Granular structure, physicochemical and rheological characteristics of starch from yellow cassava (Manihot esculenta) genotypes

Figures & data

Table 1. Chemical composition of starch from seven yellow cassava cultivars (%db).

Cultivar	Total starch (%)	Protein (%)	Fat (%)	Ash (%)	Crude fiber
S1	98.72 ± 0.10^bc	0.01 ± 0.01^a	0.02 ± 0.01^a	0.03 ± 0.10^a	0.05 ± 0.01^b
S2	99.03 ± 0.10^c	ND	0.01 ± 0.01^a	0.02 ± 0.01^a	0.02 ± 0.01^a
S3	98.13 ± 0.11^b	0.10 ± 0.01^a	0.01 ± 0.01^a	0.11 ± 0.01^b	0.10 ± 0.05^c
S4	98.48 ± 0.12^b	0.10 ± 0.01^a	0.07 ± 0.01^b	0.15 ± 0.01^c	0.20 ± 0.04^c
S5	97.91 ± 0.23^a	ND	0.04 ± 0.02^ab	0.10 ± 0.01^b	0.15 ± 0.01^c
S6	99.01 ± 0.04^bc	0.01 ± 0.01^a	0.02 ± 0.01^a	0.02 ± 0.01^a	0.01 ± 0.01^a
S7	98.59 ± 0.31^b	0.05 ± 0.01^b	0.01 ± 0.01^a	0.01 ± 0.01^a	0.02 ± 0.01^a

Within a column, means with different superscripts are significantly different (p < .05).

Table 2. Optical and granular characteristics of starch from seven yellow cassava cultivars.

Cultivar	Paste clarity (%)	Granule size (µm)		Shape description
		Range	Mean
S1	50.2 ± 0.1^a	6.0–19.1	11.0 ± 3.4	Spherical, oval, irregular, truncated,
S2	52.5 ± 0.1^b	6.3–12.4	9.0 ± 2.3	Spherical, irregular, truncated
S3	53.7 ± 0.3^c	7.6–15.4	8.5 ± 2.5	Oval, truncated, kettle drum
S4	55.6 ± 0.1^d	4.0–13.1	8.9 ± 3.1	Spherical, round, irregular, faceted
S5	49.4 ± 0.2^a	4.2–15.1	10.3 ± 3.1	Spherical, oval, truncated
S6	52.4 ± 0.2^b	6.5–15.2	8.6 ± 2.3	Spherical, oval, round, irregular, truncated
S7	50.2 ± 0.2^a	5.3–22.3	12.3 ± 3.6	Spherical, oval, irregular, kettle drum

Figure 1. SEM micrographs (×2500) of starch from seven yellow cassava cultivars.

Table 3. Physico-chemical properties of starch from seven yellow cassava cultivars.

Cultivar	AM (%)	SP (g/g)	SI (%)	Digestibility (%)	Crystallinity (%)	IR ratio 1047/1022
S1	15.6 ± 0.4^c	29.4 ± 0.2^c	15.7 ± 0.3^d	18.49 ± 0.63^e	35	0.73
S2	18.1 ± 0.2^e	28.1 ± 0.1^b	19.1 ± 0.3^e	11.42 ± 0.20^a	31	0.72
S3	15.9 ± 0.2^c	31.0 ± 0.1^d	15.0 ± 0.5 ^cd	13.26 ± 0.11^c	34	0.73
S4	13.6 ± 0.3^a	31.3 ± 0.4^d	14.2 ± 0.1^b	16.41 ± 0.18^d	37	0.76
S5	16.4 ± 0.1^d	27.3 ± 0.2^a	14.8 ± 0.4^c	13.22 ± 0.21^c	34	0.73
S6	14.5 ± 0.4^b	33.8 ± 0.2^e	13.0 ± 0.4^a	12.07 ± 0.17^b	36	0.75
S7	14.9 ± 0.2^b	29.7 ± 0.2^c	13.8 ± 0.3^a	11.52 ± 0.09^a	37	0.75

AM – amylose, SP –swelling power, SI – solubility index. Means with different superscripts are significantly different (p < .05).

Figure 2. WAXD diffractograms of starch from seven yellow cassava cultivars.

Figure 3. FTIR spectra of starch from seven yellow cassava cultivars.

Table 4. Pasting properties of starch from seven yellow cassava cultivars.

Cultivar	Ptime (min)	Ptemp (°C)	Peak viscosity (BU)	Trough viscosity (BU)	BD (BU)	BDR	SBR
S1	12.25	67.5^b	441^c	150 ^cd	291^b	0.340^d	1.38^a
S2	13.55	69.1^c	382^b	146^c	236^a	0.294^b	1.77^b
S3	11.45	66.2^a	520^d	154 ^cd	366^e	0.296^b	1.50^a
S4	12.17	66.5^a	462^c	100^a	365^e	0.216^a	1.73^b
S5	12.15	67.6^b	354^a	119^b	233^a	0.336^d	1.78^b
S6	11.42	65.9^a	510^d	160^d	350^d	0.314^c	1.51^a
S7	11.07	65.6^a	467^c	141^c	326^c	0.302^bc	1.91^c

P_time – pasting time (min); P_temp – pasting temperature (°C); BDR – breakdown Ratio; SBR – setback ratio

Table 5. Gel texture properties of starch from seven yellow cassava cultivars.

Cultivar	Firmness (N)	Consistency (N.s)	Adhesiveness (N)	Springiness	Cohesiveness
S1	3.36 ± 0.33^b	11.90 ± 0.21^b	0.83 ± 0.01^b	0.63 ± 0.10^ab	519.15 ± 0.5^a
S2	3.96 ± 0.08^c	11.92 ± 0.46^b	0.84 ± 0.01^b	0.69 ± 0.01^b	590.02 ± 4.3^b
S3	2.70 ± 0.27^a	8.60 ± 0.07^a	0.85 ± 0.02^bc	0.75 ± 0.01^bc	648.51 ± 1.5^c
S4	3.49 ± 0.09^b	12.75 ± 0.91^bc	0.84 ± 0.01^b	0.73 ± 0.01^b	644.54 ± 0.7^c
S5	3.40 ± 0.12^b	14.04 ± 0.11^c	0.87 ± 0.01^c	0.76 ± 0.01^c	838.71 ± 5.7^e
S6	3.77 ± 0.11^c	11.95 ± 0.91^b	0.83 ± 0.01^b	0.71 ± 0.01^b	751.25 ± 4.3^d
S7	3.89 ± 0.27^c	11.42 ± 0.64^b	0.79 ± 0.01^a	0.68 ± 0.01^b	579.91 ± 5.9^b

Figure 4. PCA biplot for physicochemical and functional properties of starch from seven yellow cassava cultivars.

AM – amylose, SI – water solubility index, SB – setback viscosity, BD – breakdown viscosity, PV – peak viscosity, Adh – adhesiveness, Cons – gel consistency, Firm – gel firmness MGS – mean granule size, Cryst – crystalinity, DG – digestibility, SP – swelling power.