Nitrogen content, dietary fiber, and digestibility in algal food products

Abstract

The basic nutritional aspects and parameters of freshwater and marine algal food products are described. Blue-green algae (<I>Spirulina pacifica, S. platensis</I>), green algae (<I>Chlorella pyrenoidosa</I>), red algae (<I>Palmaria palmata, Porphyra tenera</I>), and brown algae (<I>Eisenia bicyclis, Hizikia fusiformis, Laminaria japonica, Undaria pinnatifida</I>) were used for this purpose. The ash content, total nitrogen, dietary fibers, and in vitro digestibility of the above-mentioned algal species were studied. The ash contents amounted to 8–11% (for freshwater) and 9–33% (for marine) of the weights of the algal samples. The total nitrogen contents were analysed using a modified Winkler’s method; in the process, higher nitrogen contents were observed in freshwater algae than in marine ones. For the analysis of dietary fiber contents, the instrument Ankom<sup>220</sup> Fibre Analyser was used. The marine brown algae species were generally assigned higher contents of dietary fiber than the freshwater algal products. The results of the dietary fiber analysis differed with the methodologies used. Pepsin, pancreatin, and a combination of both were applied for the study of <I>in vitro</I> digestibility. Generally, brown algae showed the worst digestibility in comparison with other algal food products.

Lactic acid fermentation of Arthrospira platensis (spirulina) biomass for probiotic-based products

“…The easily breakable cell of A. platensis favours the access of the digestive enzymes to the intracellular content, and for this reason, chemical or physical processing steps are in general not required to improve spirulina biomass digestibility (Becker 2007(Becker , 2013. Mišurcovà et al (2010) evaluated the in vitro digestibility of A. platensis and Spirulina Pacifica ® produced by Cyanotech…”

Chemical composition and nutritional properties of freshwater and marine microalgal biomass cultured in photobioreactors

“…Generally, this is accomplished through in vivo and/or in vitro protein digestibility bioassays. In vivo protein digestibility data of microalgae fed to farmed animals and fish is scarce and inconclusive with reported values typically determined with rats which are highly variable (11-87 %) in the literature (Mišurcova et al 2010). A limited number of reports using varying in vitro methods have shown a wide range of IVPD (27-97 %) for a small selection of microalgae species.…”

“…A limited number of reports using varying in vitro methods have shown a wide range of IVPD (27-97 %) for a small selection of microalgae species. Reported IVPD for Chlorella are 55-66 % (Tamiya 1962), 27-93 % (Hedenskog et al 1969), 44-57 % (Janczyk et al 2005), 70-97 % (Morris et al 2008), and 61-79 % (Mišurcova et al 2010). IVPD for Spirulina has been reported to be 84 % (Lipinsky and Litchfield 1974)and 70-85 % (Devi et al 1981), and work with other species (Nostoc, Scenedesmus,a n dMicrocystis)h a v es h o w nI V P D values of 29-93 % (Hedenskog et al 1969;de la Fuente et al 1977;Horietal.1990).…”

Heat treatment increases the protein bioaccessibility in the red seaweed dulse (Palmaria palmata), but not in the brown seaweed winged kelp (Alaria esculenta)

“…In general, brown seaweeds contain approximately half the amount of proteins compared to red seaweeds (Dawczynski et al 2007;Misurcova et al 2010). One well-known exception to this is Undaria pinnatifida (wakame), whose protein content has been shown to be comparable to some of the red seaweeds (Dawczynski et al 2007;Taboada et al 2013).…”