|
Received: 12 April 2016
Revised: 3 August 2016
|
Accepted: 10 September 2016
DOI: 10.1111/jfpp.13217
ORIGINAL ARTICLE
Amaranth (Amaranthus spp.) starch isolation, characterization, and utilization in development of clear edible films Narender K. Chandla | Dharmesh C. Saxena Department of Food Engineering and Technology, Sant Longowal Institute of Engineering & Technology (SLIET) (Deemed University), Longowal, Sangrur, Punjab, India Correspondence Sukhcharn Singh, Department of Food Engineering and Technology, Sant Longowal Institute of Engineering & Technology (SLIET), Longowal, Sangrur, Punjab, India. Email:
[email protected]
|
Sukhcharn Singh
Abstract The aim of this study was to analyze the isolated starches for physico-chemical, structural, and morphological characteristics and to see amaranth starch efficacy in formation of edible films. All the amaranth cultivars have presented purity in range from 99.54 to 99.74% (db). Granules of starch were found small in size ranged from 1.182 to 1.431 mm (PSA). Granules of Amaranth starches showed tightly packed, angular, and polygonal shape (SEM). X-ray diffraction analysis indicating A type crystalline structure of isolated starches. AHA and AHD starches were found higher in crystalinity, swelling power, and water/oil binding capacity in comparison to AC and APR starches. All the starches were observed higher solubility, greater paste clarity, intermediate peak
Funding information Sant Longowal Institute of Engineering & Technology (SLIET) and Ministry of Human Resources Development (MHRD)
viscosity/temperature (RVA), and unique visco-elastic behavior. Isolated and characterized amaranth starches were tried for their application in development of edible films. During experimentation, amaranth starches were found suitable for formation of clear edible films of optimum properties viz. thickness, tensile strength, solubility, and water vapor permeation.
Practical applications Evaluation of properties of Amaranth starch provided information for its possible usage in food as coating material/edible film. In this study, Amaranth starch was studied and thereby analyzed and investigated with an aim to develop starch films. Amaranth starch based transparent clear edible films were prepared and found that these films made could help in elimination of excessive primary packaging and add more quality to whole food in one and other way. This incursion of Amaranth starch could be perceived as an affirmative consumer benefit in near future by maintaining the keeping quality of raw and processed foods held within up during transportation up to final consumption. KEYWORDS
Amaranth starches, edible films, morphology, physico-chemical properties
1 | INTRODUCTION
Amaranth grain is a valuable food source and contains high quality proteins, vitamins, minerals, and bioactive compounds other than
Amaranth is well-known due to its unique starch, high amylopectin
starch. The Amaranth grain have high protein content (12–18%), carbo-
content, and for high nutritional value. Amaranth starch is isolated
hydrate content (62–68%), oil content (8%) in comparison to most of
from
Amaranthaceae
the other cereal grains (Brenner, 2000; Silva-Sanchez, 2008). Amaranth
Amaranthus
spp.
belongs
to the
family
(Brenner, 2000) Amaranthaceae include 60 species wherein Amaran-
was originally cultivated in South and Latin America and many parts of
thus hypochondricus, Amaranthus caudatus, Amaranthus paniculates L.,
Himalayas. Adaptation trials and commercial production of this plant is
and Amaranthus cruentus are the species which are presumed as
currently being conducted in Ontario, Canada to meet the high con-
good as cereal grains in term of nutritional and chemical composi-
sumer demand. In India, Amaranth cultivation is under way and culti-
tion (Singh & Singh, 2011). Amaranth grain can resists drought,
vated in Himalayan foothills viz. Himachal Pradesh, Uttrakhand, Punjab,
heat, pests and have shown adaptation to new environmental
and in many parts of Maharashtra (Rana, Pradheep, Yadav, Verma, &
conditions.
Sharma, 2007; Singh & Singh, 2011).
J Food Process Preserv. 2017;41:e13217. https://doi.org/10.1111/jfpp.13217
wileyonlinelibrary.com/journal/jfpp
C 2017 Wiley Periodicals, Inc. V
|
1 of 11
2 of 11
|
Starch is a universal polysaccharide present in this grain Amaranth in abundance quantity. The demand of starch has increased enor-
CHANDLA
ET AL.
thickness, tensile strength, water vapor permeability, solubility, and transparency.
mously in recent years as starch is being used widely in production of biodegradable plastics, edible films and bio-ethanol, apart from its gen-
2 | MATERIALS AND METHODS
eral use in food processing industries. In general, food processing industries utilizes starch in production of dextrin, pasta, and gravies and many more (Ming et al., 2011; Mosab, Kotiba, & Fawaz, 2012). Although, corn, potato, wheat, and rice starches are the most commonly used in the food industry for the transformation of the functionality of the products. In food processing industries, starch contributes for a variety of characteristics that include thickening, thinning, gelling, and shelf stability in varied applications (Choi, Kim, & Shin, 2004; Wani et al., 2012, 2014). But a new pseudo cereal-starch like Amaranth starch has found its application in food and non-food (cosmetics, textile, paper coatings, and as laundry starch) applications, due to its func tional characteristics (Adina & Meireles, 2014; Singh & Singh, 2011). Amaranthus starch has diverse amylose content in between 4.7
2.1 | Material Amaranth cultivars were procured from different locations of India. Amaranthus Chaulai (AC) was procured from the local market of Sangrur, India. Amaranthus hypochondricus Anapurna (AHA) and Amaranthus hypochondricus Durga (AHD) were collected from National Bureau of Plant Genetic Resources (NBPGR), regional station, Phagli, India. Amaranthus paniculates Rajgeera (APR) was procured from local market of Nasik, Maharashtra, India. CMC (Carboxymethyl Cellulose) and AR grade glycerol were purchased from Merck Specialities Pvt. Ltd., India.
