Final SPH -JHS Coverpage 17-1 Jan 2022 single J. Hortl. Sci. Vol. 17(1) : 227-236, 2022 This is an open access article d istributed under the terms of Creative Commons Attribution-NonCommer cial-ShareAl ike 4.0 International License, which permits unrestricted non-commercial use, d istribution, and reproduction in any med ium, provide d the original author and source are credited. Original Research Paper INTRODUCTION Potato (Solanum tuberosum L.), the fourth most important vegetable crop, serves as an important raw source for starch extraction and applications in food industry. Potato starch can form thick visco-elastic gel unlike millet starches due to its composition of phosphate ester groups on amylopectin, larger granule size, longer amylose and amylopectin chain length, and higher purity (Singh et al.,2003). Its major application in food industry is limited by properties such as low shear resistance, thermal decomposition and thermal r esista nce, a nd its higher tendency towa r ds retr ogra da tion (Avula a nd Singh 2009). T hese limitations can be easily overcome by modification of extracted starch using extraction methods to meet the demands of final product (Liu et al.,2003). Changes in methods of extraction affect yield and recovery, cost, product pur ity, desir ed physico-chemica l properties, and mechanical properties of starch. Potato starch is unique compared to cereal starches (corn, wheat, rice, etc.) because of its wider granule size and purity, longer amylose and amylopectin chain length, presence of phosphate ester groups on amylopectin, ability to exchange certain cations with corresponding effects on viscosity behaviour, ability to form a thick viscoelastic gel upon heating and subsequent cooling in water, and poor thermal as well as shear stability of this gel (Singh et al., 2003). Pre-treatments such as curing have also been reported to affect yield and amylose content of starch. This investigation was thus performed out with an aim to characterize the morphological and physiochemical characteristics of potato starch extracted by control and combined method (extraction with ambient water 30oC + 0.25% NaOH + 2% w/v SDS: ME + 5.25% NaOCl + 0.15% cellulase enzyme) from fresh and cured tubers of five cultivars to identify varieties of potato with highest starch content so as to aid the farmers and industry. MATERIALS AND METHODS Plant material The fresh harvested potato tuber (Solanum tuberosum L.) of Kufri Chipsona-4 (V1), Kufri Badshah (V2), Kufri Pushkar (V3), Kufri Bahar (V4) (white flesh Morphological, physiochemical and colour characteristics of fresh and cured starch in potato varieties Neeraj1*, Siddiqui S.1,2, Dalal N.1, Bindu B.3 and Srivastva A.1,4 1Centre of Food Science and Technology, CCS Haryana Agricultural University, Hisar - 125 004, India 2School of Agricultural Sciences, Sharda University, Greater Noida - 201 310, U.P., India 3Department of Food Nutrition and Food Technology, Lady Irwin College, New Delhi, India 4 ICAR, Directorate of Mushroom Research, Solan, H.P., India *Corresponding author E-mail : phogatneeraj23@gmail.com ABSTRACT The present study was conducted to study the morphological, physicochemical and colour characteristics of potato starch extracted by control and combined methods from potato varieties viz., Kufri Chipsona-4, Badshah, Pushkar, Bahar and Sindhuri (fresh and cured). Among these varieties, Kufri Chipsona-4 exhibited maximum percent of small size (< 30 µm) particles (48%). Kufri Sindhuri showed highest starch purity (87.1%) but lowest whiteness (92.2%) whereas, highest whiteness (95.4%) was recorded in starch extracted from Kufri Badshah. Among starch extraction methods, combined method showed significantly lower starch moisture content (11.8%), fat (0.28%), protein (0.31%), ash (0.28%) and crude fibre (0.15%) whereas; starch purity (87.2%), percentage of small size particles (45%) and starch whiteness (96.3%) were observed higher than control methods in all varieties. Keywords: Curing, starch purity, starch whiteness and tuber 228 Neeraj et al J. Hortl. Sci. Vol. 17(1) : 227-236, 2022 varieties) and Kufri Sindhuri (V5) (pink flesh variety) were procured from Vegetable Farm, CCS Haryana Agricultural University, Hisar.They were sorted and cured without packaging in a BOD (Biological Oxygen Demand) incubator at ~22 oC temperature and 90% relative humidity in the dark for 18 days. Extraction of starch Fresh and cured potato tubers were used for starch extraction. For control extraction, starch was extracted a s descr ibed by Peshin (2001) with slight modifications. For combined extraction, a combined method of Phogat et al., (2020) (extraction with water at 30oC +0.25% NaOH + 2% w/v SDS:ME + 5.25% NaOCl + 0.15% cellulase enzyme) was used. The starch was analysed for the following parameters: Physico-chemical properties Potato starch was analysed for moisture, crude protein, fat, ash, and crude fibre content by the AOAC (2006) method. Starch yield (%) or crude starch content was calculated by the following formula: Starch purity (%) was calculated with the following formula: Purity (%) = [100 – (moisture + fatty materials+ crude protein+ ash + crude fibre)] Colour of starch: whiteness value [L* (whiteness or blackness), a* (redness or greenness) and b* (yellowness or blueness)] was measured by Hunter Lab Colorimeter (Colour flex, USA). Whiteness = 100 - [(100-L)2+ a2 + b2 ]1\2 Morphological properties The shape and size of extracted starch particles were ascertained using an inverted compound microscope (Olympus, Ja pa n; model: CX-41with 10× magnification) equipped with a digital camera. Starch particle size was measured using calibrated ocular scale fitted on the microscope lens. Statistical analysis The factorial CRD was used with three replications for analysis using OPStat software (Sheoran et al.,1998). Means were separated by critical difference (CD) at 5% significance level. Principal component analysis (PCA) was performed with PAST-3 software. RESULTS AND DISCUSSION Physico-chemical properties Va r ieties, cur ing a nd extr a ction methods ha d significant effect on physico-chemical properties of starch. Moisture content was varied from 11.7 to 12.6% (Table 1). Combined extraction method had lower starch moisture content.V5 had least (11.7%) starch moisture content and it was maximum (12.6%) in V2. The starch fat content ranged from 0.33 to 0. 43% (Ta ble 1). Combined tr ea tment ha s significa ntly lower fa t content. T her e was no significant difference in starch fat (%) extracted from 5 varieties, except V5 which exhibited significantly lower fat content (Table 3). The starch protein (%) of potato varieties ranged from 0.35 to 0.48% (Table 1). Combined treatment has significantly lower protein content. It was recorded minimum (0.35%) in V5 and maximum (0.48%) in V4 (Table 4). For all the varieties, there was nonsignificant effect of curing on starch moisture, fat and protein content (Table 2, 3 and 4). The starch ash content ranged from of 0.32 to 0.36% (Table 1). Variety and curing did not significantly affect ash content (Table 5). The starch crude fiber content ranged from 0.15 to 0.23% (Table 1). Combined tr ea tment extr a cted sta r ch ha d significa ntly lower a sh and crude fiber. It was minimum (0.15%) in V3 and it was maximum (0.23%) in V1 (Table 6). Curing had non-significant affect in crude fiber. The slight difference with respect to moisture content could be the result of extraction method, varieties, and curing (Table 2). Kim and co-workers (1995) reported differ ences r anging from 7.2-16. 