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Reference breadYeast breads were developed from rice flour (80%) and potato starch (20%). Using sensory measurement from a trained panel, response surface methodology (RSM) was applied to find carboxymethylcellulose (CMC), hydroxypropylmethylcellulose (HPMC), and water level combinations for gluten-free breads from three different rice flours. Formulations resulted in rice breads that met wheat bread reference standards for moistness, cohesiveness, yeasty flavor, adhesiveness, aftertaste, top crust and crumb color, cell size uniformity and predominant cell size. Medium grain rice flour breads met more sensory reference standards than long grain rice flour breads.A commercially prepared wheat flour (white) bread served as reference (REF) for all sensory evaluations. Eighteen loaves of bread were purchased (within 4 hr of baking) in five different lots over six wk. Reference breads were frozen after purchase for l-5 days and thawed (21"C) for 1.5-2 hr before sampling for sensory evaluation. Sensory evaluationNineteen potential panelists were screened using a series of 16 triangle tests in which panelists chose the odd rice bread sample with respect to firmness and/or moistness. Sixteen panelists were subsequently selected, on the basis of ability to correctly identify the odd sample (70% of the time) and on their availability, and trained 11 weeks. During training, panelists individually evaluated a variety of rice and wheat flour yeast bread samples. Group discussions facilitated development and refinement of the vocabulary for sensory characteristics of the rice breads, the ballot, appropriate descriptors and procedure for assessing rice bread quality. Fifteen attributes (yeasty odor, rice odor, firmness, moistness, cohesiveness, yeasty flavor, rice flavor, adhesiveness, graininess, aftertaste, top crust color, crumb color, predominant cell size, cell size uniformity and cell wall thickness) were selected for assessment of rice breads. Two performance evaluations were conducted, after the sixth and tenth week of training, according to the procedure of Cross et al. (1978). The panel was selected, based on results of the second evaluation. The panel consisted of 8 female students and staff in the Faculty of Home Economics at the Univ. of Alberta who were regular yeast bread consumers. INTRODUCTIONSPECIAL DIET PRODUCTS, such as gluten-free breads, often do not provide the sensory quality consumers expect (Paulus, 1986). To ensure gluten-free bread is accepted, gluten-free yeast breads with sensory characteristics similar to those of wheat flour yeast bread are needed. However, developmental research on gluten-free breads rarely has included sensory evaluation by a trained taste panel. Response surface methodology (RSM) has been successfully used with trained taste panel evaluations in development of baked products such as pie crusts (Smith and Rose, 1963), high protein bread (Henselman et al., 1974) and cakes (Vaisey-Genser et al., 1987). This suggested that use of both RSM and trained panel sensory evaluation wo...

A gluten-free wheat bread replacement was developed from rice flour (80%) and potato starch (20%). Using objective measurements as responses, response surface methodology was utilized to find carboxymethylcellulose (CMC)-hydroxypropylmethylcellulose (HPMC)-water combinations which could successfully replace gluten in the rice flour yeast breads from each of three rice flours. CMC and water had the greatest effect on the responses measured; HPMC had the least. Rice bread formulations were found that resulted in breads which met wheat (white) bread reference standards for specificvolume, crumb and crust color, In&on firmness and % moisture.

The effect of various levels of ascorbyl palmitate (AP) and of butylated hydroxyanisole/toluene (BHA/BHT) on the accelerated storage stability of canola oils was determined by sensory, gas liquid chromatographic (GLC) and chemical evaluations. In Schaal oven tests (6X, O-16 days), chemical, GLC and trained sensory panel data indicated that 200 ppm AP retarded autoxidation in stored canola oils.Monoglyceride citrate (MGC) addition to oils containing 200 ppm AP did not enhance oil stability. Fluorescent light tests (7500 lux, 24"C, O-24 hr) showed that 200 ppm AP, with or without MGC, had a limited effect in protecting canola oil from photooxidation. BHA/ BHT, at 100 ppm each, with MGC, did not improve canola oil stability.