With the development of biotechnology in recent years, its application areas have expanded beyond the traditional fields of fermentation and brewing to a variety of areas in the bio-industry. An indispensable technological field in biotechnological manufacturing is "baiyo". The Japanese word "baiyo" is translated as "culture" or "cultivation" in English. The English word culture includes way of life, art, and customs, the attitudes and beliefs and the practice of growing crops or fish, and other concepts not found in the Japanese word "baiyo". The Japanese word "baiyo" is an expression unique to the Japanese language that mainly refers to the propagation of "cells" as the basic unit in an artificial environment, and clearly refers to the cultivation (increase) of organisms (cells) for some purpose by humans. This special issue focuses on the cultivation of cells, from case studies to human resource development. I hope that readers will understand the fun, difficulty, and pleasure of manufacturing through "baiyo" as well as the importance of human resource development.

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Yeast and lactic acid bacteria are used industrially in a variety of applications, including food products. Baker's yeast is produced at an annual rate of 3.5 million tons worldwide, mostly by aerobic-fed batch culture using waste molasses as a sugar source. Yeast can regenerate NAD⁺, which is consumed in the glycolytic system, using oxygen as an electron acceptor and simultaneously obtaining energy by respiration. However, when the supply of sugar exceeds its respiratory capacity, ethanol is produced as a byproduct to compensate for the deficient NAD⁺ by the reaction of alcohol dehydrogenase, resulting in a decrease in cellyield. Therefore, in industrial cultivation of yeast, the feed rate of sugar is controlled to prevent aerobic fermentation using the respiration quotient or ethanol concentration as an indicator. Lactic acid bacteria are facultative anaerobes and are often produced in a non-aerated batch culture using skimmed milk powder or cheese whey as a main nutrient. Most lactic acid bacteria can regenerate NAD⁺ by membrane-bound NADH oxidase (NOX) using oxygen as an electron acceptor. However, NOX undergoes glucose repression and may produce hydrogen peroxide that causes oxidative stress. Therefore, an aerobic-fed batch culture with the addition of catalase can suppress the production of lactic acid and, as with yeast, can be cultured to high concentrations with high yields, which reduces production cost of lactic acid bacteria.

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Microbial media are composed of various nutrients including specific chemicals and natural raw materials and their extracts. Since there are many different types of microbial culture media, optimization is difficult with only experimental testing. Here, two different approaches will be introduced: metabolomics profiling, and optimization assisted with machine learning. In metabolomics profiling, data from non-targeted comprehensive analyses can be used to find significant components in raw materials and their extracts with statistical calculat ion and machine learning. Optimization with assisted machine learning consists of data sampling, validating machine learning, and maximum value search by optimization algorithms. This optimization method optimized a medium with 31 components for protein expression by Escherichia coli.

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Toward the realization of a bioeconomy and a sustainable society, a bio-manufacturing system using bioreactors cultivating microorganisms has attracted much attention. In the future, it is expected that many new bioproduction systems will be developed not only by existing biotechnology companies, but also by emerging bio-ventures. On the other hand, the development of bioproduction technology has many difficulties because it deals with extremely complex phenomena, and the barriers to entry for newcomers are historically well known. In this paper, we discuss what is considered essential to eliminate barriers to new entrants (shortening of optimization period, support for prototyping, human resource development, automation, and labor saving) in order to accelerate the industrial bio-production field.

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Protein is one of the three major nutrients contained in food. The type of food from which protein is obtained is an important issue for mankind in terms of population growth and global environmental protection. Recently, the production of alternative proteins, such as cultured meat, is being considered as a substitute to meet the rapidly increasing demand for meat (protein) due to rapid population growth, and foods made using biotechnology are attracting more attention. Proteins are also used as functional food materials because of their excellent emulsifying and foaming properties. The relationship between the physical properties and functionality of proteins has been studied using various analytical technologies.
Regarding quality of cultured meats, we show the difference between cultured and conventional meats and recent evaluation of quality related to secondary functions in foods. Also, the latest findings on foaming properties and physicochemical properties of food proteins are also presented.
Technological advances in recent years have made it possible to produce cultured meat at a lower cost. In addition, it has become possible to produce meat that is equivalent to conventional meat products in terms of firmness and chewiness. In order to develop cultured meat that is more similar to conventional meat, it is necessary to understand the reactions that occur in cultured meat that are equivalent to rigor mortis and ripening in meat.
Protein structure and physical properties at the interface are essential for understanding foaming properties of food proteins. Many studies have been conducted, and the relationship between physical and foaming properties was clarified. However, the understanding of foaming properties from the protein structure aspect has not been studied in detail.
Accurate and more detailed analysis of food proteins and the linking of analytical results with production research are needed to develop cultured meat that is more acceptable to consumers and to develop higher value-added foods.

