Cultured beef: medical technology to produce food

Development of a novel Japanese eel myoblast cell line for application in cultured meat production

The present study investigates the isolation, analysis, and characterization of primary cultured cells derived from the muscle tissue of Japanese eel (Anguilla japonica), culminating in establishing a spontaneously immortalized myoblast cell line, JEM1129. We isolated satellite cells from eel muscle tissue to establish a foundation for cultured eel meat production. While initial cell cultures contained myoblasts, continued passaging led to a decline in myoblast characteristics and an increase in fibroblast-like cells. RNA-Seq and RT-qPCR analyses showed significant downregulation of well-established markers for satellite cells and myoblasts, such as pax7a and myoD, over successive passages, highlighting a loss of myoblastic traits. Single-cell cloning was employed to overcome this challenge and maintain myoblast purity, leading to the successful creation of the JEM1129 cell line. These JEM1129 cells demonstrated enhanced expression of myoblast marker genes, exceeding the initial primary culture cell population. The cells showed strong myotube formation, particularly when cultured in a differentiation medium, indicating their robust potential for muscle development. The JEM1129 cell line represents a significant advancement in the cultivation of eel muscle cells, offering a promising avenue for cultured meat production. The findings contribute to a deeper understanding of muscle cell biology and provide valuable insights into using fish-derived myoblasts for cultured meat production.

Stable cytoactivity of piscine satellite cells in rice bran-gelatin hydrogel scaffold of cultured meat

In order to achieve high cell adhesion and growth efficiency on scaffolds for cultured meat, animal materials, especially gelatin, are necessary though the disadvantages of weak mechanical properties and poor stability of their hydrogel scaffolds are present during cell cultivation. Here, we use rice bran as a kind of filling and supporting materials to develop a composite scaffold with gelatin for fish cell cultivation, where rice bran is also inexpensive from high yield fibrous agricultural by-product. The rice bran (with a proportion of 1, 3, 5, 7, 10 to 3 of gelatin) could evenly distributed in the three-dimensional network composed of gelatin hydrogel. It contributed to delaying swelling and degradation rates, fixing water and improving elastic modulus. It is important that rice bran-gelatin hydrogel scaffolds (especially the hydrogel with 70 % rice bran, db) promoted piscine satellite cells (PSCs) proliferation effectively compared to the pure gelatin hydrogel, and the former could also support the differentiation of PSCs. Overall, this work showed a positive promotion to explore new source of scaffold materials like agricultural by-product for reducing the cost of cell cultured meat production.

Effect of Chicken Age on Proliferation and Differentiation Abilities of Muscle Stem Cells and Nutritional Characteristics of Cultured Meat Tissue

This study aimed to investigate effects of chicken age on proliferation and differentiation capacity of muscle satellite cells (MSCs) and to determine total amino acid contents of cultured meat (CM) produced. Chicken MSCs (cMSCs) were isolated from hindlimb muscles of broiler chickens at 5-week-old (5W) and 19-embryonic-day (19ED), respectively. Proliferation abilities (population doubling time and cell counting kit 8) of cMSCs from 19ED were significantly higher than those from 5W (p<0.05). Likewise, both myotube formation area and expression of myosin heavy chain heavy of cMSCs from 19ED were significantly higher than those from 5W (p<0.05). After cMSCs were serially subcultured for long-term cultivation in 2D flasks to produce cultured meat tissue (CMT), total amino acid contents of CMT showed no significant difference between 5W and 19ED chickens (p>0.05). This finding suggests that cMSCs from chicken embryos are more suitable for improving the production efficiency of CM than those derived from young chickens.

Scaffolding fundamentals and recent advances in sustainable scaffolding techniques for cultured meat development

In cultured meat (CM) production, Scaffolding plays an important role by aiding cell adhesion, growth, differentiation, and alignment. The existence of fibrous microstructure in connective and muscle tissues has attracted considerable interest in the realm of tissue engineering and triggered the interest of researchers to implement scaffolding techniques. A wide array of research efforts is ongoing in scaffolding technologies for achieving the real meat structure on the principality of biomedical research and to replace serum free CM production. Scaffolds made of animal-derived biomaterials are found efficient in replicating the extracellular matrix (ECM), thus focus should be paid to utilize animal byproducts for this purpose. Proper identification and utilization of plant-derived scaffolding biomaterial could be helpful to add diversified options in addition to animal derived sources and reduce in cost of CM production through scaffolds. Furthermore, techniques like electrospinning, modified electrospinning and 3D bioprinting should be focused on to create 3D porous scaffolds to mimic the ECM of the muscle tissue and form real meat-like structures. This review discusses recent advances in cutting edge scaffolding techniques and edible biomaterials related to structured CM production.

Cultivated meat: research opportunities to advance cell line development

Cultivated meat offers an avenue to feed a growing population and reduce environmental burdens associated with conventional meat production. In this Science & Society paper, we outline challenges the industry is facing in obtaining robust cell lines for the development of cultivated meat products. Through an industry survey, several knowledge gaps in cell biology were identified and are presented as research opportunities here. Continued fundamental research is essential to enhance the availability of suitable cell lines and enable cost-effective and large-scale manufacture of cultivated meat.

Biofabrication's Contribution to the Evolution of Cultured Meat

Cultured Meat (CM) is a growing field in cellular agriculture, driven by the environmental impact of conventional meat production, which contributes to climate change and occupies ≈70% of arable land. As demand for meat alternatives rises, research in this area expands. CM production relies on tissue engineering techniques, where a limited number of animal cells are cultured in vitro and processed to create meat-like tissue comprising muscle and adipose components. Currently, CM is primarily produced on a small scale in pilot facilities. Producing a large cell mass based on suitable cell sources and bioreactors remains challenging. Advanced manufacturing methods and innovative materials are required to subsequently process this cell mass into CM products on a large scale. Consequently, CM is closely linked with biofabrication, a suite of technologies for precisely arranging cellular aggregates and cell-material composites to construct specific structures, often using robotics. This review provides insights into contemporary biomedical biofabrication technologies, focusing on significant advancements in muscle and adipose tissue biofabrication for CM production. Novel materials for biofabricating CM are also discussed, emphasizing their edibility and incorporation of healthful components. Finally, initial studies on biofabricated CM are examined, addressing current limitations and future challenges for large-scale production.

