# Blockchain and Self Sovereign Identity to Support Quality in the Food Supply Chain
## 2 Review
### Certifications in Food Supply Chain
The former is regulated by laws enacted at a national or community level; the latter is freely chosen by the company and, in any case, they refer to quality systems based on rules of a legislative nature, or on rules of a technical nature. The mandatory certifications are certificates that a company is forced to obtain to be able to operate. For example, the certificates that define the use of a valid plan self-control and implementation of the HACCP plan to reduce the risk of food contamination are mandatory certificates. The certifications can then be classified as product or process certifications. Product certification tends to enhance and differentiate certain qualities of a product food. Instead process certifications have as their object the production phases, which carry out the transformations and/or the sale of products or services, and often have the purpose of ascertaining a hygienic-sunitary quality. They attest the ability of an organization to structure and manage its resources and production processes to ensure, for example, the hygienic and sanitary quality through traceability systems and HACCP methodologies. Among the main voluntary certification standards [3; 9] there are:  
* _ISO 9001_ describes the organizational structure, procedures, processes, and resources necessary to implement quality management in a company [10]. * _ISO 22000_ is specific for food safety, and is applicable to all companies involved in the agri-food chain. This standard establishes the Prerequisite Programs (PRP), which integrate with the HACCP principles. These programs are all those prerequisites and activities to be implemented to maintain a hygienic environment throughout the agri-food chain, capable of producing, managing, and supplying products that are safe for consumption. * _ISO 22005_ certifies traceability in the food and feed chain. Organizations wishing to enhance and communicate the origin of the products and raw materials used often resort to this certification. * _IFS FOOD_ (International Food Standard) differently from the aforementioned standards is a product certification, that is, it certifies that agri-food productions are carried out guaranteeing food safety and the healthiness of the products marketed [11]. For a company to be certified IFS it must perform an accurate risk analysis (microbiological, biological, chemical, physical, allergens), know, evaluate, and control all its suppliers, both of raw materials and of primary packaging and material in contact with Foods. * _BRC GLOBAL STANDARD_ offers a set of guidelines for the production of safe food and for the management of product quality, to fully meet customer expectations. The main purpose of this standard is to strengthen and promote food safety throughout the supply chain. The standard applies to food processing and preparation companies and identifies the specific elements of a management system focused on the quality and hygienic-sunitary safety of products, which take as reference the HACCP methodology for the planning and the implementation. IFS and BRC are recognized by the Global Food Safety Initiative (GFSI), which is a nonprofit foundation created under Belgian law in May 2000 to address the issue of differences in standards on a global scale and reduce resultant audit inefficiency. All the voluntary certifications, described above, guarantee an independent and reliable assessment of a company's food safety systems, given that the appropriate checks are performed by certification bodies external and independent of the company.