Kenya is a net importer of agar and alginate based on recent government statistics, although it may have the potential to be self-sufficient or even an exporter of these phycocolloids. There is little information on carrageenan importation into Kenya since government statistics incorporate it as agar. Seaweeds are relatively unimportant in the Kenyan diet since they are consumed rarely by coastal people. A survey of 15 sites along of the Kenyan coast evaluated the potential for harvesting seaweeds and for establishing seaweed farms. Gracilaria appears to comprise the bulk of the low grade agar import, even though local species of this genus are widely distributed along the Kenyan coast. Major populations of Gelidium may be a potential source of high quality bacteriological grade agar. Eucheuma may be farmed locally to support the increasing local and regional demands for carrageenan. Recommendations for a national program of management and production for Kenya will be discussed.
Digital library
-
-
Background Due to its short lifetime food packaging leads to a rapid accumulation of plastic in our surroundings and thereby also has a huge impact on environmental pollution. To reduce these effects and create a more sustainable approach towards food packaging biodegradable and biobased polymers have been developed and are emerging on the market. Scope and approach This review provides the current state of research regarding active packaging and the incorporation of seaweed into food packaging. Further, it summarises the resulting consequences of the seaweed incorporation on mechanical, physical, thermal, antioxidant, antimicrobial and chemical properties, as well as the release of active compounds to show the advantages of the polysaccharides as well as possible shortcomings in current research. Key findings and conclusions To improve these polymers regarding their mechanical, thermal and antimicrobial properties etc. a variety of polysaccharides such as seaweeds can be used. They not only lead to an increase in hydrophilicity and improved mechanical properties such as tensile strength and elongation at break, but also create the possibility of using it as active packaging. This can be achieved due to the naturally occurring antioxidant properties in seaweed, which can minimise lipid oxidation and thereby increase the shelf life and nutritional value of food as well as reduce free radicals which might have a carcinogenic, mutagenic or cytotoxic effect. Some seaweeds such as H. elongate have also proven to inhibit the growth of gram-positive and gram-negative bacteria, meaning that they could possibly be used as antimicrobial packaging.
-
Considering the importance of seaweeds for the development of sustainable and innovative food products, this study aimed to characterize the impact of hydrothermal processing on iodine, sodium, potassium, selenium, and arsenic concentrations of four seaweed species (S. latissima, L. digitata, U. pinnatifida, and C. crispus) and on the associated health risks-benefits for consumers. These elements revealed a common pattern for leachable fractions of iodine, total arsenic, and selenium: L. digitata ≥ S. latissima > C. crispus > U. pinnatifida after rehydration and boiling during different periods. The behavior for sodium was: S. latissima > L. digitata > C. crispus > U. pinnatifida, and for potassium: U. pinnatifida > L. digitata > S. latissima > C. crispus. Generally, the species that attained more significant losses were S. latissima and L. digitata. A health-relevant sodium/potassium ratio below 0.7 was found for all species except for U. pinnatifida. In some species, the risk-benefit analysis revealed that high iodine and arsenic levels might promote risks for consumption, even after 20 min boiling, but 5 g of processed U. pinnatifida could contribute to adequate iodine, sodium, potassium, and selenium intakes for all population groups. Standardized processing treatments of seaweeds can open new opportunities for the sector.
-
Seaweeds-products, processing and utilization Marine macroalgae which are popularly termed as Seaweeds belong to the primitive group of nonflowering plants known as Thallophyta. They are autotrophic plants and grow in the intertidal and subtidal regions of the sea.
-
Seaweeds have a long tradition in Asian cuisine. In Canada and US, seaweed consumption is mostly limited to sushi and other imported Asian dish. However, seaweeds are well recognized for their richness in several nutrients such as fiber, protein and minerals. But what is limiting seaweed and seaweed derived ingredients utilization in home cooking? Finding fresh seaweeds within inland cities is one limiting step but also the seaweed marketing need to propel the image that seaweed are not only nutritive but can bring flavor and texture in cuisine dish. With the rise of TV cooking shows, blogs and online recipes hosted by several renowned chefs, it is now time to bring seaweed in the spotlight. The aim of this review is to look at seaweeds to support a wider use in culinary applications for their nutritional contribution but also from a sensory perspective.
