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A controlled fermentation process using straight-grade wheat flour, commercially milled from a grist of Canada Western Red Spring (CWRS) wheat and English wheat, and fresh yeast (Saccharomyces cerevisiae) was found to be effective for developing a naturally derived product (ferment) that could be used for processing bread with the minimum use of dough improvers. The effects of ferment storage, fermentation time, and fermentation temperature on the quality of ferment and bread were evaluated to establish optimal conditions to produce a mature ferment. Trials were conducted on a pilot scale for greater relevance to industrialized bakeries. Ferment was assessed for total titratable acidity (TTA), pH, and viscosity. Breads made with ferment were evaluated for processing parameters, dough properties, and bread quality and compared to a control prepared without ferment. During fermentation, maximum TTA levels in the ferment were achieved at 100 min, then decreased by the end of fermentation, and increased by 24 h of storage at 4 °C. Viscosity was stable during fermentation but decreased by 24 h of storage. Inclusion of ferment resulted in reduced mixing times and improved dough extensibility and crumb softness. Specific loaf volume was not impacted, a slight reduction in crumb brightness and crumb structure was detected. Fermentation for 240 min at 35 °C was determined as optimal with a storage time for 24 h.

A study to determine the protein digestibility‐corrected amino acid score and protein efficiency ratio of nine different cooked Canadian pulse classes was conducted in support of the establishment of protein quality claims in Canada and the United States. Split green and yellow pea, whole green lentil, split red lentil, Kabuli chickpea, navy bean, pinto bean, light red kidney bean, and black bean were investigated. Protein digestibility‐corrected amino acid score (PDCAAS) and the protein efficiency ratio (PER) were determined using the appropriate rodent models. All pulses had high digestibility values, >70%, with PDCAAS values greater than 0.5, thereby qualifying as a quality protein in the United States, but only navy beans qualified as a good source of protein. All pulses except whole green lentils, split red lentils, and split green peas would qualify as sources of protein with protein ratings between 20 and 30.4 in Canada. These findings support the use of pulses as protein sources in the regulatory context of both the United States and Canada.

The need to produce wheat with low asparagine concentration is of great importance as a measure to mitigate acrylamide concentration in wheat-based products. The association of asparagine concentration in Canadian bread wheat with cultivar, growing location, fertilizer and their interaction were investigated. Wheat cultivars (8) were grown in 2 locations under 4 fertilizer treatments in triplicate (which consisted of two nitrogen rates (90 or 120 lbs/acre) with or without 15 lbs sulphur per acre). The asparagine concentration ranged from 168.9 to 1050 µg/g and was significantly affected by cultivar, location, and their interaction but not fertilizer treatment. Location and cultivar were responsible for 80% and 14% of the variation, respectively. Some cultivars were not affected by location and maintained their low asparagine accumulation trait. Thus, breeding strategies should aim to identify cultivars that are low asparagine accumulating and are stable across different growing environments.

Dietary supplementation with milled flaxseed has provided significant health-related benefits to patients with cardiovascular disease (the FlaxPAD Trial). The purpose of this study was to examine which foods that contained flaxseed were best accepted over the one year duration of daily supplementation. Milled flaxseed (30 g) or a placebo (30 g of milled wheat) was incorporated into muffins, bagels, snack bars (all in different flavours), buns, tea biscuits and pasta or distributed in bags to sprinkle into their food of choice. Patients were free to choose each day the type of food product that they would consume. Over the course of one year, bagels were consumed > muffins > bars > sprinkles > biscuits > pasta > buns. The trends and quantities chosen were the same for flax and placebo foods. More flavourful varieties were generally better accepted. In conclusion, functional foods containing milled flaxseed will be ingested by a patient population over extended periods similar to placebo foods.

Quality characteristics of five different Canadian whole and split yellow pea flours produced using four different grinding systems were analyzed. Batches (250 kg) of whole and split pea flours were ground from a 1 tonne lot of whole or split peas, respectively, using hammer milling, stone milling, pin milling, and roller milling. Pea flour analysis included particle size distribution; protein, starch, and fiber contents; pasting properties (rapid visco analyzer); starch damage; water absorption capacity; oil absorption capacity; foaming properties; emulsification properties; and color. Grinding method significantly affected (P < 0.05) the coarse particle distribution of the flours, resulting in several changes in the functional characteristics of the pea flours produced.

