescription, in accordance with our initiative to achieve MBFI accreditation.”

“Liquid formula is sterile and so it presents an option if there is a medical reason why your child may need extra precautions and formula feeding.”

It may even make financial sense for hospitals to use RTF rather than formula. Why? Well, read on for an answer from Nestle, manufacturers of Nan, but first take a deep breath and read the paragraph-long disclaimer which, because of official state policy that promotes breastfeeding as the best possible food for a baby, must precede their comment in order for the company to be able to comment at all.

Ready? Here goes:

“It is important to note that manufacturers of infant formula are prohibited from promoting their infant formula products to the public, but may share factual scientific information regarding their products with healthcare professionals. The information provided to you with regard to Ready-to-drink (RTD) formula is therefore solely intended to provide you with the facts. It should in no way be perceived or repurposed in a promotional manner, to you or any other person. Should anyone require additional information about these products and about the benefits of it, we encourage them to visit their healthcare professional for advice. Nestlé protects and promotes breastfeeding and believes that suitable infant formula solutions should be used only in absence of breastfeeding on advice of a healthcare professional.”

And now on to the comment.

Nestle goes on to say: “RTD formula is a growing tendency in the world for convenience and safety reasons. For example, there is no need for additional preparation, no requirement for additional bottles, no need for milk kitchens within hospitals, which makes it less labour intensive. Furthermore, as the RTD products are in a ‘closed system’ it reduces the risk of contamination of feeds, making it safer to use in situations where safety and hygiene can be a concern. As many other infant formula manufacturers, Nestlé also invested in RTD formula solutions. RTD formulae are similar to powdered infant formulae in that it caters for healthy full-term infants or infants with special nutritional needs i.e. premature or low-birthweight babies. Nestlé does not sell RTD solutions in retail in South Africa and only provides to hospitals.”

The bit that made us prick up our ears is the part about “no need for milk kitchens within hospitals”. If RTF formulas were offered as a matter of policy in hospitals (once a doctor had decided that formula feeding was appropriate for a particular baby), then the extra cost of the ready-mix might be offset by the ability for hospitals no longer to operate milk kitchens.

But Netcare’s Verena Bolton dismisses this, saying hospitals will always need milk kitchens for the following reasons: “When mothers bring their own expressed breast milk for their babies, it needs to be stored and decanted in accordance with the baby’s requirements, and so you need a temperature-controlled environment where aseptic management of mother’s own milk can be performed.

“Very low birthweight neonates may take only 0.5ml or 1ml every three hours, and when the decision has been made to not use breast milk, the ready-to-mix feed is opened and decanted. It is not an option to open a 30 or 45ml bottle of ready mix at the time, feed the baby and chuck out the rest. The cost is simply prohibitive. Thus, even ready-mixed formulas are decanted for a 24-hour period, and this happens under aseptic conditions in a milk kitchen.

“Thirdly, when a mother can’t provide her baby with her own milk, donor milk is used, defrosted, decanted and prepared for the baby, and this happens in a milk kitchen.

“Lastly, babies with short bowel syndrome require very specialised feeds, with additives to increase the caloric or protein or lipid density of the formula they are receiving. Currently there are no ready-mix feeds appropriate for these babies, and specific powdered formulas are used. These require a milk kitchen for their aseptic preparation.”

Who knows what the formula landscape will look like in 50 years? What we do know is that RTF formulations are at least as safe as and probably safer than powdered formulas. We predict that their use, especially for follow-on milks and in the retail space, is set to grow.

Disclaimer: This is not a sponsored post and is based on personal experience and personal brand preference of the content author. BabyYumYum reserves the right to its opinions and fully supports the notion of promotion that breast is best in line with the World Health Organisation (WHO) infant feeding guidelines. Breast milk is the best food for infants. Good maternal nutrition is essential to prepare and maintain breastfeeding. If breastfeeding is not applied, an infant formula may be used according to the advice of health professionals. Preparation and storage of any infant formula should be performed as directed on the tin in order not to pose any health hazards.

Also read:

Breaking the silence around formula feeding
What’s in my infant’s formula?

Related Articles