Dairy, Plant, and Novel Proteins: Scientific and Technological Aspects

Alternative proteins have gained popularity as consumers look for foods that are healthy, nutritious, and sustainable. Plant proteins, precision fermentation-derived proteins, cell-cultured proteins, algal proteins, and mycoproteins are the major types of alternative proteins that have emerged in recent years. This review addresses the major alternative-protein categories and reviews their definitions, current market statuses, production methods, and regulations in different countries, safety assessments, nutrition statuses, functionalities and applications, and, finally, sensory properties and consumer perception. Knowledge relative to traditional dairy proteins is also addressed. Opportunities and challenges associated with these proteins are also discussed. Future research directions are proposed to better understand these technologies and to develop consumer-acceptable final products.

Cultured meat in the European Union: Legislative context and food safety issues

The current food system, which is responsible for about one third of all global gas emissions, is considered one of the main causes of resource depletion. For this reason, scientific research is investigating new alternatives capable of feeding an ever-growing population that is set to reach 9-11 billion by 2050. Among these, cell-based meat, also called cultured meat, is one possible solution. It is part of a larger branch of science called cellular agriculture, whose goal is to produce food from individual cells rather than whole organisms, tracing their molecular profile. To date, however, cultured meat aroused conflicting opinions. For this reason, the aim of this review was to take an in-depth look at the current European legislative framework, which reflects a 'precautionary approach' based on the assumption that these innovative foods require careful risk assessment to safeguard consumer health. In this context, the assessment of possible risks made it possible not only to identify the main critical points during each stage of the production chain (proliferation, differentiation, scaffolding, maturation and marketing), but also to identify solutions in accordance with the recommendations of the European Food Safety Authority (EFSA). Further, the main challenges related to organoleptic and nutritional properties have been reviewed.. Finally, possible future markets were studied, which would complement that of traditional meat, implementing the offer for the consumer, who is still sceptical about the acceptance of this new product. Although further investigation is needed, the growing demand for market diversification and the food security opportunities associated with food shortages, as well as justifying the commercialisation of cultured meat, would present an opportunity to position cultured meat as beneficial.

A review: analysis of technical challenges in cultured meat production and its commercialization

The cultured meat technology has developed rapidly in recent years, but there are still many technical challenges that hinder the large-scale production and commercialization of cultured meat. Firstly, it is necessary to lay the foundation for cultured meat production by obtaining seed cells and maintaining stable cell functions. Next, technologies such as bioreactors are used to expand the scale of cell culture, and three-dimensional culture technologies such as scaffold culture or 3D printing are used to construct the three-dimensional structure of cultured meat. At the same time, it can reduce production costs by developing serum-free medium suitable for cultured meat. Finally, the edible quality of cultured meat is improved by evaluating food safety and sensory flavor, and combining ethical and consumer acceptability issues. Therefore, this review fully demonstrates the current development status and existing technical challenges of the cultured meat production technology with regard to the key points described above, in order to provide research ideas for the industrial production of cultured meat.

Programmable scaffolds with aligned porous structures for cell cultured meat

Porous scaffolds for cell cultured meat are currently limited in the food-grade material requirements, the cell adhesion, proliferation, and differentiation capacities, and the ignored appearance design. We proposed programmable scaffolds specially tailored for cell cultured meat. The scaffold with aligned porous structures was fabricated with the ice-templated directional freeze-drying of the food-grade collagen hydrogel. Due to the abundant tripeptide presence and well-aligned porous structures, the scaffold could not only provide sites for cell adhesion and proliferation, but also promote the oriented growth and differentiation of cells. The up-regulation of myogenic related genes, synthesis of myogenic related proteins and formation of matured myotubes furtherly proved the differentiation of cells on aligned scaffold. These characteristics would facilitate the traditional meat characteristics simulation of cell cultured meat in term of texture and microstructure. Meanwhile, patterned scaffolds were achievable as well with the help of mold-assisted ice templating, which would improve the people's interest, recognition, and acceptance of the tailored cell cultured meat. These characteristics indicate great application prospects of the proposed programmable scaffolds in cell cultured meat.

Trends in Hybrid Cultured Meat Manufacturing Technology to Improve Sensory Characteristics

The projected growth of global meat production over the next decade is attributed to rising income levels and population expansion. One potentially more pragmatic approach to mitigating the adverse externalities associated with meat production involves implementing alterations to the production process, such as transitioning to cultured meat, hybrid cultured meat, and meat alternatives. Cultured meat (CM) is derived from animal stem cells and undergoes a growth and division process that closely resembles the natural in vivo cellular development. CM is emerging as a widely embraced substitute for traditional protein sources, with the potential to alleviate the future strain on animal-derived meat production. To date, the primary emphasis of cultured meat research and production has predominantly been around the ecological advantages and ethical considerations pertaining to animal welfare. However, there exists substantial study potential in exploring consumer preferences with respect to the texture, color, cuts, and sustainable methodologies associated with cultured meat. The potential augmentation of cultured meat's acceptance could be facilitated through the advancement of a wider range of cuts to mimic real muscle fibers. This review examines the prospective commercial trends of hybrid cultured meat. Subsequently, the present state of research pertaining to the advancement of scaffolding, coloration, and muscle fiber development in hybrid cultured meat, encompassing plant-based alternatives designed to emulate authentic meat, has been deliberated. However, this discussion highlights the obstacles that have arisen in current procedures and proposes future research directions for the development of sustainable cultured meat and meat alternatives, such as plant-based meat production.