In the present study, yellow pea (CDC Amarillo) and faba bean (CDC Snowdrop) seeds were soaked overnight and then germinated in the dark at ambient temperature for 24, 48 and 72 h. During the short-term germination, germination percentages higher than 96.6% were achieved and progressive growth of radicles was observed for both varieties. The soaked and germinated seeds were dried at 55 °C and milled into flours, and their chemical compositions, physicochemical properties and in vitro starch and protein digestibility were systematically examined. Overall, soaking and germination did not noticeably alter the chemical compositions of each flour. The most obvious changes in the physicochemical properties were found in the pasting, emulsifying and foaming properties of the pulse flours. Soaking and 24-h germination greatly enhanced the pasting viscosities of the flours; as the germination proceeded, their viscosities gradually decreased, resulting from the degradation of starch by endogenous amylase(s) during pasting. Germination progressively improved the emulsion activity and stability, foaming capacity and foam stability of both pulse flours. In addition, germination enhanced the in vitro digestibility of starch and protein of the flours; however, the treatment did not improve their in vitro protein digestibility corrected amino acid scores (IV-PDCAAS). Short-term germination of 24–72 h has been demonstrated to be an effective approach to generating pulse flours possessing diverse functional properties and enhanced digestibility of macronutrients.

Pulses are a good source of protein and dietary fiber and are rich in vitamins and minerals. Inclusion of pulses in the diet has been shown to be an effective dietary strategy for reducing risk factors for cardiovascular disease and diabetes. Although cooked pulses are consumed in many regions of the world, factors including their long cooking times, the presence of anti-nutritional compounds, and the flatulence associated with their consumption have limited their use but these factors can be minimized through processing. A number of different processing techniques can be applied to pulses including dehulling, splitting, canning, fermentation, germination, roasting, puffing, extrusion, micronization, flour milling, and fractionation. The diverse composition and functionality of processed pulses, pulse flours and pulse fractions provide valuable ingredients for food manufacturers.

The effect of storage on flour and baking properties of pulse flours was investigated. Commercially milled whole (yellow pea, navy bean, and chickpea) and dehulled/decorticated (yellow pea, red lentil) flours were stored in a warehouse, heated in the winter months. Flours were evaluated at 1, 2, 3, 6, 9, 12, 18, 24 months for water absorption capacity (WAC), colour, pasting properties, and lipoxygenase (LOX) activity. Stored pulse flours were combined with wheat flour (stored at −18 °C) as a 20% pulse/80% wheat flour blend, baked into bread and assessed for quality. Flour and baking properties of the pulse flours were not greatly affected with storage but whole flours showed greater changes than dehulled/decorticated flours. The greatest changes were found for flour colour (decreased L*) and bread crumb colour (increased a*). Bread flavour (increased bitterness/aftertaste/pulse flavour) and appearance (lower acceptability) were affected for most pulse flours with storage. The freshly milled flours had the highest LOX activity which decreased significantly by 1 month of flour storage. WAC was higher in the stored flours except for chickpea flour. Pasting properties, bread volume, and C-Cell properties were not consistently altered with flour storage but crumb firmness increased with storage for some flours.

Background Salad dressings supplemented with pulse flours are novel products. A three-factor face-centered central composite design (CCD) was used to determine the effect of pulse flour concentration (3.5%, 7%, 10.5% w/w), egg yolk concentration (3%, 5%, 7% w/w) and oil concentration (20%, 35%, 50% w/w) on the rheological and color characteristics of salad dressings supplemented with pulse flours. Results The consistency coefficient m, plateau modulus G(N)(0), recoverable strain Q(t) and color values were all affected by the concentrations of pulse flours used. Scanning electron microscopy showed that dressings with lower oil and egg yolk contents had a less densely packed network compared with dressings with higher oil and egg yolk contents. Sensory results were most promising for salad dressings supplemented with the whole green lentil, yellow pea with low flour content, and chickpea with high oil content. Conclusion This study should be useful for designing novel types of salad dressings to meet market requirements as well as helping to increase pulse consumption.

Barley is an ancient cereal grain with high nutritional value and very specific health benefits. It is a good source of protein, insoluble fiber, vitamins, and minerals and an excellent source of the soluble fiber β-glucan. β-Glucan has been shown to reduce cholesterol, a risk factor for heart disease, and Canada, the United States, and the European Union have all approved heart-health claims for barley-containing foods. In addition to its nutritional benefits, barley has a pleasant flavor that makes it a practical choice for formulating a variety of health-promoting food products. Whole grain hulless barley flour can be used to formulate health-promoting baked products, pastas, and direct expanded snack/breakfast cereal products. Partial substitution of wheat flour with whole grain barley flour resulted in the production of high-quality products, although modifications to formulation and processing conditions were needed, including higher water absorption levels and longer mixing times. The level of barl...

