Shelf life of a product

It is normal to employ beverage-processing steps that lead to a reduction in the likelihood of haze formation, or at least a delay the onset of haze development beyond the intended shelf life of a product. 

Heat is a form of energy that affects the rate at which chemical reactions take place. The shelf life of a product can therefore be considerably reduced by exposure to elevated temperatures. Odor deterioration and discoloration will develop much faster under these conditions, and this is exploited in the accelerated testing of perfumes for stability in final products. Some products are manufactured at quite high temperatures, and perfumers have to keep this in mind in the formulation of their fragrances. 

While appearance, texture, and flavor are each important for most products, their relative importance will vary between products. For leafy salads, for example, texture and appearance may be more important determinants of quality than flavor. For pre-sliced fresh fruit, which is to be used in remanufactured foods, flavor and texture may be more important than appearance. The shelf-life of a product is measured as the time from preparation until one quality factor degrades to a level where it is unacceptable. Therefore it is necessary to treat or process the product so that all quality factors have about the same stability even though one factor is considered... 

The above more conventional procedures (newer procedures will be considered later) might be used to test product-pack efficiency in terms of its protective role against egress during the shelf life of a product. A similar series of tests can be considered where ingress may be the evaluation factor. 

The Woolfe equation has been used to estimate the shelf life of a product from data obtained at the same temperature/conditions as those expected for the final product.764 The time at which drug content diverges from its specifications is estimated by extrapolating the time course of degradation at a specific temperature/condition. When the time course of drug content (C) is represented by... 

The storage conditions recommended by manufacturers on the basis of stability studies should guarantee the maintenance of quality, safety, and efficacy throughout the shelf-life of a product The effect on products of the extremely adverse climatic conditions existing in certain countries to which they may be exported calls for special consideration (see section 6). 

The shelf life of a product should be included in the Finished Product Specification and the Master Production Document respectively. 

Based on the experiences of the author in ref. 8, here are some guidelines to approximate the shelf life of a product at a desired temperature. 

The concepts discussed in Section 14.4 describe the situation that will eventuate when a multiphase packaging system reaches thermodynamic equilibrium. However, the rate of mass transfer of permeant, sorbate, and migrant molecules in the polymer is not addressed by these equilibrium considerations. For example, if we consider a potential migration process, we know that eventually the migrant will be transferred to the food and it will finally reach equilibrium, but based on the equations presented in Section 14.4 we cannot predict how long the process will take. Similarly, these relationships will not allow us to estimate the shelf life of a product in a particular package system. For this, we need to look at diffusion. 

Microencapsulation is an effective and longlasting method of protecting unstable or reactive products against external influences such as oxidation, alkalinity, acidity, heat, polluting gases, moisture and evaporation, and in this way it can be used to increase the shelf life of a product. Microencapsulation prevents unwanted... 

Solubility coefficient values are of great use in predicting permeant-polymer compatibility however, for packaging applications permeability coefficient values better describe the quality of the barrier of a material, and are more useful in calculating the shelf life of a product. Fig. 6b compares the ethyl acetate permeabihty coefficient values of PLA, LDPE [49], PP [50], and PET [51]. Ethyl acetate permeability coefficients in PLA are lower than those for PP and LDPE and slightly higher than those for PET. RST cannot be used to predict permeability coefficients since it helps only to obtain the relation between solubility and AS, which is not enough to predict permeability and also depends on the diffusion coefficient. 

VOCs also have an influential role in food science and technology. They are present in foods and drinks and their presence is intimately involved in aroma and flavor. Both of these factors influence the choiee and preference of consumers. Further, VOCs emitted by foods can provide evidence of the shelf life of a product, of the ripening stage, and whether product adulteration has occurred. The human olfactory threshold can be as low as the pptv range for key aroma compounds, so sensitive analytical techniques are required for interrogatioa... 

The preservation of packaged food is the main concern to the food industry. Shelf life of a product in a package is defined as the time during which it is... 

---