Raw dog food is not always frozen. It comes in other more convenient forms like dehydrated, freeze-dried and "air-dried." Hmm...isn't air drying dehydrating? All of these manufacturing processes remove water from food to preserve or reduce loss of certain nutritional properties. Ok, basic science but let's look into it more......(reader beware this is a ridiculously long post so grab a cup of coffee or tea!)
Definitions As a starting point, I found several resources on-line to differentiate these terms in the context of human food science and technology (see below).
- Drying is traditionally used for thermal removal of water to about 15-20% moisture at ambient (atmospheric) air conditions (1).
- Dehydration is traditionally sued for drying foods down to about 2-5% moisture (1).
- Freeze drying is a slow and expensive process. The frozen material is subjected to a pressure below the triple point (at zero degrees C, pressure: 610 Pa) and heated to cause ice sublimation to vapor (gas phase). This method is used for high-quality dried products, which contain heat-sensitive components such as vitamins, antibiotics and microbial culture. The virtual absence of air and low temperature prevents deterioration due to oxidation or chemical modification of the product. It also gives very porous products, which results in high rehydration rates. Rehydration is a process of moistening dry material (2).
- High Pressure Processing (HPP) is a method of food processing where food is subjected to elevated pressures (up to 87,000 pounds per square inch or approximately 6,000 atmospheres), with or without the addition of heat, to achieve microbial inactivation or to alter the food attributes in order to achieve consumer-desired qualities. Pressure inactivates most vegeta-tive bacteria at pressures above 60,000 pounds per square inch. HPP retains food quality, maintains shelf life. The process is also known as high hydrostatic pressure processing (HHP) and ultra high-pressure processing (UHP) (3).
Keep in mind dog food companies will use marketing terms like “low” or “gentle” heat to describe their manufacturing processes and to make their products appear superior to traditional processes or other brands. Think about this: we use heat to cook our fresh foods, we eat heat and cold processed foods, and human food manufacturers do not claim or make a big deal that their processes preserve vital nutrients, vitamins and minerals, etc. [the way dog food companies do]. This is a perfect example of balancing the information you read on dog food labels to reality. By doing your homework (or reading my blog!), you decide what to do with the information and prioritize what is most important to you.
Reading between the lines Here are excerpts from three companies describing their processes:
“Whole foods minus water. The Honest Kitchen’s foods are made using a technique called dehydration. This is a slow, gentle method of very minimally processing the food, which removes the moisture from our raw ingredients. Dehydration takes several hours, and uses warm air to ‘blow away’ the moisture (mostly at temperatures below 104 degrees, except for our meats and eggs, which are dehydrated at over 120 degrees in order to kill any pathogens that may be present, and make the food completely safe even for an immune compromised pet). Dehydration is much gentler than canning or extrusion, which generally involve very high heat and pressure, and are used to manufacture most types of pet food including most kibbled diets. Canning and extrusion involve such high temperatures, that many of the natural nutrients in the raw ingredients are actually destroyed, meaning the manufacturer must replace them with dozens of artificial vitamins and minerals, in order to make the finished product meet the AAFCO nutrient profiles.” - from The Honest Kitchen website
“Hydrostatic High Pressure (HHP) is a technology that ‘puts the squeeze’ on food pathogens without cooking out vital nutrients or changing the natural taste. It’s based on the discovery that bacteria cannot survive at pressures five times those found at the deepest sea level. To date, HHP is the only scientifically recognized pasteurization process that does not use heat or irradiation to accomplish this. But that’s just one of the steps we take to protect the health of your family and pet...When you freeze-dry a product, it starts out frozen. The ice crystals turn directly into water vapor, skipping the liquid stage. Through this process, practically all the nutritional value of the raw meat and produce is retained. In contrast, dehydrating a product requires high temperatures to evaporate the water. Since dehydrating is similar to cooking, many of the vital nutrients are lost.” - from Stella & Chewy’s website
"Raw without the thaw - the raw ingredients are gently air-dried to maintain the highest nutritional integrity. Available in air-dried pouches. The gentle air-drying process delivers a high quality diet while maintaining the nutritional integrity of the natural raw materials. Air-drying is a sterile and safe food processing method, carried out under controlled conditions. Food is best used within 30 days after opening and can be stored in the freezer. - from ZiwiPeak website
Just a brief list of brands for each type of raw food:
DEHYDRATED/AIR-DRIED
- The Honest Kitchen
- ZiwiPeak
- SOJOS by Sojourner Farms
- Dr. Harvey's
- Happy Dog
- Nature's Variety
- Stella & Chewy's
- Grandma Lucy's
Show & Tell Don't know about you but I like to touch, smell and inspect my dogs' food especially if I want to try new products. So I'm saving you the trouble....below are three raw food products by The Honest Kitchen (dehydrated), Stella & Chewy's (freeze-dried) and ZiwiPeak (air-dried). They are considered "complete & balance" by AAFCO guidelines but depending on your dog's condition, additional supplements may be a good idea.
The Honest Kitchen
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| Free 1 oz. sample. Powder form + water turns into soup and later into oatmeal like texture. |
Stella & Chewy's
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| 6 oz. bag (12 patties) $10.99. Serve as is or rehydrate w/ 1/4 cup water per patty |
ZiwiPeak
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| Another free sample. Texture is like bits of chewy jerky. |
Bottom Line These dog foods (and the list of brands) presented here are all excellent types of raw food products. Clearly, all three companies are doing something different than the mainstream. They are making better dog food! Period. Sticker shock will keep typical dog owners away from these foods. Who is feeding this stuff to their dogs? I think there are two types of people: 1) people who want only the absolute best for their dog and willing to pay top dollar and 2) people who are cognizant, who want to add variety to their dog's diet, rotate different forms of dog food but are cost-conscious. Me? I'm #2. Stella & Chewy's is marketed for small breed dogs under 30 pounds. S&C's freeze-dried patties are special, high-value treats or toppers for my BCs. The Honest Kitchen mixes are expensive so I get the free 1 oz. samples for toppers (there are also handy 4 oz. travel sizes, too). THK may give some dogs bulky poop. Also, there are high mark-ups on a 4 lb. box of Embark; prices ranges from $35.95 to $53.99; THK sells it for $43.50.
Resources (1) Handbook of Food Processing Equipment by Saravacos & Kostaropoulos; (2) Handbook of Food Preservation by Rahman; (3) High Pressure Processing Fact Sheet for Food Processors by Ohio State University.
Disclaimer When I blog about dog foods, supplements, treats, etc., my sole intent is to share information & experiences based on my own research and condition of my dogs. It may or may not pertain to your dog and it does not replace your vet's protocols. I am not a veterinarian, vet tech or canine nutritionist and I am not trained in any medical field.
Notes You made it to the end! Thank you! Very much appreciate that you read the entire post. I already blogged about frozen raw foods and now, other types of raw foods - all of which will be included in Favorite Things soon! In case you are wondering, I do not receive products, product samples or any financial incentives from companies & manufacturers. Free samples were picked up at independent retail stores (get to know your favorite store's owner/manager and they'll be happy to give you samples),