Cultivated meat manufacturing: Technology, trends, and challenges

The growing world population, public awareness of animal welfare, environmental impacts and changes in meat consumption leads to the search for novel approaches to food production. Novel foods include products with a new or specifically modified molecular structure, foods made from microorganisms, fungi, algae or insects, as well as from animal cell or tissue cultures. The latter approach is known by various names: "clean meat", "in vitro meat" and "cell-cultured" or "(cell-)cultivated meat". Here, cells isolated from agronomically important species are expanded ex vivo to produce cell biomass used in unstructured meat or to grow and differentiate cells on scaffolds to produce structured meat analogues. Despite the fast-growing field and high financial interest from investors and governments, cultivated meat production still faces challenges ranging from cell source choice, affordable expansion, use of cruelty-free and food-grade media, regulatory issues and consumer acceptance. This overview discusses the above challenges and possible solutions and strategies in the production of cultivated meat. The review integrates multifaceted historical, social, and technological insights of the field, and provides both an engaging comprehensive introduction for general interested and a robust perspective for experts.

Morphology-Based Prediction of Proliferation and Differentiation Potencies of Porcine Muscle Stem Cells for Cultured Meat Production

Inconsistent efficiency of cell production caused by cellular quality variations has become a significant problem in the cultured meat industry. In our study, morphological information on passages 5-9 of porcine muscle stem cells (pMuSCs) from three lots was analyzed and used as input data in prediction models. Cell proliferation and differentiation potencies were measured by cell growth rate and average stained area of the myosin heavy chain. Analysis of PCA and heatmap showed that the morphological parameters could be used to discriminate the differences of passages and lots. Various morphological parameters were analyzed, which revealed that accumulating time-course information regarding morphological heterogeneity in cell populations is crucial to predicting the potencies. Based on the 36 and 60 h morphological profiles, the best proliferation potency prediction model (R2 = 0.95, RMSE = 1.1) and differentiation potency prediction model (R2 = 0.74, RMSE = 1.2) were explored. Correlation analysis demonstrated that morphological parameters selected in models are related to the quality of porcine muscle stem cells.

Current technologies, regulation, and future perspective of animal product analogs - A review

The purpose of this study was to investigate the recent development of meat analog, industrialization, and the related legal changes worldwide. Summarizing the current status of the industrialization of meat analog, studies on plant-based meat, mycoprotein, and edible insects were mainly conducted to investigate their sensory properties (texture, taste, flavor, and color resembling meat), nutritional and safety evaluations, acquisition method of meat alternatives, and commercialization. Cultured meat is mainly studied for developing muscle satellite cell acquisition and support techniques or materials for the formation of structures. However, these technologies have not reached the level for active industrialization. Even though there are differences in the food categories and labeling between countries, it is common to cause confusion or to relay false information to consumers; therefore, it is important to provide accurate information. In this study, there were some differences in the food classification and food definition (labeling) contents for each country and state depending on the product shape or form, raw materials, and ingredients. Therefore, this study can provide information about the current research available on meat alternatives, improve regulation, and clarify laws related to the meat analog industry, which can potentially grow alongside the livestock industry.

Single-cell analysis of bovine muscle-derived cell types for cultured meat production

Cultured meat technologies leverage the proliferation and differentiation of animal-derived stem cells ex vivo to produce edible tissues for human consumption in a sustainable fashion. However, skeletal muscle is a dynamic and highly complex tissue, involving the interplay of numerous mono- and multinucleated cells, including muscle fibers, satellite cells (SCs) and fibro-adipogenic progenitors (FAPs), and recreation of the tissue in vitro thus requires the characterization and manipulation of a broad range of cell types. Here, we use a single-cell RNA sequencing approach to characterize cellular heterogeneity within bovine muscle and muscle-derived cell cultures over time. Using this data, we identify numerous distinct cell types, and develop robust protocols for the easy purification and proliferation of several of these populations. We note overgrowth of undesirable cell types within heterogeneous proliferative cultures as a barrier to efficient cultured meat production, and use transcriptomics to identify conditions that favor the growth of SCs in the context of serum-free medium. Combining RNA velocities computed in silico with time-resolved flow cytometric analysis, we characterize dynamic subpopulations and transitions between active, quiescent, and committed states of SCs, and demonstrate methods for modulation of these states during long-term proliferative cultures. This work provides an important reference for advancing our knowledge of bovine skeletal muscle biology, and its application in the development of cultured meat technologies.

Metabolic engineering of Bacillus amyloliquefaciens for efficient production of α-glucosidase inhibitor1-deoxynojirimycin

Owing to the feature of strong α-glucosidase inhibitory activity, 1-deoxynojirimycin (1-DNJ) has broad application prospects in areas of functional food, biomedicine, etc., and this research wants to construct an efficient strain for 1-DNJ production, basing on Bacillus amyloliquefaciens HZ-12. Firstly, using the temperature-sensitive shuttle plasmid T2 (2)-Ori, gene ptsG in phosphotransferase system (PTS) was weakened by homologous recombination, and non-PTS pathway was strengthened by deleting its repressor gene iolR, and 1-DNJ yield of resultant strain HZ-S2 was increased by 4.27-fold, reached 110.72 mg/L. Then, to increase precursor fructose-6-phosphate (F-6-P) supply, phosphofructokinase was weaken, fructose phosphatase GlpX and 6-phosphate glucose isomerase Pgi were strengthened by promoter replacement, moreover, regulator gene nanR was deleted, 1-DNJ yield was further increased to 267.37 mg/L by 2.41-fold. Subsequently, promoter of 1-DNJ synthetase cluster was optimized, as well as 5'-UTRs of downstream genes in synthetase cluster, and 1-DNJ produced by the final strain reached 478.62 mg/L. Last but not the least, 1-DNJ yield of 1632.50 mg/L was attained in 3 L fermenter, which was the highest yield of 1-DNJ reported to date. Taken together, our results demonstrated that metabolic engineering was an effective strategy for 1-DNJ synthesis, this research laid a foundation for industrialization of functional food and drugs based on 1-DNJ.