2.2 | Isolation of starch
and 12.5% and Kong, Van Villet, and Walstra (2009) reported that amy-
Amaranth seeds were manually cleaned, dried in oven at 408C for 48
lose content is an important factor which affects the functional proper-
hr and ground into flour using lab scale stone mill (Local make: Sangrur,
ties of starch and product made of this starch. Granules of Amaranthus
Punjab, India) and passed through 70 mesh sieve (British Standard
starch are smaller in comparison to the starch granules extracted from
Size). Starch was isolated by modified method of Choi et al. (2004).
other commercial cereals starches. Starches (Corn, Rice, & Amaranthus)
Alkali (NaOH) solution was prepared at 0.25% (wt/vol) concentration.
which has higher amylopectin content could lower down the gelatiniza-
The alkali solution to flour ratio was standardized to 1:5 and steeped at
tion temperature, enhance paste clarity, provide starch with stability
48C for 20 hr on the basis of preliminary experiments. Successive filtra-
against retrogradation, and allow it to withstand the repeated freeze-
tion was done with screens of sizes 100, 200, and 300 mesh size (BSS),
thaw processes (Kalita, Kaushik, & Mahanta, 2014). Due to functional
respectively. Filtrate/permeate collected after filtration was called as
and unique properties, this starch plays an important role in many tech-
milky starch obtained at first stage and retained residue on screens
nological textural interventions. Amaranthus starch have shown smaller
was collected back and wet-ground with fresh water (1:5) for 2.5 min
granular size, good gelatinization at lower temperatures and moderated
and filtration processes was reapplied and permeate (starchy milk) was
peak viscosity, elastic properties, and great paste clarity. These built-up rez, properties of this starch is appreciated in food industry (Bello-Pe Montealvo, & Acevedo, 2006; Bhandari & Singhal, 2007; Kong et al., 2009; Kong, Kasapis, Bertoft, & Corke, 2010; Lopez-Rubio, Flanagan, Gilbert, & Gidley, 2008; Pal, Singhal, & Kulkarni, 2001; Resio & Suarez, 2001; Singh et al., 2014). Paradigm shift imposed by the growing environmental awareness, motivate us to look for edible films and coating which could also be friendly with the environment and health of consumer. The polysaccharides used to form edible films are starch and starch derivatives, protein, cellulose and cellulose derivatives, gums, and pectinates. Edible films are primarily used to improve mechanical properties of foods, minimize the respiration rates of fruits and vegetables, limit the move-
collected at second stage. Now milk obtained at first and second stage were mixed together and centrifuged (Model-Eltek 4100 F; RCF3,0003g) for 15 min. The supernatant was discarded while protein layer was scraped off. The white residue remained after removal of protein was collected as white wet mass of starch. Wet starch was dried at 408C for 24 hr and then passed through 100 mesh size sieve for powder formation. Powdered starches were packed airtight and stored under refrigerated conditions until the analysis and formation of films.
2.3 | Physico-chemical properties of starch 2.3.1 | Color of starches Hunter colorimeter (Model i5 Green Macbeth, USA) was used for esti-
ment of moisture and gases and even used to enhance the sensory
mation of optical properties of starch from Amaranth cultivars. Data
properties of foods. In addition to above applications, our research has
was recorded as L*, a*, and b* values (L* 5 black to white; a* 5 green
advanced toward the development of clear edible films of desired
to red; and b* 5 blue to yellow).
properties. Thus, the research aimed to facilitate the customer with real image of product held within the package so to increase overall
2.3.2 | Amylose content
acceptability.
Starch samples of 70 mg were mixed with 10 ml of urea and DMSO
Therefore, objective of this study was to provide a complete char-
(Di-methyl-sulphoxide) solution in 1:9 ratio. The mixed solution was
acterization of Amaranth starches and then on the basis of presented
heated for 10 min with continuous stirring for proper mixing and incu-
properties of isolated starches, utility of these starches in formation of
bated at 1008C for 1 hr and then cooled to room temperature. Addition
edible films was tested. Developed edible films were evaluated for
of 0.5 ml mixed incubated sample solution was added to 25 ml of
CHANDLA
|
ET AL.
3 of 11
distilled water, along with 1 ml solution of Iodine (I) and potassium
to room temperature (Sandhu & Singh, 2007). Paste clarity was
Iodide (KI). This 1 ml solution was made by addition of 2 mg Iodine and
absorbed as percentage transmittance at 640 nm against water as
20 mg potassium Iodide and volume was made up to 1 ml by distilled
blank with UV-Spectrophotometer (ID 5000 HACH, USA).
water. Blank sample was also prepared without addition of starch sample and absorbance was taken at 635 nm (Morrison & Laignelet, 1983). Blue Valueð%Þ 5
Absorbance 3100 2 3 gm of solution 3 weight of sample
2.7 | Pasting properties (1) The pasting properties of the starch powder (3 g, 12.5% db) were
Amylose Content ð%Þ 5 28:4143Blue Value
determined by Rapid Visco Analyzer (RVA, Starch Master TM; Model: N17133; Newport Scientific Pvt. Ltd., Warriewood, Australia). The starch samples were programmed within RVA and hold at 508C for 1
2.4 | Swelling power and solubility
min, and then heated to 958C within 4 min, held at 958C for 3 min and
Swelling power (SP) and solubility of starches were performed by
then cooled to 508C within 3 min and hold at 508C for 2 min. From the
studying the methods of various authors (Adebooye & Singh, 2008;
curve, pasting temperature and viscosity profile was obtained.