70% in star ch moistur e contents a mong 42 pota to va r ieties. Karmakar et al., (2014) compared the moisture content of potato with taro and corn starch and pointed that starch moisture content also depends on the extent of drying. Similar was the observation by Abegunde et al., (2013). The lower fat (Table 3) and protein content (Table 4) in starch extracted by combined treatment attributed to the action of alkali and SDS used during extraction. NaOH, an alkali solvent, can easily solubilize major proteins enclosing the starch and thus soften-up the protein-starch matrix. Kaur and co-workers (2007) observed that the Kufri Sindhuri had highest ash content and Kufri Chandarmukhi the lowest. Starch purity The starch purity varied between 86.0 to 87.1% (Table 1). Variety and curing did not significantly affect the starch purity (Table 7). The starch purity for all the potato varieties was observed significantly higher 229 Starch morphological, physiochemical and colour characteristics Ta bl e 1. S um m ar y st at is tic s of s ta rc h ch ar ac te ri st ic s of p ot at o va ri et ie s. St ar ch c ha ra ct er is ti cs M in M ax S. D . Sk ew ne ss K ur to si s C oe ff . V ar M oi st ur e co nt en t (% ) 11 .7 0 12 .6 0 0. 34 -0 .2 8 -0 .0 9 2. 81 Fa t (% ) 0. 33 0. 43 0. 04 -1 .8 1 3. 25 10 .4 7 Pr ot ei n (% ) 0. 35 0. 48 0. 06 -0 .2 4 -2 .9 1 14 .4 9 A sh ( % ) 0. 32 0. 36 0. 01 0. 55 0. 87 4. 39 C ru de f ib re ( % ) 0. 15 0. 23 0. 03 0. 61 -0 .6 8 17 .4 4 Pu ri ty ( % ) 86 .0 0 87 .1 0 0. 45 0. 38 -1 .1 4 0. 52 W hi te ne ss ( % ) 92 .2 0 95 .4 0 1. 41 0. 45 -2 .5 9 1. 50 Sm al l si ze p ar tic le s (% ) 41 .0 0 48 .0 0 2. 86 0. 31 -1 .5 4 6. 48 Ta bl e 2. M oi st ur e co nt en t (% ) of s ta rc h as i nf lu en ce d by v ar ie tie s, c ur in g an d ex tr ac tio n m et ho ds . E xt ra ct io n m et ho ds C ur in g O ve ra ll V ar ie ti es C on tr ol m et ho d C om bi ne d tr ea tm en t m ea n F re sh C ur ed M ea n F re sh C ur ed M ea n F re sh C ur ed K uf ri C hi ps on a- 4 (V 1) 13 .4 ±0 .5 4 12 .2 ±0 .5 1 12 .8 10 .4 ±0 .4 7 12 .5 ±0 .6 4 11 .5 11 .9 12 .4 12 .1 K uf ri B ad sh ah ( V 2) 11 .7 ±0 .6 8 13 .3 ±0 .7 8 12 .5 11 .4 ±0 .4 1 13 .9 ±0 .7 6 12 .7 11 .6 13 .6 12 .6 K uf ri P us hk ar ( V 3) 12 .5 ±0 .8 8 11 .7 ±0 .7 4 12 .1 12 .7 ±0 .8 1 11 .4 ±0 .3 9 12 .0 12 .6 11 .6 12 .1 K uf ri B ah ar ( V 4) 13 .5 ±0 .7 1 12 .8 ±0 .6 4 13 .2 11 .7 ±0 .8 5 11 .7 ±0 .5 9 11 .7 12 .6 12 .3 12 .4 K uf ri S in dh ur i (V 5) 12 .5 ±0 .5 8 12 .4 ±0 .6 2 12 .5 11 .4 ±0 .6 1 10 .5 ±0 .6 0 11 .0 12 .0 11 .5 11 .7 M ea n 12 .6 11 .8 12 .1 12 .3 C D a t 5% V ar ie tie s (V ) = 0. 54 C ur in g (C ) = N S M et ho ds ( M ) = 0. 35 V ×M = 0 .7 8 V ×C = 0 .7 8 M ×C = N S V ×M ×C = 1 .1 1 M ea n± SD ; N S – no n- si gn if ic an t J. Hortl. Sci. Vol. 17(1) : 227-236, 2022 230 Ta bl e 3. F at c on te nt ( % ) of s ta rc h as i nf lu en ce d by v ar ie tie s, c ur in g an d ex tr ac tio n m et ho ds . E xt ra ct io n m et ho ds C ur in g O ve ra ll V ar ie ti es C on tr ol m et ho d C om bi ne d tr ea tm en t m ea n F re sh C ur ed M ea n F re sh C ur ed M ea n F re sh C ur ed K uf ri C hi ps on a- 4 (V 1) 0. 59 ±0 .1 5 0. 58 ±0 .1 1 0. 58 0. 28 ±0 .0 8 0. 24 ±0 .0 5 0. 26 0. 44 0. 41 0. 42 K uf ri B ad sh ah ( V 2) 0. 48 ±0 .0 6 0. 53 ±0 .0 3 0. 50 0. 22 ±0 .0 6 0. 36 ±0 .0 7 0. 29 0. 35 0. 44 0. 40 K uf ri P us hk ar ( V 3) 0. 47 ±0 .1 1 0. 60 ±0 .0 5 0. 53 0. 34 ±0 .0 9 0. 34 ±0 .0 8 0. 34 0. 40 0. 47 0. 43 K uf ri B ah ar ( V 4) 0. 56 ±0 .0 6 0. 57 ±0 .1 6 0. 56 0. 29 ±0 .0 4 0. 30 ±0 .0 9 0. 29 0. 43 0. 43 0. 43 K uf ri S in dh ur i (V 5) 0. 47 ±0 .0 5 0. 43 ±0 .0 9 0. 45 0. 17 ±0 .0 5 0. 25 ±0 .0 7 0. 21 0. 32 0. 34 0. 33 M ea n 0. 53 0. 28 0. 39 0. 42 C D a t 5% V ar ie tie s (V ) = 0. 