LOW-GLYCEMIC INDEX USING PULSE INGREDIENTS NORTHERN PULSE GROWERS ASSOCIATION

Transcription

1 LOW-GLYCEMIC INDEX USING PULSE INGREDIENTS NORTHERN PULSE GROWERS ASSOCIATION

2 THE FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS DECLARED 2016 THE INTERNATIONAL YEAR OF PULSES DEVELOPMENT OF LOW-GLYCEMIC INDEX PRODUCTS USING PULSE INGREDIENTS Pulses, which are members of the legume family, include lentils, chickpeas, and dry peas. On a global level, pulses increasingly are being recognized for their role as a nutritious food source that promotes good health. As a result of their role in providing nutrition and promoting food security, the Food and Agriculture Organization of the United Nations declared 2016 as the International Year of Pulses. Pulses are versatile, easy-to-prepare ingredients that can be used in entrees, salads, breads, desserts and other menu applications. Researchers have reported that regular consumption of pulses may reduce the risk of heart disease, diabetes and certain types of cancer. On average, North Dakota and Montana produce 71% of the pulse crop in the United States. 2

3 PULSE INGREDIENTS HAVE BEEN USED IN SNACKS, BAKERY PRODUCTS, SOUP, MEAT SUBSTITUTES, BABY FOOD, ICE CREAM AND DESSERTS, SAUCES AND SEASONING, PASTA AND NOODLES. FOOD APPLICATIONS OF PULSE INGREDIENTS Pulses can be fractionated into their components through special processing. Pulse ingredients, such as flour, protein, starch, and fiber, have a wide range of product applications. Pulse ingredients have been used in snacks, bakery products, soup, meat substitutes, baby food, ice cream and desserts, sauces and seasoning, pasta and noodles. For example, in glutenfree applications, pulse flour can improve the nutritional profile as a result of its protein, fiber and vitamin and mineral content. GLYCEMIC RESPONSE Along with their nutritional value, pulse ingredients are recognized for their low glycemic response or effect on blood sugar levels. Jenkins (1981) introduced the glycemic index (GI) system for foods. The GI is a measure of the effect of foods in raising blood sugar (glucose) levels after a meal. Some research has shown an association between low-gi foods and decreased risk of type 2 diabetes, obesity, cardiovascular disease, metabolic syndrome, stroke, and other chronic diseases. RESEARCH OBJECTIVES AND METHODS The Northern Pulse Growers Association, Bismarck, ND, collaborated with the Northern Crops Institute, Fargo, ND, North Dakota State University, Fargo, ND, and Glycemic Index Labs, Toronto, ON, to conduct research related to the influence of pulses on the GI of food formulated with pulse ingredients. The objectives of the project were 1) to develop new low- GI products with pulse flours including pasta, cookies, muffins, bread, crackers, quick bread, and extruded snack and snack bars; and 2) to provide in vivo evidence showing the benefit of pulse flour on glycemic response. Pasta, extruded snacks, bread, crackers, cookies, bars and muffin formulations were developed to contain pulse ingredients, including yellow pea flour, green or red lentil flour, pea protein, and/or pea fiber (bran). Ninety-four samples were tested for in vitro GI, total starch (TS) and resistant starch (RS) using standard methods. After preliminary testing, 10 samples, including five controls without added pulse ingredients, were selected for further GI testing. Proximate analysis was conducted using official AOAC methods. Glycemic load (GL) was calculated by multiplying GI by available carbohydrate and dividing by 100. GI testing and palatability testing were conducted on the following products: White Bread Control, Pasta Control, Pasta Red Lentil, Focaccia Control, Focaccia Lentil, Shortbread Chocolate Cookie Control, Shortbread Chocolate Yellow Pea Protein and Fiber, Baked Granola Bar Control, Baked Granola Bar Protein Puff, Seedy Crisp Cracker Control, and Seedy Crisp Cracker Pea. The Glycemic Index Labs, Toronto, ON, conducted the in vivo GI testing. Ten subjects (ages 18 to 75) in good health participated in the in vivo testing. After a 10- to 14-hour overnight fast, the subjects were weighed and two fasting blood samples were obtained. After having a test meal with white bread or glucose as a reference, blood samples were obtained at 15, 30, 45, 60, 90 and 120 minutes. A limitation of the research was the relatively small number of subjects in the in vivo study. For more information about the preliminary results, please contact the Northern Pulse Growers Association ( and the Northern Crops Institute ( 4

