# Bioreactors: Applications and Innovations for a Sustainable and Healthy Future--A Critical Review
## 6 Recent Advances in Bioreactor Applications
### Food Production  
SSF is widely used in the production of foods fermented by filamentous fungi in oriental cultures. In Japan, Koji, a specific fungal culture produced from steamed cereals, is used to obtain miso, shoyu, sake, and other products. After World War II, with the modernization and industrialization of Japan, the processes for obtaining Koji began to be developed in bioreactors on a larger scale, made of stainless steel or plastic and with aeration of the types (I) internal ventilation, (II) surface ventilation, and (III) non-ventilated (Table 5). The market for _Koji_ fermentation equipment is dominated by internal ventilation bioreactors with various configurations [22]; [[https://controlledhold.com/industrial-koji-fermentation-equipment/](https://controlledhold.com/industrial-koji-fermentation-equipment/)]([https://controlledhold.com/industrial-koji-fermentation-equipment/](https://controlledhold.com/industrial-koji-fermentation-equipment/)) Accessed on 1 September 2024). In addition to traditional fermentation processes for obtaining food, studies on cultured meat (also known as artificial meat or in vitro meat) are currently being highlighted. Artificial meat is produced through the process of in vitro myogenesis. When compared to the conventional meat that today's society consumes, laboratory-grown meat has some advantages, such as (i) the reduction of greenhouse gas emissions into the atmosphere, as it is not necessary to maintain large herds, and (ii) the reduction of the huge number of animals [130; 131]. Aiming to achieve increasing industrial production rates, studies to obtain cultured meat using bioreactors with different configurations are of fundamental importance. Currently, studies can be found that report the production of meat on a bench and pilot scale using STR reactors in batch, fed-batch, and continuous modes. According to [PERSON] [132], the use of STR bioreactors in continuous mode when compared to batch mode has as its main advantage more optimized cell growth rates, due to the maintenance of nutrient levels. In addition, a subtype of continuous batch reactors, known as perfusion reactors, is based on changing the culture medium without disturbing the cellular content of the reactors, which allows for achieving maximum recycling of the medium and the volume of the container. However, this bioreactor type depends on cell retention devices, ensuring uninterrupted cell proliferation and differentiation during medium change [133]. Culture systems based on recirculation of the cell culture supernatant (Alternating Tangential Flow, ATF; Tangential Flow Filtration, TFF), which differ from normal flow filtration, are also used in the context of perfusion reactors. They are designed to achieve cell retention and increase cell density [131; 134]. In addition to mechanically agitated STR bioreactors, studies have also been carried out with pneumatic bioreactors, such as hollow fiber and airlift. Although pneumatic reactors ensure lower shear stress on cells and allow a relatively easy exchange of nutrients and gases between the culture medium and cells, they have the disadvantages of limited scalability, propensity for clogging, limited oxygenation, and relatively high cost [135]. Finally, when designing a bioreactor for the production of cultured meat, several issues must be considered: (i) the bioreactor may need to have a surface for cells to adhere to or be able to support growing cells attached to scaffolds; (ii) the setup should be simple and make use of safe and inexpensive materials, aiming to reduce manufacturing costs; (iii) the setup should allow for easy scalability, aiming at the development of equipment for larger volumes [131]. Future Perspectives: Trends for the Future of Bioreactor Systems and the Impact of Advances in Bioreactors on Society and Industry  
Looking ahead, the evolution of bioreactor systems holds profound implications for both industry and society.