The current situation of rising energy prices is a problem for industries across all sectors. Not only the increase in price itself but also the difficulty in forecasting these prices in the medium term. This directly influences process costs and generally, the additional cost cannot be directly passed on to the final product price. Selecting technologies is key in this process. We share a specific case of energy cost reduction in the dehydration processes of products through spray drying technology.
When selecting technologies and designing industrial equipment and facilities to manufacture a specific product, estimates about the prices of each type of energy, manufacturing materials, raw materials, and land are considered, and based on these considerations, certain technologies are chosen. As sometimes happens with household appliances or transportation means, there are alternatives, some equipment is more economical, others are more expensive but consume less, or are more autonomous, take up less space, etc.
From our experience in the stabilization processes of microorganisms, we tell you an example of dehydration technology with lower energy cost for dry powder products intended for animal feed or for agricultural applications.
Spray drying as an alternative to freeze-drying
It is the case of spray drying technology as an alternative to freeze-drying to stabilize microorganisms as a dry powder product. As microorganisms are sensitive, when their viability is intended to be maintained, freeze-drying is traditionally used, since it is a dehydration technology that does not require temperature.
In the case of probiotic microorganisms for food, nutritional supplements, bacteria, and yeasts, starter cultures for fermentation, it is generally the first option to consider. But there are increasingly more applications where the final product price is very relevant for the viability of the product, such as probiotic microorganisms and microalgae for animal feed or microorganisms for agricultural applications as biocontrol agents, so it is necessary to consider other possible lower energy cost technologies.
The 5 advantages of spray drying for the dehydration of products
The spray drying technology for the stabilization of microorganisms while maintaining their viability and stability over time presents several advantages:
- Lower energy consumption: the first of them is a lower energy consumption compared to freeze-drying. The freeze-drying process is about up to six times more expensive per Kg of water removed than the spray drying process.
- Needs more economical industrial equipment: The industrial equipment required for spray drying is also cheaper than freeze-drying equipment, for the same production volume.
- Produces an easy-to-handle powder product: Additionally, the product obtained is a powder, easy to handle, fluid, and easy to dose, compared to the “cakes” that are generally obtained by freeze-drying, which require extra handling.
- Allows handling of large production volumes: On the other hand, spray drying is a continuous process, as opposed to freeze-drying which is usually done discontinuously, in batch processes. Being a continuous process, it can handle large production volumes, coupled with a biotechnological process of microorganism cultivation.
- Enables improved properties to the final product: Finally, in the spray drying process itself, it can be combined with the microencapsulation of the microorganism, which allows for improved properties, such as:
- Greater protection against temperature or oxidation
- Controlled release under specific conditions (for example, pH for release in the colon)
- A reduction in odor and taste impact, or greater stability over time.
Selection of process variables, a critical aspect in the initial stages
Conversely, the spray drying process remains a thermal process, which could potentially damage the cells and cause loss of viability, so the selection of process variables is a critical aspect in the initial stages of development. Additionally, spray drying has many process variables, with very interconnected effects. This makes the initial adjustment of the process complex. However, once these variables are defined, the process is scalable to industrial levels at large production volumes.
Development of stabilization processes of microorganisms by spray drying from laboratory scale to pilot scale
At AINIA, we have experience and equipment for the development of these processes of stabilization of microorganisms by spray drying from laboratory scale to pilot scale and production. In addition to the development of the process, we offer a service of production of batches under sanitary registration of intermediate product (spanish).
Furthermore, spray drying is not the only microencapsulation technique; there are many technologies to microencapsulate. At AINIA, we work on the development of microencapsulation processes with different techniques. Here is a link for more information about technologies and microencapsulation processes that we work with at AINIA.