-
Seaweeds, otherwise known as marine algae are primitive non-flowering photosynthetic macrophytes occurring in tidal regions of seas and oceans that occupy 71% of the globe and they are natural renewable resources. Green, brown and red seaweeds are generally distributed in the intertidal, tidal and subtidal regions respectively. Seaweed production through aquaculture in the world was 11.66, 16.83 and 19.90 million tons (fresh) in 2002, 2008 and 2010 respectively and in 2012 it was 23.78 million tons (fresh). Kappaphycus alvarezii production in the world was 1,83,000 tons (dry) in 2010 while it was 1, 490 tons (fresh) during the same period in India. Seaweeds formed part of human life from time immemorial and served as food, besides their use as feed, fodder and manure. Some of the edible seaweeds include species of Porphyra, Palmaria, Undaria, Laminaria, Monostroma and Caulerpa and possess desirable quantities of proteins, carbohydrates, fibre, minerals and vitamins, besides having biological compounds to combat diseases. Ascophyllum sp, Macrocystis sp, Laminaria sp, Alaria sp, Palmaria sp and Pelvetia sp are some of seaweeds used as fodder. Seaweeds are the only natural source for hytochemicals viz; agar, algin and carrageenan which have wide applications in various ways in day to day life of human beings. Species of Gelidium, Gracilaria, Pterocladia, Gelidiella, Ahenpeltia and Acanthopeltis are some agarophytes, while those of Laminaria, Macrocystis, Ascophyllum, Durvillea, Ecklonia and Sargassum are some alginophytes. Carrageenophytes include species of Chondrus, Gigartina, Sarcothalia, Eucheuma and Kappaphycus. The alginophytes mentioned here also serve as manure because they contain macronutrients (N, P, K, Ca, Mg, S), micronutrients (Zn, Cu, Mn) and growth regulators (auxins, gibberlins, cytokinins) necessary for plant growth.
-
Seaweeds is an impressively compre- hensive and well-organized compila- tion of information about the ecology of macroalgae and seagrasses. This one-author treatise is a re-edited En- glish-language edition of Meeresbot- anik (Luning 1985). It has been up- dated in all areas and expanded to include more paleoecology. A great deal is accomplished in the 370 pages of text, which has been well trans- lated. The book is cleverly organized, so that it may be read from cover to cover with little repetition or it can be used as a reference. The subjects are covered from the general to the spe- cific, according to a biogeographical outline, and the book ends with a 100-page discussion of the experi- mental data that help explain the mechanisms of adaptation that sea- weeds employ.
-
High growth rates and temporal or spatial opportunism are considered central to the success of filamentous algae, in particular for escaping or minimising the effects of herbivory. However, the role of chemical defences in filamentous algae has received far less attention. We investigated possible chemical feeding deterrence by filamentous red algae that have conspicuous cellular inclusions (Asparagopsis armata, Anotrichium tenue and Balliella amphiglanda) and 2 others without inclusions (Callithamnion korfense and Ulva sp.). The 3 algae with cellular inclusions were consumed at lower rates by a generalist amphipod, Hyale nigra, than the other 2 algae. To determine the potential role of chemical defences for A. armata, we conducted tests against herbivores using algae in which the production of halogenated metabolites was manipulated. This manipulation had no effect on carbon and nitrogen values of the algae, and allowed us to directly test the role of algal secondary metabolites in defence against herbivores without using artificial diets. Bromide (+) algae (with halogenated metabolites) deterred grazing by 2 mesograzers (Hyale nigra and juvenile abalone Haliotis rubra), which consumed up to 4 times more bromide (–) (metabolite-free) algae than bromide (+) algae. Juveniles of the sea hare Aplysia parvula were not deterred by the chemical defences in bromide (+) A. armata. In field assays, artificial diets containing a crude extract of A. armata were also active against herbivores. Although functional form models typically predict that tolerance—not resistance—should be the key defensive strategy for marine algae with simple architecture, this study demonstrates that resistance traits may also be important and more broadly utilised in filamentous species.
-
PDF of pictures of seaweed used as seaweed noodle.
-
Nets in traditional Porphyra mariculture are seeded with conchospores derived from the conchocelis phase, and spend a nursery period in culture tanks or calm coastal waters until they reach several centimeters in length. Some species of Porphyra can regenerate the foliose phase directly through asexual reproduction, which suggests that the time, infrastructure, and costs associated with conchocelis culture might be avoided by seeding nets with asexual spores. Here, we present work from a short-term mariculture study using nets seeded with asexual spores (neutral spores) of a native Maine species of Porphyra. Porphyra umbilicalis (L.) Kutzing was selected for this proof of concept research because of its reproductive biology, abundance across seasons in Maine, and evidence of its promise as a mariculture crop. We studied the maturation, release, and germination of the neutral spores to develop an appropriate seeding protocol for nets, followed by development of a nursery raceway to provide an easily manipulated environment for the seeded nets. Neutral spores were produced throughout the year on the central Maine coast,however, there was a temporal variability in the number and survival of released neutral spores, depending upon thallus position in the intertidal zone. Small thalli were strictly vegetative, but most thalli reproduced by neutral spores- sexual reproduction was absent. Neutral spores germinated quickly at 10 and 15 'C, but germination was delayed at 5 degrees C. Unlike some algal zygotes and spores, neutral spores of R umbilicalis required light to germinate; however, irradiances of 25 and 100 mu mol photons M-2 S-1 were equally sufficient for germination. Rafts of seeded nets were deployed in Cobscook Bay, Maine, at two distances from salmon aquaculture pens and at a control site on a nearby, fallow aquaculture site (no salmon). There was no difference in nitrogen content of harvested thalli; however, both the density and the surface area of harvested thalli were different among the sites. The possible causes of these differences are discussed in the context of potential use of Pumbilicalis in IMTA.
Pages
Marine Agronomy Group, CAFNRM, UH-Hilo
200 W. Kawili st., HI 96720, USA
Contact: Marine.Agronomy.Group@gmail.com
Funding for this web portal is provided by the World Wildlife Fund and the University of Hawaii-Hilo.