Ulva sp. (Chlorophyta) intensive cultivation in a coastal area of the Eastern Mediterranean Sea.
Global population growth together with enhanced quality of life, in the era of climate change, is expected to cause doubling of the world’s food and energy demand by 2050. Furthermore, there is a strong interest in the replacement of fossil-based industries towards economical, environmentally friendly, and sustainable resource, for food, chemical and energy supply. Seaweed (marine macro-algae), which are among the most efficient photosynthetic organisms on earth, can provide a sustainable alternative source of plants biomass for protein and essential amino acids, carbohydrates; fibers; vitamins, lipids (polyunsaturated fatty acids), and minerals. Hence, seaweed can provide a profitable alternative of biomass for sustainable food and materials.
A team of researchers headed by Prof. Alexander Golberg at Tel Aviv University (TAU), have developed a novel set of energy efficient processing and fermentation technologies for conversion of seaweed biomass into foods, bio-chemicals, and biofuels. Energy efficient technologies, such as pulsed electric field (PEF), a non-thermal method, that involves the use of short high voltage pulses, for wet biomass extraction process.
The lab has developed an economically viable method for intensive cultivation of seaweed in proprietary offshore cages. Furthermore, an improved extraction device and methods for extraction of protein and carbohydrate from seaweed, has been developed. The methods, such as pulsed electric field, hydrothermal treatments, fermentation, enzyme digestion, and green solvents, allows for an alternative green option in synthesizing fundamental compounds for food, chemical and energy industry.
The group has shown improved extraction and processing efficienc,higher protein and carbohydrate yields and quality, low processing temperature, and efficient energy utilization.
Furthermore, the group has shown that non-conventional carbon sources, such as seaweed, are sustainable alternatives for large-scale production of bioplastic (PHAs).
Increase in seaweed growth rates in offshore cages, achieved by the combined effect of tumbling and mixing of the algae using influxes of water, nutrients, and air. The experimental system was tested in a shallow coastal area, show a daily growth rate of 19.2%, areal productivity of 34 g dry weight (DW)/ day, and volumetric yields of 38 g DW/day per cubic meter.
Traditional biomass processing technologies use heat for drying and thermochemical processes for biomass decomposition. Prof. Alexander Golberg’s group has developed novel pulsed electric field extraction technologies (from seaweed). The use of pulsed electric fields technology enables to preserve the natural structure and function of compounds, which is unachievable using standard chemical or thermal extraction methods.
Thus, a continuous process for extraction of proteins, carbohydrates and other phytochemical from seaweed without compromising their structure by pulsed electric fields and specific fluidized bed reactor that allows for direct separation of products. In addition, a Capacitor Charging Power Supplies was developed. The instrument allows for a precise control which is important to reduce energy demand and utilization of solvents, on large-scale systems such as food and waste processing.
Applications and Advantages
- Reduced material cost (reduce the use of chemicals, higher yields)
- Lower waste treatment cost (minimizes hazardous waste formation.)
- Decreased energy costs.
- Excellent yields
- Food – Protein, Fibers.
- Food pigments
- Cosmetics and fragrances