Kong et al., 2009; Schoch, 1964; Wang & Wang, 2004), at 958C and latter a modified method was developed. The starch (1.0 g) suspension was heated in 25 ml of water with gentle stirring for first 15 min and
2.8 | Dynamic rheology
remaining 10 ml water was added thereafter. Briefly, a homogeneous
The moisture content of starch sample used for analysis was 10% db.
mixture of starch (1.0 g, dry basis) in distilled water (35 ml) was heated
The starch suspensions were prepared at 25% wt/wt basis with double
in 80 ml centrifuge tube at 958C for 30 min. Samples were then cooled
distilled water, magnetically stirred for 15 min and loaded on ram of
in ice bath for 1 hr and centrifuged (Model: C-24, BL; Remi Laboratory Ltd., Mumbai, India) at 12,500 rpm for 30 min. The suspended cloudy layer was poured through double folded cheese cloth by gravitation for 2 min and soluble matter which passes on the cheese cloth (filtrate) was considered as supernatants while gel retained on filter cloth was collected back inside the tube as sediments. The weight of sediment was recorded for SP and supernatant collected was poured in previously weighted petri dish and dried in oven at 1008C for 3.5 hr and weighted for the solubility determination. The swelling power (SP, g/g, dry basis) and solubility (S, %) were calculated as below: Mass of dried solids 3100 Weight of starch taken Sediment weight ðwet massÞ Swelling power ðg=gÞ5 Sample weight of starch taken
Solubility ð%Þ5
(2) (3)
Rheometer. The starch sample was covered along the circumference of the ram by silicone oil to minimize the losses due to evaporation during heating process applied for the gelation. The storage modulus and loss modulus of starch suspensions were analyzed using Rheoplus-Model; 300MR, (Austria), using parallel plate probe pp50. The strain, gap between probe, ram, and frequency were set to 1%, 1 mm, and 1.0 rad/s, respectively. The starch samples were heated from 40 to 908C at a rate of 28C/min and effect of heating on visco-elastic properties; storage modulus (Gʹ) and loss modulus (G00 ) was studied. The dynamic rheology parameters were determined in term of temperature ramp and its effect on visco-elastic behavior of starch suspension on heating.
2.9 | Thermal properties The Differential Scanning Colorimetery (Model: DSC 821e; Mettler Tol-
2.5 | Water/oil binding capacity (WBC/OBC)
edo, Switzerland) was calibrated with indium and data was analyzed by
Water and oil binding capacities were determined by method described by Medcalf and Gilles (1965). 5 g starch was taken and dissolved in
Star SW 9.01 software program. Two milligrams (dry basis) of starch was placed in an aluminum pan and moisture level adjusted to 70% by
75 ml distilled water and oil for water and oil binding capacity, respec-
double de-ionized water and pan was hermetically sealed and equili-
tively. The sample was agitated for 1 hr and centrifuged at 3,000 rpm
brates for 1 hr at 48C. The calorimeter was heated from 40 to 1208C at
for 10 min. the free water and oil recovered from the sentimental
a rate of 108C/min. In analysis, on set (To), peak (Tp), and conclusion
starch sample was removed and tubes were drained for 10 min to sep-
(Tc) were measured and recorded (Sandhu & Singh, 2007).
arate out the surface water and oil. The water/oil binding capacity was calculated as follows: Weight of sendiments WBC=OBC ð%Þ5 3100 Weight of sample
2.10 | FTIR–ATR analysis (4)
FTIR Spectrophotometer (Model: Cary 600 series, Agilent Technology, California, USA), equipped with attenuated total reflectance (ATR) was
2.6 | Paste clarity
used for the analysis. The FTIR spectrum was recorded using IRspectra of Amaranth starches in the 4,000–800 cm1 wavelength range
Paste clarity of the starch was estimated by UV-spectrophotometer.
with automatic signal scan of 16 scans with a resolution range of
The starch suspensions (1%) were prepared in distilled water and
2 cm21. Each spectrum was baseline corrected and reflectance was
heated in boiling water bath for 1 hr with constant stirring and cooled
normalized between 0 and 1 as a 100% transmittance.
4 of 11
|
CHANDLA
ET AL.
with an accuracy of 61 mm. The average value of 10 thickness meas-
2.11 | X-ray Diffraction Analysis Starch samples were analyzed for crystalinity by using an X-ray diffractometer, PAN analytical, Phillips, Holland, Model No. X’Pert’ PRO with the following conditions: target Cu-anode X-ray, 30 KV, 40 mA and scanning speed of 0.58/min. The diffractograms were analyzed in an
urements at different locations on each film sample was used in all calculations.
2.16 | Moisture content
angle of 2Ɵ in a range of 5 to 408. The crystalinity peaks were calcu-
Moisture content (MC) of the Amaranth starch films was determined
lated according to Lopez-Rubio et al. (2008). The crystalline structure
using standard methods of analysis of the AOAC (1995). Pieces of each
and degree of crystalinity were calculated as follows:
(1.0 g) were dried in an oven at 1208C, for approximate for 6 hr and
Degree of crystalinity 5 Ac =ðAc 1Aa Þ:ðAc 1Aa Þ
(5)
till the weight comes constant. The reported results represent the average of three samples in each case. The percentage of MC was calcu-
Where; Ac is the total area of crystalline peaks and Aa is the amorphous
lated as follow:
area on the diffractograms (Hayakawa, Tanaka, Nakamura, Endo, &
MC ð%Þ5
Hoshino, 1997).
2.12 | Particle size distribution (PSD)
Mw2Md 3100 Md
(6)
Where; Mw is the mass of the wet sample and Md is the mass of the dried sample.
Laser diffraction particle size analyzer, Shimadzu SALD-2300 was used to determine the partial structural characteristics (particle size distribu-
2.17 | Tensile strength
tion) in term of percentage volume of the equivalent spheres. The starch samples were dispersed in cuvette and fixed to the sample port
Tensile strength (TS) was determined using a texture analyzer, Model:
of equipment which measure in range of 17 nm to 2,500 mm. The
TA.XT2i, SMS, Surrey, England. Films were cut into 20 mm wide and
starch sample was added to sample port drop-wise till the obscuration to 40%.
50 mm long strips, and mounted between the grips of the texture analyzer. The initial grip separation was set at 30 mm and speed at 1.0 mm/s. TS (force/initial cross sectional area was determined directly
2.13 | Scanning electron microscopy (SEM) The samples were mounted on aluminum stub using a double backed cellophane tape, coated in auto fine coater, Model: JEOL-JFC-1600,
from the stress 3 strain curves using the software Texture Expert.
