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The positive effects of drying pasta in high temperatures
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by Luciano Mondardini, R&D Director, Pavan, Italy
he positive effect of high temperatures on the drying of pasta is a fact that can no longer be questioned. Its use has improved the cooking quality and appearance of pasta made from soft wheat. The mechanism, or at least the main mechanism, by which cooking quality has improved in soft wheat pasta is essentially due to the transformation that occurs in the protein chains when they are exposed to temperatures that enable coagulation. It is known that the protein chains of soft wheat gluten in comparison to durum, are longer in length and behave less tenaciously when subjected to stress. This is supposedly due to a different tendency to be distributed in space and to form hydrogen bridges or in smaller quantity or with less potential. This generates a weaker glutinous network, less able to keep the starch wrapped when it, due to the effect of cooking in water pasta, swells and gelatinises. The high temperature treatment, made in a phase where the protein chains still have enough water to be in their maximum development of hydrogen bonds, blocks this network with coagulation allowing it to make the most of its binding capacity. In addition, it has been observed that in soft wheat the quality of pasta made with high-temperature technology relates more closely to total protein content than gluten content. It is as if the albums and globulins that do not form part of the glutinic complex, submitted to the rapid coagulation process in the initial drying phases, could make a significant contribution to the glutinic complex in the formation of a containment net.
52 | February 2018 - Milling and Grain
Tests conducted at the Italian Cereal Institute
Here is an example of a report, drawn from the tests conducted at the Italian Cereal Institute in Rome for a quality provision of spaghetti pasta: OJ= Overall Judgement values between 20 (very bad quality) and 100 (excellent quality) TOM= Total Organic Material Organic material that is lost on the surface of a spaghetti, values from 1.4 (very good) to above 2.8 (very bad). As we can see, the correlation found in the high temperature dryness is only related to the percent of proteins and not to gluten quality.
Low temperature OJ =
13.29 + 2.42 * % protein + 1.57 * gluten quality manual method OJ = 24.61 + 1.94 * % protein content + 0.03 * W (Chopin alveograph W value) TOM = 2.94 - 0.055 * % protein content - 0.058 * gluten quality manual method TOM = 2.51 - 0.031 * % protein - 0.001 * W (W value of the Chopin alveograph)
High temperature
OJ = 40.50 + 2.04 * % protein content TOM = 2.08 - 0.065 * % protein content * re-elaborated from: - D’Egidio M.G., Mariani B.M., Novaro P. 1993. Influence of raw material characteristics and drying technologies on pasta cooking quality: a review of our results. Italian Food & Beverage Technology. 1, 29-32. - D’Egidio M.G. 1997. Influenza della materia prima sulla qualità della pasta. Molini d’Italia. 12, 15-18.