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.

Effect of p38 inhibitor on the proliferation of chicken muscle stem cells and differentiation into muscle and fat.

OBJECTIVE: Inhibiting the p38 mitogen-activated protein kinase (MAPK) signaling pathway delays differentiation and increases proliferation of muscle stem cells in most species. Here, we aimed to investigate the effect of p38 inhibitor (p38i) treatment on the proliferation and differentiation of chicken muscle stem cells. METHODS: Chicken muscle stem cells were collected from the muscle tissues of Hy-line Brown chicken embryos at embryonic day 18, then isolated by the preplating method. Cells were cultured for 4 days in growth medium supplemented with dimethyl sulfoxide or 1, 10, 20 µM of p38i, then subcultured for up to 4 passages. Differentiation was induced for 3 days with differentiation medium. Each treatment was replicated 3 times. RESULTS: The proliferation and mRNA expression of paired box 7 gene and myogenic factor 5 gene, as well as the mRNA expression of myogenic differentiation marker gene myogenin were significantly higher in p38i-treated cultures than in control (p<0.05), but immunofluorescence staining and mRNA expression of myosin heavy chain (MHC) were not significantly different between the two groups. Oil red O staining of accumulated lipid droplets in differentiated cell cultures revealed a higher lipid density in p38i-treated cultures than in control; however, the expression of the adipogenic marker gene peroxisome proliferator activated receptor gamma was not significantly different between the two groups. CONCLUSION: p38 inhibition in chicken muscle stem cells improves cell proliferation, but the effects on myogenic differentiation and lipid accumulation require additional analysis. Further studies are needed on the chicken p38-MAPK pathway to understand the muscle and fat development mechanism.

Mechanism of improving emulsion stability of emulsion-type sausage with oyster mushroom (Pleurotus ostreatus) powder as a phosphate replacement.

This research evaluated the potentiality of oyster mushroom powder (OMP) as a phosphate alternative by improving emulsion stability of emulsion-type sausage. Sausage without phosphate (NC), with 0.2% sodium triphosphate (PC), and with 1 and 2% OMP (M1 and M2) were prepared. The OMP addition improved the physicochemical properties of sausage, effectively prevented lipid oxidation, and delayed the growth of aerobic bacteria during 28 days of cold storage compared to NC. The M1 and M2 improved the emulsion stability similar to PC. M2 had the highest water holding capacity and apparent viscosity and the lowest cooking loss (P < 0.05). The addition of OMP resulted in different textural characteristics from that of phosphate due to the formation of emulsion structures randomly entrapped by filament-like components, which were derived from polysaccharides or the conjugates between polysaccharides and proteins. According to the results of this study, emulsion stability promoted by OMP was mainly due to the polysaccharides, which are involved in enhancing viscosity and steric hindrance.

Effect of Penicillium candidum and Penicillium nalgiovense and their combination on the physicochemical and sensory quality of dry-aged beef.

This study was designed to investigate the effect of starter culture on the improvement of physicochemical and sensory properties of dry-aged beef. Penicillium nalgiovense and Penicillium candidum were used as single starter cultures and mixed suspensions (1:1) to determine the effect of mixed starter culture. Starter cultures were spray-inoculated on the surface of beef samples, and samples were dry-aged for 0, 7, 10, 14, and 21 days. Dry-aged samples were then analyzed for microbial population, physicochemical properties (pH, water content, and color), proteolytic activity on sarcoplasmic and myofibrillar proteins, and flavor compounds (free amino acids, nucleotides, and volatile compounds). The microbial activities of starter cultures affected the physicochemical traits and enhanced sensory quality. Penicillium candidum particularly influenced proteolytic activity and volatile compounds, whereas P. nalgiovense affected free amino acid and nucleotide content, with the most significant effect on day 7. Combination of the two strains resulted in different patterns when compared to the single strains. Therefore, the inoculation of mold starter cultures significantly affected the physicochemical properties and improved the sensory qualities of dry-aged beef, and the effect differed between single and mixed strains.

Determining the Optimal Cooking Time for Cooking Loss, Shear Force, and Off-Odor Reduction of Pork Large Intestines.

The objective of this study was to determine the optimal cooking time by considering the cooking loss, shear force, and off-odor reduction of pork large intestines. Commercial pork large intestines were purchased, quartered perpendicularly, and cooked in boiling water for 40, 120, 180, and 240 min. Cooking loss of the samples increased after 240 min of cooking (10.92, p<0.05) while shear force value was lower at 240 min (4.45) compared to that at other cooking times (p<0.001). The amount of major volatile organic compounds showed a decreasing trend with increasing cooking time. In particular, the amount of methyl pentanoate (17,528.71) and methyl isobutyrate (812.51), compounds with a relatively low odor threshold, decreased significantly after 120 min of cooking and no change was observed thereafter (p<0.05). In addition, the amount of 2-pentanol (3,785.65) and 1-propanol (622.26), possibly produced by lipid oxidation, significantly decreased at the same cooking time (p<0.001). In the principal component analysis, only the 40 min cooking time was significantly different from other cooking time by high amounts of 1-propanol, 2-pentanol, and methyl isobutyrate. In conclusion, in the present study, the optimal cooking time for pork large intestines was 120 min in terms of off-odor reduction, cooking loss, and shear force.