Tharos Krill Oil and Krill Meal Processing Technology

Advantages to Feed Manufacturers

Introduction

Tharos’ krill oil extraction process working in the North Arctic krill fishery, reinforced Tharos’ technology capability to obtain special human-grade and aqua-feed ingredients.

Jointly with Norwegian and Icelandic partners, a new net-free krill fishing method, first ever fishing region, and a plug-and-play processing plant, all working onboard a factory trawler, were put together. See the proof-of-concept on how this was achieved in this video.

This plant operated prior scaling-up the technology. It sourced special krill meal, and high-natural antioxidants and phospholipids enriched krill oils, 100% solvent-free extracted, targeting the pharma and dietary supplements industry. Special low-fat krill meals target the aqua-feed ingredient market.

The advantageous properties of South Antarctic krill meal and krill oil (Euphausia superba, Dana), are known by the aquafeed sector. And they must come from on-board factory trawlers processing them at-sea.

Manufacturing final products at-sea has become krill operators’ primary goal.

As described in one of Tharos’ krill meal reports, South Antarctic krill meal nutritional attributes makes it a unique feed ingredient for aqua-feeds due to krill meal’s protein quality, strong palatability, natural carotenoid pigment (as astaxanthin mainly), excellent lipids where Omega-3’s mainly bound to phospholipids, minerals profile and its chitin & chitosan constituent.

Krill meals’ negligible heavy metals amount of dioxins, PCB’s and heavy metals help this goal (Dimitri Sclabos, Aquafeed Advance in Processing & Formulation, vol VI issue IV, Dec. 2014).

In recent years, many studies have been conducted with different aquaculture species using Antarctic krill meal. Krill meal carotenoids pigment is considered as essential for the reproduction in aquatic species

In a feeding krill meal study with juvenile whiteleg shrimp, feed preference and grow response was evaluated, using a diet containing 3% fishmeal supplemented with either 3% of krill meal and another marine meal. Results indicated that krill meal acts as a powerful feeding effector and growth enhancer for whiteleg shrimp.

Current high-fat krill meal processing technologies follow the prevailing market drivers; manufactured at-sea on-board factory vessels, contain a (high) fat content circa 20-27%, and target oil extraction buyers.

This fat level is achievable in Antarctic’s high fat season (March – June) when raw krill contains >5% lipid content. This krill meal contains (low) protein content <55%, preferably used to extract phospholipids-enriched krill oils using solvents (chemical)-extraction models, in on-land factories.

The resulting oil goes to the growing Omega-3 pharma and dietary supplements market categories. At present, all krill oil extraction factories are not able to produce any krill oil avoiding the use of solvents, the ones forbidden to use at-sea.

As of Q1 2020, this high-fat krill meal is priced >USD3 per kilo FOB, a price reflects a matrix composed of high Chinese demand, on-board processing costs, the use of expensive food-grade antioxidants, costly packaging (laminated bags with oxygen barrier, vacuum packed and/or with N₂ barred), and expensive frozen storage and transportation.

High-fat krill meals are significantly reactive to auto-combustions and oxidation, negatively impacting final quality.

Factory trawlers that manufacture high-fat krill meals, for the current demanding Chinese krill oil extraction market for example, set the process to retain as much fat as possible in the resulting meal, securing that the lipids contained in the raw material emulsify with the protein, phospholipids acting as the emulsifying agent.

This high-fat krill meal (vs. traditional 18% max fat content meal), has some handling disadvantage. Also when manufacturing the feed, at the extrusion stage for example.

Handling these meals at the feed-manufacturing process, transportation through transportation screws, storage in silos, through mixers and tanks for example, does not “flow or run” well because of its poor flow properties, generating blockages and bridges.

The aquafeed sector needs krill meals with good nutritional quality, proteins >60%, (low) fat content of about 10-18%, good flow for an efficient transportation and stowage capacity, and competitively priced vs. vegetable and other low-cost ingredients. The later, although cheaper, its nutritional properties compromise feed quality.

Krill meals used for aqua-feeds are normally priced <USD2.5/kilo FOB. They used feed grade antioxidants, packed in propylene bags with black inner bags, or laminated foil bags with oxygen barrier, vacuum packed and/or N₂ barred.

Consequently, due to seasonal supply variations, feed manufacturers have only high-fat meals, with the inconveniences described, and protein < 55%.

Tharos patented krill oil extraction technology sources low-fat krill meals (<14%). This oil extraction process can be entirely carried out at-sea from fresh raw krill, or on-shore from frozen krill. The former operates on-board factory trawlers, 100% solvent-free, extracting two types of krill (enriched in phospholipids and tryglicerides), and high protein krill meal > 60%.

Tharos has two invention patents (IP1 and IP2) for a process that uses exclusively a physical-mechanical method as shown in the following schematic layout:

The Tharos process has been successfully operated on a pilot-size plant in Antarctic waters, and a commercial-sized process in the North Arctic krill fishery on-board a Norwegian-flagged trawler.

The process obtains; a) krill oil enriched in phospholipids (PL oil) >35% PL; b) krill oil rich in triglycerides and astaxanthin (TG oil) >1 000 ppm, and a krill meal with lipids <14% and proteins> 60%.

THAROS KRILL OIL

THAROS KRILL MEAL

Tharos and its Norwegian and Icelandic partners decided to scale-up the krill oil extraction process to a larger commercial-sized level, putting the current 300k/hr plant for sale.

The wealth of knowledge brought by our Norwegian partner NITG and Icelandic BRIM owner adds to the first ever net-free fishing system used on the Arctic krill fishery. A new krill oil quality profile is brought to market sustained by North Arctic krill species features.