Additives
What Additives are in Pet Foods?
“What additives are in pet foods?” is a question of interest to pet owners. The purpose of additives (more accurately called “minor ingredients”) are to ensure the stability of nutrients in the diet, food safety such as resistance to spoilage and maintaining the desirable features of pet food such as colour, flavour and texture so the diet remains palatable to the pet. In short, these “additives” are included to enhance the quality of the food and to ensure the food remains in good condition.
The term “additive” can be applied to a range of ingredients and may include essential nutrients such as vitamins and minerals that are important for the health and wellbeing of the pet, as well as flavours, colours and preservatives that are included to enhance the quality of the food and prevent harmful spoilage e.g. for example, preventing the fats and oils in the food from going rancid. These minor ingredients are like those used in human food. Let’s look at some of the important “minor ingredients” that are included and why they are there.
Vitamins and minerals
Many prepared pet foods are carefully formulated to provide all the nutrients needed by the dog or cat in the amounts required. During recipe formulation and cooking, for nutritional completeness, vitamins and minerals are often supplemented as required into the recipe to make sure they are present in the correct amount in the finished pet food. Foods that meet the correct amounts of key essential nutrients may have a statement on the label to say they are “complete and balanced” or something similar advising the food is “nutritionally complete”. This statement essentially means that the pet food is appropriate to feed daily to your pet and no additional supplemental feeding is required.
Vitamins are micronutrients; that is, they are needed by the body in very small amounts. Vitamins enable many important functions in the body and are vital to the health of all animals.
There are two broad vitamin groups- the fat-soluble vitamins A, D, E and K and the water-soluble vitamins, Vitamin C and the B-complex vitamins.
Dogs and cats cannot make all the vitamins they need so these must be supplied in the diet.
Minerals are essential for many of the body’s metabolic processes. They are broadly categorised into two categories: macro-minerals, needed in relatively higher amounts (e.g. calcium, phosphorus, iron) and micro-minerals, which are needed in very small amounts (e.g. cobalt, copper). Where minerals are deficient in a diet or present in excess, the pet may experience issues with their health. An example would be if we feed a diet deficient in calcium to a young growing animal, they will experience serious issues with skeletal development.
Although ingredients used in pet food are selected to be rich sources of these essential vitamins and minerals (e.g. meat is a rich source of the mineral phosphorus), many prepared pet foods will supplement where necessary, to ensure the correct amounts are present for the pet’s health and wellbeing.
Preservatives & Food Processing
Pet food safety is of critical importance. Preservatives (including antioxidants) may be added, largely dependent upon the type of pet food product and processing. Preservatives are used to ensure that food products remain nutritious and safe for consumption throughout their shelf life. The food must be protected from bacterial or mould contamination and spoilage and be protected from the degradation and loss of nutrients over time.
The method of preservation and types of preservatives added depends on the type of food as the type of processing also contributes to the food integrity and shelf life.
Dry foods: the low moisture content helps to inhibit the growth of most organisms.
Moist foods: the heat applied in cooking of canned or foil sachet foods kills microbes and the packaging excludes air, protecting the food.
Chilled foods: processed chilled foods have undergone a controlled thermal process and this, together with refrigeration during storage helps suppress spoilage.
Semi-moist foods: these generally have a low pH and contain humectants that bind water to the product, making it less available for use by invading organisms.
Antioxidant preservatives
Antioxidants are preservatives used to protect foods from deterioration due to oxidation. Most pet foods contain fats and oils essential for the pet’s health, which need to be stabilised. Antioxidants prevent fats from reacting with oxygen in the air (oxidising) and becoming rancid, which leads to losses in nutritional quality, the accumulation of possibly harmful degradation substances and unpleasant odours.
Antioxidants are incorporated into dry foods to protect them from exposure to oxygen after processing. These are not generally added to canned foods because these are cooked at high temperatures, thereby “sterilising” the contents in the sealed, airtight containers. Spoilage can occur if the can is damaged or if left too long after it is opened.
Antioxidant preservatives that might be included in dry pet foods include a variety of herbal or plant extracts such as rosemary extract, citric acid, vitamin E (tocopherols), vitamin C (ascorbates) or synthetic anti-oxidants, which have been used safely in various human foods for many years 1.
Antimicrobials
Antimicrobial agents help protect food from potentially harmful spoilage organisms including mould formation or bacterial putrefaction. Some fresh meat products sold for pet consumption include added sulphite preservatives that release Sulphur Dioxide to suppress microbial growth and spoilage. Sulphites have been included in a range of food and beverage products for humans over many years for a similar purpose. It is known that sulphites degrade thiamine (vitamin B1) and for this reason, the Australian Standard (AS 5812 – Manufacturing and marketing of pet food) includes the following requirement: “Where Sulphur Dioxide or potassium sulphites are used, the common, prescribed, proprietary name or the FSANZ Food Standards Code number shall be included on the label. In this instance, to avoid acute thiamine deficiency in pets, sufficient thiamine shall be present throughout the shelf life of a pet food product. If necessary, this may be achieved by thiamine supplementation”. The Australian Standard (AS5812) requires antioxidants and preservatives to be listed on the statement of ingredients on pet food labels.
Colouring Agents
Colouring agents may be added to pet foods to enhance the appearance of the food. These include a range of naturally occurring food colours, food dyes or mineral based colours. The Australian Standard (AS5812) requires food colours to be listed on the statement of ingredients on pet food labels.
Emulsifiers and stabilisers
Emulsifiers help keep the fat in the food and the water from separating. Gums, lecithin, glycerine and modified starch are used to prevent separation of ingredients and to create the gravy or gel in canned, sachet and other moist pet foods. Food gums include seaweed extracts such as alginate and carrageenan. and seed gums such as guar gum (from the guar plant).
Flavours
Flavours are used to enhance the palatability in some foods and to provide product variation. Much of the appeal of prepared pet foods to the dog or cat stems from the choice of raw materials, such as fish, meat, vegetables or cereals. As with many foods for humans, the cooking process often increases the palatability of many foods. Flavours may be added to some pet foods and these can be natural flavours such as extracts from fish or poultry, or agents designed to emulate natural flavours. The Australian Standard (AS5812) requires flavouring agents to be listed on the statement of ingredients on pet food labels.
Additives: a summary
- “Additives” or “minor ingredients” covers a wide range of recipe ingredients that are included in pet foods.
- They are important ingredients that are included for very specific and varied purposes.
- These “additives” include essential food ingredients such as vitamins and are therefore incorporated into pet foods when considered necessary, at the appropriate level to enhance the quality, appeal and safety of prepared pet foods.
This article is for general information only:
This information is provided by the PFIAA as general information only. For advice and information concerning feeding your individual pet, we recommend that you seek the advice of your veterinarian.