Top 3 reasons why grass fed raw milk changes in flavor and consistency.
posted on
August 15, 2025
Have you ever noticed that the flavor and consistency of our raw milk varies from week to week and especially season to season? This is 100% normal!
You see, when you raise animals naturally on pasture (and especially when they're 100% grass fed like our cows and buffalos), the milk changes.
This is starkly different from pasteurized milk you'd find in stores, which is usually from grain fed cows in feedlots. With that level of unnatural control, the milk can be consistent (or maybe I should call it boring).
Here are the top 3 reasons grass fed raw milk varies:
1- Butterfat changes with the seasons. It's highest in the colder months.
From the anecdotal experience of myself and our farmers, butterfat is highest in the spring. That's when milk is the creamiest, the most yellow, and the most flavorful (after all, fat holds the color and the flavor). That's when you get a hefty creamline in your jug of milk after sitting in the fridge for a few days. But then...
I found an interesting study on this. It's from 1931, before dairy farming got seriously messed up. It tracked hundreds of cows over many years. The researchers found that butterfat and outdoor temperature have an inverse relationship. And they found that it didn't really matter when the cows give birth and the age of the cow. Fascinating!
In short, the higher the temp outside, the less butterfat. The lower the temp outside, the more butterfat. Check it out:
Another interesting note on the graph is they found that Jersey cows produce milk with the highest butterfat. We noticed this, too, and it's why Aaron's herds are 80% Jersey and 20% Jersey crosses. That's why our milk is so darn creamy!
It does make me wonder why, anecdotally, we feel butterfat is highest in spring. Maybe it's because our cows produce the most milk in the spring and least in the winter...? We feel like we're swimming in butterfat in the spring. We make sooo much butter at that time of year.
2- Flavor changes with the feed. When the forage, the weather, and the seasons change, so does the flavor.
When cows are outside on pasture, eating a diversity of plants, the flavor of the milk they produce is more robust. Mostly this is a good thing. In my opinion, our pastured milk is more flavorful and tastes better than conventional grain-fed feedlot milk. But, sometimes this can kick us in the butt. For example, when a cow finds a little patch of onion grass, that can create an odd flavor in the milk.
The weather affects what the cows are grazing on, too. For example, when we're in a drought, the grass doesn't grow as voraciously. It's has less moisture and protein and isn't as fully developed. That can change the flavor of the milk.
And finally, there are, of course, the seasons. When the cows are eating fresh pasture in the warmer months, the milk will have a different flavor than when they're eating dry pasture (AKA hay) in the colder months.
It's hard to predict what the final flavor will be. But, I sure do love tasting the differences in milk throughout the year!
3- How long it lasts changes with cleanliness. Clean milk lasts longer!
Milk safety is a top priority here at Miller's. Our strict milk safety standards go beyond what's required for a raw milk permit in Pennsylvania. We test every batch on site for general bacteria counts. Not many raw milk farmers do that, but we sure hope more hop on board!
Since we test every batch, we're able to keep a close eye on how well the team is cleaning. Even a small thing like a cat licking equipment in the barn, a tiny hairline crack somewhere, or water not being hot enough can make a big difference.
Because of our constant monitoring, we're pretty confident in saying that our milk is the cleanest around. There's no manure in our milk!
And because of this, our milk lasts longer than most. It's raw milk and will sour (no way to prevent that). But, it should last at least 2 weeks after you receive it before it becomes too sour to palate.
Do you value milk consistency over naturalness? Have you noticed changes in our raw milk over time? What about milk makes it "the best" for you?
I'd love to hear from you. Comment below to share your thoughts with our community (no account requred). Or, contact us to keep it private 😊
PS: Did you know that we make our fresh raw cow dairy in house? That's right. Our team does it in our creamery! Our goat and buffalo farmers make their own fresh raw dairy in house, too.
-----
Sources