Pulse flours and outer pea hull fiber offer nutritional advantages over traditional flours and starches used in extruded products. Pulse flours are high in protein and micronutrients and, depending on whether they are made from whole or split seeds, contain high levels of fiber. The levels of starch present in pulse flours, although lower than those in traditional ingredients such as cornmeal, allow for moderate to good expansion of end products. Flour specifications should be considered when selecting pulse flours because milling method can impact both flour particle size and functionality. Yellow pea flour, which had higher levels of starch, showed greater expansion properties than lentil and chickpea flours. The addition of a coarser fiber fraction (outer pea hull fiber) to yellow pea flour, when blended at inclusion levels of 5 and 10%, resulted in minimal changes to the expansion properties of directly expanded products, while still enhancing fiber levels. Challenges encountered when including pulse ...

With growing interest in formulating more nutritious ready-to-eat foods, the food industry is looking for alternative ingredients that can deliver enhanced nutrition and functionality. Pulses are high in protein, dietary fiber, minerals, and vitamins and low in fat, making them ideal ingredients for use in baked goods. Partial substitution of pulse flours for wheat flour in baked goods is possible, although modifications to the formulation and/or processing conditions may be necessary to achieve desired end-product quality. For products such as tortillas, pita breads, and crackers, studies showed it was possible to incorporate pulse flours at levels between 20 and 30%. Depending on the level of substitution, the total dietary fiber content can be significantly increased, which would allow a fiber claim. Studies that examined the addition of various types of pea fiber fractions showed it is possible to enhance the nutritional profile of bagels without significantly affecting end-product quality. Pulse flou...

A method based on compression through a Kramer shear cell was developed for determining the firmness of cooked pulses. Ten laboratories analyzed twenty-six blind duplicates of thirteen different samples in a collaborative study to evaluate the repeatability and reproducibility of the method. Statistical analysis of the collaborative data indicated that within-laboratory repeatability standard deviation (sr) was in the range of 0.53 to 1.43, and among-laboratory reproducibility standard deviation (sR) varied from 0.74 to 1.94. The within-laboratory relative standard deviation (RSDr) of samples ranged from 2.45 to 7.24%, and the among-laboratory relative standard deviation (RSDR) ranged from 4.23 to 8.80%.

BACKGROUND: To increase pulse consumption, pita bread was fortified with pulse flours milled from green lentils, navy beans and pinto beans, which were ground to produce fine and coarse flours. Pita breads were prepared using composite flours containing pulse flours (25, 50, 75%) and wheat flour or 100% pulse flours and adjusting the amount of water required for mixing based on farinograph water absorption. Pita bread quality was evaluated according to diameter, pocket height, specific loaf volume, texture and crust colour. RESULTS: Blends made from pulse flours with coarse particle size showed higher rates of water absorption. All composite flours and 100% pulse flours produced pitas with pockets, confirming their suitability for this product. Crust colour of pitas was affected less by navy bean flour than by lentil flour. Pita breads made with pinto bean flour were superior in texture. Overall, navy and pinto bean flours appeared more suitable for pita bread. Flours with coarse particle sizes produced pitas with better colour and texture. Sensory parameters of pitas containing 25% coarse pinto or navy bean flour were as good as or better than those from the wheat control. CONCLUSION: Acceptable pita breads can be made using pulse flours, although the substitution level is limited to 25%. Copyright © 2012 Society of Chemical Industry

Red and white wheat comparisons have not always shown consistent flavor differences. The objective was to compare flavor properties of whole wheat pan and pita breads made from white and red Canadian hard spring wheats. Flavor attributes were defined by trained panelists who marked intensities using 15-cm line scales. Pan bread made from BW275 and Kanata had significantly lower wheat and wheaty aftertaste intensity than AC Domain (red) and RL4863. Pita bread from Kanata had significantly higher sweet intensity than RL4858, Snowbird and AC Domain (red). Principal component analysis accounted for 74–75% of the variance in both bread types. Biplots showed that some of the white wheat breads tended to be sweeter with less wheaty and bitter with wheaty, bitter and sour aftertastes. Red wheat breads tended to be less sweet, more wheaty and bitter with wheaty, bitter and sour aftertastes. Higher wheaty flavor intensity was associated with visually darker breads. PRACTICAL APPLICATIONS The study revealed that there were distinct flavor differences in pan bread and pita bread made from red and white wheats. The sweeter and milder flavor observed for some white wheats could be a marketing advantage for these newly developed wheats. In pan and pita bread products targeted to consumers that dislike the often wheaty and bitter taste of whole wheat products made from red wheat, white wheat derived whole wheat products with their milder taste may be more acceptable.

