Glycemic Potential of Extruded Barley, Cassava, Corn, and Quinoa Enriched With Whey Proteins and Cashew Pulp

Figures & data

Table 1 Proximate composition of starch materials blended with whey protein concentrate (W) and cashew pulp (CP)

Product	Dry matter (g)	Protein	Fat	Ash	Fiber
Barley	92.2	13.4	2.1	1.4	0.8
Barley_W	92.5	19.6	2.6	1.4	0.5
Baarley_W_C	92.4	18.6	2.3	1.5	1.6
Corn	92.3	6.6	1.4	0.0	0.0
Corn_W	92.3	14.9	1.3	0.4	0.0
Corn_W_C	92.8	16.3	2.5	0.8	1.6
Cassava	90.0	1.4	0.5	0.4	1.0
Cassava_W	90.0	9.8	1.0	0.6	0.9
Cassava_W_C	90.1	6.5	0.9	0.9	2.4
Quinoa	91.9	13.2	6.8	2.4	0.6
Quinoa_W	92.4	21.5	6.8	2.0	1.0
Quinoa_W_C	92.4	22.2	7.1	2.2	2.2
_W: Product with whey protein concentrate: WPC80 blended in at 12.5 wt%; _W_C: Product with whey protein concentrate: WPC80 blended in at 12.5 wt%, and cashew pulp: CP blended in at 12.5 wt%. Carbohydrate value is calculated by difference. Cashew pulp contained 5% moisture, 1.5% fat, 9% protein, 1.7% ash, 41% non soluble fiber, and carbohydrate the difference.

Figure 1 Photographs of Baked barley (A), cassava (B), corn (C), and quinoa (D); illustrating natural colorations and peculiar expansion modes of crusted tops with pillow-like expansion of the products.

Figure 2 Photographs of baked barley products (A) control, (B) barley with whey protein concentrate, 80% protein (WPC80), and (C) Barley with WPC80 and Cashew Pulp (CP). Typical shrinkage and uneven puffing with associated with WPC80, and intense discoloration with WPC80 and CP.

Figure 3 Confocal scanning laser micrographs of partially-cooked (half-products) of barley (A), cassava (B), corn (C), and quinoa (D); showing distribution of protein bodies, starch, and protein-starch complex.

Figure 4 Confocal scanning laser micrographs of partially-cooked (half-products) barley (A), barley with whey protein concentrate, 80% protein (WPC80), and (C) Barley with WPC80 and Cashew Pulp (CP); showing distribution of protein bodies, starch, and protein-starch complex, and CP fiber as long slender lines.

Table 2 Physical properties and glycemic responses of barley, whey protein concentrate (WPC80), and cashew pulp (CP) products.*

Material	Moisture content (%)	WSI	WAI	Peak viscosity (cP)	Breakdown viscosity (cP)	Peak temp gelatinization (°C)	Percent gelatinized from raw	Glycemic potential 20 min	Glycemic potential 120 min
Barley	9.9	0.07^c	1.97^c	746.3^a	274.3^b,c	66.1
Barley extruded	34.6	0.09^c	4.88^a	473.4^b	400.9^a,b	55.7	90.3^a	61.2	60.9
Barley_W	9.9	0.16^b	1.81^c	471.0^b,c	147.0^c,d	78.6
Barley_W extruded	37.4	0.07^c	4.24^b	574.0^a,b	509.9^a	60.6	26.6^b	54.1	58.2
Barley_W_C	10.4	0.19^a	1.84^c	341.6^b,c	74.5^d	82.3
Barley_W_C extruded	39.4	0.09^c	3.99^b	271.7^c	237.4^c,d	50.1**	98.0^a	42.0	60.8
Barley_W: Barley with whey protein concentrate WPC80 blended in at 12.5 wt%; Barley_W_C: Barley with whey protein concentrate WPC80 blended in at 12.5 wt% and cashew pulp: CP blended in at 12.5 wt%. *: Mean values in a given column with no letter in common are significantly different (p < 0.05) by the Bonferroni LSD technique. **: Peak gelatinization values for extremely weak paste.

