The starting point for the study of food science lies in the knowledge of both the chemical components of food and the reactions that lead to changes in the constitution and characteristics of these substances.
These compounds contain radicals or chemically active parts that can participate in complicated reactions with each other and the media surrounding the food, such as air, water, packaging, processing equipment, etc.
During preparation, foods are exposed to moisture, heat, cold, interaction with other materials and substances, which can induce different reactions; this reactivity means that foods must be considered chemical systems that are changing rapidly and permanently.
For example, the study of water and the analysis of the elemental and mineral composition of food implies that food safety net services destroy the molecular structures of which these elements are part; whereas, in the study of the molecular design of food, the integrity of the various molecular entities must be preserved to characterize them and discern their behavior and their contribution to the properties and quality of the food. This identification and discernment must then refer not only to the compounds that constitute the nutrients but also to other compounds in the food that contribute to defining the properties, behavior, and quality of food products or that are simply fillers, food waste, or moreover, actually or potentially represent substances that are undesirable for the consumer or toxic and harmful to his organism.
The characterization of food comes from the results of the different tests to which they can be subjected using other evaluation methods, which can be grouped according to the objectives they pursue and the principles on which they are based. Thus, food safety net services usually involve three types of analysis: physicochemical analysis, microbiological analysis, and sensory analysis.
Physicochemical analysis: This involves the characterization of food from the physicochemical point of view, with emphasis on the determination of its chemical composition, i.e., which substances are present in a food (proteins, fats, vitamins, minerals, carbohydrates, metal contaminants, pesticide residues, toxins, antioxidants, etc.) and in what quantities these compounds are found. The physicochemical analysis provides powerful tools to characterize a food from a nutritional and toxicological point of view and constitutes a scientific discipline of enormous impact on the development of other sciences such as biochemistry, medicine, and pharmaceutical sciences, to mention a few.
Microbiological analysis: Foods are complex systems of great nutritional richness and therefore sensitive to attack and subsequent development of microorganisms (bacteria, fungi, and yeasts). There is always a specific microbial load in all foods, but this must be controlled and must not exceed certain limits, beyond which the deterioration of the product begins to occur with the consequent loss of its quality and suitability for consumption. On the other hand, there are pathogenic microorganisms that produce diseases and whose presence is, therefore, undesirable and makes their consumption extremely dangerous.
Microbiological analysis is therefore carried out to identify and quantify the microorganisms present in a product and constitute a powerful tool in determining the hygienic-sanitary quality of a food manufacturing process, which makes it possible to identify those stages of the process that may favor product contamination.
Sensory analysis: This is a scientific discipline that evaluates, measures, analyzes, and interprets the sensory characteristics of food (color, odor, flavor, and texture) using one or more human sense organs. Although sensory evaluation is the most subjective analysis, since the measurement instrument is the human being, it often defines the degree of acceptance or rejection of a product. For example, a food that is not pleasing to the palate, sight, or smell will not be accepted, even if it contains all the necessary nutritional constituents and is microbiologically suitable.