Pulses are rich in nutrients. The existence of anti-nutritional components and the length of time required for preparation have, however, limited their frequency of use compared to recommended intake levels. Anti-nutritional components in pulses can be largely removed by heat treatment. Additionally pre-treatment of pulses with heat and processing of seeds into flour could further enhance their use by decreasing processing and preparation times. In this study, trypsin inhibitor activity, functional properties, and microstructural characteristics of flours prepared from different varieties of lentil, chickpea, and pea as affected by roasting and boiling were evaluated. Both thermal treatments resulted in significant reduction ( p p

Summary The impact of storage conditions on volatile flavour profile of field pea cultivars was evaluated. Seeds were kept at 4 °C, room temperature (approximately 22 °C) and 37 °C for 12 months. Headspace solid-phase microextraction gas chromatography–mass spectrometry was used for extraction and identification of volatile flavour compounds (VFCs). Significant (P

The objectives of this study were to evaluate the effect of cultivar, crop year and processing (dry milling, cooking and dehulling) on volatile flavour compounds of field peas using an optimised headspace-solid phase microextraction gas chromatography–mass spectrometry method. Significant differences in area counts of volatile compounds were observed between the different cultivars as well as in area counts of volatile compounds of each cultivar grown in different crop years. Results showed significant reduction in total area counts (TAC) of volatile compounds after cooking and dehulling the seeds. Major differences between whole seeds, cooked and dehulled seeds were found in aldehydes, alcohols, and ketones. Cooked–dehulled peas had the least TAC (7.83E±05) of the volatile compounds compared to the milled-whole peas (6.36E±06), cooked-whole peas (2.00E±06) and milled–dehulled peas (4.33E±06). The results suggest that volatile flavour compounds of different field peas were affected by the cultivar, crop year as well as processing conditions.

Study objectives were to formulate a nutritious acceptable snack bar partially replacing oats with micronized flaked lentils (MFL), and to identify the sensory attributes that contribute to consumer acceptability. Six MFL snack bar formulations exhibiting a wide range of flavor and textural characteristics were developed from a mixture designed experiment. These bars and two commercial bars were evaluated by a consumer panel ( n = 62) and a descriptive panel ( n = 11). The highest mean acceptability values for one commercial sample (6.5) and three MFL bars (6.0) were not significantly different and corresponded to ‘like slightly’ on the 9-point hedonic scale. External preference mapping determined that sweetness, grainy and lentil flavors, hardness, cohesiveness, cohesiveness of mass and moistness had the greatest influence on consumer acceptability. MFL bars contained more dietary fibre, protein and iron in addition to an approximate sevenfold increase in folate over the all oat counterpart.

The effect of cooking time on the textural properties of red lentils was determined using an Instron universal testing machine equipped with an Ottawa texture cell. A sigmoid-shaped force–deformation curve was observed for all samples. As cooking time increased, texture changes, in terms of undercooked and optimally cooked, were identified by changes in slope and plateau force values of the force–deformation curves. At short cooking times, the samples were undercooked, and slope and plateau force values were high. At prolonged cooking times, slope and plateau force values decreased to a certain point and became independent of cooking time as values leveled off. However, significant textural changes as determined with sensory methods continued. Cooking time affected the location of the inflection point on the force–deformation curve. Deformation at inflection was a parameter that successfully determined textural differences between cooked samples and overcooked samples. Force–deformation curves can describe cooking quality of red lentils. PRACTICAL APPLICATIONS There is little information available on the instrumental methods used to measure the texture of red lentils despite the fact that red lentils account for the majority of world lentil production and trade. Thus, there is a need to demonstrate how the force–deformation curves resulting from the instrumental measurement of red lentil texture are affected by cooking. A detailed interpretation of a force–deformation curve would allow for investigation of the effects of biochemical differences in red lentils because of genotype, agronomic practices and postharvest handling on the cooking quality. This work used an Instron universal testing machine equipped with an Ottawa texture cell to obtain force–deformation curves that were interpreted and used to explain the effects of cooking on the textural properties of red lentils.