Expansion of bovine skeletal muscle stem cells from spinner flasks to benchtop stirred-tank bioreactors for up to 38 days

Introduction

Successful long-term expansion of skeletal muscle satellite cells (MuSCs) on a large scale is fundamental for cultivating animal cells for protein production. Prerequisites for efficient cell expansion include maintaining essential native cell activities such as cell adhesion, migration, proliferation, and differentiation while ensuring consistent reproducibility.

Method

This study investigated the growth of bovine MuSC culture using low-volume spinner flasks and a benchtop stirred-tank bioreactor (STR).

Results and discussion

Our results showed for the first time the expansion of primary MuSCs for 38 days in a bench-top STR run with low initial seeding density and FBS reduction, supported by increased expression of the satellite cell marker PAX7 and reduced expression of differentiation-inducing genes like MYOG, even without adding p38-MAPK inhibitors. Moreover, the cells retained their ability to proliferate, migrate, and differentiate after enzymatic dissociation from the microcarriers. We also showed reproducible results in a separate biological benchtop STR run.

Gellan gum-gelatin scaffolds with Ca2+ crosslinking for constructing a structured cell cultured meat model

As an emerging technology to obtain protein by culturing animal-derived cells in vitro, it is crucial to construct 3D edible scaffolds to prepare structured cell cultured meat products. In this study, a scaffold based on gellan gum (GG)-gelatin (Gel) was prepared and further cross-linked with Ca2+. FTIR confirmed the electrostatic interaction between GG and Gel and the ionic cross-linking of Ca2+ and carboxyl groups, and SEM images showed the porous structure of the scaffolds. The staining results showed that scaffolds with high concentrations of Ca2+ had higher biocompatibility than scaffolds with low concentrations of Ca2+ and non-crosslinked scaffolds, and scaffolds Ca2+-GG2-Gel3-0.5 adhered to more cells and were more conducive to cell spreading. The immunofluorescence staining, SEM images, Western blot, and RT-qPCR showed that the scaffolds supported the proliferation and myogenic differentiation of chicken skeletal muscle satellite cells (CSMSCs) and myotubes were formed on the scaffolds. Finally, the scaffolds were stained and fried after culturing. The results of the textural and chromatic analysis showed that the texture and color of the scaffolds were similar to fresh meat and meat products. These results showed that ionically crosslinked GG-Gel scaffolds are biocompatible and stable for structured cell cultured meat models.

Unlocking the potential of stem cells: Their crucial role in the production of cultivated meat

Cellular agriculture is an emerging research field of agribiotechnology that aims to produce agricultural products using stem cells, without sacrificing animals or cultivating crops. Cultivated meat, as a representative cellular product of cellular agriculture, is being actively researched due to global food insecurity, environmental, and ethical concerns. This review focuses on the application of stem cells, which are the seeds of cellular agriculture, for the production of cultivated meat, with emphasis on deriving and culturing muscle and adipose stem cells for imitating fresh meat. Establishing standards and safety regulations for culturing stem cells is crucial for the market entry of cultured muscle tissue-based biomaterials. Understanding stem cells is a prerequisite for creating reliable cultivated meat and other cellular agricultural biomaterials. The techniques and regulations from the cultivated meat industry could pave the way for new cellular agriculture industries in the future.

An Overview of Recent Progress in Engineering Three-Dimensional Scaffolds for Cultured Meat Production

Cultured meat is a new type of green, safe, healthy, and sustainable alternative to traditional meat that will potentially alleviate the environmental impact of animal farming and reduce the requirement for animal slaughter. However, the cultured meat structures that have been prepared lack sufficient tissue alignment. To create a product that is similar in texture and taste to traditional animal meat, muscle stem cells must be organized in a way that imitates the natural structure of animal tissue. Recently, various scaffold technologies and biomaterials have been developed to support the three-dimensional (3D) cultivation and organization of muscle stem cells. Hence, we propose an overview of the latest advancements and challenges in creating three-dimensional scaffolds for the biomanufacturing of cultured meat.

Bovine muscle satellite cells in calves and cattle: A comparative study of cellular and genetic characteristics for cultivated meat production

This study compared the cellular and genetic characteristics of bovine skeletal muscle satellite cells (SMSCs) from Hanwoo (a Korean native cattle breed), including calves and mature cattle. SMSCs were isolated using magnetic-activated cell sorting (MACS) from tissue samples of six Hanwoo (three calves and three mature cattle) using the CD29 antibody. Calves' SMSCs exhibited significantly faster growth rates than did those from cattle (P < 0.01), with a doubling time of 2.43 days. Genetic analysis revealed higher MyoD and Pax7 expression in SMSCs from calves during proliferation than in those from mature cattle (P < 0.001). However, FASN and PLAG1 expression levels were higher in mature cattle than in calves during both proliferation and differentiation (P < 0.001). These findings highlight the need for strategies to improve bovine muscle cell growth to produce competitive cultivated meat at a competitive price.

Repurposing biomedical muscle tissue engineering for cellular agriculture: challenges and opportunities

Cellular agriculture is an emerging field rooted in engineering meat-mimicking cell-laden structures using tissue engineering practices that have been developed for biomedical applications, including regenerative medicine. Research and industrial efforts are focused on reducing the cost and improving the throughput of cultivated meat (CM) production using these conventional practices. Due to key differences in the goals of muscle tissue engineering for biomedical versus food applications, conventional strategies may not be economically and technologically viable or socially acceptable. In this review, these two fields are critically compared, and the limitations of biomedical tissue engineering practices in achieving the important requirements of food production are discussed. Additionally, the possible solutions and the most promising biomanufacturing strategies for cellular agriculture are highlighted.