07 C ur in g (C ) = N S M et ho ds ( M ) = 0. 04 V ×M = N S V ×C = N S M ×C = N S V ×M ×C = N S M ea n± SD ; N S – no n- si gn if ic an t Ta bl e 4. P ro te in c on te nt ( % ) of s ta rc h as i nf lu en ce d by v ar ie tie s, c ur in g an d ex tr ac tio n m et ho ds . E xt ra ct io n m et ho ds C ur in g O ve ra ll V ar ie ti es C on tr ol m et ho d C om bi ne d tr ea tm en t m ea n F re sh C ur ed M ea n F re sh C ur ed M ea n F re sh C ur ed K uf ri C hi ps on a- 4 (V 1) 0. 48 ±0 .0 8 0. 53 ±0 .0 8 0. 51 0. 34 ±0 .1 7 0. 38 ±0 .0 5 0. 36 0. 41 0. 46 0. 43 K uf ri B ad sh ah ( V 2) 0. 55 ±0 .1 5 0. 61 ±0 .1 1 0. 58 0. 35 ±0 .1 8 0. 36 ±0 .1 9 0. 35 0. 45 0. 48 0. 47 K uf ri P us hk ar ( V 3) 0. 46 ±0 .0 7 0. 41 ±0 .0 3 0. 44 0. 29 ±0 .0 9 0. 27 ±0 .0 4 0. 28 0. 37 0. 34 0. 36 K uf ri B ah ar ( V 4) 0. 70 ±0 .0 1 0. 67 ±0 .1 2 0. 68 0. 30 ±0 .0 6 0. 25 ±0 .1 3 0. 28 0. 50 0. 46 0. 48 K uf ri S in dh ur i (V 5) 0. 38 ±0 .0 6 0. 49 ±0 .0 5 0. 43 0. 28 ±0 .1 4 0. 26 ±0 .0 4 0. 27 0. 33 0. 37 0. 35 M ea n 0. 53 0. 31 0. 41 0. 43 C D a t 5% V ar ie tie s (V ) = 0. 09 C ur in g (C ) = N S M et ho ds ( M ) = 0. 06 V ×M = 0 .1 3 V ×C = N S M ×C = N S V ×M ×C = N S M ea n± SD ; N S – no n- si gn if ic an t Neeraj et al J. Hortl. Sci. Vol. 17(1) : 227-236, 2022 231 Ta bl e 5. A sh c on te nt ( % ) of s ta rc h as i nf lu en ce d by v ar ie tie s, c ur in g an d ex tr ac tio n m et ho ds . E xt ra ct io n m et ho ds C ur in g O ve ra ll V ar ie ti es C on tr ol m et ho d C om bi ne d tr ea tm en t m ea n F re sh C ur ed M ea n F re sh C ur ed M ea n F re sh C ur ed K uf ri C hi ps on a- 4 (V 1) 0. 32 ±0 .0 6 0. 37 ±0 .0 6 0. 35 0. 30 ±0 .0 5 0. 31 ±0 .0 5 0. 31 0. 31 0. 34 0. 33 K uf ri B ad sh ah ( V 2) 0. 39 ±0 .0 4 0. 41 ±0 .0 9 0. 40 0. 27 ±0 .0 4 0. 31 ±0 .0 2 0. 29 0. 33 0. 36 0. 34 K uf ri P us hk ar ( V 3) 0. 36 ±0 .0 5 0. 40 ±0 .0 5 0. 38 0. 31 ±0 .0 3 0. 21 ±0 .0 5 0. 26 0. 34 0. 30 0. 32 K uf ri B ah ar ( V 4) 0. 42 ±0 .0 3 0. 39 ±0 .0 6 0. 41 0. 26 ±0 .0 2 0. 28 ±0 .0 4 0. 27 0. 34 0. 33 0. 34 K uf ri S in dh ur i (V 5) 0. 36 ±0 .0 3 0. 47 ±0 .0 7 0. 42 0. 34 ±0 .0 6 0. 26 ±0 .0 3 0. 30 0. 35 0. 37 0. 36 M ea n 0. 39 0. 28 0. 33 0. 34 C D a t 5% V ar ie tie s (V ) = N S C ur in g (C ) = N S M et ho ds ( M ) = 0. 03 V ×M = N S V ×C = N S M ×C = 0 .0 4 V ×M ×C = 0 .0 8 M ea n± SD ; N S – no n- si gn if ic an t Ta bl e 6. C ru de f ib re c on te nt ( % ) of s ta rc h as in flu en ce d by v ar ie tie s, c ur in g an d ex tr ac tio n m et ho ds . E xt ra ct io n m et ho ds C ur in g O ve ra ll V ar ie ti es C on tr ol m et ho d C om bi ne d tr ea tm en t m ea n F re sh C ur ed M ea n F re sh C ur ed M ea n F re sh C ur ed K uf ri C hi ps on a- 4 (V 1) 0. 26 ±0 .0 9 0. 30 ±0 .0 8 0. 28 0. 15 ±0 .0 4 0. 20 ±0 .0 5 0. 17 0. 21 0. 25 0. 23 K uf ri B ad sh ah ( V 2) 0. 17 ±0 .0 3 0. 24 ±0 .0 6 0. 20 0. 16 ±0 .0 4 0. 22 ±0 .0 7 0. 19 0. 17 0. 23 0. 20 K uf ri P us hk ar ( V 3) 0. 19 ±0 .0 4 0. 15 ±0 .0 4 0. 17 0. 11 ±0 .0 4 0. 13 ±0 .0 4 0. 12 0. 15 0. 14 0. 15 K uf ri B ah ar ( V 4) 0. 28 ±0 .0 6 0. 16 ±0 .0 7 0. 22 0. 15 ±0 .0 7 0. 13 ±0 .0 6 0. 14 0. 21 0. 14 0. 18 K uf ri S in dh ur i (V 5) 0. 17 ±0 .0 5 0. 25 ±0 .0 9 0. 21 0. 10 ±0 .0 3 0. 11 ±0 .0 4 0. 11 0. 14 0. 18 0. 16 M ea n 0. 22 0. 15 0. 18 0. 18 C D a t 5% V ar ie tie s (V ) = 0. 04 C ur in g (C ) = N S M et ho ds ( M ) = 0. 