Quality characteristics of five pilot-scale milled Canadian hard white spring wheats were compared to a No.1 grade commercial composite Canada Western Red Spring (1CWRS) wheat. One metric ton of samples was milled on the Canadian International Grains Institute pilot Buhler mill (Buhler AG, Uzwil, Switzerland) into straight-grade (SG), 85% and whole wheat flours. At the SG extraction level, the white wheats with their lighter colored seed coats had improved milling yields (up to 2.6%) and lower ash (0.01-0.09%) than the 1CWRS control wheat. Majority of white wheat flours had higher protein contents than the 1CWRS control flours for all flour extractions. Based on dough rheological properties of the flours, three of the white wheats (Kanata, Snowbird and BW 275) were equal to or better than the red 1CWRS control for nearly all farinograph and mixograph parameters at all flour extractions other than farinograph absorption. Two of the white wheat lines (RL 4863 and RL 4858) had excessively weak and overly strong dough properties, respectively. Evaluation of pan bread, bagels and tortillas showed that white wheats generally produced end-products that were comparable or superior to 1CWRS and that their most significantly positive quality compared to 1CWRS was their substantially lighter colored end-products.

Five Canadian oat genotypes were grown at six environments in Manitoba to assess the effects of genotype, environment, and genotype-by-environment interaction on oat starch properties and end-product quality. Genotypic variation was significant for total starch, amylose content, starch swelling volume (SSV), Rapid Visco Analyser (RVA) pasting viscosities, differential scanning calorimetry (DSC) thermal properties, and starch gel texture as well as the quality of flakes and cooked oatmeal made by laboratory-scale methodologies. Environment was the dominant factor contributing to the total variation of starch content, RVA pasting viscosities, SSV, and DSC thermal properties. Most measurements of starch gel and oatmeal texture were not affected by growing environment. Cross-over analysis revealed that changes in the ranking of genotypes across environments occurred for starch RVA hot paste, breakdown and shear thinning viscosities, work of gel compression, flake hydration capacity, and the proportio...

A wide range of flours varying in prote in content, strength and baking quality were used to investigate the relationship between early-generation screening tests at the Cereal Research Centre, advanced generation testing at the Grain Research Laboratory (GRL) and pilot-scale commercial testing at the Canadian International Grains Institute (CIGI) and Warburton Foods Ltd. Correlations among flour protein content, mixograph, farinograph and baking characteristics were performed. Strong correlations were found between protein content, mixograph peak height and mixograph total energy with baking water absorption at advanced, and pilot-scale commercial levels of baking, which gave a good indication of all baking quality parameters. Mixograph characteristics and protein content from early generation tests furnished information that correlated with baking data and with farinograph measurements. Key words: Protein content, mixograph, farinograph, early-generation test, pilot-scale commercial baking

Two experiments were run concurrently to determine the effect of fresh forage consumption on the production and proportions of plasma and milk fat vaccenic acid (VA), conjugated linoleic acid (CLA), and linolenic acid in diary cattle. In experiment 1, the cows consumed 50, 65, and 80% of their feed intake as pasture with the remainder of intake as a barley-based concentrate. The proportion of VA in milk fatty acids increased 12% when pasture intake increased from 50 to 65% of total dry matter intake and VA, CLA, and linolenic acid proportions increased 26, 18, and 27%, respectively, as pasture increased from 65 to 80% of dietary intake. In experiment 2, fresh forage was compared to conserved hay (cut from the same pasture the previous summer) to determine the effect on plasma and milk fat VA, CLA, and linolenic acid. Also, the effect of crushed solin seed (a flax cultivar that is high in linoleic acid) supplementation to the fresh forage diet was determined. Fresh forage compared to conserved hay in the diet, increased the proportion of CLA in the plasma very low density lipoproteins (VLDL) fraction by 71% but had no effect on linolenic acid. Supplementation of the fresh forage diet with a linoleic acid source increased VA and CLA in the plasma VLDL fraction 25 and 58% and slightly decreased the proportion of linolenic acid. Fresh forage, compared to conserved hay, increased milk fat VA and CLA proportions by 22 and 15%. Supplementing the fresh forage diet with linoleic acid from crushed solin seed further increased milk fat VA and CLA proportions 41 and 25%. Solin supplementation in a lactation diet is a superior method to increase CLA levels in milk fat than feeding fresh forage alone.