Soy Protein Amyloid Fibril Scaffold for Cultivated Meat Application

It is important to have sustainable and edible scaffolds to produce cultivated meat. In this research, three-dimensional (3D) porous scaffolds were developed by soy protein amyloid fibrils for cultivated meat applications. Food-safe biological and physical cross-linking methods using microbial transglutaminase and temperature-controlled water vapor annealing technique were employed to crosslink soy protein amyloid fibrils, resulting in the production of 3D scaffolds. The generated 3D scaffolds had pores with sizes ranging from 50 to 250 μm, porosities of 72-83%, and compressive moduli of 3.8-4.2 kPa, depending on the type of soy protein used in the process (β-conglycinin (7S), glycinin (11S) and soy protein isolate (SPI)). When present with pepsin, these scaffolds can degrade within an hour but remain stable in phosphate-buffered saline for at least 30 days. The soy protein amyloid fibril scaffolds enabled C2C12 mouse skeletal myoblasts proliferate and differentiate without adding cell adhesive proteins or other coatings. The results demonstrate the potential of abundant and inexpensive soy protein amyloid fibrils to be utilized as scaffold materials for cultivated meat in the food industry.

Preparation and Quality Evaluation of Cultured Fat

Cultured meat is rapidly developing as an emerging meat production technology. Adipose tissue plays an essential role in the flavor of meat products. In this study, cultured fat was produced by cultured adipose-derived stem cells (ADSCs) based on collagen in vitro, with a 3D model. The research showed that ADSCs could attach to collagen hydrogels and differentiate into mature adipocytes. Texture analysis demonstrated that the springiness, cohesiveness, and resilience of cultured fat were consistent with porcine subcutaneous fat. Moreover, 28 volatile organic compounds (VOCs) were detected by headspace gas chromatography-ion mobility spectrometry. The relative contents of 17 VOCs in cultured fat were significantly higher than porcine subcutaneous fat and empty collagen hydrogels, and the relative contents of 5 VOCs in cultured fat were not significantly different from porcine subcutaneous fat. These findings assert the promising application of cultured fat in cultured meat production.

Will cultured meat be served on Chinese tables? A study of consumer attitudes and intentions about cultured meat in China

This research investigates the attitudes and intentions of Chinese consumers about cultured "meat" (CM). We also investigate framing effects through the names used for these products ("cultured meat," "artificial meat," and "cell-based meat") and the effect of information provision. Of the 1532 consumers in our sample, most had not heard of "cultured meat" or "cell-based meat" before, although 70% had heard of "artificial meat". Around 44% of the participants indicated that they would be willing to try CM, and 32% would be likely to purchase it. Participants disliked the terms "cultured meat" and "cell-based meat" less than they disliked the term "artificial meat," although the latter was the most familiar to them. The provision of neutral information on the production process increased consumer support for CM, but the effect was limited. Prior knowledge and naming terms were strong predictors of attitudes and willingness to buy. A key implication is that stakeholders should cautiously apply framing strategies when introducing CM to the public.

Meat the challenge: Segmentation and profiling of Japanese beef mince and its substitutes consumers

Shifts in protein production methods are an emerging challenge toward realizing a sustainable society. This paper aims to examine preferences among Japanese consumers regarding attributes of beef mince and its substitutes, to develop consumer segments based on these preferences, and to explore the segment with higher acceptance of replacement from conventional products. This paper also aims to explain intersegment differences from consumer heterogeneity in human values, scientific literacy, and sociodemographic viewpoints for a deeper understanding of consumer behavior in each segment. The results of an online choice experiment involving 4421 consumers in Japan, using food labels on mince showed that Japanese-origin organic beef was associated with the highest utility among the five production methods mentioned. Five consumer segments were identified with latent class analysis: novelty accepters, generous customers, attribute-economy balancers, price-conscious, and conservatives, which vary in preference in choice behavior, sociodemographic, human values, and scientific literacy.

Comparisons between Plant and Animal Stem Cells Regarding Regeneration Potential and Application

Regeneration refers to the process by which organisms repair and replace lost tissues and organs. Regeneration is widespread in plants and animals; however, the regeneration capabilities of different species vary greatly. Stem cells form the basis for animal and plant regeneration. The essential developmental processes of animals and plants involve totipotent stem cells (fertilized eggs), which develop into pluripotent stem cells and unipotent stem cells. Stem cells and their metabolites are widely used in agriculture, animal husbandry, environmental protection, and regenerative medicine. In this review, we discuss the similarities and differences in animal and plant tissue regeneration, as well as the signaling pathways and key genes involved in the regulation of regeneration, to provide ideas for practical applications in agriculture and human organ regeneration and to expand the application of regeneration technology in the future.

Auxenochlorella pyrenoidosa extract supplementation replacing fetal bovine serum for Carassius auratus muscle cell culture under low-serum conditions

Cultured meat production requires large-scale cell proliferation in vitro with the supplementation of necessary media especially serum. This study investigated the capacity of Auxenochlorella pyrenoidosa extract (APE) to replace fetal bovine serum (FBS) for cell culture under low-serum conditions using Carassius auratus muscle (CAM) cells. Supplementation with APE and 5% FBS in the culture media significantly promoted the proliferation of CAM cells and increased the expression of MyoD in cells compared to that with 5% FBS through cell counting kit-8 and immunofluorescence staining assay. In addition, CAM cells in the media containing 5% FBS and APE could be continually cultured for 4 passages, and the cell number was 1.58 times higher than the counterpart without APE in long-term culture. Moreover, supplementation with APE realized large-scale culture on microcarriers under low-serum conditions, and more adherent cells were observed on microcarriers in 2% FBS supplemented with APE, compared with those in 2% FBS and 10% FBS without APE. These findings highlighted a potentially promising application of APE in muscle cell culture under low-serum conditions for cultured meat production.