Table 3 Physical properties of baked or fried extruded barley, whey protein concentrate (WPC80) or cashew pulp (CP) half-products.*

Material	Moisturecontent (%)	Bulk density (g/cm^3)	Particle density (g/cm^3)	Apparent porosity (%)	Volume expansion (%)	Hardness (N)
Barley (Baked)	1.9^b	0.4^b	1.3	69.7	324.9	13.7^b
Barley (Fried)	16.1^a	1.0^a	1.4	27.4	141.7	227.6^a
Barley_W (Baked)	1.2^b	0.5^ab	1.4	63.7	207.9	11.6^b
Barley_W (Fried)	17.0^a	0.6^ab	1.4	58.3	320.7	153.5^a
Barley_W_C (Baked)	1.5^b	0.4^b	1.4	72.8	241.7	16.2^b
Barley_W_C (Fried)	15.4^a	0.6^ab	1.4	55.0	152.3	209.7^a
Barley_W: Barley with whey protein concentrate (12.5 wt%); Barley_W_C: Barley with whey protein concentrate (12.5 wt%) and cashew pulp (12.5 wt%). Barley (Extruded), Moisture (34.6 ± 4.5), Bulk density (1.4 ± 0.0), Particle Density (1.3 ± 0.0), Apparent porosity (54.2 ± 0.0), Volume expansion, not determined), and Hardness (4.9 ± 0.1), Barley_W (Extruded), Moisture (37.4 ± 1.5), Bulk density (1.0 ± 0.7), Particle Density (1.3 ± 0.0), Apparent porosity (65.0 ± 0.0), Volume expansion, not determined), and Hardness (4.2 ± 0.3), Barley_W_C (Extruded), Moisture (39.4 ± 1.9), Bulk density (0.9 ± 0.5), Particle Density (1.3 ± 0.0), Apparent porosity (59.3 ± 0.0); Volume expansion (not determined), and Hardness (4.0 ± 0.3). *: Mean values in a given column with no letter in common are significantly different (p < 0.05) by the Bonferroni LSD technique.

Table 4 Physical properties and glycemic responses of cassava, whey protein concentrate (WPC80), and cashew pulp (CP) products.*

Material	Moisture content (%)	WSI	WAI	Peak viscosity (cP)	Breakdown viscosity (cP)	Peak temp gelatinization (°C)	Gelatinized from raw (%)	Glycemic potential 20 min (%)	Glycemic potential 120 min (%)
Cassava	11.2	0.03^b	2.62^b	2812.0^a	1244.7^a	64.3
Cassava (Extruded)	19.8	0.26^a	5.15^a	121.0^d	99.6^c	52.7	42.4	48.5	72.4
Cassava_W	10.7	0.13^ab	2.30^b	1792.3^b	435.5^b	67.4
Cassava_W (Extruded)	16.9	0.27^a	4.89^a	69.3^d	65.4^c	**	40.7	77.1	70.7
Cassava_W_C	7.9	0.15^a	2.49^b	1219.3^c	253.3^bc	68.6
Cassava_W_C (Extruded)	19.5	0.24^a	4.79^a	65.2^d	64.6^c	^**	45.6	60.9	56.5
Cassava_W: Cassava with whey protein concentrate WPC80 blended in at 12.5 wt%; Cassava_W_C: Cassava with whey protein concentrate WPC80 blended in at 12.5 wt% and cashew pulp: CP blended in at 12.5 wt%. *: Mean values in a given column with no letter in common are significantly different (p < 0.05) by the Bonferroni LSD technique. **: Undetermined peak gelatinization values for extremely weak paste.

Table 5 Physical properties of baked or fried extruded cassava, whey protein concentrate or cashew pulp half-products.*