03 V ×M = N S V ×C = 0 .0 6 M ×C = N S V ×M ×C = N S M ea n± SD ; N S – no n- si gn if ic an t Starch morphological, physiochemical and colour characteristics J. Hortl. Sci. Vol. 17(1) : 227-236, 2022 232 Ta bl e 7. P ur ity ( % ) of s ta rc h as i nf lu en ce d by v ar ie tie s, c ur in g an d ex tr ac tio n m et ho ds . E xt ra ct io n m et ho ds C ur in g O ve ra ll V ar ie ti es C on tr ol m et ho d C om bi ne d tr ea tm en t m ea n F re sh C ur ed M ea n F re sh C ur ed M ea n F re sh C ur ed K uf ri C hi ps on a- 4 (V 1) 85 .0 ±0 .9 8 86 .0 ±0 .9 5 85 .5 88 .5 ±0 .8 3 86 .4 ±0 .6 6 87 .4 86 .7 86 .2 86 .5 K uf ri B ad sh ah ( V 2) 86 .7 ±0 .4 1 84 .9 ±0 .7 4 85 .8 87 .5 ±0 .8 5 84 .9 ±0 .5 1 86 .2 87 .1 84 .9 86 .0 K uf ri P us hk ar ( V 3) 86 .0 ±0 .7 9 86 .7 ±0 .7 3 86 .4 86 .3 ±0 .3 9 87 .7 ±0 .8 2 87 .0 86 .2 87 .2 86 .7 K uf ri B ah ar ( V 4) 84 .5 ±0 .9 2 85 .4 ±0 .5 8 85 .0 87 .3 ±0 .8 0 87 .3 ±0 .5 5 87 .3 85 .9 86 .4 86 .1 K uf ri S in dh ur i (V 5) 86 .1 ±0 .7 7 85 .9 ±0 .6 9 86 .0 87 .7 ±0 .8 5 88 .6 ±0 .4 4 88 .1 86 .9 87 .2 87 .1 M ea n 85 .7 87 .2 86 .6 86 .4 C D a t 5% V ar ie tie s (V ) = N S C ur in g (C ) = N S M et ho ds ( M ) = 0. 38 V ×M = 0 .8 5 V ×C = 0 .8 5 M ×C = N S V ×M ×C = 1 .2 0 M ea n± SD ; N S – no n- si gn if ic an t (87.2%) when starch was extracted by combined treatment. Pure starch had lower protein, fat, and ash content. Thus, the non-significant differences observed in purity of starches from different varieties was due to the nonsignificant differences in fat and ash contents of their starches (Table 5 and 6). Abegunde and co- workers (2013) reported that starch purity was reasonably high (>91%) in sweet potato cultivars due to low starch impurities (moisture, fat, protein, ash, and crude fibre). In the present study starch purity was maximum in V1 because it had less impurities (Table 7). Combined extraction resulted in significantly lower crude fibre, fat, protein and ash contents of starch hence combined treatment had lower impurity content in starch and thus produced starch with higher purity. Starch paste thought to be clear and did not contain any off colouration, especially if it’s to be used in food application. Kordylas (1990) reported that impurities in form of moisture, fat, protein, ash and crude fibre content decrease the starch whiteness value. Principal component analysis (PCA) PCA wa s per for med keeping in mind the characteristics of starch among the potato varieties. The eigenvalue, variance contribution rate of PCs and the cumulative variance are presented in Table 10. The first three PCs with eigen values >1.0 accounted for 92.71 % of variation among potato varieties. Other PCs were not interpreted since they had eigen values <1.0.T he fir st PC, explained 56.56 % of total variation. Eigen vector of the first principal component had high loading values for starch moisture content (0.41), protein content (0.41), purity (-43) and whiteness (0.38). Second principal component which r epresented 21. 47 % of total var ia tion mainly represented the starch ash (0.56), fat (-44) content and starch small size particles (-0.53). Third principal component explained mainly crude fibre (0.64). The biplot between PC1 and PC2 (Fig 2) compares the potato varieties based on their starch characteristics. Starch whiteness Starch whiteness ranged from 92.2 to 95.4 (Table 1). Va r ieties, extr a ction methods a nd cur ing ha d significantly affected starch whiteness value. It was minimum (92.2) in V5 and it was maximum (95.4) in V2. For all the varieties, combined extraction method had significantly higher starch whiteness value and curing of potatoes resulted in significantly lower whiteness value of extra cted star ch (Table 8). Neeraj et al J. Hortl. Sci. Vol. 17(1) : 227-236, 2022 233 Combined method extracted starch had significantly higher starch whiteness because of bleaching action of chemicals or by decreased moisture content, protein, fat, ash, and crude fibre contents which act as impurity. Colour is an important criterion for starch quality, especially for use in various types of food products. Minimum whiteness value was recorded in starch extracted from Kufri Sindhuri (92.2) due