Why are We Steaming Our Leafy Greens?

Whether leafy greens, like spinach, basil, salad and parsley, are conventionally grown or organically grown, they may be subject to microbial exposure. Often, contamination can be caused by something as simple as a bird flying over a field where crops are grown.

While drying or dehydration prevents the growth of many microbes as well as yeast and mold, it does not combat all potential contaminants, and dried herbs and vegetables can still be at a similar risk as fresh produce, for contamination with pathogens like Salmonella.

At The Honest Kitchen, we have always used a gentle but effective steaming technique as a ‘kill step’ to eliminate pathogens in our meats and eggs. Given the potential risk of contaminants in human-grade leafy greens, we have decided to add an additional safety measure for our dehydrated ‘leafy greens’ as well.

The point of a kill step is to eliminate harmful pathogens with minimal processing, to leave as much of the natural nutrition intact without actually ‘cooking’ the product before it is dried.

Steam Sterilization is a process of treating dried herbs and leafy greens with continuous steam at a temperature range of 165°F to 180°F, to reduce microbial pathogens, depending on the type of dried ingredient being treated. It leaves behind no toxic residue, is a more eco-friendly solution because it uses less energy and no chemicals. It also results in a healthier finished product. Steam sterilization is also considered to be a truly organic process.

How do we know steaming is effective?

A validation process is used to demonstrate a ‘five log reduction’ in specific pathogens, and that is used to help determine what temperature is needed for each ingredient, in order to be effective.

As foodies ourselves, we have a very strong focus on the balance between nutritional integrity and the safety of our finished products. We put a lot of care and attention into determining the best steps for producing our products and consider all the pros and cons of the various production and testing options that are available. We feel that this gentle steaming process will help ensure the safety of our dried herbs and leafy greens, while still be gentle and respecting the delicate colors and nutrients that Mother Nature provides.

What are the other benefits of steam sterilization?

  • There is a minimal effect on the flavor or aroma
  • Less than 5-8% of the oil content is lost during the process
  • The delicate structure of cut leafy herbs and botanicals is maintained
  • There is no drastic change of color, even in fragile ingredients
  • There is no increase in the moisture content of the finished products

Many culinary and medicinal dried herbs, spices, teas and botanicals undergo steam sterilization as an important safety step to eliminate pathogens. Steam sterilization is considered a ‘clean’ option for eliminating pathogens, even on delicate and certified organic ingredients.