These are real-time studies that consist of storing the product under conditions similar to those that it will actually face, to monitor its evolution in regular intervals of time. The main advantage of this method is that it creates a very accurate estimation of the time it takes for a product to deteriorate; however, they are studies that usually take a long time and do not consider the fact that storage conditions of a product are not always stable over time.
This method consists of experimentally introducing pathogens or microorganisms into the food during the production process, so that the product is exposed to the real conditions it will suffer in real life. The main disadvantage of this type of test is that the effects caused by the studied parameters are the only things analysed, and the fact that the product can be faced with multiple factors at the same time is not addressed. In addition, they are studies that are quite complex and difficult to implement.
This methodology studies the different microbial responses of foods to varying environmental conditions, based on mathematical and statistical models, in order to predict the behaviour of the microorganisms in the product. This type of study, widely used when developing a new product, does consider the possible changing conditions of a product, however, its major limitation is that it implies greater complexity for the manufacturer and that the results correspond to a simulation, which may not be accurate
Accelerate shelf life tests
In these tests, conditions such as temperature, oxygen pressure or moisture content are modified to accelerate spoilage reactions of a food. These predictions allow one to predict the behaviour of foods in certain conditions and to estimate how they will evolve under certain storage conditions. Accelerated tests allow the inclusion of changing environmental conditions and concentration variations of the ingredients that they are composed of. These studies are very versatile, low cost for the manufacturer and allow for the comparison of different scenarios. Obviously, since it is not an exact representation of reality, there is some margin of error in the obtained results.
It is a type of study that is based on the opinion of the consumer about the physical characteristics of the product. It consists in knowing the attitude of people towards the same product with different dates of manufacture, to determine if they would consume it or not. This method seeks to establish a relationship between the shelf life and the perceived quality of the product. Although it is not a method to accurately estimate the shelf life, it is important to do it in a complementary way to establish the best by date of a product.
The interest in preserving food goes very far back in time. Salting, pickling or drying in the sun and air were the first attempts to extend the shelf life of food. Today, thanks to food industrialisation, companies have the responsibility to determine the shelf life of their products and to provide good quality food.