engleski

Protein content and digestibility of conventionally and organically grown wheat varieties

Possible differences in the content of nutrients between organically and conventionally produced crops are still ambiguous, since observed differences are biologically plausible or can be attributed to differences in crop management or soil quality. That indicates a need for further high-quality research in this field so in the frameworks of such attempts this study, dealing with protein content and quality of organically and conventionally grown wheat, has been conducted. The effect of organic and convectional farming methods (at constant inter row distance and seed rate) on the protein content and digestibility of eight wheat cultivars was studied in two growing seasons. Protein content was determined using the official AOAC (Kjeldahl) method, and protein digestibility was assessed using in vitro digestion with pepsin/pancreatin and determination of the nitrogen content in the indigestible residue using micro-Kjeldahl method. Conventionally grown wheat grain had significantly higher protein content compared to organically grown grain (13.42 g/100g dry matter vs. 11.44 g/100g dry matter). In addition to farming method applied, climate conditions also significantly influenced grain protein content since significant differences were observed between two studied growing seasons. Protein digestibility was not affected by farming method applied nor by growing season ; similar protein digestibility values were obtained for both organically and conventionally grown grains (81.43% and 82.74% respectively) in both observed growing seasons (82.25% in 2008. and 81.92% in 2009.). Further investigations involving more wheat varieties, wider time frames and analysis of complete amino acid composition and availability are needed in order to supplement existing scattered evidence and provide new insights relating this interesting topic.

Protein content; digestibility; conventionally and organically grown wheat

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