D. Dan Ramdath

Phenolic profiles of 20 Canadian lentil cultivars and their contribution to antioxidant activity and inhibitory effects on α-glucosidase and pancreatic lipase.

Phenolic extracts from 20 Canadian lentil cultivars (Lens culinaris) were evaluated for total phenolic contents and composition, antioxidant activities (DPPH, FRAP, ORAC), and inhibitory properties against α-glucosidase and pancreatic lipase. Twenty one phenolic compounds were identified in the present study, with the majority being flavonoids, including kaempeferol glycosides, catechin/epicatechin glucosides and procyanidins. These phenolic compounds not only contributed significantly to the antioxidant activities, but they were also good inhibitors of α-glucosidase and lipase, two enzymes, respectively, associated with glucose and lipid digestion in the human intestine, thus contributing significantly to the control of blood glucose levels and obesity. More interestingly, it was the flavonols, not the flavanols, which showed the inhibitory activities against α-glucosidase and pancreatic lipase. Our result provides supporting information for developing lentil cultivars and functional foods with improved health benefits and suggests a potential role of lentil consumption in managing weight and control of blood glucose.

Fatty acid, carotenoid and tocopherol compositions of 20 Canadian lentil cultivars and synergistic contribution to antioxidant activities

Understanding the profile of lipophilic phytochemicals in lentils is necessary to better understand the health benefits of lentils. The fatty acid, carotenoid and tocopherol compositions and antioxidant activities of the lipophilic extracts of 20 lentil cultivars (10 red and 10 green) were therefore examined. Lentils contained 1.52-2.95% lipids, of which 77.5-81.7% were unsaturated essential fatty acids. Total tocopherols ranged from 37 to 64μg/g DW, predominantly γ-tocopherol (96-98% of the tocopherol content), followed by δ- and α-tocopherol. trans-Lutein was the primary and major carotenoid (64-78%) followed by trans-zeaxanthin (5-13%). Carotenoids and tocopherols showed weak correlation with 2,2-diphenyl-1-picrylhydrazyl (DPPH) activity (r=0.4893 and 0.3259, respectively), but good correlation when combined (r=0.6688), suggesting they may act synergistically. Carotenoids were found to contribute the most to the strong antioxidant activity measured by photochemiluminescence (PCL) assay. Results from this study contribute to the development of lentil cultivars and related functional foods with increased health benefits.

Beyond the Cholesterol-Lowering Effect of Soy Protein: A Review of the Effects of Dietary Soy and Its Constituents on Risk Factors for Cardiovascular Disease

The hypocholesterolemic effect of soy is well-documented and this has led to the regulatory approval of a health claim relating soy protein to a reduced risk of cardiovascular disease (CVD). However, soybeans contain additional components, such as isoflavones, lecithins, saponins and fiber that may improve cardiovascular health through independent mechanisms. This review summarizes the evidence on the cardiovascular benefits of non-protein soy components in relation to known CVD risk factors such as hypertension, hyperglycemia, inflammation, and obesity beyond cholesterol lowering. Overall, the available evidence suggests non-protein soy constituents improve markers of cardiovascular health; however, additional carefully designed studies are required to independently elucidate these effects. Further, work is also needed to clarify the role of isoflavone-metabolizing phenotype and gut microbiota composition on biological effect.

Effect of Domestic Cooking on Carotenoids, Tocopherols, Fatty Acids, Phenolics, and Antioxidant Activities of Lentils (Lens culinaris)

The phytochemicals and antioxidant activity in lipophilic and hydrophilic (extractable and bound) fractions of lentils before and after domestic cooking were investigated. The hydrophilic fractions in lentils contributed much more to the antioxidant activity than the lipophilic fraction. The phenolic content of lentils was mainly composed of extractable compounds. Significant changes (P < 0.05) in carotenoid, tocopherol, total phenolic, and condensed tannin contents of both extractable and bound phenolics fractions, as well as in antioxidant activities, were found in lentils before and after cooking. More specifically, cooking was found to favor the release of carotenoids and tocopherols and flavonols (kaempferol glycosides), but led to losses of flavanols (monomeric and condensed tannin). Whereas reduced flavanols and other phenolic compounds may have negatively affected the antioxidant activity, other components, especially the lipophilic antioxidants, were increased. The present study suggests that incorporation of cooked lentils into the diet will not cause significant loss to the phytochemical antioxidants and thus will retain the potential health benefits.