to its pink flesh and maximum (95.4) in V2 (Table 8). Curing resulted in lower starch whiteness. Abegunde a nd co-worker s (2013) a lso repor ted differ ent whiteness values of starches extracted from varieties of sweet potato using multiple extraction methods to remove pigments from starch. This is in agreement with the reports of Hu and co-workers. (2011) who observed that starch colour isolated from two-day old root was slightly grey. Morphological properties The percentage of small size particles (< 30 µm) in different potato varieties ranged from 41% to 48%. Curing and method of extraction non significantly affected the percentage of small size particles. Minimum number of small size particles was observed in V2 (41%) and V5 (42%) and maximum in V1 (48%). In the present investigation, Minimum number of small size particles was observed in V2 (41%) and V5 (42%) and maximum in V1 (48%) (Table 9& Figure 1). Minimum number of small size particles was observed Fig. 2. Segregation of the potato varieties based on their respective starch traits as determined by PCA. in V2 (41%) and V5 (42%) and maximum in V1 (48%) (Table 9). This may be attributed to difference in temperature of the locations during tubers growth. Singh and Singh (2001) documented small and large sta r ch gr a nules of 15-20 µ m a nd 20-45 µ m respectively, with shapes r anging from oval to irregular or cuboidal, which may be attributed to difference in tubers growth. Further, it has also been r epor ted tha t sta r ch gr a nule size is dir ectly proportional to the weight of a potato tuber (Liu et al., 2003). During tuber development, the membranes and physical characteristics of plastids differ among potato varieties and this in turn lead to difference among shape of starch granules among varieties (Lindeboom et al., 2004). Physicochemical properties of starch had been linked to difference in its granule shape and size. Skewness and kurtosis Skewness and kurtosis were calculated to analyse the genetic difference among potato varieties. The positive skewness was obtained for starch small size particles, yield, ash content, crude fibre, purity and whiteness whereas negative skewness was found for starch moisture content, fat and protein. The starch fat and ash content showed platykurtic distribution (positive) pattern. Leptokurtic distribution (negative) was followed by starch small size particles, crude fibre, purity, whiteness, peak viscosity, moisture, and protein content (Table 1). Starch morphological, physiochemical and colour characteristics J. Hortl. Sci. Vol. 17(1) : 227-236, 2022 234 Ta bl e 8. C ol ou r va lu e (w hi te ne ss ) of s ta rc h as i nf lu en ce d by v ar ie tie s, c ur in g an d ex tr ac tio n m et ho ds . E xt ra ct io n m et ho ds C ur in g O ve ra ll V ar ie ti es C on tr ol m et ho d C om bi ne d tr ea tm en t m ea n F re sh C ur ed M ea n F re sh C ur ed M ea n F re sh C ur ed K uf ri C hi ps on a- 4 (V 1) 94 .4 ±0 .5 1 90 .9 ±0 .6 4 92 .6 97 .4 ±0 .6 7 97 .0 ±0 .8 6 97 .2 95 .9 93 .9 94 .9 K uf ri B ad sh ah ( V 2) 95 .8 ±0 .6 4 91 .1 ±0 .7 8 93 .5 97 .9 ±0 .5 3 96 .8 ±0 .5 1 97 .4 96 .9 94 .0 95 .4 K uf ri P us hk ar ( V 3) 90 .8 ±0 .8 7 88 .7 ±0 .7 7 89 .7 95 .3 ±0 .7 2 96 .0 ±0 .8 4 95 .7 93 .0 92 .4 92 .7 K uf ri B ah ar ( V 4) 91 .8 ±0 .8 4 90 .1 ±0 .4 9 91 .0 95 .2 ±0 .7 7 95 .4 ±0 .6 5 95 .3 93 .5 92 .8 93 .1 K uf ri S in dh ur i (V 5) 88 .6 ±0 .7 9 88 .2 ±0 .5 8 88 .4 95 .8 ±0 .6 0 96 .1 ±0 .6 1 95 .9 92 .2 92 .1 92 .2 M ea n 91 .0 96 .3 94 .3 93 .0 C D a t 5% V ar ie tie s (V ) = 0. 56 C ur in g (C ) = 0. 36 M et ho ds ( M ) = 0. 