In present paper we have examined the effect of mineral fertilization on the extensograph characteristics of wheat-flours. The baking quality of winter wheat is largely determined by cultivar, but it can be influenced by fertilization. Flours were from 4 cultivars grown at six nitrogen fertilizer. The average flour protein content of cultivars...was very different (11.8, 13.0, 14.3, and 13.07%, respectively). We have found that the extensograph
properties of dough are affected by mineral fertilization, nevertheless, different cultivars distinctly react to the increase of fertilizer doses. We estimates the correlation between flour protein content and extensograph properties, based on our investigations, it became obvious that the correlation between flour protein content and extensograph parameters is really strong.
The extensograph is widely used in quality control and research laboratories studying wheat flour quality. The most commonly used measurements include Rm, the maximum resistance (maximum height of the curve); R5 the resistance at a constant extension of 5 cm; E, extensibility (total curve length); Rm/E, the ratio of maximum resistance to extens...ion; and A, the area under curve. The extensograph has proved useful in the classification and assessment of flours on the physical dough properties. Another important application is its use in wheat breeding programs. Furthermore, extensograph is an excellent tool to study the effects of a wide range of ingredients on dough properties of wheat flour (like oxidants, enzymes, salt and additives), and it can also be used measure the changes during the frozen storage. In the present study we provide a review of the scientific literature concerning the possible applications of the extensograph.
Literature experience was utilised to develop a method for the extensograph analog testing of paste with a QTS25 Texture Analyser. 54 wheat flour samples from the same variety from variety-preservation experiments at the Szeged were tested with this method. A study was made to establish whether the method is suitable for the estimation of resul...ts derived by traditional classification (trial baking, farinograph and gluten tests).
A close and significant correlation was found between the hardness and area data measured with a QTS25 micro-extensograph, the farinograph values and the gluten spreading data, and also between the stretching index (BC/AC) and the water uptake capacity. These correlations correspond well with the findings from a previous experimental series on industrial flour samples. A close and significant correlation was likewise observed between the grain hardness established by the MININFRA method and all the QTS25 micro-extensograph data. In contrast with earlier QTS25 data, however a close correlation was not found between the QTS25 data and the loaf characteristics.
With the use of micro-extensograph data, the estimation of the baking industry value has been improved through stepwise variable selection, with the inclusion of several variables. The estimation of loaf volume could also be solved by means of stepwise variable selection with the inclusion of QTS25 and MININFRA data.
Triticale is likely used in many countries in human consumption, due to its advantageous agronomical and nutritional properties mostly in blends. The baking quality of blends depends not just on the proportions of the used flours but also on their individual quality what can be influenced by fertilizer treatments.
22 flour blends were p...repared with commercial wheat flour and triticale wholemeal flour in proportions from 0% to 100%. The triticale was treated with different amount of fertilizers (N30P30K30, N60P0K0). Changes of wet gluten contents and extensograph parameters of the blends were determined. The quality of blends significantly depends on the fertilizer treatment of triticale beside the proportions of the flours. When the N60P0K0 treated triticale was used in blends, wet gluten and extensibility values were significantly higher, but in case of resistant to extensions (Rmax) the N30P30K30 treated samples gave higher values. The measured values of wet gluten and extensibility were above the expected values (synergism), while in the case of resistance to extension the expected values were higher than the measured values (antagonism).