Effects of additives on the rheological and mechanical properties of non-conventional fresh handmade tagliatelle

The effects of the following additives on the amaranth (A), quinoa (Q) and oat (O) dough rheological properties and the extruded tagliatelle dough mechanical characteristics were evaluated: carboxymethylcellulose of sodium (CMC), whey protein isolate (WPI), casein (CAS), chitosan (CHIT) and pregelatinized starch (PS). The amaranth, quinoa and oat rheological dough properties and amaranth, quinoa and oat tagliatelle mechanical characteristics were compared to those of their respective controls (ACTRL, QCTRL and OCTRL) and of the SEMOLINA sample. The storage modulus (G′) and loss modulus (G″) values of the quinoa and oat doughs with PS were similar to those of the semolina dough. For all tagliatelle samples, WPI reduced the elastic modulus or Young's modulus towards that of the semolina tagliatelle. Moreover, the additives did not have particular influence on the tenacity with the exception of the amaranth tagliatelle added with WPI.     

Study of the effect of hydrothermal process conditions on pasta quality

The effect of hydrothermal treatment on the pasting, hydration properties and colour quality of commercial fresh pasta were studied following an Instantaneous Controlled Pressure Drop treatment. This hydrothermal procedure involves a physical modification at high temperature (<144 °C) and restricted moisture content (<30%) during a very short time (15–40 s) followed by a rapid pressure drop to a vacuum (50 mbar). Two process variables (steam pressure level and processing time) were investigated using response surface methodology. Steam pressure level had the greatest effect on hydration and pasting parameters. Increased pressure resulted in elevation of mass ratio between cooked and uncooked pasta (W_i/W₀)_{100 °C} and reduction of for all treated pasta. The optimum cooking time of untreated pasta was 7 min (W/W₀=2.4), whereas for the same ratio it was less than 1 min for pasta treated at pressures ranging between 2.5 and 3.5 bar. The viscosity at 10 min (V₁₀) increased linearly when the pressure level increased. V₁₀ was 146 cP for untreated pasta whereas it reached 2659 cP for pasta treated at 3.9 bar (144 °C) for 25 s. The cold paste viscosity and setback viscosity decreased when the pressure varied from 1 to 3.9 bar.     

Effects of ultrasonic treatment on the cooking and fermentation properties of Shanlan rice

Shanlan rice is an endemic upland rice in Hainan province, China. In this study, we investigated the effects of ultrasonic treatment (UT) on the cooking and fermentation properties of Shanlan rice. These effects were evaluated by multiple physical and chemical indicators via scanning electron microscopy (SEM), low-field nuclear magnetic resonance (LF-NMR), and high-performance liquid chromatography (HPLC). According to the minimal cooking time and the content of total leached solids, the optimal ultrasonic power and time were determined to be 240 W and 30 min, respectively. The results indicated that the ultrasonic treatment broke the rice surface, loosened the inner structure of rice, and extended the relaxation time. These changes increased water absorption during the cooking process by 8.2% and promoted saccharification and alcohol production at the initial fermentation stage, with a 54.1% higher alcohol content on the first day. The rice wine brewed from the treated rice showed differences in the non-volatile acid contents; malic acid and tartaric acid contents increased, while the acetic acid content decreased significantly. Moreover, the red colour and brightness of the rice wine were significantly improved after the ultrasonic treatment, with a 16.6% increase in the rice wine yield.     

Effect of hydrothermal treatment of rice flour on various rice noodles quality

The rice noodle industry in Thailand is facing problems regarding rice flour quality. This research aims to study the effects of hydrothermally modified rice flour on improving rice noodle quality. High-amylose rice flour (Chai Nat 1 variety) was modified using heat–moisture treatment (HMT) and annealing (ANN). Response surface methodology (RSM) with face-centered central composite design (FCCD) was applied to optimize the hydrothermal treatment condition. The effects of treatment conditions – moisture content; heating temperature and heating time on pasting; rheology; and textural properties of rice flour gel – were observed. A contour plot showed that all responses using HMT increased when moisture content and heating temperature increased. But heating time had no significant effect on response variables. ANN showed a lower response than HMT for all parameters. The optimum modified conditions were then matched with those of commercial flour for fresh, semi-dry and dry rice noodles; this showed no significant differences in texture or cooking quality (P≤0.05). The storage modulus (G′) after cooling of HMT (19,100 Pa) was much higher than that of ANN (5490 Pa). The differences in rheological properties of both treatments supported their proper uses to achieve various rice noodle qualities.     

Effects of wheat cultivar,cooking method,and bulgur type on nutritional quality characteristics of bulgur

The aim of this study was to investigate the effects of different wheat cultivars, cooking methods, and bulgur types on nutritional quality of bulgur. Cultivars, cooking methods, and bulgur types had significant effects on phytic acid, total phosphorus, soluble, insoluble, and total dietary fibre contents of bulgur. Besides, cultivars and cooking methods were found to have significant effects on yellow pigment, thiamine, and riboflavin contents of bulgur. The results indicated that the variation among genotypes was wide on all parameters investigated. Bulgur cooked using the steam cooker cooking method had better nutritional properties. Regardless of the cooking method, fine bulgur type had higher nutritional values. However, it was observed that there were losses in nutritional values (ranging from 17.5% to 55.7%) during bulgur production from wheat. The losses resulted particularly from cooking and debranning steps during bulgur production. It can be concluded that the steam cooker cooking method showed promising results in terms of the nutritional quality of the bulgur.