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Cereal Chem. 76(5):638-645Durum wheat gluten strength is important in determining extrusion properties and pasta cooking quality. Durum wheats varying in strength were tested using an alveograph and a 2-g micro-mixograph, both widely accepted techniques for determination of physical dough properties. Doughs from the 2-g micro-mixograph were characterized by dynamic oscillatory and large deformation creep tests using a controlled stress rheometer. Mechanical properties obtained from both testing regimes were strongly correlated with many of the parameters provided by the alveograph and micro-mixograph. Maximum strain attained after 5 min creep ranged from <5% for the strongest least extensible cultivar to >25% for the weakest cultivar, with a coefficient of variation among replicates of <10%. Storage modulus (G′) at 2 Hz ranged from ≈7,000 Pa for the weakest cultivar to >16,000 Pa for the strongest, least extensible cultivars, with a coefficient of variation of <6%. Tan δ (G′′/G′) values were ≈0.4 for the strongest versus >0.5 for the weakest cultivars, indicating the larger contribution of the elastic component in the strong cultivars. The rheometer allows discrimination of durum wheat cultivars of varying gluten strength while requiring less sample than traditional physical dough testing techniques.

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Laird No. 1 lentils micronized (high-intensity infrared heat) to give internal temperatures of 138 and 170 °C were compared to unprocessed lentils stored at room temperature. Micronized lentils, which had been tempered to 33% moisture for 16 h, required less force to compress after cooking and contained increased levels of gelatinized starch and pectic substances but decreased levels of soluble protein, phytic acid, and neutral detergent fiber compared to the unprocessed lentils. Cell walls in the micronized lentil were less susceptible to fracture, and the microstructure was more open. Properties of the micronized lentils were better when the internal temperature reached 138 °C. When micronized to an internal temperature of 170 °C, cooked lentils were harder, possibly due to greater moisture losses and a change in the neutral detergent fiber. Micronization resulted in a slight darkening of the lentils, and this was accentuated at 170 °C.

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