Rheology of Muffin Batters by Line Spread Test and Viscosity Measurements
This work was aimed to quantify the flow properties of muffin batters by Line Spread Test (LST) and to establish a valid correlation between their line spread distance and viscosity. LST is a quick and inexpensive method for comparing relative viscosities of food slurries or a solid-liquid suspension type of food materials, like muffin batters. The rheological proper ties of muffin batters formulated using gluten free flours were studied. Five different combinations of rice flour and quinoa flour were studied as gluten free flour combinations. Control muffin batters were formulated using 100% wheat flour, which is a gluten positive flour. Density, pH, line spread distance and viscosity were measured for all six batter formulations including control. All tests were performed in triplicate and all data were analyzed statistically. In general, gluten free flour reduced the density and increased the acidity of muffin batters. Whereas, line spread distance was increased and viscosity was decreased with replacement of quinoa flour to rice flour in the muffin batters. A valid correlation between line spread distance and viscosity was observed. The inverse of LST in cm/sec was observed to be close to the viscosity in poise for muffin batters in this study.
Development of an objective method for assessing viscosity of formulated foods and beverages for the dysphagic diet.
OBJECTIVE
To develop and validate a practical, economical, and objective viscosity assessment tool, the line-spread test, for foods and beverages formulated for the dysphagic diet. The line-spread test is based on the measure of product dispersion over a flat surface.


DESIGN
Viscosity-altering formulations for a selection of soups and beverages commonly served to patients with dysphagia at a local hospital were developed under controlled conditions. The samples were presented to a trained sensory panel for evaluation by quantitative descriptive analysis and were measured by the line-spread test. Numeric results of the two tests were compared.


SETTING
The Food Research Laboratory with private sensory booths at Mount Saint Vincent University.


MAIN OUTCOME MEASURES
Results of the sensory evaluation and the line-spread test would strongly correlate, indicating predictive validity, but the line-spread test would be more reliable and show variability in measurement.


STATISTICAL ANALYSES PERFORMED
Correlation, analysis of variance (ANOVA), and standard deviations (calculated from the within-group mean square error of the ANOVAs).


RESULTS
ANOVA showed that both the sensory panel results and the line-spread test values indicated significant differences among the samples. Standard deviations indicated less variability in line-spread values. There was a strong positive correlation (r = .90 to .97) between the two types of results, which indicated strong predictive validity for the line-spread test.


APPLICATIONS
The line-spread test is a reliable and valid tool to assess viscosity of formulated foods and beverages for the dysphagic diet and can be readily and economically adapted to any dietary department for product development and quality control.
Effect of Soybean Cyst Nematode (Heterodera glycines) on Yield of Resistant and Susceptible Soybean Cultivars Grown in Ohio.
Soybean (Glycine max) producers in Ohio rarely use soybean cyst nematode (Heterodera glycines, SCN)-resistant cultivars because of concerns over limited yield potential and lack of resistance to Phytophthora sojae. A two-year study was initiated to determine grain yield and nematode population increase on soybean cyst nematode-resistant cultivars in maturity groups II and III in production fields. Sites differed in soil texture, nematode densities, and P. sojae infestation at a number of locations in Ohio. Soil was assayed for nematode densities before planting and at harvest. Yields of resistant cultivars averaged 0% to 18% higher than those of susceptible cultivars in fine-textured soils with average preplant populations ranging from 463 to 14,330 SCN eggs/100 cm(3) soil. In coarse-textured soils, yields of susceptible cultivars were 21% to 56% less than the resistant cultivars with average preplant densities ranging from 1,661 to 15,558 SCN eggs/100 cm(3) soil. The reproductive index ranged from 0.1 to 5.5 for resistant cultivars and 0.4 to 112 for susceptible cultivars. In 1993, yield of P. sojae-susceptible, nematode-resistant 'Asgrow A 3431' was as high as yield of the P. sojae-resistant, nematode-susceptible cultivar 'Resnik' in a Phytophthora-infested field. The nematode-resistant cultivars Madison Experimental 131527 and Asgrow A3431 had higher yields than AgVenture AV1341 and susceptible cultivars Resnik and Kenwood when compared over five nematode-infested sites. Nematode-resistant cultivars were found to be excellent alternatives to currently grown susceptible cultivars for managing SCN where group III cultivars are used. However, better cultivar alternatives may be needed for sites with combined Phytophthora root rot and cyst nematode problems.