4 PASTA CONTROL AND PASTA RED LENTIL Ingredient Control % Pulse variant % Semolina Decorticated red lentil flour 0 50 FOCACCIA CONTROL AND FOCACCIA GREEN LENTIL Ingredient Control Pulse variant g % g % Flour Water Extra virgin olive oil Olive oil (topping) Instant yeast Salt Garlic powder Sea salt, fine Black pepper, fine Dried herb Decorticated green lentil flour Total FORMULATIONS SHORTBREAD CHOCOLATE COOKIE CONTROL, SHORTBREAD CHOCOLATE YELLOW PEA PROTEIN AND FIBER Ingredient Control Pulse variant g % g % Unsalted butter Pastry flour Sugar Dutched cocoa powder Salt Vanilla Baking powder Decorticated green lentil flour Pea bran (PB) Pea protein (PP) Total

5 BAKED GRANOLA BAR CONTROL AND BAKED GRANOLA BAR PROTEIN PUFF Ingredient Control Pulse variant g % g % Coconut oil Agave syrup Sugar Vanilla Cinnamon Rice Krispies Pulse Puff* GL Puff PP + PF High Grape nuts cereal Pastry flour Decorticated green lentil flour Sunflower seeds Rolled oats Cinnamon chips Total *PULSE PUFFS USED IN THE GRANOLA Ingredient GL Puff PP + PF High Corn cones 29.5 Decorticated green lentil 35 Pea protein (PP) 30 Pea fiber (bran) (PF) 5 Calcium carbonate 0.5 Total 100 SEEDY CRISP CRACKER CONTROL AND CRACKERS WITH PEA PROTEIN Ingredient Control Pulse variant g % g % Whole wheat flour All-purpose flour Pea protein isolate Poppy seed Sesame seed Salt Garlic powder Baking soda Olive oil Water Total

6 PALATABILITY RATINGS The graph below shows the palatability results of samples with and without the addition of pulse ingredients. Overall, no significant differences were shown in palatability when pulse ingredients were added to control formulations. NUTRIENT ANALYSES The proximate analyses (protein, fat, carbohydrate (CHO), fiber and available carbohydrate) of the samples used in in vivo testing indicate differences among samples (shown below). The test meal weights were standardized to provide 50 grams of available carbohydrate (total carbohydrate minus fiber). 100 PALATABILITY (mm) BR01 BR03 CR04 CR05 GB23 GB24 PA01 PA14 SB12 SB16 Palatability scores after consumption of Focaccia Control (BR01), Focaccia Lentil (BR03), Seedy Crisp Cracker Control (CR04), Seedy Crisp Cracker Pea (CR05), Baked Granola Bar Control (GB 23), Baked Granola Bar Protein Puff (GB24), Pasta Control (PA01), Pasta Red Lentil (PA14), Shortbread Chocolate Cookie Control (SB12), Shortbread Chocolate Cookie Yellow Pea + Protein + Fiber (SB 16). The control products are in green, pulse variants are in yellow and the white bread control is in gray. Data are expressed as Mean + SEM. WB Nutrient analysis of food samples used in vivo GI testing. (All measurements in grams.) Test Meal Weight Protein Fat Total CHO Fiber Available CHO White Bread Control Pasta Control Pasta Red Lentil Focaccia Control Focaccia Lentil Shortbread Chocolate Cookie Control Shortbread Chocolate Pea Protein and Fiber Baked Granola Bar Control Baked Granola Protein Puff Seedy Crisp Cracker Control Seedy Crisp Cracker Pea

