Page 53 - New additives and ingredients in the formulation of aquafeeds

replacement of insoluble casein in water to soluble casein, improved survival
and increased growth of common carp larvae, being of great importance the
solubility and the hydrolysis degree of the products compared. Also, Tonheim
et al. (2007) in a study on the nitrogen content and digestibility of foods and
food ingredients in nutrition of larvae of both soluble and insoluble fractions
in water, concluded that the protein bioavailability of dietary sources in fish
larvae depends on a large number of factors such as particle size of food, its
digestibility, rate of digestion and absorption rates.
The amino acid composition of both protein isolates as hydrolysates
obtained in trial plant it is shown in Table 3. As it is shown, the values ​are
very similar between the two products which confirms the goodness of the
hydrolytic process conditions used by using commercial proteolytic enzymes.
In terms of quality, regarding the addition of the essential amino acids as a
nutritional supplement depends entirely on the individual requirements of
each species. Thus, it can be seen that the sulfur amino acids (methionine
and cysteine), tryptophan and lysine may be limiting factors in some cases
when using such products. However, the usual practice will lead to a certain
percentage within a complete feed formulation and considering that the
differences observed respect the nutritional requirements of essential
amino acids are not overly significant, their inclusion in such formulation
would not be a nutritional imbalance in the required protein intake.
There have been described antioxidants peptides that have the ability
to scavenge free radicals and to form complexes with metal ions which
catalyze the reactions of free radicals (Chen et al., 1998). Furthermore, it
has been reported that hydrolysis of proteins from egg yolk with food grade
proteases provides protein hydrolysates with antioxidant activity (Sakanaka
and Tachibana, 2006).
Plant protein isolates and hydrolysates as alternative to the animal protein in aquaculture diets 51
Figure 1. Molecular profile by gel filtration chromatography of chickpea and
lupin hydrolysates and isolates obtained in trial facilities.
Figure 2. Protein solubility curves as a function of pH of the chickpea (left
graph) and lupin (figure right) hydrolysates and isolates obtained in a plant pilot scale.
Figure 2: Protein
solubility curves as a
function of pH of the
chickpea (left graph)
and lupin (figure right)
hydrolysates and
isolates obtained in a
plant pilot scale
Figure 1. Molecular profile by gel filtration chromatography of chickpe and
lupin hydrolysates and isolates obtained in trial facilities.
Figure 2. Protein solubility curves as a function of pH of the chickpea (left
graph) and lupin (figure right) hydrolysates and isolates obtained in a plant pilot scale.
Figure 2. Protein solubility curves as a function of pH of the chickpea (left
graph) and lupin (figure right) hydrolysates and isolates obtained in a plant pilot scale.
Chickpea Lupin