Title: The Effect of Pea Flour Processing on the Nutritional Quality and End-product Quality of Extruded Breakfast Cereals Author(s): H.D. Maskus, L. Bourré, A. Sarkar, P. Ebbinghaus Citation: AACC International Annual Meeting, 23 October - 26 October 2016, Savannah, Georgia, U.S.A. Poster 808-P. Link: http://www.aaccnet.org/meetings/Documents/2016Abstracts/aacc2016abs182.htm

SIFTER

Flour

WholeCoarse

Semolina

Pin Mill15K rpm

REDUCINGROLLS

PurifierCoarse semo

PurifierFine semo

Fine semolinayield 22.2%

(~400µ)

Coarse semolina

yield 40.5%(600µm)

Sizing Rolls:Corrugated rolls to resize and scratch semolina

First Break:Corrugated rolls break peasinto coarse particles

Reduction Rolls:Smooth rolls reducing middlings to flour

Overs yield16.7%(hull

and shorts)

GrainBin

Pin Mill20K rpm

WholePea

Flour

SIFTER

SIFTER

IntroductionBreakfast cereals are currently viewed by consumers to be low in nutritional density, formulated with starchy, low protein ingredients. The objective of this study was to examine the effect of adding yellow pea ingredients varying in particle size and composition (whole pea and refined pea) on the nutritional differences of an extruded breakfast cereal product. Four pea ingredients were blended with corn meal, sugar, salt and pea fiber. A corn meal control containing sugar, fibre and salt was also included. Breakfast cereals were extruded and analyzed for nutritional and physical quality characteristics.

Materials and Methods

The Effect of Pea Flour Processing on the Nutritional Quality and End-product Quality of Extruded Breakfast CerealsH.D. Maskus, L. Bourré, A. Sarkar, P. Ebbinghaus Canadian International Grains Institute (Cigi), Winnipeg, Manitoba, Canada

@CigiWinnipeg cigi.caCigi

Figure 4: End-product quality characteristics of pea-based extruded breakfast cereals, bulk density, number of air cells and bowl life (statistical difference in breakfast cereal quality (p<0.05) is represented by different letters above like coloured columns for each pea ingredient type).

Figure 2: Mill process flow diagram to produce whole pea semolina, refined pea semolina, whole pea flour and refined pea flour.

Table 3: Nutritional quality of pea-based extruded breakfast cerealsControl* WPS RPS WPF RPF Retail Product*

Protein, % 5.5 15.1 ± 0.1a 15.8 ± 0.0a 12.9 ± 0.4c 13.8 ± 0.1b 3.5

Total dietary fibre, % as is

8.2 16.3 ± 0.4a 11.6 ± 0.4b 16.2 ± 0.1a 12.6 ± 0.1b 10.8

Iron, mg/100g as is 1.3 4.1 ± 0.0ab 3.8 ± 0.0b 4.7 ± 0.1a 4.5 ± 0.3ab 29.8

Potassium, mg/100g 146 613.0 ± 11.3a 628.5 ± 0.7a 525.0 ± 22.6b 548.0 ± 1.4b 125

Niacin, mg/100g as is 1.6 2.3 ± 0.5a 2.9 ± 0.4a 1.5 ± 0.6a 2.1 ± 0.4a 4.0

Thiamine, mg/100g as is

0.1 0.5 ± 0.0ab 0.6 ± 0.1a 0.4 ± 0.0b 0.5 ± 0.0ab 4.1

Riboflavin, mg/100g as is

0.1 0.1 ± 0.0a 0.1 ± 0.0a 0.1 ± 0.0a 0.1 ± 0.0a 0.1

Folate*, ug/100g as is 31.08 <5.0 13.0 14.1 8.2 69.48* data not available for statistical analysis Values with the same letter within a row are not statistically different (p<0.05)