Whole Soy Flour Incorporated into a Muffin and Consumed at 2 Doses of Soy Protein Does Not Lower LDL Cholesterol in a Randomized, Double-Blind Controlled Trial of Hypercholesterolemic Adults

Background: Soy protein may reduce coronary heart disease (CHD) risk by lowering LDL cholesterol, but few studies have assessed whether whole soy flour displays a similar effect. Objective: The aim of this study was to assess the dose effect of whole soy flour incorporated into muffins on plasma LDL cholesterol in hypercholesterolemic adults. Methods: Adults aged 30–70 y (n = 243) with elevated LDL cholesterol (≥3.0 and ≤5.0 mmol/L) were stratified by LDL cholesterol and randomly assigned to consume 2 soy muffins containing 25 g soy protein [high-dose soy (HDS)], 1 soy and 1 wheat muffin containing 12.5 g soy protein and 12.5 g whey protein [low-dose soy (LDS)], or 2 wheat muffins containing 25 g whey protein (control) daily for 6 wk while consuming a self-selected diet. Fasting blood samples were collected at weeks 0, 3, and 6 for analysis of plasma lipids [total, LDL, and HDL cholesterol and triglycerides (TGs)], glucose, insulin, C-reactive protein (CRP), and isoflavones. Blood pressures also were measured. Dietary intake was assessed at weeks 0 and 4 with the use of 3 d food records. Treatment effects were assessed with the use of intention-to-treat analysis with multiple imputation and LDL cholesterol as the primary outcome. Results: In total, 213 (87.6%) participants completed the trial. Participants were primarily Caucasian (83%) and mostly female (63%), with a mean ± SD body mass index (in kg/m2) of 28.0 ± 4.6 and systolic and diastolic blood pressures of 122 ± 16 and 77 ± 11 mm Hg, respectively. Despite a dose-dependent increase in plasma isoflavones (P < 0.001), neither HDS nor LDS had a significant effect on LDL cholesterol compared with control (mean ± SEM changes: control, −0.04 ± 0.05 mmol/L; HDS, 0.01 ± 0.05 mmol/L; and LDS, −0.04 ± 0.06 mmol/L). There were no significant treatment effects on total or HDL cholesterol, TGs, CRP, homeostatic model assessment of insulin resistance, blood pressure, or the Framingham 10-y CHD risk score. Conclusion: Consuming 12.5 or 25 g protein from defatted soy flour incorporated into muffins does not reduce LDL cholesterol or other CHD risk factors in hypercholesterolemic adults. This trial was registered at clinicaltrials.gov as NCT01547585.

The Role of Pulses in the Dietary Management of Diabetes

Pulses are highly nutritious foods that are included as part of Canadas Food Guide to promote healthful eating, and they have established health benefits that can contribute to the dietary management of diabetes. A review of studies that have examined the effects of pulse consumption on health outcomes, integral to the management of diabetes, provides credible evidence for improvements in glycemic control, reduction of blood lipids and regulation of body weight. Results from acute feeding trials suggest that postprandial blood glucose response is significantly attenuated by a single pulse serving of between three-quarters and 1 cup. At lower doses, pulses attenuate postprandial blood glucose response more than similar amounts of starchy foods. Long-term pulse consumption of 5 cups per week appears to result consistently in improvements in glycemic control. There is high-quality evidence that supports a role for pulse consumption in the reduction of risk for cardiovascular disease; this provides a sound rationale for the regular incorporation of pulses at about two-thirds of a cup daily in the management of hyperlipidemia in persons with type 2 diabetes. Pulse consumption can contribute to improving satiety, reducing food intake and regulating body weight, which can reduce obesity risk and, in turn, improve diabetes management. Collectively, available evidence provides very good support for a role of regular pulse consumption in the prevention and management of diabetes.