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Panax ginseng, P. quinquefolius and P. notoginseng, including white ginseng and red ginseng prepared by air-drying and steaming or heating processes, respectively, are widely used herbal medicines which require rigorous quality control to assure their consistent bioactivities. Therefore, many analytical methodologies have been developed, primarily with a focus on high performance liquid chromatography (HPLC). On the contrary, monoclonal antibodies (MAbs) against ginsenosides such as ginsenosides- Rb1, -Rg1, -Re, and notoginsenoside R1 were applied to newly developed techniques like the eastern blotting system, one-step separation method, and preparation of knockout extract from ginseng. The anticancer activities of red ginseng are significantly increased due to the production of active anticancer ginsenosides during steam processing compared to white ginseng, resulting in the induction of apoptosis/paraptosis and inhibition of angiogenesis. Future studies should focus on characterizing active red ginseng derivatives as potential anticancer drugs. Cognitive activities of major ginsenosides and their mechanisms were also widely confirmed. Clinical trials of ginseng administered to Alzheimer's patients confirmed its activity without side effects, with the result that ginseng may be a potential new medicine to treat Alzheimer's disease.

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The Maillard reaction (aminocarbonyl reaction) is a reaction that produces a pleasant aroma when baking bread or cookies and contributes to the formation of a visually appetizing baked color. This reaction can be beneficial or harmful depending on where it occurs. We investigated ways to utilize it in order to expand the positive aspects of these reactions that is familiar to us in food. In order to use the aroma generation by the Maillard reaction as a new food processing technology, we investigated a method for designing various aromas, and created Maillard reaction-type aroma addition technology. Based on the aroma generated when lactose, which is a reducing sugar, and various amino acids were mixed and heated, we found the key points for designing the desired aroma by allowing multiple amino acids to coexist. In a detailed design of the aroma, the most important points were the three elements of amino acid type, number, and ratio. We propose a new method for producing flavored kamaboko, using the example of adding aroma to kamaboko using Maillard reaction-type aroma addition technology.

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Algal biomass, called blue carbon, is attracting attention as biomass that is capable of fixing CO₂ rapidly. Fast-growing green algae such as Ulva meridionalis are expected to be used for CO₂ fixation and for bioremediation of eutrophic sea areas. U. meridionalis rapidly assimilates CO₂ as a sulfated polysaccharide called "ulvan". Microwave-assisted extraction processes can achieve efficient extraction of ulvan. Furthermore, ulvan can be efficiently converted to monosaccharides by using microwave heating and polyoxometalates as an environmentally benign superacid catalyst. The sulfated structure of ulvan was effective both for collection of microwave energy and for efficient extraction and conversion of ulvan by microwaves. Rapid CO₂ fixation by U. meridionalis and effective utilization of ulvan by microwaves represents a new carbon-neutral chemical process based on algal biomass.

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Tarashiyaki is one of the traditional home-cooked dishes found in rural Japan. It is made by baking wheat flour dissolved in water in a frying pan. This paper reports on the usage of tarashiyaki before the period of high economic growth based on interviews conducted in Gunma Prefecture. In this prefecture, where wheat cultivation has thrived, various powdered foods such as udon, suiton, steamed buns, and yakimochi have been made since ancient times. Among them, tarashiyaki was mainly used as a snack because it was easy to make. Miso was often used as a seasoning because home-brewed miso was common in rural households in Gunma Prefecture at the time. Tarashiyaki is not only made from wheat flour. In mountainous areas, it was sometimes made from buckwheat flour or corn flour, so it varied from region to region. In addition, there are various names for tarashiyaki, such as jiriyaki, mizuyaki, and senbeiyaki. Even within the same prefecture, there are various names depending on the region. The reason for differing names is related to tarashiyaki's role in the local diet. It is thought that local names for the dish did not circulate freely between regions because it was a food that was only eaten occasionally among families.

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