## 3 In Silico Studies on the Biological Activities of Meat Peptides--Theoretical Approach  
Increasing the knowledge on the impact of food on human health is currently one of the most important research areas for scientists worldwide, and it is also of interest to consumers who want to consciously compose their daily diets. This interest is based on the fact that, during metabolism, food is broken down into components that, in addition to providing nutritional value, may have biological activity. Protein is one of the most important compounds supplied to the body through the consumption of food. In addition to having structural, transport, regulatory, immune, and other functions, proteins are also a potential source of peptides with biological properties. A crucial aspect in assessing the bioactivity and bioavailability of peptides is to understand the mechanisms by which gastrointestinal enzymes catalyze the hydrolytic degradation of the proteins supplied with food. These mechanisms have been investigated by studies conducted by the European Cooperation in the Field of Scientific and Technical Research (COST), under the project name, COST INFOGEST [37]. As part of this project, research was conducted, in 34 countries globally, on the mechanisms of the digestion of food products, with a focus on the compounds released from proteins and known to have a potential effect on human health. One of the other goals of the project was to standardize the digestion models used in the research. According to the assumptions of INFOGEST, activities in this area should cover the research areas presented in Figure 2.  
Importantly, in line with the COST INFOGEST policy of standardizing research practices, in silico digestion models were developed as Gut Map--a common reference library for in silico models related to food digestion. It is open to anyone via the Internet in order to share this work with the widest community. The evaluation of the potential of food proteins to generate peptides is essentially based on the following steps: (I) Selecting the protein source with the highest potential for releasing an active sequence; (II) Hydrolytic peptide release (proteases/fermentation/ gastrointestinal digestion); (III) Evaluation of biological activity; and (IV) Fractionation/isolation and characterization of peptides. To understand the unique properties of peptides released from food proteins, these steps can be accomplished by two approaches: conventional in vitro/in vivo testing, and computer-assisted techniques (in silico approach) (Figure 3). Figure 2: The main directions of research on the mechanisms of food digestion in order to release bioactive substances. A bioinformatics approach to identifying and analyzing bioactive food-derived peptides has been presented by [PERSON] et al. [39], [PERSON] et al. [40], [PERSON] et al. [33], [PERSON] et al. [41], and [PERSON] et al. [42]. Research on the activity of biopeptides in food is carried out in three main directions, with the aim of developing and validating methods for obtaining and assessing their biological value: (I) Obtaining detailed knowledge on the mechanisms of generating bioactive peptides from precursor proteins; (II) Determining the biological properties of the peptides; and (III) Learning about the structures and properties of biologically active peptides that can serve as standards for designing synthetic peptide analogs or mimetics. The computational methods used in in silico research may be helpful in developing the abovementioned stages. This approach is becoming more common and has been recognized by scientists to be as important as in vitro experimental research, especially when used as part of an integrated approach.