Material	Moisture content (%)	Bulk density (g/cm^3)	Particle density (g/cm^3)	Apparent porosity (%)	Volume expansion (%)	Hardness (N)
Cassava (Baked)	9.8^b	0.8	1.48^b	42.4	216.5	142.3^ab
Cassava (Fried)	16.9^a	0.9	1.51^b	41.8	249.2	339.7^a
Cassava_W (Baked)	8.6^bc	1.0	1.51^b	34.2	196.5	128.8^ab
Cassava_W (Fried)	13.8^a	1.0	1.51^b	33.8	211.9	312.5^a
Cassava_W_C (Baked)	5.8^c	0.8	1.47^b	43.2	222.8	41.7^b
Cassava_W_C (Fried)	14.7^a	1.0	1.72^a	45.5	215.8	*
Cassava_W: Cassava with whey protein concentrate (12.5 wt%); Cassava_W_C: Cassava with whey protein concentrate (12.5 wt%) and cashew pulp (12.5 wt%); Cassava (Extruded), Moisture (19.8 ± 3.4), Bulk density (1.9 ± 0.9), Particle Density (1.4 ± 0.0), Apparent porosity (18.5 ± 0.0), Volume expansion, not determined), and Hardness (270.8 ± 43.2); Cassava_W (Extruded), Moisture (17.0 ± 0.7), Bulk density (1.8 ± 0.8), Particle Density (1.4 ± 0.0), Apparent porosity (13.3 ± 0.0), Volume expansion, not determined), and Hardness (383.0 ± 86.2); Cassava_W_C (Extruded), Moisture (19.5 ± 0.9), Bulk density (2.0 ± 1.3), Particle Density (1.5 ± 0.0), Apparent porosity (32.7 ± 0.0); Volume expansion (not determined), and Hardness (308.3 ± 47.5). *:Mean values in a given column with no letter in common are significantly different (p < 0.05) by the Bonferroni LSD technique.

Table 6 Physical properties and potential glycemic responses of corn, whey protein concentrate (WPC80), and cashew pulp (CP) products.*

Material	Moisture content (%)	WSI	WAI	Peak viscosity (cP)	Breakdown viscosity (cP)	Peak temp gelatinization (°C)	Gelatinized from raw (%)	Glycemic potential 20 min (%)	Glycemic potential 120 min (%)
Corn	11.1	0.02^c	2.45^ab	353.7^a	98.7^c	77.7
Corn (Extruded)	24.0	0.05^bc	4.61^a	244.4^ab	206.0^a	50.1**	52.0	54.3	75.2
Corn_W	10.9	0.11^a	2.22^b	209.3^bc	47.3^d	83.9
Corn_W (Extruded)	21.2	0.06^abc	4.16^ab	154.4^c	130.2^b	50.1**	50.4	54.6	76.0
Corn_W_C	12.5	0.14^a	2.26^ab	127.5^bc	29.0^d	84.8
Corn_W_C (Extruded)	21.0	0.07^ab	3.83^ab	107.6^c	84.9^cd	60.6	52.2	47.6	79.0
Corn_W: Corn with whey protein concentrate WPC80 blended in at 12.5 wt%; Corn_W_C: Corn with whey protein concentrate WPC80 blended in at 12.5 wt% and cashew pulp: CP blended in at 12.5 wt%. *: Mean values in a given column with no letter in common are significantly different (p < 0.05) by the Bonferroni LSD technique. **: Peak gelatinization values for extremely weak paste.

Table 7 Physical properties of baked or fried extruded corn, whey protein concentrate or cashew pulp half-products.*

Material	Moisture content (%)	Bulk density (g/cm^3)	Particle density (g/cm^3)	Apparent porosity (%)	Volume expansion (%)	Area (N·mm)	Hardness (N)
Corn (Baked)	3.7^c	0.70^ab	1.29^ab	45.7	205.5	3.6^b	18.3^b
Corn (Fried)	10.9^a	0.71^ab	1.30^a	46.0	172.0	133.1^a	99.3^a
Corn_W (Baked)	2.5^d	0.87^a	1.32^a	34.0	145.2	4.6^b	19.2^b
Corn_W (Fried)	11.5^a	0.53^ab	1.29^a	59.3	194.0	72.4^ab	64.2^ab
Corn_W_C (Baked)	1.3^e	0.88^a	1.31^a	32.6	129.1	7.4^b	23.4^b
Corn_W_C (Fried)	8.7^b	0.36^b	1.25^b	70.9	284.3	28.2^b	34.5^b
Corn_W: Corn with whey protein concentrate (12.5 wt%); Corn_W_C: Corn with whey protein concentrate (12.5 wt%) and cashew pulp (12.5 wt%); Corn (Extruded), Moisture (24.0 ± 2.1), Bulk density (1.1 ± 0.4), Particle Density (1.3 ± 0.0), Apparent porosity (14.4 ± 0.0), Volume expansion, not determined), and Hardness (349.5 ± 18.0); Corn_W (Extruded), Moisture (21.2 ± 1.4), Bulk density (1.0 ± 0.3), Particle Density (1.4 ± 0.0), Apparent porosity (10.7 ± 0.0), Volume expansion, not determined), and Hardness (360.4 ± 75.4); Corn_W_C (Extruded), Moisture (21.0 ± 1.0), Bulk density (1.1 ± 0.5), Particle Density (1.3 ± 0.0), Apparent porosity (49.9 ± 0.0); Volume expansion (not determined), and Hardness (339.5 ± 52.4). *: Mean values in a given column with no letter in common are significantly different (p < 0.05) by the Bonferroni LSD technique.

