In vitro Insect Fat Cultivation for Cellular Agriculture Applications.

Cell-cultured fat could provide important elements of flavor, nutrition, and texture to enhance the quality and therefore expand consumer adoption of alternative meat products. In contrast to cells from livestock animals, insect cells have been proposed as a relatively low-cost and scalable platform for tissue engineering and muscle cell-derived cultured meat production. Furthermore, insect fat cells have long been cultured and characterized for basic biology and recombinant protein production but not for food production. To develop a food-relevant approach to insect fat cell cultivation and tissue engineering, Manduca sexta cells were cultured and induced to accumulate lipids in 2D and 3D formats within decellularized mycelium scaffolding. The resultant in vitro fat tissues were characterized and compared to in vivo fat tissue data by imaging, lipidomics, and texture analyses. The cells exhibited robust lipid accumulation when treated with a 0.1 mM soybean oil emulsion and had "healthier" fat profiles, as measured by the ratio of unsaturated to saturated fatty acids. Mycelium scaffolding provided a simple, food-grade approach to support the 3D cell cultures and lipid accumulation. This approach provides a low-cost, scalable, and nutritious method for cultured fat production.

3D porous scaffolds from wheat glutenin for cultured meat applications.

Scaffolds suitable for use in food products are crucial components for the production of cultured meat. Here, wheat glutenin, an inexpensive and abundant plant-based protein, was used to develop 3D porous scaffolds for cultured meat applications. A physical cross-linking method based on water annealing was developed for the fabrication of porous glutenin sponges and fibrous aligned scaffolds. The pore sizes ranged from 50 to 250 µm, with compressive modulus ranges from 0.5 to 1.9 kPa, depending on the percentage of glutenin (2%-5%) used in the process. The sponges were stable in PBS with refrigeration for at least six months after water annealing. The glutenin scaffolds supported the proliferation and differentiation of C2C12 mouse skeletal myoblasts and bovine satellite cells (BSCs) without the need to add specific cell adhesive proteins or other coatings. The low cost and food safe production process avoided the use of toxic cross-linkers and animal-derived extracellular matrix (ECM) coatings, suggesting that this as approach is a promising system for scaffolds useful in cultivated meat applications.

Perspectives on scaling production of adipose tissue for food applications.

With rising global demand for food proteins and significant environmental impact associated with conventional animal agriculture, it is important to develop sustainable alternatives to supplement existing meat production. Since fat is an important contributor to meat flavor, recapitulating this component in meat alternatives such as plant based and cell cultured meats is important. Here, we discuss the topic of cell cultured or tissue engineered fat, growing adipocytes in vitro that could imbue meat alternatives with the complex flavor and aromas of animal meat. We outline potential paths for the large scale production of in vitro cultured fat, including adipogenic precursors during cell proliferation, methods to adipogenically differentiate cells at scale, as well as strategies for converting differentiated adipocytes into 3D cultured fat tissues. We showcase the maturation of knowledge and technology behind cell sourcing and scaled proliferation, while also highlighting that adipogenic differentiation and 3D adipose tissue formation at scale need further research. We also provide some potential solutions for achieving adipose cell differentiation and tissue formation at scale based on contemporary research and the state of the field.

Plant-based and cell-based approaches to meat production.

Advances in farming technology and intensification of animal agriculture increase the cost-efficiency and production volume of meat. Thus, in developed nations, meat is relatively inexpensive and accessible. While beneficial for consumer satisfaction, intensive meat production inflicts negative externalities on public health, the environment and animal welfare. In response, groups within academia and industry are working to improve the sensory characteristics of plant-based meat and pursuing nascent approaches through cellular agriculture methodology (i.e., cell-based meat). Here we detail the benefits and challenges of plant-based and cell-based meat alternatives with regard to production efficiency, product characteristics and impact categories.

Prospects and challenges for cell-cultured fat as a novel food ingredient.

BACKGROUND: In vitro meat production has been proposed as a solution to environmental and animal welfare issues associated with animal agriculture. While most academic work on cell-cultured meat has focused on innovations for scalable muscle tissue culture, fat production is an important and often neglected component of this technology. Developing suitable biomanufacturing strategies for adipose tissue from agriculturally relevant animal species may be particularly beneficial due to the potential use of cell-cultured fat as a novel food ingredient. SCOPE AND APPROACH: Here we review the relevant studies from areas of meat science, cell biology, tissue engineering, and bioprocess engineering to provide a foundation for the development of in vitro fat production systems. We provide an overview of adipose tissue biology and functionality with respect to meat products, then explore cell lines, bioreactors, and tissue engineering strategies of potential utility for in vitro adipose tissue production for food. Regulation and consumer acceptance are also discussed. KEY FINDINGS AND CONCLUSIONS: Existing strategies and paradigms are insufficient to meet the full set of unique needs for a cell-cultured fat manufacturing platform, as tradeoffs are often present between simplicity, scalability, stability, and projected cost. Identification and validation of appropriate cell lines, bioprocess strategies, and tissue engineering techniques must therefore be an iterative process as a deeper understanding of the needs and opportunities for cell-cultured fat develops.

In Vitro Insect Muscle for Tissue Engineering Applications.

Tissue engineering is primarily associated with medical disciplines, and research has thus focused on mammalian cells. For applications where clinical relevance is not a constraint, it is useful to evaluate the potential of alternative cell sources to form tissues in vitro. Specifically, skeletal muscle tissue engineering for bioactuation and cultured foods could benefit from the incorporation of invertebrate cells because of their less stringent growth requirements and other versatile features. Here, we used a Drosophila muscle cell line to demonstrate the benefits of insect cells relative to those derived from vertebrates. The cells were adapted to serum-free media, transitioned between adherent and suspension cultures, and manipulated with hormones. Furthermore, we analyzed edible scaffolds to support cell adhesion and assayed cellular protein and minerals to evaluate nutrition potential. The insect muscle cells exhibited advantageous growth patterns and hold unique functionality for tissue engineering applications beyond the medical realm.