- Invited Review - Gene-editing techniques and their applications in livestock and beyond

Genetic modification enables modification of target genes or genome structure in livestock and experimental animals. These technologies have not only advanced bioscience but also improved agricultural productivity. To introduce a foreign transgene, the piggyBac transposon element/transposase system could be used for production of transgenic animals and specific target protein-expressing animal cells. In addition, the clustered regularly interspaced short palindromic repeat-CRISPR associated protein 9 (CRISPR-Cas9) system have been utilized to generate chickens with knockout of G0/G1 switch gene 2 (G0S2) and myostatin, which are related to lipid deposition and muscle growth, respectively. These experimental chickens could be the invaluable genetic resources to investigate the regulatory pathways and mechanisms of improvement of economic traits such as fat quantity and growth. The gene-edited animals could also be applicable to the livestock industry.

Alternative dietary protein sources to support healthy and active skeletal muscle aging

To mitigate the age-related decline in skeletal muscle quantity and quality, and the associated negative health outcomes, it has been proposed that dietary protein recommendations for older adults should be increased alongside an active lifestyle and/or structured exercise training. Concomitantly, there are growing environmental concerns associated with the production of animal-based dietary protein sources. The question therefore arises as to where this dietary protein required for meeting the protein demands of the rapidly aging global population should (or could) be obtained. Various non-animal-derived protein sources possess favorable sustainability credentials, though much less is known (compared with animal-derived proteins) about their ability to influence muscle anabolism. It is also likely that the anabolic potential of various alternative protein sources varies markedly, with the majority of options remaining to be investigated. The purpose of this review was to thoroughly assess the current evidence base for the utility of alternative protein sources (plants, fungi, insects, algae, and lab-grown "meat") to support muscle anabolism in (active) older adults. The solid existing data portfolio requires considerable expansion to encompass the strategic evaluation of the various types of dietary protein sources. Such data will ultimately be necessary to support desirable alterations and refinements in nutritional guidelines to support healthy and active aging, while concomitantly securing a sustainable food future.

3D-Printed Prolamin Scaffolds for Cell-Based Meat Culture

Cultivating meat from muscle stem cells in vitro requires 3D edible scaffolds as the supporting matrix. Electrohydrodynamic (EHD) printing is an emerging 3D-printing technology for fabricating ultrafine fibrous scaffolds with high precision microstructures for biomedical applications. However, edible EHD-printed scaffolds remain scarce in cultured meat (CM) production partly due to special requirements with regard to the printability of ink. Here, hordein or secalin is mixed, which are cereal prolamins extracted from barley or rye, with zein to produce pure prolamin-based inks, which exhibit favorable printability similar to common polycaprolactone ink. Zein/hordein and zein/secalin scaffolds with highly ordered tessellated structures are successfully fabricated after optimizing printing conditions. The prolamin scaffolds demonstrated good water stability and in vitro degradability due to the porous fiber surface, which is spontaneously generated by culturing muscle cells for 1 week. Moreover, mouse skeletal myoblasts (C2C12) and porcine skeletal muscle satellite cells (PSCs) can adhere and proliferate on the fibrous matrix, and a CM slice is produced by culturing PSCs on prolamin scaffolds with high tissue similarity. The upregulation of myogenic proteins shows that the differentiation process is triggered in the 3D culture, demonstrating the great potential of prolamin scaffolds in CM production.

Scalable fabrication, compartmentalization and applications of living microtissues

Living microtissues are used in a multitude of applications as they more closely resemble native tissue physiology, as compared to 2D cultures. Microtissues are typically composed of a combination of cells and materials in varying combinations, which are dictated by the applications' design requirements. Their applications range wide, from fundamental biological research such as differentiation studies to industrial applications such as cruelty-free meat production. However, their translation to industrial and clinical settings has been hindered due to the lack of scalability of microtissue production techniques. Continuous microfluidic processes provide an opportunity to overcome this limitation as they offer higher throughput production rates as compared to traditional batch techniques, while maintaining reproducible control over microtissue composition and size. In this review, we provide a comprehensive overview of the current approaches to engineer microtissues with a focus on the advantages of, and need for, the use of continuous processes to produce microtissues in large quantities. Finally, an outlook is provided that outlines the required developments to enable large-scale microtissue fabrication using continuous processes.

Spontaneous immortalization of chicken fibroblasts generates stable, high-yield cell lines for serum-free production of cultured meat

Cellular agriculture could meet growing demand for animal products, but yields are typically low and regulatory bodies restrict genetic modification for cultured meat production. Here we demonstrate the spontaneous immortalization and genetic stability of fibroblasts derived from several chicken breeds. Cell lines were adapted to grow as single-cell suspensions using serum-free culture medium, reaching densities of 108 × 106 cells per ml in continuous culture, corresponding to yields of 36% w/v. We show that lecithin activates peroxisome proliferator-activated receptor gamma (PPARγ), inducing adipogenesis in immortalized fibroblasts. Blending cultured adipocyte-like cells with extruded soy protein, formed chicken strips in which texture was supported by animal and plant proteins while aroma and flavour were driven by cultured animal fat. Visual and sensory analysis graded the product 4.5/5.0, with 85% of participants extremely likely to replace their food choice with this cultured meat product. Immortalization without genetic modification and high-yield manufacturing are critical for the market realization of cultured meat.

A simplified and defined serum-free medium for cultivating fat across species

Cultivated meat is a promising technology with the potential to mitigate the ethical and environmental issues associated with traditional meat. Fat plays a key role in the meat flavor; therefore, development of suitable adipogenic protocols for livestock is essential. The traditional adipogenic cocktail containing IBMX, dexamethasone, insulin and rosiglitazone is not food-compatible. Here, we demonstrate that of the four inducers only insulin and rosiglitazone are necessary in both serum-free (DMAD) and serum-containing media, with DMAD outperforming FBS. Two glucocorticoid receptor activators, progesterone and hydrocortisone, found in DMAD and FBS, affect differentiation homogeneity, without playing an essential role in activating adipogenic genes. Importantly, this protocol leads to mature adipocytes in 3D culture. This was demonstrated in both media types and in four species: ruminant and monogastric. We therefore propose a simplified one-step adipogenic protocol which, given the replacement of rosiglitazone by a food-compatible PPARγ agonist, is suitable for making cultivated fat.