2.18 | Solubility
with gold palladium (60:40, wt/wt). All the starch samples were ana-
Films solubility in water was determined according to the method pro-
lyzed by scanning electron microscope (SEM), Model No. JSM 6610-LV
posed by Romero-Bastida et al. (2005). Concisely, 20 mm 3 20 mm
JEOL, Tokyo, Japan. The granule shape as a major morphological char-
dried films samples were weighted. Dry weight of the samples was
acteristic of the sample was absorbed at moisture content of 5–6%.
obtained by drying them at 1058C for 24 hr in an oven (Macro Scien-
The starch samples were examined at magnifications of 5,000 and
tific Works [MAC] Pvt. Ltd., New Delhi, India). After the first weighing,
10,000 X.
the samples were immersed in a flask containing 80 mL of distilled water, at 208 for 1 hr. The swollen samples were then removed and
2.14 | Film formation
dried again at 1058C for 24 hr before determining their final dry weight. Reduction in weight is taken as percentage loss in weight in 1
Filmogenic solutions were obtained by dispersion of Amaranth starch,
hr.
10.0 g per 100 ml in double distilled water for 10 min. with continuous stirring. Films were prepared by the method of Valderrama Solano and
2.19 | Water vapor permeation
Rojas de Gante (2014). Glycerol (2.5 g/100 g starch), used as plasticizer, was added and the resulting dispersion was then magnetically stirred
Water vapor permeability of the films was determined at room temper-
for 20 min at 808C (Tp-DSC). The film-forming solution was then
~an Rojo, ature using a modified ASTM E96-00 procedure (Fama, Gan
allowed to cool at room temperature to prevent the air bubbles during
Bernal, & Goyanes, 2012). Samples were placed into air tight glass jars
pouring. Films were prepared by using the casting technique. Prepared
containing CaCl2, and then located in desiccators at RH of 70% and
film-forming solution was poured onto silicon coated (manually applied)
room temperature. Water vapor migration was determined from the
Teflon round tray (10 cm diameter). Films were dried for 16 hr at 508C
weight gain of the permeation, measuring over 24 hr for 7 days. WVP
in an oven with forced circulation.
were calculated as:
2.15 | Film thickness The thickness of the films was determined with a manual micrometer (Model: Mitutoyo 2046F, Mitutoyo Corporation, Kanagawa, Japan)
WVP5
WVM 3e Po 3RH
(7)
Where; e is the films thickness and Po the saturation vapor pressure of water at room temperature.
|
b*
ID 5000 HACH, USA). Films were cut into 15 mm wide and 50 mm long strips, and mounted between the cuvette of spectrophotometer
3.50 6 0.06ac
Transparency was determined using a UV-spectrophotometer (Model:
3.47 6 0.06bc
2.20 | Light transmittance
3.17 6 0.06d
ET AL.
3.53 6 0.06ab
CHANDLA
22.50 6 0.06d
a
22.83 6 0.06
a*
The mean value and standard deviation were reported for the statisti-
22.70 6 0.07ab
2.21 | Statistical evaluation
22.57 6 0.06
c
and transparency value were recorded at 600 nm at 258C.
was observed among AC, AHA, AHC, and APR, respectively. The varia-
95.20 6 0.06d
97.13 6 0.06
ab c
92.23 6 0.32b
respectively. Significant variation (p < .05) in the yield of the starches
88.60 6 0.26
AHA, AHD, and APR were in range from 31.47 to 38.0 g/100 g,
84.87 6 0.64d
Paste clarity (%)
The starch yield obtained by alkali wet-grinding treatment for AC,
91.70 6 0.98
a
3 | RESULTS AND DISCUSSION
L
Optical value
by Mini Tab Statistica 7. (Statesoft Inc., OK, USA).
96.03 6 0.06
c
jected to one way analysis of variance (ANOVA), followed by Duncan’s
97.23 6 0.06a
cal analysis. All the analysis were determined in the triplicates and sub-
by Villarreal, Ribotta, and Iturriaga (2012) for alkali extracted Amaranth
bc
193.40 6 2.03b
95.20 to 97.13, which is in accordance with (L*) value (96.64) reported
185.67 6 3.40
to 99.74 g/100 g. Amaranthus starches color value (L*) varied from
236.02 6 0.45a
Oil binding capacity (%)
starch isolation. Purity of the starches was found in range from 99.54
170.33 6 0.76
cd
tion might be due to difference among Amaranth cultivars used for
Results are expressed as mean value 6 standard deviation of three determinations. Means in column with different superscript differ significantly (p < .05).
198.41 6.78a 54.60 6 0.20a 8.10 6 0.1d
199.47 6 0.76
199.23 6 0.35ac
a
d
179.60 6 0.92 36.47 6 0.06
c
2.81 6 0.01c
within.
APR
of Amaranthus composed of amylopectin which hold the water and oil
35.60 6 0.30
starch granule (Leach, McCowen, & Schoch, 1959). The starch granule
10.29 6 0.08
absorb water and the degree of association of water molecules within
3.43 6 0.02
in Table 1. Water binding capacity of starch granule is the tendency to
AHD
Water and oil binding capacity of Amaranth starches were in range from 179.60 to 200.41% and 170.33 to 236.02%, respectively, shown
38.50 6 0.10b
responsible for the observed differences in SP and solubility.
9.76 6 0.0b
small size of the starch granules and relative amylose content is
a
ules (Kaur, Singh, Ezekiel, & Guraya, 2007). Our study suggests that the
3.13 6 0.03b
in the amylose and associative bonding forces within the starch gran-
AHA
observed in APR. Variation in SP could be attributed to the variations
8.40 6 0.05
Starches of AHD showed the highest SP, while the lowest was
1.87 6 0.03
SP of Amaranth starches cultivars ranged from 8.10 to 10.29 g/g whereas solubility varied from 35.60 to 54.60% shown in Table 1.