The relationship between the physicochemical and cooking properties of yellow peas was examined in this study. A positive correlation was found between seed weight and water hydration capacity. The Peleg model, which was modified, could be used to describe the water absorption characteristics of peas and could be used to predict the rate of water absorption in the initial water absorption period. Cooking time could be measured objectively using the Mattson cooker. Cooking time was found to decrease with an increase in water hydration capacity. Hardness of cooked peas, measured using a texture analyser, was negatively correlated with both seed weight and water hydration capacity. Seed coats had a significant effect on water hydration and cooking quality of peas. Peas with relatively thin seed coats exhibited higher water hydration capacity, shorter cooking times and softer texture after cooking. The effects of soaking and cooking on trypsin inhibitor activity (TIA) and oligosaccharide levels in peas were also studied. Cooking was more effective than soaking in reducing TIA levels and oligosaccharides (raffinose, stachyose and verbascose) in peas. Copyright © 2003 Society of Chemical Industry

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. Des lentilles ont ete traitees aux infra-rouges de facon a obtenir une temperature interne de 138 et 170°.Leurs proprietes ont ete comparees a des lentilles non traitees. La microstructure, la texture et la couleur des differents type de lentilles ont ete etudies. Les proprietes des lentilles micronisees a 138° sont meilleures, celles cuites a 170°sont plus dures, et plus sombres et ont perdu plus d'eau.Par rapport aux lentilles non micronisees, le temps de cuisson necessaire pour atteindre une texture molle est plus court.

Sensory and instrumental analyses were used to evaluate the texture of regular (10%), light (5%), low fat (2.5%) and fat free vanilla (0.4%) ice creams. The light, low fat and fat free ice cream were prepared using a modified pea starch as the fat replacement ingredient. Two processing trials with continuous commercial-like process conditions were undertaken. While the sensory attributes of the light sample were comparable to the regular vanilla ice cream, the trained sensory panel rated the low fat and fat free ice creams to have lower viscosity, smoothness and mouth coating properties. Instrumentally determined apparent viscosity data supported the sensory data. There was good correlation between the instrumentally determined firmness values and the sensory results for firmness. The use of modified starch as a partial fat replacer in vanilla ice cream was demonstrated.

The variability in texture for lentils of different size, from different locations and cooked for varying lengths of time was examined in relation to the sample size and the extent to which the sample was compressed during testing. The force to compress the lentils was found to be dependent on all variables examined and also demonstrated significant interactions between these variables. The coefficient of variability was dependent on the size of the lentil, a two-way interaction between sample size and compression and a three-way interaction between location, cooking time and sample size. Regardless of lentil size, location where the lentil was grown and the cooking time used, the variability in the texture readings was lowest when the larger sample size and maximum compression force were used.

Two samples of flaxseed, Linott and a mixture of several varieties, were milled and stored at 23±2°C for 128 d in paper bags with plastic liners. Samples were evaluated at 0, 33, 66, 96, and 128 d for chemical, sensory, and volatile indicators of quality. Neither the mixed variety nor Linott samples showed a significant increase in peroxide values or conjugated double bonds throughout the 128-d storage period. Only the Linott sample showed a significant increase in free fatty acids, which was likely due to the presence of immature seed in the sample. Total volatiles increased with storage in the mixed variety sample but showed minimal change in the Linott sample. Overall, the levels of total volatiles in the milled flaxseed samples were much lower than levels reported in stored vegetable oils containing significantly lower levels of linolenic acid. Dienals, formed during polyunsaturated fatty acid oxidation, and hexanal, a compound used as an indicator of oxidative deterioration, were found at very low levels in both samples and did not reach high levels throughout the 128-d storage period. A trained sensory panel could not detect any differences in the odor properties of fresh or stored milled samples. No differences in flavor could be detected between bread made with 0- and 128-d milled flaxseed. This study showed that milled flaxseed can be stored up to 4 mon at ambient temperatures without noticeable changes in quality. The presence of endogenous antioxidants in the milled flaxseed may account for the stability observed.

