Comparing Premixes, Base Mixes and Blends
16 September 2020
By Mike Trapp
Territory Sales Manager
The Association of American Feed Control Officials (AAFCO) sets specific nutrient minimums and maximums for both cats and dogs, which vary by life stage. Delivered at such precise and small quantities, vitamins and trace minerals can be cumbersome to weigh and measure and challenging to disperse equally throughout the pet food. Thankfully, premixes, base mixes and blends provide effective methods for delivering these nutrients efficiently and safely.
Premixes Provide Convenience
A premix is a fairly potent mixture of vitamins, trace minerals or a combination of both, designed to provide those micronutrients to the pet food. The addition rate is typically 1-10 lbs/ton. The components in a premix include:
- Actives: Required vitamins and/or trace minerals
- Carriers: Used to properly disperse actives and limit ingredient segregation. Rice hulls or pea fiber, for grain-free foods, are the most common carriers.
- Densifier: Used to achieve a target bulk density. Most commonly this is calcium carbonate.
- Dust suppressant: Used to limit dust associated with the active ingredients and hold the carrier and actives together, while also serving as a dust suppressant to improve work safety. Most commonly this is a small amount of vegetable oil.
Premixes are more convenient for pet food manufacturers and provide several benefits versus adding the individual ingredients. First, adding a premix improves blending and dosing accuracy, which improves the nutritional adequacy and consistency of the final food. Second, premixes reduce the number of ingredients pet food manufacturers need to inventory.
For maximum premix shelf-life, vitamins and trace minerals should be separate, since trace minerals can degrade vitamin potency over time. A vitamin premix’s shelf life typically ranges 6-12 months and a mineral premix’s shelf life is typically 12-24 months, but combining the two into a vitamin-trace mineral premix tends to reduce shelf-life to about three months.
Reduce Inventory Needs with Base Mixes
A base mix can be a combination of many ingredients and is added at a higher rate in pet foods than a premix, typically at 50-200 lbs/ton of pet food. A base mix usually contains:
- Required vitamins
- Trace minerals
- Amino acids
The other contents of a base mix may vary but could include:
- Major minerals
- Spray-dried egg
- Beet pulp
- Fruit and/or vegetable powders
- Prebiotics, such as BENEO’s Orafti® Inulin
- Kelp, such as Tasco®
- Sources of grains or lentils, such as rice flour, corn grits, ground peas, potato or tapioca starch
- Animal or vegetable proteins, such as meat meals
- Spray-dried, novel proteins, such as duck or bison
A base mix provides similar benefits as a premix, including convenience, greater batching efficiency and accuracy, decreased raw material purchasing and inventory. However, depending on the ingredients, a base mix has a shorter shelf-life (typically around three months) than a premix and may clump or harden if hygroscopic ingredients, such as salt or choline chloride, are included.
Microbial Sensitive Blends
Typically, most premixes and base blends are added during batching and are extruded, thus going through a microbial kill-step. However, there are situations in which a pet food manufacturer requires a blend of ingredients that will not go through a kill-step and are sensitive to microbial contamination. These blends include fruits, vegetables, palatants, probiotics or a combination of all these. Raw or minimally processed diets and supplements also require the blends to be pathogenic bacteria-free. In both situations, the blends need to be tested for microbial contamination after blending.
A post-kill step fruit-vegetable blend could include pieces, such as diced apples, crosscut or flaked carrots and whole peas. Post-kill step palatants and/or probiotic blends are dusted on the kibble after fat is applied. Applying a probiotic blend at this time helps maintain viable bacteria. A probiotic blend might contain several strains of bacteria, enzymes and moisture scavengers to keep the formula dry and improve shelf life. Palatant blends applied to the kibble post-extrusion could contain ingredients, such as probiotics, enzymes and ImmuFlexTM, spray-dried egg powder with ready-to-feed antibodies, to support pets’ immune systems.
Adding a base mix or blend to your pet food operation becomes even easier with custom-sized bags. For example, Trouw Nutrition can bag base mixes and blends in precisely the amount required per batch, alleviating pet food manufacturers of the hassle of weighing and measuring each bag and problematic partial bags.
Customers’ specific needs and challenges help determine which route will best accomplish their goals. Premixes, base mixes and blends each come with their advantages and disadvantages, but ultimately they all provide added convenience, safety and nutritional accuracy.