AC
and in formation of films.
c
ranth starch including gelatinization, SP, peak viscosity, and crystalinity
d
content affects the physico-chemical and functional properties of Ama-
Solubility (%)/(908C)
0 to 7.8%. Our results are in agreement with these authors. Amylose
Swelling power (g/g)/(908C)
that average amylose content in A. hypochondricus was in a range from
T AB LE 1
Stone and Lorentz (1984) and Wu, Yue, Sun, and Corke (1995) found
Functional properties of starches isolated from Amaranth cultivars
various authors (Choi et al. 2004; Hoover, Sinnott, & Perera, 1998).
Amylose content (%)
in range of early reported value for different Amaranthus genotypes by
Amaranthus Cultivars
Water binding capacity (%)
Amylose content of Amaranthus starches was shown in Table 1. The reported values are in range from 1.87 to 3.43% which were found
bc
purity of starches.
abc
starches. However, no significant difference was observed in case of
5 of 11
6 of 11
|
CHANDLA
ET AL.
F I G U R E 1 (a) RVA curve of starches isolated from Amaranth cultivars. PV 5 peak viscosity; FV 5 final viscosity; PT 5 pasting temperature (8C). (b) Visco-elastic curves of AHD starch isolated from Amaranth cultivars
The paste clarity (%, T) of the starches was found in range from 84.87 to 91.80% shown in Table 1. Starches of AHD showed the highest paste clarity, while the lowest was observed in AHA. Higher paste clarity is further positively co-related with color and transparency value of the product formed from these starches.
3.2 | Dynamic rheology During the heating and cooling period starch of AC, AHA, AHD, and APR suspensions Gʹ and G00 have shown changes with respect of heating of starch suspensions and cooling of the gelatinized starch (Figure 1b). In both the cases, starch paste at 25% wt/wt has shown viscoelastic behavior with increase in the temperature, and storage modulus increased to maxima and still tent to increase further with increase in
3.1 | Pasting properties Pasting properties provide information about cooking behavior of starches at different temperatures. Viscosity of all starches was found to be increase within specified temperature range. Pasting profile of different cultivars varied due to difference in amylose content as reported by Wu and Corke (1999). Peak viscosity is regarded as maximum viscosity gained by starch granule to swell itself before physical rupture. AHA was found highest final viscosity (FV), followed by AHD due to higher amylose content within Amaranth starches. Highest peak
heating as high temperature is required for amylopectin for gelation purpose (Keetles, Van Villet, & Walstra, 1996). The storage modulus (Gʹ) and loss modulus (G00 ) increases linearly during heating up to 908C and this phenomena has been ascribed up to gelation of solubilized amylose (Biliaderis & Zawistowski, 1990). Rate of loss modulus (G00 ) have been increased to lesser rate than the storage modulus (Gʹ) which may be due to immediate gelification of starch.
3.3 | Thermal properties
viscosity (PV) was observed in APR, followed by, AHD, AHA, and AC
Thermal properties of alkali treated Amaranth starch were recorded by
shown in Figure 1a. PV and FV of Amaranth starches were observed in
differential scanning colorimetery (Figure 2). Transition temperatures
range from 1,087 to 1,898 cp and 980 to 1,461 cp, respectively. Break
(To, Tp, and Tc) and enthalpy of gelatinization (DH (J/g)) are presented
down (BD) viscosity is expected to co-relate with the amylose content
in the Table 2. Amaranth Starches have shown the peak temperature
of starches (Abdel-Aal, Hucl, Chibbar, Han, & Demeke, 2002). The past-
(TP) in range of 72.418C to 74.318C and enthalpy of gelatinization (DH)
ing temperature (PT) of starches alkali isolated varies in a range of
was seen lowest for AHD and highest for APR. The starches with
75.17 to 76.748C. The pasting profiles of different cultivars varied from
higher crystalinity and particle granules sizes have shown higher onset,
those reported in Kong et al. (2009) and Singh et al. (2014).
peak, and conclusion temperature which may be due to reason that
FIGURE 2
DSC thermogrames spectrum of starches isolated from Amaranth cultivars
CHANDLA
T AB LE 2
|
ET AL.
7 of 11
Thermal properties of starches from Amaranth cultivars Thermal transition properties
Amaranthus cultivars Parameter
To (8C)
AC
68.80 6 0.06
AHA
68.89 6 0.01a
72.30 6 0.15cd
AHD
66.70 6 0.05
72.41 6 0.15
APR
68.70 6 0.10bc
Tp (8C) ab
d
74.31 6 0.06
DH (J/g)
Tc (8C) a
c
73.54 6 0.40b
84.56 6 0.05
R (8C) d
15.76 6 0.25a
78.90 6 0.02d
13.29 6 0.03b
9.18 6 0.20d
79.23 6 0.07
11.68 6 0.01
11.53 6 0.15bc
17.96 6 0.00a
11.94 6 0.40b
a
c
80.64 6 0.30b
10.76 6 0.09
c
Results are expressed as mean value 6 standard deviation of three determinations. Means in column with different superscript differ significantly (p < .05). Where; To: Onset temperature of the melting, Tp: Peak temperature of melting, Tc: Conclusion temperature of melting and DH: Enthalpy of gelatinization, R: (Tc–To).
more heat required in breaking the bonds and further melting of particle for gelation due to higher crystalinity value of Amaranth starches. Crystalinity increases with escalation in amylopectin content. For this reason value of transition temperature are in close conformity with the annotation of thermal value observed by Singh et al. (2014).
3.5 | X-ray diffractometric pattern X-ray diffraction has been used to reveal the presence and characteristics of crystal starch and crystal region (Singh, McCarthy, & Singh, 2006). X-ray diffraction of Amaranth starches presented in Figure 3a are similar diffractograms and displayed “A” type pattern which is similar to that cereal starches (Corn & Rice) with strong peaks intensity at 2Ø about 15, 17, 17.5, and 23.5 which is comparable with the finding
3.4 | FTIR–ATR analysis The FTIR spectrums of the Amaranth starches found same with no shift. Spectrum exhibit bands due to vibration modes offered by amylose and amylopectin thus have observed peaks around 1,145,
of Manek et al. (2005). Degree of crystalinity was found in range of 22.6 to 33.88%. Degree of crystalinity increase with increase in amylopectin content (Lopez-Rubio et al., 2008).