36 V ×M = 0 .8 0 V ×C = 0 .8 0 M ×C = 0 .5 0 V ×M ×C = N S M ea n± SD ; N S – no n- si gn if ic an t Ta bl e 9 Pe rc en t of s m al l s iz e (< 3 0 µm ) pa rt ic le s of s ta rc h as in flu en ce d by v ar ie tie s, c ur in g an d ex tr ac tio n m et ho ds . E xt ra ct io n m et ho ds C ur in g O ve ra ll V ar ie ti es C on tr ol m et ho d C om bi ne d tr ea tm en t m ea n F re sh C ur ed M ea n F re sh C ur ed M ea n F re sh C ur ed V 1 45 49 47 47 51 49 46 50 48 V 2 39 40 40 41 43 42 40 42 41 V 3 42 43 43 44 45 45 43 44 44 V 4 43 46 45 46 48 47 45 47 46 V 5 40 42 41 42 44 43 41 43 42 M ea n 43 45 43 45 C D a t 5% V ar ie tie s (V ) = 4 C ur in g (C ) = N S M et ho ds ( M ) = N S V ×M = 6 V ×C = 6 M ×C = 4 V ×M ×C = 6 M ea n± SD ; N S – no n- si gn if ic an t Neeraj et al J. Hortl. Sci. Vol. 17(1) : 227-236, 2022 235 Table 10. Principal component (PC) loadings for quality variables of the potato starch. Starch characteristics PC1 PC2 PC3 Moisture content (%) 0.41 0.20 -0.36 Fat (%) 0.36 -0.44 -0.25 Protein (%) 0.41 0.25 0.00 Ash (%) -0.24 0.56 0.23 Crude fiber (%) 0.33 0.09 0.64 Starch purity (%) -0.43 -0.20 0.23 Starch whiteness (%) 0.38 0.23 0.28 Small size particles (%) 0.18 -0.53 0.46 Eigen value 4.52 1.72 1.17 % Variance 56.56 21.47 14.67 Cumulative variance (%) 56.56 78.04 92.71 Fig. 1. Particle of starch from potato varieties as effected by curing (inverted compound microscope (Olympus, Japan; model: CX-41) equipped with digital camera facility at 10 x power lens.) In the present study, biplot indicates that starch crude fibr e, moistur e, pr otein a nd sta r ch whiteness correspond more to Kufri Badshah and Kufri Bahar whereas, starch fat (%), and small size particles values correspond more to Kufri Chipsona-4 (Fig. 2). The starch purity was more associated with the Kufri Sindhuri and Kufri Pushkar. The angle size between two or more traits in the biplot is directly proportional to correlation between those characters. A high positive correlation was discerned between the starch crude fibre, moisture, protein and starch whiteness value whereas, high negative correlation was discerned by starch purity with starch protein, moisture, crude fibre content, and starch whiteness. The biplot reflected diversity among potato varieties based on variables measured. Projection of the variables on the factors plane exhibits an independent group consisting of starch characteristics and the PCA analysis revealed several remarkable variations that exist among potato varieties. Kong et al., (2009) extracted four principal components (using 17 variables) that accounted for 88% of the total variance of starches properties, both physiochemical and functional, isolated from 15 amaranth grain cultivars. Starch morphological, physiochemical and colour characteristics J. Hortl. Sci. Vol. 17(1) : 227-236, 2022 236 CONCLUSION Characteristics of starch extracted varied with potato variety, curing and, extraction method. Least moisture and protein content and highest starch purity was observed in Kufri Sindhuri. Kufri Sindhuri also resulted in least starch fat content and starch colour values. The percentage of small size particles was maximum in Kufri Chipsona-4 and minimum in Kufri Badshah. Starch extracted by combined method had lower starch moisture content, fat, protein, ash and crude fibre and higher starch purity, percentage of small size particles, yield, and starch colour values. Curing resulted in lower starch yield, starch whiteness value, higher peak viscosity. It can be thus concluded that it is profitable to extract starch by combined method fr om fr esh tuber s of va r iety Kufr i Chipsona 4. ACKNOWLEDGEMENT This work was supported by the Centre of Food Science and Technology, CCS Haryana Agricultural University, Hisar, India under the student research work for Ph.D. REFERENCES A.O. A.C. (2006): Official Methods of Methods of An alysis. Associa tion of Offici al Anal ytical