Sustainable Future Protein Foods: The Challenges and the Future of Cultivated Meat

Global pressure from consumers to improve animal welfare, and reduce microbiological risks or the use of antibiotics pose new challenges for the meat industry. Today's livestock production, despite many undertaken measures, is still far from being sustainable. This forced the need to work on alternative protein types that come from plants, insects, fungi, or cell culture processes. Due to some technical and legal barriers, cultivated meat is not present on the European market, however, in 2020 it was approved in Singapore and in 2022 in the USA. While the technology of obtaining cell cultures from animal muscles has been known and successfully practiced for years, the production of a stable piece of meat with appropriate texture, taste, and smell, is still a problem for several scientific groups related to subsequent companies trying to obtain the highest quality product, in line with the expectations of customers. Although the work on optimal cell meat production has been going on for years, it is still in an early stage, mainly due to several limitations that represent milestones for industrial production. The most important are: the culture media (without animal serum), which will provide an environment for optimal muscle development, natural or close to natural (but still safe for the consumer) stable scaffolds for growing cells. Here, we review the actual knowledge about the above-mentioned challenges which make the production of cellular meat not yet developed on an industrial scale.

Recent trends in bioartificial muscle engineering and their applications in cultured meat, biorobotic systems and biohybrid implants

Recent advances in tissue engineering and biofabrication technology have yielded a plethora of biological tissues. Among these, engineering of bioartificial muscle stands out for its exceptional versatility and its wide range of applications. From the food industry to the technology sector and medicine, the development of this tissue has the potential to affect many different industries at once. However, to date, the biofabrication of cultured meat, biorobotic systems, and bioartificial muscle implants are still considered in isolation by individual peer groups. To establish common ground and share advances, this review outlines application-specific requirements for muscle tissue generation and provides a comprehensive overview of commonly used biofabrication strategies and current application trends. By solving the individual challenges and merging various expertise, synergetic leaps of innovation that inspire each other can be expected in all three industries in the future.

iPSC Technology: An Innovative Tool for Developing Clean Meat, Livestock, and Frozen Ark

Induced pluripotent stem cell (iPSC) technology is an emerging technique to reprogram somatic cells into iPSCs that have revolutionary benefits in the fields of drug discovery, cellular therapy, and personalized medicine. However, these applications are just the tip of an iceberg. Recently, iPSC technology has been shown to be useful in not only conserving the endangered species, but also the revival of extinct species. With increasing consumer reliance on animal products, combined with an ever-growing population, there is a necessity to develop alternative approaches to conventional farming practices. One such approach involves the development of domestic farm animal iPSCs. This approach provides several benefits in the form of reduced animal death, pasture degradation, water consumption, and greenhouse gas emissions. Hence, it is essentially an environmentally-friendly alternative to conventional farming. Additionally, this approach ensures decreased zoonotic outbreaks and a constant food supply. Here, we discuss the iPSC technology in the form of a "Frozen Ark", along with its potential impact on spreading awareness of factory farming, foodborne disease, and the ecological footprint of the meat industry.

Consumers’ perception of cultured meat relative to other meat alternatives and meat itself: A segmentation study

Cultured meat is still under development but could possibly serve as a meat alternative. As a result, the acceptance and perception of cultured meat have received considerable attention in consumer research. However, only few comparisons to meat or meat alternatives have been made, which makes it unclear how cultured meat compares to these products. This is the first study to directly compare cultured meat to plant-based meat alternatives (PBMA), fish, insects, and conventional meat. Dutch consumers (n = 288) evaluated their perception and willingness to consume (WTC) patties made from the five sources listed above. Consumer segmentation based on the WTC ratings was performed, and the resulting clusters were compared in terms of their preferences, perception of cultured meat, and demographic and psychographic variables. To see if naming affected consumers' cultured meat perception, respondents were assigned to one of five naming conditions for cultured meat. The clusters analysis yielded three clusters, two of which showed moderate WTC cultured meat. The first cluster could be characterized as "meat lovers." Their WTC was strongest for conventional meat, followed by cultured meat, and tastiness was their main driver of WTC. The second cluster's preference was fish, followed by PBMA, with naturalness, safety, and tastiness being their drivers of WTC. The third cluster's highest WTC was for PBMA, followed by cultured meat. Among their drivers of WTC were healthiness, sustainability, and animal friendliness. Psychographic variables were highly valuable in explaining the clusters. Finally, no effects of naming for cultured meat were observed. PRACTICAL APPLICATION: The results contribute to the design of guidelines to promote different meat alternatives considering specific target populations.

A Review of the Challenges Facing Global Commercialization of the Artificial Meat Industry

The sustained growth of global meat consumption incentivized the development of the meat substitute industry. However, long-term global commercialization of meat substitutes faces challenges that arise from technological innovation, limited consumer awareness, and an imperfect regulatory environment. Many important questions require urgent answers. This paper presents a review of issues affecting meat substitute manufacturing and marketing, and helps to bridge important gaps which appear in the literature. To date, global research on meat substitutes focuses mainly on technology enhancement, cost reduction, and commercialization with a few studies focused on a regulatory perspective. Furthermore, the studies on meat substitute effects on environmental pollution reduction, safety, and ethical risk perception are particularly important. A review of these trends leads to conclusions which anticipate the development of a much broader market for the meat substitute industry over the long term, the gradual discovery of solutions to technical obstacles, upgraded manufacturing, the persistent perception of ethical risk and its influence on consumer willingness to accept meat substitutes, and the urgent need for constructing an effective meat substitute regulatory system.