1,239.84, 1,239, 1,185 cm21 for AC, AHA, AHD, and APR, respectively.
3.6 | Particle size distribution (PSD)
These bands ascribed to the C–O stretch of C–O–C in starch, and
Average diameter (size) of starch granules from Amaranth starches iso-
mainly attributed to C–O stretch of C–O–H in starch. The wide band
lated ranges in between 1.182 and 1.431 mm. AC starch has shown
observed at 3,592, 3,552, and 3,581 cm21 can be attributed to the O–
minimum diameter ranges in between 0.664 and 0.819 mm as shown in
H stretching of alcohols and phenols in free form. The sharp bands at
Figure 4. Our results are in accordance with the morphological data by
2,883, 2,886, 2,887, and 2,875 cm21 may be attributed to the asym-
found SEM (Granular surface examination assessed at specific site for
metric stretching of C–H (alkane), while the band at 1,651, 1,652,
particle size could vary, but data bring into consideration is being
1,647, and 1,661 cm21, respectively, was ascribed to much adsorbed
within the starch particle size limits of minimum and maximum data
water (Yadav, Mahadevamma, Tharanathan, & Ramteke, 2007). The
which is an average of all diameter ranging from lower to higher,
ascribed band had shown that the starch is solvent (polar and non-
recorded during PSD analysis). Particle size of granule affects the
polar) loving and could be better utilized where higher water/oil bind-
physico-chemical and other functional properties likewise pasting vis-
ing capacities required.
cosity and of starch gelation temperature. Due to small size of granule
FIGURE 3
(a) X-ray diffraction pattern of starches isolated from Amaranth cultivars. (b) Amaranth starch translucent films
8 of 11
|
FIGURE 4
CHANDLA
ET AL.
Overlay particle size distribution graphs of starches isolated Amaranth cultivars
the starch could be used with other material to improve on the
tightly packed natively in starchy perisperm. The micrographs revealed
strength as filler material.
that Amaranth starch granules are polygonal and angular in shape and have varying starch granules size as shown in Figure 5. The size and
3.7 | Surface morphology by SEM
shape of granules are in close agreement with Villarreal et al. (2012). The micrographs have also revealed that the granules have aggregated
Scan Electron Microscopy (SEM) have played important role in under-
like grape bunch, tightly packed structure without any hollowness. The
standing the structure of the Amaranth starch. Morphological images
average diameter ranged from 0.221 to 2.351 mm within all Amaranth
of starch revealed cluster formation due to aggregation of granules
starches according to particle size analysis.
FIGURE 5
Surface morphology of starches isolated from Amaranth cultivars
CHANDLA
|
ET AL.
T AB LE 3
9 of 11
Amaranth starch based films functional properties Starch films functional properties
Parameter Amaranth cultivars
Moisture Content (%)
Thickness (mm)
Tensile Strength (MPa)
Solubility (%)
Transparency (%)
WVP (g/ms Pa) 310210
AC
19.8 6 0.20
0.28 6 0.02
2.31 6 0.01
37.56 6 0.10
96.76 6 0.01
d
2.76 6 0.05b
AHA
18.0 6 0.12c
0.29 6 0.01c
2.30 6 0.10c
34.90 6 0.20c
97.29 6 0.01c
2.18 6 0.11c
AHD
20.5 6 0.22
0.30 6 0.04
2.61 6 0.12
35.23 6 0.20
98.68 6 0.01
a
2.03 6 0.10d
APR
16.0 6 0.20d
0.32 6 0.02a
2.54 6 0.21ab
97.96 6 0.02b
2.94 6 0.05a
b
d
a
b
cd
a
a
b
33.64 6 0.01d
Results are expressed as mean value 6 standard deviation of three determinations. Means in column with different superscript differ significantly (p < .05). WVP 5 Water Vapor Permeability.
3.8 | Functional properties of films
3.11 | Light transmittance
3.8.1 | MC and thickness of films
Transparency of the films is an essential characteristic since it has a
Translucent films from Amaranth starches have been developed as
great influence on customer. Due to application of edible films on
shown in Figure 3b. The MC, thickness, TS, solubility, water vapor per-
fruits/vegetables and cheese/paneer the transparency is highly encour-
meability and transparency values of the prepared starch films are
aged to give real/actual appearance (Lopez-Rubio et al., 2008). There-
shown in Table 3. Uniformity in film thickness and MC is significant for
fore, transparency of developed films is highly desirable. The
attaining good repeatability of the mechanical properties of the films
transparency of starch films was observed excellent and this ranged
(Nascimento, Calado, & Carvalho, 2012). The values of thickness and
from 97.29 to 98.68% shown in Table 3.
moisture ranged from 0.28 to 0.32 mm and 16.0 to 20.5% for Amaranth starch films which is in range with other authors. According to
4 | CONCLUSIONS
Valderrama Solano and Rojas de Gante (2014) MC values of starch films should range from 16.50 to 34.39%.
Starch isolated was found better in comparison to other cereal structure in terms of purity, color, solubility, oil/water winding, and functional properties. A significant difference among starch yield has been
3.8.2 | Tensile strength
observed due to the variation in Amaranth cultivars. Amaranthus starch
According to Tapia-Blacido, do Amaral Sobral, and Menegalli (2013), TS
shown smaller granular sizes and lesser amylose content while high
values of starch films should range from 1.9 to 4.8 MPa, to achieve
value were found for water binding, oil binding, SP, solubility, amylo-
enough mechanical strength and subsequently impart other character-
pectin content, and crystalinity. Higher paste clarity of starch could be
istics (solubility, WVP) to films. During our study, the TS values of Ama-
better co-related with low amylose content of starch. Furthermore, X-
ranth starch films observed in range from 2.30 to 2.61 MPa.
ray diffraction, SEM analysis, and particle analysis revealed that the granules were polygonal, angular, and tightly packed structure. Evaluation of properties of Amaranth starch provided information for the development food and non-food products. In this study, the
3.9 | Solubility Solubility is an important character of films as lower solubility could result lower rate of degradation while higher solubility result collapse of material/pack within short time. Solubility values ranged from 33.64
outcome of this study was taken in development of clear edible films as a result of lower amylose content. Amaranth starch edible films made could eliminate excessive primary packaging and add more quality to food product in one or another way. This insertion of Amaranth
to 37.56% per hour which is an optimal range for edible films prepared
starch in other composite material for film preparation could be per-
from starch and its derivatives (Lopez-Rubio et al., 2008).
ceived as an affirmative consumer benefit, in near future.