Results and DiscussionResults of the nutritional analysis of pea-based breakfast cereals, corn meal based control and retail samples are presented in Table 3. Pea ingredients significantly affected nutritional composition of pea-based breakfast cereals. Protein content of cereals produced from pea semolina ingredients (WPS and RPS) contained significantly more protein than cereals made from pea flour ingredients. This was due to the increased amount of protein in the pea semolina ingredients as semolina is produced from the outermost layers of the pea seed with higher concentration of protein in these layers while flours are typically generated from the inner portion of the seed which are lower in protein. Fibre was found to be significantly higher (p<0.05) in the whole pea ingredients (WPS and WPF) as these ingredients contained pea hull, a fibre rich portion of the pea seed. With

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Bulk density (g/L) No. of air cells Bowl life (s)

ConclusionsThese results indicate that pea ingredients can be used to improve the nutrient density of corn based breakfast cereal products. In addition, processing conditions of the pea ingredients can also affect nutrient content as well as end-product quality characteristics of pea based breakfast cereals. Overall, refined pea semolina contained the highest nutrient contents for protein, potassium, niacin and thiamine while WPS contained the highest fibre content and WPF contained the highest iron and folate content. RPS also had the best physical quality characteristics of the pea ingredient based breakfast cereals (low bulk density, high number of air cells and extended bowl life). When selecting pea ingredients to improve breakfast cereal nutritional quality, a refined semolina ingredient should be selected to achieve the greatest product quality in breakfast cereals.

References AACC International. Approved Methods of Analysis, 11th Ed. Method 76.13.01. Total starch assay procedure (Megazyme amyloglucosidase/α-amylase method). Approved November 3, 1999. AACC International, St. Paul, MN, U.S.A. http://dx.doi.org/10.1094/AACCIntMethod-76-13.01

AOAC International. (1995). Official Methods of Analysis. Methods 942.23, 944.13, 960.46, 970.65, 981.15, 991.43, 2011.06, 2011.14. Gaithersburg, MD, U.S.A.

Williams, P., Sobering, D., and Antoniszyn, J. (1998). Protein testing methods at the Canadian GrainCommission. In Wheat Protein, Production and Marketing. Proceedings of the Wheat ProteinSymposium. (pp.37-47). Saskatoon, SK: University of Saskatchewan Press.

Rawle, A. (n.d.). Basic principles of particle size analysis. http://www.malvern.com/malvern/kbase.nsf/allbyno/KB000021/$file/Basic_principles_of_particle_size_analysis_MRK034-low_res.pdf. Accessed September17th, 2013.

Acknowledgements Funding for this project has been provided by Pulse Canada and by Agriculture and Agri-Food Canada through the Canadian Agricultural Adaptation Program. The technical assistance provided by Cigi’s milling, extrusion and analytical services staff is greatly appreciated. Special thanks to Cigi’s Communications staff for poster design and layout.

Project funding by:

Analyses: Protein, Dietary Fibre, Iron, Potassium, Folate, Niacin,Thiamine, Riboflavin, Bulk Density, Number of Air Cells, Bowl Life

WholeYellowPeas

Bühler PilotScale Roller

Milling

BlendingBreakfast

CerealFormulations

BreakfastCereal

ExtrusionProcessing

• Refined Pea Semolina (RPS)• Whole Pea Semolina (WPS)• Refined Pea Flour (RPF)• Whole Pea Flour (WPF)

• 31.5% Corn Meal

• 56.5% Pea Flour/semo

• 6.5% Pea Fibre

• 0.5% Salt

• 5% Sugar

Figure 1: Process flow diagram for processing whole yellow pea to extruded direct expanded breakfast cereal

Whole Yellow Peas (23.7% protein dwb) were roller milled at the Cigi using a Bühler Pilot Scale roller mill (Bühler AG, Uzwil Switzerland). Four pea ingredients were produced including whole pea semolina (WPS), refined pea semolina (RPS), whole pea flour (WPF) and refined pea flour (RPF). The mill process flow diagram used to produce pea ingredients is illustrated in Figure 2 while characteristics of the pea ingredients are outlined in Table 1.