Future foods: Design, fabrication and production through microfluidics

Many delicious foods are soft matter systems with health ingredients and unique internal structures that provide rich nutrition, unique textures, and popular flavors. Obtaining these special properties in food products usually requires specialized processes. Microfluidic technologies have been developed to physically manipulate liquids to produce a broad range of microunits, providing a suitable approach for precise fabrication of functional biomaterials with desirable interior structures in a bottom-up fashion. In this review, we present how microfluidics has been applied to produce gel-based structures and highlight their use in fabricating novel foods, focusing on, among others, cultured meat as a rapidly growing field in food industry. We first discuss the behaviors of food liquids in microchannels for fluidic structure design. Then, different types of microsized building blocks with specific geometries fabricated through microfluidics are introduced, including particles (point), fibers (line), and sheets (plane). These well-defined units can encapsulate or interact with cells, forming microtissues to construct meat products with desirable architectures. After that, we review approaches to scale up microfluidic devices for mass production of the hydrogel building blocks and highlight the challenges associated with bottom-up food production.

Harvest of quality-controlled bovine myogenic cells and biomimetic bovine muscle tissue engineering for sustainable meat production

Alternative technology for meat production holds the potential to alleviate ethical, environmental, and public health concerns associated with conventional meat production. Cultured meat produced using cell culture technology promises to become a viable alternative to animal-raised meat for the future of the food industry. In this study, biomimetic bovine muscle tissue was artificially fabricated from myogenic cells extracted from bovine meat. Our primary culture method relies on three key factors; a sequential digesting process, enzymatic treatment with pronase, and coating with laminin fragment on culture dishes. This method allows the efficient collection of large numbers of primary cells from bovine cheek meat, purifies the myogenic cells from the cell mixture, and then continuously grows the myogenic cells in vitro. In addition, using our "quality control" methods, we were able to determine the "cell quality", including the proliferative and differentiation capability in each step of the primary culture. Furthermore, to mimic native bovine meat, the quality-controlled bovine myogenic cells were cultured on a micropatterned thermoresponsive substrate stimulating a native-like aligned structure of cells, which were then transferred onto a fibrin-based gel. This gel-based culture environment promoted structural and functional maturation of the myogenic cells, resulting in the production of bovine muscle tissues with sarcomere structures, native-like membrane structures, and contractile ability. We believe that these biomimetic features of "tissue-engineered meat" are important for the production of future cultured meat, which will need native-like nutrients, texture and taste. Therefore, our meat production approach will provide a new platform to produce more native biomimetic tissue-engineered meat in the near future.

Strategies to improve meat-like properties of meat analogs meeting consumers' expectations

Due to environmental and ethical concerns, meat analogs represent an emerging trend to replace traditional animal meat. However, meat analogs lacking specific sensory properties (flavor, texture, color) would directly affect consumers' acceptance and purchasing behavior. In this review, we discussed the typical sensory characteristics of animal meat products from texture, flavor, color aspects, and sensory perception during oral processing. The related strategies were detailed to improve meat-like sensory properties for meat analogs. However, the upscaling productions of meat analogs still face many challenges (e.g.: sensory stability of plant-based meat, 3D scaffolds in cultured meat, etc.). Producing safe, low cost and sustainable meat analogs would be a hot topic in food science in the next decades. To realize these promising outcomes, reliable robust devices with automatic processing should also be considered. This review aims at providing the latest progress to improve the sensory properties of meat analogs and meet consumers' requirements.

Production of cultured meat from pig muscle stem cells

Cultured meat is meat for consumption produced in a more sustainable way. It involves cell harvesting and expansion, differentiation into myotubes, construction into muscle fibres and meat structuring. We isolated 5.3 × 104 porcine muscle stem cells from 1 g of neonatal pig muscle tissue. According to calculations, we need to expand muscle stem cells 106-107 times to produce 100 g or 1 kg of cultured meat. However, the cells gradually lost the ability to express stemness and mature muscle cell markers (PAX7, MyHC). To tackle this critical issue and maintain cell function during cell expansion, we found that long-term culture with (100 μM) l-Ascorbic acid 2-phosphate (Asc-2P) accelerated cell proliferation while preserving the muscle cell differentiation. We further optimized a scalable PDMS mold. Porcine muscle stem cells formed structurally-organized myotubes similar to muscle fibres in the mold. Asc-2P enhanced porcine muscle cells grown as 3D tissue networks that can produce a relatively large 3D tissue networks as cultured meat building blocks, which showed improved texture and amino acid content. These results established a realistic workflow for the production of cultured meat that mimics the pork meat structurally and is potentially scalable for industry.

A Narrative Review of Alternative Protein Sources: Highlights on Meat, Fish, Egg and Dairy Analogues

The research and development of alternatives to meat (including fish) and dairy products for human consumption have been increasing in recent years. In the context of these alternatives, there is a diversity of products such as tofu, tempeh, seitan, pulses, algae, seeds, nuts and insects. Apart from these, some products require new technical processes such as needed by milk drink alternatives, mycoprotein and meat, cheese and fish analogues. The aim of these analogues is to mimic the physical and organoleptic properties of animal origin products through fibrous composition and mix of ingredients from vegetable sources using adequate technology, which allow providing similar texture and flavor. Using a narrative approach to review literature, the objectives of this paper are to systematize the arguments supporting the adoption of meat, eggs and dairy alternatives, to identify the diversity of alternatives to these products on the market, including the related technological processes, and to project the challenges that the food industry may face soon. From a total of 302 scientific papers identified in databases, 186 papers were considered. More research papers on products associated with alternatives to milk were found. Nevertheless, there are products that need more research as analogues to meat and dairy products. A general scheme that brings together the main reasons, resources and challenges that the food industry faces in this promising area of alternatives to meat and dairy products is presented.