Our Story

Hello! I am Mary-Thea Brosnan, owner of Kerry Kefir

Mary-Thea Brosnan | Kerry Kefir | Intro

I love the great outdoors, something I only discovered in my late 20’s. I love the mountains, I love the sea and I love everything about nature. I also love my dogs, Ben and Obie. Two beautiful golden retrievers with completely opposite personalities.

After 14 years living in Dublin, I moved home to Castleisland in Co. Kerry in October 2018 to start Kerry Kefir. I continued to work part-time as an Optometrist (I have a BSc in Optometry) before going full-time with Kerry Kefir in January 2020. I started the business in my parents’ kitchen but I soon moved to a converted truck container behind the house. For the first year, I sold directly to customers in Castleisland but Kerry Kefir is now stocked in SuperValu stores and independent retailers around Kerry.

Having suffered from digestive issues for years, I was prescribed tablets to be taken before every meal for the rest of my life.

I spent years looking to help my symptoms through diet until a nutritionist advocated milk kefir, a fermented milk beverage packed full of beneficial bacteria and yeast for your gut health.

I sourced kefir grains and started making it myself. Within a week, the kefir milk had made a huge difference to my symptoms. I couldn’t believe it! 

I noticed that none of the milk kefirs on the market were made in the traditional way using kefir grains but were instead using powdered, lab-manufactured cultures. So I decided to create a premium product using the living organisms to produce the most natural form of milk kefir as it was traditionally made.

Banna Beach Sunset | Kerry Kefir

Why Choose Us

Traditional Kefir Grains | Kerry Kefir

Traditional Kefir Grains

We are the only milk kefir on the Irish market making milk kefir the traditional way, by using live kefir grains

Handmade batches | Kerry Kefir

Handmade batches

Every single batch of Kerry Kefir is lovingly handmade, so that you can enjoy your traditional kefir straight from our kitchen to yours

Environmentally Friendly | Kerry Kefir

Environmentally Friendly

Kerry Kefir is bottled in glass bottles. The bottles can be returned to us so we can re-use them multiple times

Our Process

Our Awards

 In July 2019, Kerry Kefir was awarded the “One to Watch” in the Connect Kerry Women in Business Awards.

In October 2020, Kerry Kefir won Gold in the Blas na hEireann Irish Food Awards, and we were also awarded the Best Start Up for 2020

Reach Us


Mary-Thea Brosnan
Tralee Road,
Co. Kerry




M-F:  10am – 3pm
S-S: 9am – 2pm

Get In Touch