Influence of the Fertilization on the Properties of Durum Wheat Grain and Pasta Products
G. PANAYOTOVA1 and St. GORBANOV2
1 Cotton and Durum Wheat Institute, BG – 6200 Chirpan, Bulgaria
2 Agricultural University, BG – 4000 Plovdiv, Bulgaria
PANAYOTOVA, G. and St. GORBANOV, 1999. Influence of the fertilization on the properties of durum wheat grain and pasta products. Bulg. J. Agric. Sci., 5: 425-430
A long term experiment since 1967 in The Cotton and Durum Wheat Institute, Chirpan, was used to study the effect of the fertilizers on the grain quality of the durum wheat variety Zagorka. Nitrogen and phosphorus fertilizers in rates 0, 60, 120 and 180 kg.ha-1 and potassium in rates 0, 60 and 120 kg.ha-1 were applied.
Seed samples during the period 1988-1995 was analysed. It was determined the weight of 1000 grains,test weight, total glassiness, crude protein, wet and dry gluten, semolina output, carotinoids content. Macaroni (a hollow long tubes of 5 mm diameter), produced of seed samples with different fertilization was analysed. It was found the strength by Lukjanov's method, the cooking loss (%) and coefficient of volume increase.
It was found that the glassiness is effected by the nitrogen nutrition and increases with 33.9-44.1 %. The 1000 grains weight varies from 28.4 to 51.2 g depending on the weather conditions and fertilization and decreases with 5.07 % at higher nitrogen rates. The test weight is not influences significantly by nitrogen application.
The nitrogen may increases the crude protein, wet and dry gluten and carotinoides.The protein goes up to 28.20 %, wet gluten – to 43.16%, dry gluten – with 29.10 to 43.64 % , carotinoid pigments – to 15.7 % over the check.
The grain yield is in high positive relationship with glassiness, protein and gluten content. Between nitrogen fertilization and the weight of 1000 grains there is high, but no proved negative correlation (r = -0.930).
Nitrogen application increases the strength of macaroni with 25.7 % at higher rates, dry matter loss in boiled water decreases and at N180 is 4.04 times less, the elasticity and the form is keep at boiling.
Key words: durum wheat, fertilization, grain, quality, macaroni