Production of Yeast Cell Biomass, Single Cell Oil and Polysaccharides from Mizithra Second Cheese

Garibel Valikeh^*
*Correspondence: Garibel Valikeh, Department of Food Science and Human Nutrition, Agricultural University of Athens, Athens, Greece, Email:

Introduction

The dairy industry generates a significant amount of whey as a byproduct, which often goes underutilized. Mizithra second cheese whey, a byproduct of the Greek cheese-making process, has the potential to be a valuable resource for the production of yeast cell biomass, single-cell oil, and polysaccharides. This article explores the various aspects of utilizing Mizithra second cheese whey as a substrate for yeast fermentation, the extraction of single-cell oil and polysaccharides, and the potential applications of these products in the food and biotechnology industries. The sustainable conversion of whey into high-value products presents an exciting opportunity for both waste reduction and economic development [1].

The dairy industry plays a crucial role in the global food production chain, producing a wide array of products, including various cheeses, yogurts, and milk. However, the cheese-making process generates a substantial amount of whey as a byproduct, which can be a challenging waste stream to manage. Whey is rich in lactose, proteins, and minerals, making it a potential resource for the production of various high-value bioproducts. This article focuses on the utilization of Mizithra second cheese whey for the production of yeast cell biomass, single-cell oil, and polysaccharides. Mizithra second cheese is a popular Greek cheese traditionally made from sheep's or goat's milk. During the cheese-making process, whey is produced as a byproduct. Whey derived from Mizithra cheese production is known as Mizithra second cheese whey. It contains lactose, proteins, and minerals, which are valuable substrates for microbial fermentation. One of the primary applications of Mizithra second cheese whey is its use as a substrate for yeast fermentation. Yeast is a versatile microorganism widely employed in various industrial processes. In this case, yeast can utilize the lactose present in whey as a carbon source and convert it into valuable biomass. The choice of yeast strain is critical for the efficient conversion of lactose into biomass. S. cerevisiae commonly used in the baking and brewing industries, is a suitable candidate due to its ability to ferment lactose. Proper fermentation conditions, including temperature, pH, and aeration, are essential for optimizing yeast growth. Yeast cells multiply rapidly in Mizithra second cheese whey, leading to the production of a high-density yeast biomass. In some cases, additional nutrients such as nitrogen and vitamins may be required to support yeast growth and enhance biomass production [2].

Description

The yeast cell biomass obtained from Mizithra second cheese whey can serve as a valuable source of protein and other bioactive compounds, making it suitable for various applications in the food and feed industries. Apart from yeast cell biomass, another valuable product that can be obtained from yeast fermentation of Mizithra second cheese whey is Single-Cell Oil (SCO). SCO is a term used to describe the lipids (fats) produced by microorganisms, primarily yeasts and fungi, when grown on suitable substrates. The lipid content of yeast cells can be significant, making them a potential source of oil for various applications. Under specific fermentation conditions, yeast cells accumulate lipids as an energy storage mechanism. This is particularly true when yeast cells are subjected to stress, such as nitrogen limitation [3].

After yeast fermentation, the cells can be harvested, and the lipids can be extracted using various methods, including solvent extraction, supercritical fluid extraction, and enzymatic methods. These methods yield crude oils that can be further refined for various applications. The composition of SCO depends on the yeast strain, fermentation conditions, and the substrate used. It can contain a mixture of saturated and unsaturated fatty acids, which are valuable for various industrial and nutritional applications. SCO obtained from Mizithra second cheese whey can find applications in biodiesel production, as a source of specialty lipids in the food industry, and as a nutritional supplement due to its high omega-3 fatty acid content. Polysaccharides are long-chain carbohydrates made up of repeating sugar units. Yeasts have the ability to produce Extracellular Polysaccharides (EPS) when grown on certain substrates. Mizithra second cheese whey can serve as a suitable substrate for EPS production. Certain yeast strains can produce EPS as part of their natural metabolism. EPS production is influenced by factors such as carbon and nitrogen sources, pH, and temperature.

After fermentation, the yeast cells can be separated from the fermentation broth, and the EPS can be extracted and purified. EPS have a variety of potential applications in the food, pharmaceutical, and cosmetic industries. The type and properties of EPS produced depend on the yeast strain and fermentation conditions. Common yeast-derived EPS include beta-glucans and mannans, which have known health benefits and functional properties. The production of yeast cell biomass, single-cell oil, and polysaccharides from Mizithra second cheeseIt allows for the conversion of a waste byproduct (whey) into high-value products, reducing environmental pollution and waste disposal costs. Mizithra second cheese whey is a readily available and cost-effective substrate for yeast fermentation, making it a sustainable resource. The obtained products (yeast biomass, SCO, and EPS) have a wide range of applications in various industries, including food, biotechnology, and biofuels.

Some of the products, such as yeast-derived beta-glucans, have proven health benefits, including immune system modulation and cholesterol reduction.

The production of these valuable bioproducts can create economic opportunities for dairy producers and biotechnology companies, contributing to regional development. While the production of yeast cell biomass, single-cell oil, and polysaccharides from Mizithra second cheese whey holds great promise, several challenges and future research directions should be considered. Identifying and developing yeast strains with enhanced capabilities for lactose fermentation, lipid accumulation, and EPS production is crucial for improving yields. Fine-tuning fermentation conditions and downstream processing methods can enhance product yields and quality. Proper disposal or utilization of residual fermentation byproducts and waste streams must be addressed to ensure an environmentally sustainable process. Promoting the use of these novel bioproducts in various industries may require marketing efforts and consumer education. As these products find their way into the food and pharmaceutical markets, regulatory compliance and safety assessments will become increasingly important [4,5].

Conclusion

The utilization of Mizithra second cheese whey as a substrate for yeast fermentation represents an innovative approach to waste valorization in the dairy industry. The production of yeast cell biomass, single-cell oil, and polysaccharides from this byproduct offers numerous economic and environmental benefits. With ongoing research and development efforts focused on strain optimization, process refinement, and market acceptance, the conversion of whey into high-value bioproducts holds tremendous potential for sustainable industrial applications. As the demand for alternative, sustainable sources of biomass and bioactive compounds continues to grow, Mizithra second cheese whey could become a valuable resource in the emerging bioeconomy.

Acknowledgement

None.

Conflict of Interest

There is no conflict of interest by author.

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