ACK NOWLE DGME NT S
3.10 | Water vapor permeability
First author is grateful to Sant Longowal Institute of Engineering &
The major application of film is to barrier against moisture (in/out), pre-
Technology (SLIET) and Ministry of Human Resources Development
vent deteriorative reaction and prevent shrinkage due to water loss
(MHRD) for providing financial assistance through University Fellow-
Lopez-Rubio et al. (2008). WVP values of prepared starch films ranged
ship. With deep gratitude, I express my sincere thanks to National
210
(Tapia-Blacido et al., 2013) which
Bureau for Plant and Genetic Resources (NBPGR), New Delhi for
in turn advocate the potential of these films against moisture. The
providing me Amaranth seeds through Material Transfer Agreement
results showed that films made have minimum water vapor permeation
(MTA), analytical support sought from Sophisticated Analytical
to MC.
Instruments Laboratories (SAIL), Thapar University, Patiala and Indian
from 2.03 to 2.94(g/ms Pa) 3 10
10 of 11
|
CHANDLA
Institute of Technology (IIT) Rupnagar, PB, India. Above all, I am thankful to “The Almighty” for showering his blessings to complete this research.
ET AL.
Kong, X., Kasapis, S., Bertoft, E., & Corke, H. (2010). Rheological properties of starches from grain amaranth and their relationship to starch structure. Starch/Stärke, 62, 302–308. Leach, H. W., McCowen, L. D., & Schoch, T. J. (1959). Structure of the starch granule. I. Swelling and solubility patterns of various starches. Cereal Chemistry, 36, 534–544.
OR CID Dharmesh C. Saxena Sukhcharn Singh
http://orcid.org/0000-0002-2921-6724
http://orcid.org/0000-0003-3790-9683
R E FER E NCE S Abdel-Aal, E. S. M., Hucl, P., Chibbar, R. N., Han, H. L., & Demeke, T. (2002). Physicochemical and structural characteristics of flour and starches from waxy and non-waxy wheat. Cereal Chemistry, 79, 458–464.
Lopez-Rubio, A., Flanagan, B. M., Gilbert, E. P., & Gidley, M. J. (2008). A novel approach for calculating starch crystallinity and its correlation with double helix content: A combined XRD and NMR study. Biopolymers, 89, 761–768. Manek, R. V., Kunnle, O. O., Emeje, M. O., Builders, P., Rao, R. G. V, & Lopez, G. P. (2005). Physical, thermal and sorption profiles of starch obtained from Tacca leontopetaloildes. Starch/Stärke, 57, 55–61. Medcalf, D. G., & Gilles, K. A. (1965). Wheat starches. I. Comparison of physico-chemical properties. Cereal Chemistry, 42, 558–568.
Adebooye, O. C., & Singh, V. (2008). Physico-chemical properties of the flours and starches of two cowpea varieties (Vignaunguicu-lata (L.) Walp). Innovative Food Science and Emerging Technologies, 9, 92–100.
Ming, L., Peng, L., Wei, Z., Long, Y., Fengwei, X., & Huaying, P. (2011). Extrusion processing and characterization of edible starch films with different amylase contents. Journal of Food Engineering, 106, 95–101.
Adina, L. S., & Meireles, M. A. A. (2014). New starches are the trend for industry applications: A review. Food and Public Health, 4, 229–224.
Morrison, W. R., & Laignelet, B. (1983). An improved colorimetric procedure for determination of apparent and total amylose in cereal and other starches. Journal of Cereal Science, 1, 9–20.
AOAC. (1995). Official methods of analysis (15th ed.). Washington, D. C., USA: Association of Official Analytical Chemists. New York, USA. rez, L. A., Montealvo, M. G. M., & Acevedo, E. A. (2006). Bello-Pe Almidon: Definicíon, estructura y propriedades (in Spanish). In F. M. Lajolo & E. W. Menezes (Eds.), Carbohidratos en alimentos regionals iberoamericanos (pp. 19–46). S~ao Paulo, Brazil: EDUSP. Bhandari, P. N., & Singhal, R. S. (2007). Effect of succinylation on the corn and amaranth starch pastes. Carbohydrate Polymers, 48, 223–240. Biliaderis, C. G., & Zawistowski, J. (1990). Viscoelastic behavior of aging starch gels: Effect of concentration, temperature and starch hydrolysates on network properties. Cereal Chemistry, 67, 240–246. Brenner, D. M. (2000). Genetic resources and breeding of Amaranthus. Plant Breeding Reviews, 19, 227–285. Choi, H., Kim, W., & Shin, M. (2004). Properties of Korean amaranth starch compared to waxy millet and waxy sorghum starches. Starch/ Stärke, 56, 469–477. ~an Rojo, P., Bernal, C., & Goyanes, S. (2012). Biodegradable Fama, L., Gan starch based nanocomposites with low water vapor permeability and high storage modulus. Carbohydrate Polymers, 87, 1989–1993. Hayakawa, K., Tanaka, K., Nakamura, T., Endo, S., & Hoshino, T. (1997). Quality characteristics of waxy hexaploid wheat (Triticum aestivum L.): Properties of starch gelatinization and retrogradation. Cereal Chemistry, 74, 576–580. Hoover, R., Sinnott, A. W., & Perera, C. (1998). Physiochemical characterization of starches from Amaranthus cruentus grains. Starch/Stärke, 50, 456–463. Kalita, D., Kaushik, N., & Mahanta, C. L. (2014). Physicochemical, morphological, thermal and IR spectral changes in the properties of waxy rice starch modified with vinyl acetate. Journal of Food Science and Technology, 51, 2790–2796. Kaur, A., Singh, N., Ezekiel, R., & Guraya, S. H. (2007). Physicochemical, thermal and pasting properties of starches separated from potato cultivars grown at different locations. Food Chemistry, 101, 643–651. Keetles, C. J., Van Villet, A. M. T., & Walstra, P. (1996). Gelation and retrogradation of concentrated starch system: 1. Gelation. Food Hydrocollides, 10, 343–353. Kong, X., Van Villet, A. M. T., & Walstra, P. (2009). Physical properties of Amaranthus starches. Food Chemistry, 113, 371–376.