The storage stability of potato chips fried in regular (RCO), hydrogenated (HYCO), low-linolenic (LLCO), and high-oleic (HOCO) canola oils was compared. Potato chips were fried in each oil over a 5-d period for a total of 40 h of frying. Chips from frying day 1 and 5 were packaged and stored at 60°C for 0, 1, 2, 4, 8, and 16 d. Lipids were extracted from the stored chips and analyzed for peroxide values, free fatty acids (FFA), conjugated dienoic acids (CDA), and polar components. A trained sensory panel evaluated the stored chips for odors characteristic of oxidation. Chips were also analyzed for volatile components. Potato chips fried in RCO, LLCO and HOCO developed an intense painty odor, whereas chips fried in HYCO developed an intense stale/musty odor by the end of the 16 d of storage. Chips fried in RCO had greater rates of accumulation of peroxides, FFA, CDA, and polar components and developed higher levels of total volatiles over the 16 d of storage than chips fried in the other three oils. Chips fried in HYCO had lower rates of accumulation of peroxides and CDA than chips fried in LLCO and HOCO, and lower rates of FFA accumulation than chips fried in LLCO. Chips fried in HYCO and HOCO had the lowest amounts of total volatiles during storage. The effect of oil degradation products on potato chip storage stability was not shown in this study since only the chips fried in HYCO from frying day 5 exhibited a significantly greater rate of off-odor development than chips from frying day 1, and only the chips fried in LLCO from frying day 5 had a greater rate of accumulation of volatiles than chips from frying day 1.

The composition of volatile components in freshly-milled buckwheat flour produced from seed stored under controlled atmospheres (97% N 2 , 1.5% O 2 and 1.5% CO 2 ) for 1 year was studied using capillary gas chromatography, mass spectrometry, sniffing port analysis, and sensory evaluation. Twenty-five volatiles were identified from over 100 compounds removed from the flour by a novel dynamic headspace technique and separated by capillary gas chromatography. Eighteen odor-active regions were detected but none were characteristic of the typical buckwheat flour aroma. The concentration of the major buckwheat volatiles decreased with storage of the seed under low O 2 and high CO 2 levels. The content of two of the odor-active volatiles, hexyl acetate and 1-hexanol, however, increased up to 4 fold in samples stored under controlled atmosphere for 60 weeks.

For many grain and grain legume crops, a pretreatment step is often employed prior to processing to improve the quality of the final product. The pretreatment may be tempering, where a uniform specified moisture content in the grain is desired, or soaking, where moisture content is high and unevenly distributed. This study evaluated the effect of moisture contents and reagents as potential pretreatments for micronization (infrared heat treatment) of lentils, the objective being to reduce lentil cooking times. The texture of over-, under- and optimally cooked lentils was defined by sensory methods and by peak force values at 40% compression. As cooking time increased, sensory scores for hardness, chewiness and particle size decreased, as did peak force values. The peak force for optimally cooked lentils receiving no pretreatment was the control used to assess the effectiveness of a given pretreatment. The pretreatments studied were soaking of lentils, tempering of lentils to 20 or 40% moisture with water alone, and tempering to 20 or 40% moisture with solutions of various reagents: sodium salts of carbonate, bicarbonate, phosphate, tripolyphosphate and EDTA, and mixtures of citric and ascorbic acids. For tempering pretreatments, cooking time was reduced as moisture increased, but it was only at 40% moisture that added reagents were effective in reducing lentil cooking times. It was postulated that free water must be available in the cotyledon to allow reagents in the tempering water to reduce cooking time beyond that attainable with water alone. Potential reagents for tempering solutions used as successful micronization pretreatments were 2% sodium tripolyphosphate, mixtures of 1% citric and 2% ascorbic acid, and 150 ppm disodium EDTA. © 1998 SCI.

A ten-member trained sensory panel evaluated regular (RCO) and low-linolenic (LLCO) canola oils that had been stored at 60°C to four levels of consumer acceptance identified in a prior study. These levels were 70, 60, 50, and 40% acceptance for RCO and 80, 70, 60, and 50% acceptance LLCO. Painty odor intensity increased as consumer acceptance decreased. This same trend was found for chemical measurements of peroxide values, total volatiles, total carbonyls, unsaturated carbonyls, and dienals. These chemical indices were significantly correlated with each other, suggesting that they can be used to monitor related changes in oil quality with respect to lipid oxidation. Values for 19 individual volatiles at each consumer acceptance level were also reported. The data collected in this study provide chemical and sensory characterization of stored RCO and LLCO at distinct levels of consumer acceptance.

Flavour compounds influence the taste and quality of foods both of which are very important criteria in food selection and consumer acceptance. Pulse legumes such as field peas are increasingly used in foods such as soup mixes, purees, bakery and other processed products (Heng et al., 2004). In some parts of the world, particularly in Western countries, the presence of off-flavours in peas can be an obstacle to their consumption.