Table 8 Physical properties and potential glycemic responses of Quinoa, whey protein concentrate (WPC80), and cashew pulp (CP) products.*

Material	Moisture content (%)	WSI	WAI	Peak viscosity (cP)	Breakdown viscosity (cP)	Peak temp gelatinization (°C)	Percent gelatinizedfrom raw	Glycemic potential 20 min (%)	Glycemic potential 120 min (%)
Quinoa (Raw)	10.8	0.08^bc	2.02^b	300.7^b	15.7^d	68.4
Quinoa (Extruded)	19.6	0.06^c	5.47^a	465.2^a	360.3^a	53.0	57.9	70.3	65.3
Quinoa_W (Raw)	10.8	0.16^a	2.01^b	208.0^c	26.2^d	87.2
Quinoa_W (Extruded)	19.7	0.08^b	4.95^ab	284.4^b	251.6^b	52.1	60.1	69.5	72.8
Quinoa_W_C (Raw)	11.4	0.18^a	2.06^b	115.7^d	21.2^d	85.6
Quinoa_W_C (Extruded)	19.6	0.09^b	4.62^b	190.1^cd	167.2^c	52.5	90.0	59.6	53.0
Quinoa_W: Quinoa with whey protein concentrate WPC80 blended in at 12.5 wt%; Quinoa_W_C: Quinoa with whey protein concentrate WPC80 blended in at 12.5 wt% and cashew pulp: CP blended in at 12.5 wt%. *: Mean values in a given column with no letter in common are significantly different (p < 0.05) by the Bonferroni LSD technique.

Table 9 Physical properties of baked or fried extruded quinoa, whey protein concentrate (WPC80) or cashew pulp (CP) half-products.*

Material	Moisture content (%)	Bulk density (g/cm^3)	Particle density (g/cm^3)	Apparent porosity (%)	Volume expansion (%)	Area (N·mm)	Hardness (N)
Quinoa (Baked)	3.3^c	0.61^a	1.42^a	56.8	298.1	5.3^c	25.6^c
Quinoa (Fried)	15.0^a	0.76^a	1.40^a	45.6	247.7	118.2^a	94.2^a
Quinoa_W (Baked)	2.9^c	0.59^a	1.41^a	58.4	305.0	7.6^c	29.1^c
Quinoa_W (Fried)	11.2^ab	1.04^a	1.42^a	26.9	141.3	57.4^b	59.6^b
Quinoa_W_C (Baked)	1.8^c	0.63^a	1.41^a	54.9	181.3	6.4^c	24.6^c
Quinoa_W_C (Fried)	10.7^b	0.70^a	1.41^a	50.7	130.3	39.9^b	45.9^bc
Quinoa_W: Quinoa with whey protein concentrate (12.5 wt%); Quinoa_W_C: Quinoa with whey protein concentrate (12.5 wt%) and cashew pulp (12.5 wt%). Quinoa (Extruded), Moisture (19.6 ± 1.0), Bulk density (1.9 ± 1.3), Particle Density (1.4 ± 0.0), Apparent porosity (30.2 ± 0.0), Volume expansion, not determined), and Hardness (245.4 ± 36.5); Quinoa_W (Extruded), Moisture (19.7 ± 0.7), Bulk density (1.4 ± 0.5), Particle Density (1.4 ± 0.0), Apparent porosity (17.4 ± 0.0), Volume expansion, not determined), and Hardness (218.9 ± 36.6); Quinoa_W_C (Extruded), Moisture (19.6 ± 1.6), Bulk density (0.9 ± 0.4), Particle Density (1.4 ± 0.0), Apparent porosity (10.4 ± 0.0); Volume expansion (not determined), and Hardness (280.9 ± 39.8). *: Mean values in a given column with no letter in common are significantly different (p < 0.05) by the Bonferroni LSD technique.