Chemists. Washington, D. C. Abegunde, O.K., Mu, T.H., Chen, J.W. and Deng, F.M, 2013. Physicochemical characterization of sweet potato starches popularly used in Chinese starch industry. Food hydrocolloids.33(2):169- 177. Avu l a , R. Y. a n d Si n gh , R. K , 2 00 9 . F un c t i on a l properties of potato flour and its role in product development-A review. Food.3:105-112. Hu, W., Jiang, A., Jin, L., Liu, C., Tian, M. and Wang, Y, 2011. Effect of heat treatment on quality, thermal and pasting properties of sweet potato starch during yearlong storage. Journal of the Science of Food and Agriculture.91:1499-1504. Ka r m a k a r, R. , Ba n , D. K . a n d Gh osh , U, 2 01 4. Com par a t i ve st udy of n a t ive a n d m odi fi ed s t a r c h e s i s ol a t e d fr om c on ve n t i on a l a n d nonconventional sources. International Food Research Journal.21: 597-602. Kaur, A., Singh, N., Ezekiel, R. and Guraya, H.S,2007. Physicochemical, thermal and pasting properties of sta rch es separ a ted from di fferent pot at o cultivars grown at different locations. Food Chemistry.101:643-651. Kim, Y.S., Wiesenborn, D.P., Orr, P.H. and Grant, L.A,1995. Screening potato starch for novel p r op e r t i e s u s i n g d i ffe r en t i a l s c a n n i n g calorimetry. Journal of Food Science.60:1060- 1065. Kong, X., Ba o, J. a n d Cor ke, H, 2009. Ph ysica l p r op e r t i e s of A m a r a n t h u s st a r c h . F o o d Chemistry.113:371-376. Kordylas, J.M, 1990. Processing and preservation of t ropical an d sub-tr opi cal foods, Macmi l la n Publishers, 414-426. Lindeboom, N., Chang, P.R. and Tyler, R.T, 2004. Analytical, biochemical and physicochemical aspects of starch granule size, with emphasis on small granule starches: a review. Starch.56:89-99. Liu, Q., Weber, E., Currie, V. and Yada, R, 2003. Physicochemical properties of starches during potato growth. Carbohydrates Polymer.51:213-221. Phogat, N., Siddiqui, S., Dalal, N., Srivastva, A. and Bindu, B, 2020. Effects of varieties, curing of tubers and extraction methods on functional characteristics of potato starch. Journal of Food Measurement and Characterization. 14:3434– 3444. Peshin, A, 2001. Characterization of starch isolated from potato tubers (Solanum tuberosum L.). Journal of food science technology.38:447-449. Sheoran, O.P., Tonk, D.S., Kaushik, L.S., Hasija, R.C. and Pannu, R.S. 1998. Statistical Software Package for Agricultural Research Workers. Recent Advances in information theory, Statistics & Computer A ppl i cat i ons by D. S. Hooda & R. C. Ha si ja Department of Mathematics Statistics, CCS HAU, Hisar, 139-143. Sin gh , J. a n d Si n gh , N, 2001. St udi es on th e morphological, thermal and rheological properties of starch separated from some Indian potato cultivars. Food Chemistry.75:67-77. Singh, N., Singh, J., Kaur, L., Sodhi, N.S. and Gill, B.S, 2003. Morphological, thermal and rheological properties of starches from different botanical sources. Food chemistry.81:219-231. Neeraj et al J. Hortl. Sci. Vol. 17(1) : 227-236, 2022 (Received: 16.01.2022; Revised: 17.02.2022; Accepted: 02.03.2022) 00 A Final SPH -JHS Coverpage First 2 pages.pdf 00 Content and in this issue.pdf 01 Mohan Kumar G N.pdf 02 Meera Pandey.pdf 03 Biradar C.pdf 04 Varalakshmi B.pdf 05 Vijayakumari N.pdf 06 Barik S.pdf 07 Sajid M B.pdf 08 Ranga D.pdf 09 Usha S.pdf 10 Manisha.pdf 11 Amulya R N.pdf 12 Akshatha H J.pdf 13 Adak T.pdf 14 Sujatha S.pdf 15 Gowda P P.pdf 16 Subba S.pdf 17 Dhayalan V.pdf 19 Ahmed S.pdf 20 Vishwakarma P K.pdf 21 Deep Lata.pdf 22 Udaykumar K P.pdf 23 Nayaka V S K.pdf 24 Sahel N A.pdf 25 Bayogan E R V.pdf 26 Rathinakumari A C.pdf 27 Yella Swami C.pdf 28 Saidulu Y.pdf 29 Sindhu S.pdf 30 Neeraj.pdf 31 Sivaranjani R.pdf 32 Rashied Tetteh.pdf 34 Sangeetha G.pdf 35 Shareefa M.pdf 36 Last Pages.pdf