7 IN VITRO AND IN VIVO GLYCEMIC INDEX DETERMINATION Using the classification of ISO 26642:2010, products with a glycemic index (GI) less than or equal to 55 are classified as being Low GI, those with a GI of 56 to 69 are classified as Medium GI, while those with a GI equal to or greater than 70 are High GI. The estimated GI, GI and GL were predominantly in the Low GI category (shown below). With the exception of the granola bars, a reduction of GI was found in all 10 foods through the in vitro GI index testing. Specifically, the GI category changed from Medium to Low in both pasta and focaccia products. Summary of in vitro and in vivo glycemic index testing of 10 samples and white bread control. Product Estimated Index Glycemic Index Glycemic Load GI Category WITH THE EXCEPTION OF THE GRANOLA BARS, A REDUCTION OF GI WAS FOUND IN ALL 10 FOODS THROUGH THE IN VITRO GI INDEX TESTING. White Bread Control NA High Pasta Control Medium Pasta Red Lentil Low Focaccia Control Medium Focaccia Lentil Low Shortbread Chocolate Cookie Control Low Shortbread Chocolate Pea Protein and Fiber Low Baked Granola Bar Control Low Baked Granola Bar Protein Puff Low Seedy Crisp Cracker Control Low Seedy Crisp Cracker Pea Low 12

8 SUMMARY: RESEARCH TO PRACTICE In vitro testing showed decreases in estimated GI in all products except granola bars. According to the results of in vivo testing, two of the ten food products (pasta with added decorticated red lentil flour and focaccia bread with added decorticated red lentil flour) showed a reduction in their GI category from medium to low. In all cases, adding pulse ingredients did not affect the palatability scores and can improve the nutritional profile of food products by increasing fiber and protein content. REFERENCES Campos-Vega, R., Loarca-Pina, G., & Oomah, B. (2010). Minor components of pulses and their potential impact on human health. Food Research International, 43, Gebrelibanos, M., Tesfaye, D., Raghavendra, Y., & Sintayeyu, B. (2013). Nutritional and health implications of legumes. International Journal of Pharmaceutical Sciences and Research, 4(4), Goni, I., & Valentin-Gamazo, C. (2003). Chickpea flour ingredient slows glycemic response to pasta in healthy volunteers. Food Chemistry, 8, Jenkins, D.J., Wolever, T.M., Taylor, R.H., Barker, H., Fielden, H., Baldwin, J.M, Bowling, A.C., Newman, H.C., Jenkins, A.L., & Goff, D.V. (1981). Glycemic index of foods: a physiological basis for carbohydrate exchange. American Journal of Clinical Nutrition, 34(3), Khan, I., Tabassum, F., & Khan, A. (2008). Glycemic indices and glycemic loads of various types of pulses. Pakistan Journal of Nutrition, 7(1), Mitchell, D., Lawrence, F., Hartman, T., & Curran, J. (2009). Consumption of dry beans, peas, and lentils could improve diet quality in the U.S. population. Journal of the American Dietetic Association, 109(5), Mollard, R., Wong, C., Luhovyy, B., & Anderson, G. (2011). First and second meal effects of pulses on blood glucose, appetite, and food intake at a later meal. Applied Physiology, Nutrition and Metabolism, 36, Rochfort, S., & Panozzo, J. (2007). Phytochemicals for health, the role of pulses. Journal of Agricultural and Food Chemistry, 55(20), ADDING PULSE INGREDIENTS DID NOT AFFECT THE PALATABILITY SCORES AND CAN IMPROVE THE NUTRITIONAL PROFILE OF FOOD PRODUCTS BY INCREASING FIBER AND PROTEIN CONTENT. Roy, F., Boye, J., & Simpson, B. (2010). Bioactive proteins and peptides in pulse crops: Pea, chickpea and lentil. Food Research International, 43,

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