Figure 3: Pea-based breakfast cereals L to R whole pea semolina, refined pea semolina, whole pea flour and refined pea flour

Milled products were analyzed for moisture, protein, total dietary fibre, total starch, starch damage, and particle size distribution which can be found in Table 1. Pea ingredients were blended with other ingredients according to the formulation listed in Table 2.

Each of the pea-based formulations and a control, corn based formulation were processed using a Clextral EV25 twin screw extruder (Firminy, France) to produce a direct expanded breakfast cereal product. End products were evaluated for protein Williams et al (1998) dietary fiber (AOAC 991.43 with modifications), iron (AOAC 2011.14), potassium (AOAC 2011.14), folate (AOAC 2011.06), niacin (AOAC 944.13, AOAC 960.46, Microbiological Methods), thiamine (AOAC 942.23, 970.65 and 981.15) and riboflavin (AOAC 942.23, 970.65 and 981.15) content as well as bulk density (g/L) , number of air cells (C-Cell, Warrington, UK), and bowl life (s). Significant differences among treatments were determined using the JMP statistical analysis software (11.0.0) from SAS Institute Inc (Cary North Carolina) using a Student’s t-test (p<0.05).

regard to micronutrients, iron content was highest in the WPF cereal product but was only significantly greater than the RPS cereal. Potassium content was highest in the semolina based cereals. Thiamine content was highest in the RPS cereal but was only significantly higher than the WPF based cereal. No significant differences were observed for niacin and riboflavin content between the different pea ingredient breakfast cereals.

Nutritional values for a control breakfast cereal processed at Cigi and a retail product have been included in Table 3 for comparison purposes. With the exception of folate, all nutrient contents in pea-based breakfast cereals were greater than those in the corn based control breakfast cereal. When compared to a retail breakfast cereal product, protein, fibre and potassium levels were all greater in pea-based samples. Other nutrient levels were higher in retail samples as these products are often fortified with these nutrients.

Pea ingredient type also had an effect on the physical quality characteristics of breakfast cereals as seen in Figure 4. Bulk density was lowest in RPS and WPF which were significantly lower than WPS and RPF. Typically, the presence of increased amounts of fibre leads to increased bulk density in extruded products. Bulk density of retail breakfast cereals and the control sample was 157.7±0.6 g/L and 163.0 ± 2.8 g/L respectively. The number of air cells in the cereals also varied with the pea-ingredient base used. RPS and WPF both had significantly greater number of air cells compared to WPS. The number of air cells in the cross sectional area of the retail breakfast cereal and control breakfast cereal was 107.0 ± 13.1 cells and 83.0 ± 14.1 cells respectively. No significant differences were observed between cereal samples for their bowl life. Overall, these results demonstrate that pea ingredient quality can have a significant effect on both the nutritional quality and physical quality of breakfast cereals developed when pea ingredients are used as a base ingredient.

Table 1: Pea ingredient quality characteristics

WPS RPS WPF RPF

Protein, % dwb 25.7 26.7 21.7 22.5

Moisture, % 11.0 11.3 10.5 10.9

Total dietary fibre, % as is basis 20.2 9.5 14.8 7.8

Total starch, % dwb 37.4 36.1 52.0 58.2

Starch damage, % dwb 0.7 0.6 3.2 3.7

Particle Size Distribution

d(0.1) 340.4 435.2 14.8 15.1

d(0.5) 606.0 650.9 51.4 42.1

d(0.9) 944.9 986.7 340.6 126.9

d(4.3) 613.3 686.3 116.5 58.2

Table 2: Pea-based breakfast cereal formulation

Ingredient % of Main Ingredient % of Total

Pea ingredient 100.0 56.7

Corn meal (Bunge) 55.5 31.4

Pea fibre (Best Cooking Pulses) 11.8 6.7

Sugar (Roger’s) 8.8 5.0

Salt 0.8 0.5