Steam is used in food processing for a variety of reasons, from preparing product to cleaning equipment. Common uses of steam in food and beverage facilities include:
• Blanching product • Rehydrating product
• Sterilizing equipment • Steam-in-Place (SIP) to clean pipes
But not all steam is created equal.
The 3 Types of Steam in Food Processing
Steam used by food processors falls into three categories:
Plant steam: This type of steam is typically produced by a boiler
and can be used in applications that do not involve contact with
food or with surfaces that contact food.
Culinary steam: This is steam used for direct injection into product,
or to clean or sterilize product contact surfaces. Culinary steam
typically contains additives that prevent corrosion and scaling within
boilers, so it is often filtered before coming into contact with food
product. Any additives in culinary steam must meet all applicable
FDA and USDA requirements for human consumption.
Pure steam: Pure steam does not contain additives and is created
by heating untreated water that is stored separately. Pure steam
is often used to produce organic products that restrict usage of
chemicals and additives.
It’s pretty clear when and how you should use ordinary plant
steam, but when it comes to food contact, what steam should
you use: culinary or pure? The majority of steam used in the
food industry is culinary steam, but there are instances in which
pure steam is preferred/required. Let’s examine the benefits and
considerations of each.
Culinary Steam vs. Pure Steam
Culinary steam is the standard in most food plants. It is food-safe and can be used to blanch, rehydrate and sterilize food
product. More than likely, culinary steam is the appropriate choice
for your facility, but there are some considerations to keep in mind.
Benefits of Culinary Steam
More economical long-term: Compared to producing pure
steam, culinary steam requires less energy and water, meaning
lower utility bills in the long run.
Less costly up front: Opting for culinary steam doesn’t require
initial investment in a steam generator, saving you money up front.
Considerations with Culinary Steam
Not as hygienic: While culinary steam is food-safe, it’s simply not
as hygienic as pure steam that doesn’t contain chemicals/additives.
Ongoing cost and maintenance: Since culinary steam is made
from water containing additives, the steam is run through strainers
and filters to remove as many impurities as possible before it is
introduced to the product. These filters must be changed on a
regular schedule; if neglected, an inspector can judge your steam
quality below the requirements to be classified as culinary steam.
Pure steam is the most food-safe option available. Typically,
processors who use pure steam are doing so to meet organic food
standards. There are two ways to produce pure steam:
Steam heating coil: This method involves utilizing steam from
the plant boiler to heat coils that in turn heat the water they are
submerged in. This container of water is heated until it changes
phases and creates steam. Since the container is exposed, not all
of the steam can be contained, making this method somewhat
inefficient. Plus, excess steam that escapes will eventually raise
the humidity level in the building, which can create other issues
like mold or bacterial growth and/or equipment rusting.
Steam generator: This method also involves heating a container
with coils, but the water is contained in a sealed, pressurized
tank. This is more efficient than a steam heating coil since the
steam is contained and can’t escape.
Benefits of Pure Steam
Increased food safety: Pure steam improves the hygienic
quality of products and is food-safe when it comes to blanching
and other steam-related processes. There is no risk of chemical
contamination because there are no additives.
Meet organic standards: The majority of food processors that
utilize pure steam do so to meet certain standards in order to
label their products as “organic.” There are various ways to define
and label food as organic, and each definition comes with its own
standards. Since most organic foods require no introduction of
chemicals or additives in processing, this almost always means
pure steam must be used.
Considerations with Pure Steam
Less efficient: Generating pure steam requires additional water
and more electricity to heat the coils and power the process. This
means increased usage and higher utility costs long-term.
More expensive up front: Steam generators are a big investment.
While traditional culinary systems come with startup costs, it’s
usually not as expensive as opting for a pure steam system.
Choosing pure steam it isn’t an “all-or-nothing” decision. A facility
can have several blanchers but only elect for a few to be equipped
with pure steam capabilities. This allows plant owners to have
flexibility in deciding how much money to invest based on their
needs and organic SKU percentage.
How much pure steam capability you need really depends on
how much organic product you produce. An experienced partner
can help you make the best decision and calculate the right balance
for your facility’s needs.
Plant Steam vs. Culinary Steam vs. Pure Steam:
What Food Manufacturers Need to Know
By Sam Simkowski, Mechanical Engineer, Stellar