Background and objectives One hard wheat and one semi‐hard wheat were milled on commercial, laboratory, and household‐scale flour mills with rotating elements ranging from 0.1 to 1.0 m in diameter and speeds ranging from 65 to 40,000 rpm. The aim of the study was to assess and compare the quality of the flour from each of mills. Findings Pasting viscosities, Farinograph development time and stability, and loaf volumes (LVOL) were all markedly influenced by whole‐wheat flour particle size, which differed markedly between mills. LVOLs were acceptable using the flours produced by all the mills. Best flour quality came from the three mills that produced the finest whole‐wheat flour. Of these, the superior flour came from the 1.0‐m‐diameter Osttiroler stone mill. This mill produced whole‐wheat flours with more optimal levels of starch damage and higher water absorption than did the smaller mills. There was no evidence of degradation of gluten functionality even at a flour temperature of 51°C. Conclusions The mill used affected almost all flour quality traits. However, the characteristics of the wheat applied to the mill were the dominant influence on flour functionality. Starch damage may better indicate milling severity than the heat generated during the milling process. Significance and novelty This is the only study, that we know of, on the comparative performance of household‐scale flour mills. The study also presents an alternative way of visualizing particle size distributions of flours.

Falling number (FN) values below 300 sec in the apparent absence of preharvest sprouting are periodically observed in the U.S. Pacific Northwest (USPNW). Wheat in the USPNW is predominantly soft‐grained and often grown under conditions conducive to low grain protein concentration (GPC). Our hypothesis is that low GPC per se could be responsible for some low FN results and not elevated α‐amylase from either sprouting or late‐maturity amylase. The relationship between FN and GPC was investigated using grain from the 2011 wheat harvest. Soft white winter wheat samples from six locations in Oregon were tested in duplicate. Across the entire sample set, FN and GPC were positively correlated (r = 0.65, P ≤ 0.001). When putatively sprouted samples (FN < 280 sec) were removed from the analysis, the correlation was still apparent (r = 0.69, P ≤ 0.001). Hardness index was also correlated with FN (r = 0.45, P ≤ 0.001). Our preliminary conclusion is that GPC can be a substantial modulator of FN in the putative absence of elevated amylase in soft white winter wheat grown in the USPNW.

Barley (Hordeum vulgare L.) has been cultivated for human consumption for millennia. However, most North Americans do not regularly consume barley as a foodstuff. In the last decade, there has been renewed interest in barley production for human consumption. A number of quality traits are used to estimate nutritional value and are useful for food processing. These include β‐glucan, grain protein, kernel hardness, solvent retention capacity (SRC), and hull type. The Pacific Northwest (PNW) of the US is a high‐yielding region that has a reputation for setting dietary and nutritional trends. However, there are currently no winter food barleys adapted to this area. To determine the potential suitability of winter growth habits for food barley production in the PNW, we developed and tested 14 advanced lines. The germplasm was developed via marker‐assisted and phenotypic selection and included hulled lines with waxy starch and hull‐less lines with normal starch. Agronomic and food quality traits were measured on samples from three representative environments (dryland, irrigated, and high rainfall) over a 2‐yr period allowing for assessment of performance within and across locations, as well as genotype × environment interaction. Lines with waxy starch had significantly higher levels of β‐glucan, harder kernels, and higher water retention capacity. Hull‐less lines had, on average, slightly lower yields than hulled lines, with an average difference of 105 kg ha−1. Our future food barley variety development will focus exclusively on hull‐less types because of the simplified processing and consumer interest in the nutritional benefits of whole grain.

Cereal Chem. 91(4):374-377The Rapid Visco Analyzer (RVA) was investigated as a tool to measure oxidative gelation capacity (OGC) of aqueous wheat flour suspensions. One club wheat patent flour was used to determine optimal hydration time, and 33 straight-grade flours (representing 12 hard and 21 soft varieties) were used to observe varietal differences in OGC. A 33.3% w/w flour-water suspension was tested in the RVA at 30°C and 160 rpm for 1 min to establish the flour-water baseline viscosity, and then 65 μL of 3% H 2 O 2 was added and the viscosity of the suspension measured at 160 rpm for a further 5 min. Flour from the club wheat showed that 20 min of prehydration was needed to observe full OGC potential. For the 33 straight-grade flours, final RVA water baseline viscosity was correlated with Bostwick Consistometer (BC) flow (r = -0.93, P ≤ 0.01), and RVA H 2 O 2 peak viscosity was correlated with H 2 O 2 BC flow (r = -0.81, P ≤ 0.01). The RVA was able to differentiate H 2 O 2 -reactive from nonreactive flours. The RVA can observe phenomena not observable with the BC method (e.g., viscosity reduction over time at constant shear rate), which can provide potentially valuable additional information about the nature of OGC in wheat flour suspensions.* The e-Xtra logo stands for "electronic extra" and indicates that Figure 1 appears in color online.

A system to measure optical rotation (OR) and transmitted light (TL) was built and tested by the Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada (CICATA, México). A similar system was built and tested by the Food Process Engineering Group (FPEG) at Oregon State University. OR and TL values, as a function of time and sample temperature, were recorded by a data acquisition system. Sucrose (1% w/v) and distilled water were used to calibrate both instruments while sucrose solutions were used to determine sensitivity, linearity and stability. The OR of sucrose solutions was measured with less than 3% (0.03 to 20 g/100 mL) and 2% error (0.01 to 20 g/100 mL) for the FPEG and CICATA system, respectively. The instrument setup was tested at CICATA by monitoring sucrose hydrolysis and by comparing initial and final OR with published reference values. Application examples tested by FPEG were the characterization of hard candies and the fermentation monitoring of tepache, a prehispanic alcoholic beverage consumed in Mexico and some Latin American countries. These tests confirmed the instrument versatility and the advantages of building modular units with light sources and electronic components available today at low cost. This work showed, using specific applications, that modular units for well-established optical measurements such as OR and TL could have additional applications in food process control and engineering research.Additional key words: in-line/real-time control, sugar inversion, tepache fermentation. ResumenAplicaciones de las mediciones de rotación óptica en el control de procesos y la investigación en ingeniería para el caso de los alimentos Dos centros de investigación, el Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada (CICATA, México) y el Food Process Engineering Group (FPEG) de la Oregon State University, construyeron y evaluaron unidades similares de un sistema de medición de rotación óptica (OR, por sus siglas en inglés) y luz transmitida (TL, por sus siglas en inglés). Se utilizó un sistema de adquisición de datos para almacenar valores de OR y TL en función del tiempo y la temperatura de la muestra. Para calibrar ambos instrumentos, se utilizó una solución de sacarosa (1% p/v) y agua destilada, mientras que la sensibilidad, linealidad y estabilidad se determinaron utilizando soluciones de sacarosa. Las OR de las soluciones de sacarosa se pudieron medir con menos del 3% (0,03 a 20 g/100 mL) y 2% de error (0,01 a 20 g/100 mL) en los sistemas FPEG y CICATA, respectivamente. El sistema CICATA fue evaluado monitoreando la hidrólisis de azúcar y comparando el valor inicial y final de OR con valores de referencia. Para evaluar el instrumento del FPEG, se realizó la caracterización óptica de dulces comerciales y el seguimiento de la fermentación para la producción de tepache, una bebida alcohólica prehispánica consumida en México y otros países de Amé-rica Latina. Estos estudios confirmaron la versatilidad del instrumento y las ventajas de una construcción modular ...