Chemical and Physical Characteristics of Proso Millet (Panicum miliaceum)-Based Products

Celiac disease and gluten sensitivities, as well as obesity and overweight-related disorders, have led to the investigation of gluten-free grains and development of new food products. To address this, refined proso millet and refined corn (control), both gluten-free grains, were used to produce four different product types (muffin, couscous, extruded snack, and porridge). The products contained four different grain combinations (100% proso millet, 75% proso millet/25% corn, 25% proso millet/75% corn, and 100% corn). All products were evaluated for their nutritional composition, in vitro starch digestibility, and expected glycemic index (eGI). Products made with refined proso millet had increased protein (7.6–11.3%), lipid (1.2–6.1%), fiber (7.0–8.8%), and phenolic content (323.5–425 μg/g) compared with those incorporating corn flour (2.5–9.0%, 0.8–4.0%, 2.1–4.1%, and 213–315 μg/g, respectively). As the proso millet content increased, the eGI decreased significantly (P < 0.05). Products made from refined p...

Dietary analysis of randomly selected meals from the Child Hunger and Education Program School Nutrition Program in Saskatchewan, Canada, suggests that nutrient target levels are being provided

In Canada, school meals are regarded as important for social, educational, and nutritional reasons and have been provided for several years because of concerns about the health and welfare of children, especially those from low-income households. They are generally offered as local community organization and individual schools, are not regulated by law, and have no set national nutrition standards. The Canadian scientific literature lacks quantitative information on the nutritional adequacy of school meals. Better and more evaluation of such programs would encourage and guide administrators to assess other local programs in a similar fashion. Here, we describe the dietary assessment process of 1 school meal program in Canada and the nutritional adequacy of the meals. Throughout 10 years (1997-2007), the contents of 159 lunches and 90 breakfasts were collected mainly from elementary schools participating in the Child Hunger and Education Program Good Food, Incs school nutrition program initiative in Saskatoon, Saskatchewan, Canada. We collected, weighed, and analyzed food samples from meals served to children at participating schools. We then compared their nutrient content against standards based on the Dietary Recommended Intakes for children aged 4 to 8 and 9 to 13 years using one third of the recommendations as the standard for lunches and one fourth for breakfasts. Overall, both meals had a good nutrient profile and met the standards for most analyzed macronutrients and micronutrients throughout the years. Although energy was persistently low, vitamin and mineral contents were often above the standards, reflecting a tendency to offer nutrient-dense foods in lieu of energy-dense foods. The rigorous methodology described in this manuscript can be followed to assess other small local programs. Furthermore, the dietary assessment presented can encourage not only the implementation of school meal programs in other locations but also the assessment of already existing programs-a clear need in the scientific literature.

Glycaemic response of proso millet-based (Panicum miliaceum) products

Abstract The glycaemic response of millet foods and the effect of processing are not known. Therefore, decorticated proso millet was used to produce four types of common food products (biscuits, couscous, porridge and an extruded snack). Postprandial blood glucose response of these products (all containing 50 g of total starch) was compared to the same foods produced with refined corn, in a crossover human study with 12 healthy male participants (age 26.3 ± 3.8 yr; BMI 23.3 ± 2.8 kg/m2). Capillary blood samples were collected and glycaemic response was determined; differences were assessed using repeat measures ANOVA. Overall, the mean (±SEM) incremental area under the blood glucose response curve (mmol min/l) of the proso millet products was different from the corn products, but individual products (couscous = 66.7 ± 11.6, biscuit = 82.6 ± 13.7, extrudate = 198.7 ± 20.9, porridge = 40.1 ± 5.8) were not significantly lower (couscous = 43.5 ± 5.8, biscuit = 102.0 ± 10.3, extrudate = 198.7 ± 20.9, porridge = 52.2 ± 8.1) (p > .05). Glycaemic response of the products was not dependent on the grain type, but rather product matrix. Graphical Abstract

Physicochemical and digestion characteristics of flour and starch from eight Canadian red and green lentils

Physicochemical and nutritional properties of flour and isolated starch from eight Canadian lentil cultivars were assessed to identify unique samples and key factors affecting starch digestion. The results showed that nearly half of apparent amylose in lentil flours was underestimated because it was complexed and embedded within the flour matrix, which led to slower starch digestion of cooked flour. Cooked red lentil flours showed significantly higher resistant starch content (11.0%) than flours from green lentils (6.8%) (P < 0.05). Among green lentils, Asterix and Greenland were unique for their high slowly digestible starch content after cooking, possibly owing to their high phenolic content and a-glucosidase inhibitory activity. Longand short-range ordering in starch was more indicative of low starch digestion for raw or cooked lentil flour rather than for isolated starch. The results suggest the flour matrix protects the starch ordered structure from enzyme hydrolysis.