Antinutritional compounds

Varga, T.K. and Diosady, L.L. 1994. Simultaneous extraction of oil and antinutritional compounds... 

For maximizing protein yield and minimizing contaminant nucleic acids, alkali extraction at elevated temperatures is a feasible procedure (63,73). However denaturation of proteins during extraction is a serious problem because it significantly destroys functional properties and limits the food uses of the extracted protein (2, 74). In addition to denaturation, exposure of protein to alkaline treatments may also cause other undesirable effects, i.e. racemization of amino acids, g-elimination and crosslinking or certain amino acids and formation of potentially antinutritive compounds (11,23,75). 

Our group and several others have shown that supplementing a diet that has undergone browning with lost amino acids cannot completely restore its biologic value (15,16,17). This suggests the possible formation of some inhibitory or antinutritional compounds during the Maillard reaction. 

Skills in separation of grain components and their analysis are needed to address these problems. Some examples of naturally occurring antinutritional compounds are phytates (already mentioned), phenols, tannins, and trypsin- and a-amylase inhibitors. Phenols and tannins bind with and precipitate proteins in food systems, thus decreasing digestibility. Minimizahon of these compounds in cereals is an objective. 

Procyanidins have been considered antinutritional compounds because they can interact with proteins, starch, essential amino acids, and carbohydrates and inhibit certain enzymes [121-123]. This binding depends on the degree of polymerization the larger molecules tend to bind more efficiently [7]. However, at the dose present in cocoa no adverse effect has been observed [124, 125]. In addition, the level of flavonoids required to induce mutations and cytotoxicity may not be physiologically achievable through dietary sources however the use of flavonoid supplements could result in... 

Sinapoyl esters are considered antinutritional compounds because they have a bitter and astringent taste, thus contributing to the bitter taste of rapeseed meal. The intensity of the bitter taste is comparable to the intensity of the bitter taste of caffeine. In the refining of rapeseed oil, sinapines form complexes with proteins. They show lower antioxidant activity than the corresponding phenolic acids and do not have antimicrobial effects. Sinapines present in the feed of some breeds of laying hens cause an off-flavour and fish-like odour of yolks. 

Matthaus, B. 1998. Effect of dehuUing on the composition of antinutritive compounds in various cultivars of rapeseed. Fett/Lipid 100 295-301. 

Griffiths, D.W., Birch, A.N.E. and Hillman, J.R. (1998) Antinutritional compounds in the Brassicaceae,. Analysis, biosynthesis, chemistry and dietary effects. /. Hortic. Sci. Biotechnol, 73, 1-18. 

What are cyanogenic glucosides What kind of cereal, and in what stage, contains important quantities of these antinutritional compounds ... 

Condensed tannins are found in all seeds but represent a potential antinutritive compound that may reduce digestibility of rations in ruminants and nonruminants (Matthaus and Angelini, 2005). In CameUna, tannin levels are 1.1 mg/g, which is considerably less than rapeseed (4mg/g) (Matthaus and Angelini, 2005). Others report a range from 1 to 2mg/g, but still less than rape-seed although similar to mustard and crambe (Matthaus and Zubr, 2000). 

Hempseeds, technically achenes, contain 19-38% oil and about 20-38% protein (Kriese et al., 2004 Ivdnyi, 2006 Da Porto et al., 2014 Vonapartis et al., 2015). Other components include about 27-36% fiber and 4-6% minerals (House et al., 2010 Vonapartis et al., 2015) as well as tocopherols, carotenoids, and phenolic compounds (Oomah et al., 2002 Kriese et al., 2004 Chen et al., 2010 Vonapartis et al., 2015). Much of the fiber resides in the seed huU (House et al., 2010). For this reason, shefied/dehulled hemp seeds contain higher levels of oil (28-53%) and protein (20-39%) with lower levels of antinutritional compounds (House et al., 2010 Chen et al., 2010). 

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