Probiotics, Packaging & the Path Through Your Gut: A Practitioner’s Perspective

7 Aug

It started, as it often does, with an email from a client.

“Hi Chantel, I’ve just received my shelf-stable probiotics in the post. The box was warm - they must have been sitting in the sun for a while. Are they still effective? And while we’re at it, do I actually need enteric-coated probiotics? Because the companies who sell them say everything else gets destroyed by stomach acid. And what about probiotics from food - wouldn’t those be destroyed too?”

It’s the kind of question I love because it blends real-world concern with the need for clinical clarity. And it’s one I know many practitioners have heard in one form or another.

So, let’s unpack it together.

Why Delivery Method Matters

Picture the stomach as an acid bath (pH often <3.0) - designed to kill unwelcome microbes. Many probiotic strains - like Bifidobacterium spp. - are highly vulnerable without protection. Hardier strains, like Saccharomyces boulardii or Lactobacillus rhamnosus GG, manage better on their own.

That’s where delivery systems can make a difference. Enteric coating, microencapsulation, or delayed-release capsules are not decorative, they’re shields.

But! The evidence for these methods is still in the preliminary stages so don’t get overly excites just yet!

The Journey of a Probiotic, here’s how it works…

Imagine a probiotic capsule as a little life raft full of beneficial microbes.
Its mission? To sail through the acidic seas of the stomach, survive the churning currents of the small intestine, and finally dock safely in the colon, ready to get to work.

The stomach is no gentle pond. It’s an acidic gauntlet, designed to kill off pathogens in food - and it can be just as unkind to delicate probiotic strains.

Non-enteric coated probiotics are like tiny sailors in rowboats. Some are hardy and make it through. Others, not so much.
Enteric-coated capsules are like submarines - they glide right past the acidic surface waters and surface later in calmer territory.
Microencapsulated probiotics are more like divers in protective wetsuits - still exposed to the elements but better insulated against harm.
Fermented foods? They’re less a fleet and more a flotilla - a mix of microbes, nutrients, and metabolites arriving in the gut ecosystem together.

What the Evidence Tells Us

Researchers have tested this voyage in both the lab and simulated GI environments:

Enteric-coated capsules generally show higher survival rates for sensitive strains in simulated gastric conditions - losing less than 1 log CFU compared to much greater losses in non-coated formats (Millette et al., 2013).
Kailasapathy & Chin (2000) demonstrated that microencapsulating L. acidophilus and B. lactis (in alginate or chitosan) significantly improved survival under simulated gastric juice.
Cook et al. (2012) used dynamic gut models to show that enteric-coated L. plantarum delivered 100–1000× more viable cells into the intestine than uncoated forms (improving passage survival)
Microencapsulation techniques (alginate, chitosan, etc.) also protect viability, particularly in challenging environments like high acidity or bile exposure, but large-scale clinical data is still catching up.
Some strains, like Saccharomyces boulardii and Lactobacillus rhamnosus GG, are naturally more resilient, even without special coating.

What Human Studies Reveal

Clinically, the data is more limited:

Human studies show that protective delivery systems such as enteric coating and microencapsulation can improve the survival of acid-sensitive probiotic strains through gastric transit (Marteau et al., 1997; Ouwehand et al., 2000). Whether this consistently translates into better symptom relief is less certain, as few trials directly compare coated versus uncoated forms in people. For now, coating appears most useful when working with fragile strains or when targeting probiotic activity in the small intestine.

And What About Probiotics in Food?

Here’s where the “destroyed by stomach acid” argument oversimplifies things.

Traditional cultures have been consuming probiotic-rich foods for centuries, kefir, sauerkraut, kimchi, miso, without worrying about encapsulation. These foods don’t deliver a precise CFU count, but they do:

Deliver live microbes within a protective food matrix that can buffer stomach acid.
Provide prebiotic fibres and metabolites that support survival and colonisation.
Introduce microbial diversity in ways that capsules can’t replicate.

So no, stomach acid doesn’t simply wipe them out. The delivery system is different, but not inherently less valuable.

Shelf-Stable Probiotics & the “Warm Parcel” Question

Now, about that box left sitting in the sun.

Shelf-stable probiotics are formulated with hardy strains and stabilisers to tolerate normal fluctuations in temperature during shipping. In most cases, a few hours in a warm delivery van or on a sunny porch won’t destroy their efficacy.

But - and here’s where practitioner caution comes in - prolonged exposure to high heat (think days, not hours) can reduce viability. Some companies conduct accelerated stability testing to demonstrate survival under stress, but those details are often tucked away in technical data sheets.

Practical tip:

If a parcel arrives hot, open it, check the inner blister or bottle - if the product looks, smells, or tastes different, or if the company confirms heat instability for that strain, request a replacement.
For sensitive therapeutic cases, I err on the side of caution and use cold-shipped or refrigerated products when the formulation demands it.

Clinical Take-Homes for Practitioners

When advising clients, consider both strain specificity and delivery method:

Enteric coating: Best for sensitive strains or compromised gastric environments.
Microencapsulation: Useful where stability is a concern or GI conditions are challenging.
Robust strains: Many survive well without protection - especially S. boulardii, L. rhamnosus GG, and spore-formers.
Fermented foods: Encourage as a daily ecosystem support, not a replacement for targeted therapy.
Storage matters: Respect manufacturer guidelines - “shelf-stable” doesn’t mean “heat-proof forever”.

The Bigger Picture

The probiotic conversation isn’t just about capsules and coatings, it’s about context.

A probiotic isn’t a magic bullet; it’s one tool in a much wider gut-health strategy. Strains, delivery method, diet, and the client’s microbiome terrain all influence whether that tiny life raft makes it to shore.

And when your client asks, “But is it working?”, the most honest answer is - it depends on more than just the capsule. It depends on the match between the right strain, in the right form, for the right person, and the right job at the right time.