Mosab, K., Kotiba, H., & Fawaz, D. (2012). Thermoplastic starch blend: A review of recent works. Polymer Science Series A, 54, 165–176. Nascimento, T. A., Calado, V., & Carvalho, C. W. P. (2012). Development and characterization of flexible film based on starch and passion fruit meso-carpflour with nanoparticles. Food Research International, 49, 588–595. Pal, J., Singhal, R. S., & Kulkarni, P. R. (2001). Physicochemical properties of hydroxypropyl derivative from corn and amaranth starch. Carbohydrate Polymers, 48, 19–53. Rana, J. C., Pradheep, K., Yadav, S. K., Verma, V. D., & Sharma, P. C. (2007). Durga: A new variety of grain amaranth for cultivation in hill regions. Indian Farming, 57, 27–28. Resio, A. C., & Suarez, C. (2001). Gelatinization kinetics of amaranth starch. International Journal of Food Science and Technology, 36, 441–448. Romero-Bastida, C. A., Bello-Perez, L. A., Garcia, M. A., Martino, M. N., Solorza-Feria, J., & Zaritzky, N. E. (2005). Physico-chemical and microstructural characterization of films prepared thermal and cold gelatinization from non-conventional sources of starches. Carbohydrate Polymer, 60, 235–244. Sandhu, K. S., & Singh, N. (2007). Some properties of corn starches II. Physicochemical, gelatinization, retrogradation, pasting and gel textural properties. Food Chemistry, 101, 1499–1507. Schoch, T. J. (1964). Swelling power and solubility of granular starches. In R. L. Whistler (Ed.), Methods in carbohydrate chemistry. New York: Academic Press. Silva-S anchez, C. (2008). Bioactive peptides in Amaranth (Amaranthus hypochondriacus) seed. Journal of Agricultural and Food Chemistry, 56, 1233–1240. Singh, J., McCarthy, O., & Singh, H. (2006). Physio-chemical and morphological characteristics of New Zealand Taewa (Maori potato) starches. Carbohydrate Polymers, 64, 569–581. Singh, N., Kaur, S., Kaur, A., Isono, N., Ichihashi, Y., Noda, T., & Rana, J. C. (2014). Structural, thermal and rheological properties of Amaranthus hypochondricus and Amaranthus caudatus starches. Starch/Stärke, 66, 457–467. Singh, N., & Singh, P. (2011). Amaranth: Potential source for flour enrichment. In V. Preedy, R. Watson, & V. Patel (Eds.), Flour and breads and their fortification in health and disease (pp. 101–111). London: Academic Press.
CHANDLA
|
ET AL.
Stone, L. A., & Lorenz, K. (1984). The starch of Amaranthus-physicochemical properties and functional characteristics. Starch/Stärke, 36, 232–237. Tapia-Blacido, D., do Amaral Sobral, P. J., & Menegalli, F. C. (2013). Effect of drying conditions and plasticizer type on some physical and mechanical properties of amaranth flour films. LWT – Food Science and Technology, 50, 392–400. Valderrama Solano, A. C., & Rojas de Gante, C. (2014). Development of biodegradable films based on blue corn flour with potential applications in food packaging. Effects of plasticizers on mechanical, thermal, and microstructural properties of flour films. Journal of Cereal Science, 60, 60–66. Villarreal, M. E., Ribotta, P. D., & Iturriaga, L. B. (2012). Comparing methods for extracting Amaranthus starch and the properties of the isolated starches. LWT – Food Science and Technology, 51, 441–447.
11 of 11
Wani, I. A., Jabeen, M., Geelani, H., Masoodi, F. A., Saba, I., & Muzaffar, S. (2014). Effect of gamma irradiation on physicochemical properties of Indian Horse Chestnut (Aesculusindica Colebr.) starch. Food Hydrocolloids, 35, 253–263. Wu, H., & Corke, H. (1999). Genetic diversity in physical properties of starch from a world collection of Amaranthus. Cereal Chemistry, 76, 877–883. Wu, H., Yue, S., Sun, H., & Corke, H. (1995). Physical properties of starch from two genotypes of Amaranthus cruentus of agricultural significance in China. Starch/Stärke, 47, 295–297. Yadav, R. A., Mahadevamma, S., Tharanathan, R. N., & Ramteke, R. S. (2007). Characteristics of acetylated and enzyme modified potato and sweet potato flours. Food Chemistry, 103, 1119–1126.
Wang, L., & Wang, Y. J. (2004). Rice starch isolation by neutral protease and high intensity ultrasound. Journal of Cereal Science, 39, 291–296.
How to cite this article: Chandla NK, Saxena DC, Singh S.
Wani, A. A., Singh, P., Shah, M. A., Schweiggert-Weisz, U., Gul, K., & Wani, I. A. (2012). Rice starch diversity: Effects on structural, morphological, thermal and physicochemical properties. A review. Comprehensive Reviews in Food Science and Food Safety, 11, 417–436.
utilization in development of clear edible films. J Food Process Pre-
Amaranth (Amaranthus spp.) starch isolation, characterization, and serv. 2017;41:e13217. https://doi.org/10.1111/jfpp.13217
