With few new pet foods entering the market, pet food has always been one of the most competitive industries.
Reliable methods are increasingly needed to ensure and extend the shelf life of pet food.
Like human food, pet food must ensure that it meets the life and health of the pet.
Therefore, pet food should maintain the necessary nutrition and original flavor within the delivery, maintenance and shelf life.
Preservatives have been used for centuries.
They might be.
Microbial preservatives that inhibit the growth of bacteria and fungi, or antioxidants that inhibit the oxidation of food ingredients, such as oxygen absorbers. Common anti-
Microbial preservatives include C- calcium, sodium nitrate, nitrite, and sulfuric acid (
Sulfur dioxide, sodium bisultan, potassium bisultan, etc. )
Antioxidants include BHA and BHT.
Food preservatives are divided into: natural preservatives such as salt, sugar, vinegar, syrup, spices, honey, edible oil, etc;
And chemical preservatives such as sodium or potassium, sulfate, glutamate, gan grease, etc.
However, the side effects of artificial preservatives on pet foods are more serious than natural preservatives.
In terms of the type and quantity added to pet food, there are increasingly strict regulations.
It is increasingly difficult for manufacturers to rely on preservatives to ensure shelf life.
The use of high barrier materials as pet food packaging is also very helpful to ensure and extend the shelf life of pet food.
It is well known that the growth of microorganisms requires a suitable environment.
Temperature, oxygen and water are the three most important factors.
Oxygen is the main cause of food decay.
The less oxygen is in the food package, the less likely the food will rot.
While water provides living environment for microorganisms, it can also speed up the reduction of fat;
Shorten the shelf life of pet food.
During the shelf life of pet food, oxygen and water vapor in the package should be kept pre-filled.
Permeability is the ability to measure the gas allowed by barrier materials (
O2, N2, CO2, water vapor, etc. )
Penetrate into it at a specific time.
It usually depends on the type, pressure, temperature and thickness of the material.
In Labthink lab, we tested, analyzed and OPP/PE/CPP, oxygen transfer rate and water vapor transfer rate for 7 commonly used pet food packaging PET, pet CPP, Bopp/CPP, BOPET/PE/ VMPET/dlp.
High oxygen permeability rate means that material oxygen permeability reduce;
The high water vapor transmission rate means that the water vapor permeability of the material is low.
The oxygen delivery test adopts the Labthink OX2/230 oxygen delivery rate test system, equal pressure method.
Place the sample in a standard environment before testing (23±2℃、50%RH)
For 48 hours, air balance on the surface of the sample.
The water vapor transmission rate test uses the Labthink/030 water vapor transmission rate tester and the traditional Cup method.
The detailed OTR and WVTR test results of these 7 packaging materials are as follows: sample test results OTR (ml/m2/day）WVTR (g/m2/24h)PET/CPP 0. 895 0.
667 BOPP/CPP 601. 725 3. 061 PET 109. 767 25.
BOPET/PE 85 163. 055 4.
632 OPP/PE/CPP 716. 226 2.
214 BOPET/VMPET/hdpe 0. 149 0. 474 Aluminum-plastic 0. 282 0.
187 Table 1 from the analysis of the test results of these 7 packaging materials, the test data of the permeability of Pet food packaging can be found, and we can find that different laminated materials will have significant differences in oxygen permeability.
From Table 1, aluminum-
Oxygen transfer rates for plastic materials, BOPET/VMPET/dlp, PET/CPP are relatively low.
According to our research, pet food in this package usually also has a longer shelf life.
Laminated film has good performance in preventing water vapor.
Refer to the picture below, PET has a high water vapor transmission rate, which means that its water vapor barrier has poor performance and is not suitable for PET food packaging because it will shorten the shelf life of PET food.
Pet food manufacturers can use high barrier materials instead of more preservatives to extend the shelf life of pet food.
We recommend laminated plastic, aluminum-
Plastic and metal materials are packaged as pet food because all of them have a good barrier to oxygen and water vapor.
In addition to considering the oxygen and water vapor permeability properties of the material, we should also know that the environment has some influence on these properties of the material.
Like EVOH and PA, they are very sensitive to humidity.
At room temperature and relatively low humidity, both have a good blocking effect on water vapor, while their water vapor permeability decreases in high humidity environments.
Therefore, EVOH and PA are not suitable for packaging if there is a high humidity environment during pet food transportation and maintenance.