Our Process

Low-Temperature Vat Pasteurization

Hartzler Family Dairy uses Low-Temperature Vat Pasteurization. This ensures our milk retains a majority of it's enzymes, which are crucial for proper digestion and good health. 

Pasteurization of commercially-sold milk is required by the U.S. Food and Drug Administration to ensure that harmful bacteria in milk is eliminated. Standard pasteurization methods utilize high-heat, high-volume methods that unfortunately kill beneficial enzymes as well as bacteria. Some milk is even ultra-pasteurized to the point that it can be stored without being refrigerated. Some in the dairy and health industries refer to ultra-pasteurized milk as "dead milk" because everything harmful and beneficial has been killed. 

Hartzler Family Dairy's Low-Temperature Vat Pasteurization method allows us to heat our milk at a lower temperature for a longer period of time, eliminating harmful micro-organisms but leaving valuable enzymes untouched. 

During our pasteurization process, the milk is heated in our vats to a temperature of 145 degrees F (63 degrees C). It is held at this constant temperature for 30 minutes. 


While most milk undergoes homogenization, ours does not. 

Homogenization was developed simply to give milk a balanced consistency, eliminating the need to shake it before drinking. Milk in it's natural state has a cream layer that floats to the top.

Anyone who grew up on a farm, or before homogenization was common, will tell you that the cream gives milk a clean, full-bodied flavor and is the most desirable part! We tend to agree.

But beyond taste, however, we choose not to homogenize because it changes the molecular structure of milk, which has unhealthy consequences. In particular, it prevents the delivery of important nutrients to the body. 

Glass Bottles

While some folks love the nostalgia of our glass bottles and seeing the cream line at the top, there are actually some very important reasons why our milk is sold in glass bottles. 

The first is that it prevents the absorption of unwanted chemicals from seeping into your milk. Most plastic bottles and jugs leak measurable amounts of chemicals into the liquid they contain. 

Second, the thick glass bottles we use also keep the milk cooler, adding to it's freshness.

And last, but by no means least, our philosophy of doing things "as nature intended" also applies to the way we treat the earth. Instead of further adding to landfills, we collect, sanitize and reuse our 1/2 gallon glass bottles. You only need to return them to any location that sells Hartzler milk, and you'll receive a deposit and the bottles will be picked up by our drivers to take back to our plant and be reused.