Sensory studies on autoxidation of canola oil, stored under several variations of Schaal Oven test conditions, suggest an induction period of 2–4 d at 60–65°C. Similar induction periods have been observed between canola and sunflower oils, whereas a longer induction period has been found for soybean oil. Canola oil seems to be more stable to storage in light than cottonseed and soybean oils but is less stable than sunflower oil. Storage stability of products fried in canola oil is similar to products fried in soybean oil. Storage stability of canola and cottonseed oils that had been used in the frying of potato chips showed that canola oil was more prone to autoxidation during storage at 40°C. The presence of light aggravated the oxidative effects and was similar for both oils. Advances in our knowledge about the shelf life of canola oil would be strengthened by standardization of Schaal Oven testing conditions and by specifying the testing protocol for photooxidation studies. Methods for training of panelists and for handling and evaluating oils and fried foods require definition. Rating scales used in the evaluation of oils need to be evaluated to ensure that reliable and valid measurements are achieved. Further progress is needed in the identification of chemical indicators that can be used to predict sensory quality of oils.

Ninety-two consumers judged the odour acceptability (yes or no) of regular (12·5% 18:3) and low linolenic acid (2·5% 18:3) canola oils which had been stored at 60°C for 21 and 42 days, respectively. For each storage day an average proportion of acceptance (APA) was calculated. Logistic regression analyses of storage days vs. APA yielded valid relationships for both oils. These equations permitted prediction of the number of days of accelerated storage for APA values from 0·4 to 0·8. The storage time to 0·5 APA, the consumer acceptance threshold, was 12·5 days for regular canola oil and 34·3 days for low linolenic acid canola oil, indicating substantially greater stability for the genetically modified caltivar. The frequency and character of free choice negative odour descriptors which were assigned to both oils at 0·5 APA were similar.

A crude commercial canola oil (Westar) and an oil obtained from a genetically reduced linolenic acid cultivar, were laboratory processed under commercial conditions to finished, deodorized oils. Fatty acid analysis indicated that the linolenic acid content of the low linolenic canola oil (LLCO) was 3.1%, compared to 11.5% for Westar. The LLCO exhibited markedly improved stability during accelerated storage at 60°C (Schaal Oven Test) as evident by negligible changes in chemical indices of rancidity. No significant changes were observed in overall odor intensity or odor pleasantness for the LLCO over the 12 d storage period, whereas significant changes were found for the Westar oil. Comparison of volatiles produced by these oils during storage confirmed enhanced storage stability of LLCO.

Profiles of canned tuna volatiles were obtained using a simple and effective isolation system and high resolution gas chromatography. A high correlation between the volatile profile, chemical groups of components identified and sensory panel scores was obtained. Two models based on chemical groups of components were developed to predict decomposition and rancid off-odor. Recovery of over 80% of the volatile components from canned tuna was obtained with a coefficient of variation of 3.2%.

Dietary flaxseed may have significant health-related benefits due to its high content of the omega-3 fatty acid, alpha-linolenic acid (ALA). However, before extensive work can be undertaken in clinical populations to determine its efficacy, basic information on ALA bioavailability from flaxseed and the physiological effects of its ingestion need to be examined.The purpose of this study, therefore, was to determine the bioavailability of ALA when the flaxseed was ingested in the form of whole seed, milled seed or as flaxseed oil.The flaxseed components (30 g of seed or 6 g of ALA in the oil) were baked into muffins for delivery over a 3 month test period in healthy male and female subjects.Flaxseed ingestion over a 1 month period resulted in significant (P = 0.005) increases in plasma ALA levels in the flaxseed oil and the milled flaxseed supplemented groups. The former group had significantly (P = 0.004) higher ALA levels than the milled flaxseed group. The subjects supplemented with whole flaxseed did not achieve a significant (P0.05) increase in plasma ALA levels. An additional two months of flaxseed ingestion did not achieve significantly higher levels of plasma ALA in any of the groups. However, no significant increase was detected in plasma eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA) levels in any of the flax-fed groups. There were no changes in plasma cholesterol or triglycerides or in platelet aggregation at any time point in any of the groups. Subjects in all of the groups exhibited some symptoms of gastro-intestinal discomfort during the early stages of the study but these disappeared in the oil and milled seed groups. However, compliance was a problem in the whole flaxseed group.In summary, ingestion of flax oil and milled flaxseed delivered significant levels of ALA to the plasma whereas whole flaxseed did not. Whole seed and oil preparations induced adverse gastrointestinal effects within 4 weeks and these were severe enough to induce the withdrawal of some subjects from these two groups. No one withdrew from the group that ingested milled flaxseed and, therefore, may represent a good form of flaxseed to avoid serious side-effects and still provide significant increases in ALA to the body.