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Improving the nutritive characteristics of corn flakes enriched with functional components

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  • Institute of General and Physical Chemistry University of Belgrade

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This paper investigates the effects of simultaneous addition of sunflower (3, 6 or 9 g/100 g of sample) and dry residue of wild oregano (0.5 or 1 g/100 g of sample) on the essential amino acids pattern and antioxidant potential of flake products. The accepted experimental design plan was 34. Data point that Score and PDCAAS values in flake products increase with increasing share of sunflower. Maximum value of phenolic compounds and antioxidant activity were experienced of TPC 2.84 mg/g, DPPH 0.75 mg/ml, FRAP 1.57 mg/g with the product having maximum shares of sunflower and dry residue of wild oregano. Tukey’s HSD test showed statistically significant differences between most of the mean values of amino acids content and antioxidant activity in the observed corn flakes. The response surface method has been applied for evaluation of amino acid content and antioxidative potential of corn flakes. Sunflower in flake products positively contributed to the protein nutritive value and dry residues of wild oregano elevated antioxidant potential of flake products and also contributed to the food waste valorisation in the food industry. Corn flakes are new products with improved essential amino acid pattern, antioxidant activity and functional properties due to added dry residue of wild oregano and sunflower. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. III 46005 and Grant no. TR 31027]
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495
Improving the nutritive characteristics of corn flakes enriched with
functional components
Milenko B. Košutić1, Lato L. Pezo2, Jelena S. Filipović1, Vladimir S. Filipović3
1Institute for Food Technology in Novi Sad, Novi Sad, Serbia
2Institute of General and Physical Chemistry, University of Belgrade, Beograd, Serbia
3Faculty of Technology, University of Novi Sad, Novi Sad, Serbia
A
bstract
This paper investigates the effects of simultaneous addition of sunflower (3, 6 or 9 g/100 g
of sample) and dry residue of wild oregano (0.5 or 1 g/100 g of sample) on the essential
amino acids pattern and antioxidant potential of flake products. The accepted experi-
mental design plan was 3×4. Data point that Score and PDCAAS values in flake products
increase with increasing share of sunflower. Maximum value of phenolic compounds and
antioxidant activity were experienced of TPC 2.84 mg/g, DPPH 0.75 mg/ml, FRAP 1.57
mg/g with the product having maximum shares of sunflower and dry residue of wild ore-
gano. Tukey’s HSD test showed statistically significant differences between most of the
mean values of amino acids content and antioxidant activity in the observed corn flakes.
The response surface method has been applied for evaluation of amino acid content and
antioxidative potential of corn flakes. Sunflower in flake products positively contributed to
the protein nutritive value and dry residues of wild oregano elevated antioxidant potential
of flake products and also contributed to the food waste valorisation in the food industry.
Corn flakes are new products with improved essential amino acid pattern, antioxidant
activity and functional properties due to added dry residue of wild oregano and sunflower.
Keywords: amino acid, antioxidant potential, wild oregano, sunflower, corn flakes.
SCIENTIFIC PAPER
UDC 641.1:664.6:635.7
Hem. Ind. 71 (6) 495–502 (2017)
Available online at the Journal website: http://www.ache.org.rs/HI/
Food wastes are today considered as a cheap
source of valuable components since the existent tech-
nologies allow the recovery of target compounds and
their recycling inside food chain as functional additives
in different products [1]. Waste valorisation practices
have attracted a significant amount of attention in
recent years with the aim of managing waste in the
most sustainable way [2,3]. Large quantities of waste
material are generated annually from agricultural acti-
vities and processing of agricultural products. Waste
can contain many reusable substances of high value [4].
Depending on the technology this residual matter can
be converted into commercial products either as raw
material for secondary processes, as operating supplies
or as ingredients of new products [5] like residue after
distillation of oil from wild oregano which is the natural
source of antioxidants [6].
Food consumption is primarily determined by
energy expenditure, a function of basal metabolic rate
and physical activity level. However, basal metabolic
rate, and consequently protein, varies with age, sex
and body weight. Physical activity varies with a lifestyle
Correspondence: M.B. Košutić, Institute for Food Technology in Novi
Sad, Bul. cara Lazara 1, 21000 Novi Sad, Serbia.
E-mail: milenko.kosutic@fins.uns.ac.rs
Paper received: 25 May, 2016
Paper accepted: 21 August, 2017
https://doi.org/10.2298/HEMIND160525012K
and patterns of behavior. Thus, when enough food is
eaten to satisfy energy needs, the needs for protein or
any other nutrient will also be satisfied if the ratio of
protein or other nutrients to energy is appropriate [7].
Ingredients that could be included in flakes formulation
are sunflower and wild oregano, which may significantly
improve nutritive and antioxidant properties [8–11].
The differences between fabricated samples were
tested using Tukey’s HSD test. The response surface
methodology (RSM) has been proven as useful method
for determining the influence of process variables on a
group of dependent parameters that are significant for
the process and effects studies [12]. RSM is an effective
tool for optimizing a variety of processes, especially in
design of mixture experiments [13]. The RSM equations
describe the effects of the test variables on the obs-
erved responses, determine test variables interrelation-
ships and represent the combine effect of all test vari-
ables in the observed responses, enabling the efficient
investigation of the process [12,13].
In this study the effect of varying the proportion of
sunflower (3, 6 and 9 g) and wild oregano dry residue
(0.5 and 1 g/100 g of sample) on the amino acid con-
tent and antioxidant potential of corn flakes was stu-
died with the aim to obtain new products with imp-
roved nutritional and functional properties.
M.B. KOŠUTIĆ et al.: NUTRITIVE CHARACTERISTICS OF CORN FLAKES Hem. ind. 71 (6) 495–502 (2017)
496
EXPERIMENTAL
Material
Corn flour used in this study was obtained from the
mill Žitoprodukt d.o.o., Bačka Palanka, Serbia, pro-
duced in 2014 with the following characteristics: mois-
ture content of 13.3%, sugar, protein, cellulose, starch
and lipid content (% dry matter basis) of 0.87, 5.59,
0.98, 79.43, and 1.57, respectively (AOAC 1990) [15].
Sunflower variety „Cepko“ was produced in 2014 by
„Vitastil“, Erdevik, Serbia, with following characteristics
of samples: protein, starch, lipid and cellulose, content
of 26.67, 6.73, 54.05 and 8.21 (% dry matter basis),
respectively (AOAC 1990) [15]. Sunflower was dehulled
and milled in a Hammer mill 2300 rev/min with 2.5 mm
sieve. Wild oregano (Origanum minutiflorum O. Schwarz
& P.H. Davis) harvest 2013, was produced by Inan tarim
ECODAB – Antalia, Turkey. Wild oregano (Origanum
minutiflorum), harvest 2013, was supplied by Inan
tarim ECODAB – Antalia, Turkey.
Methods
Preparation of dry residue of wild oregano
Dry residue from wild oregano was prepared as fol-
lows: the distillation of wild oregano was carried out in
the production plant of the Institute of Medicinal Plant
Research “Dr Josif Pančić” from Pančevo, Serbia. A mini
distiller based on water vapor principle was used for
distillation. The duration of the distillation time was 2.5
h. The waste in the process of distillation (trope) is
naturally cooled and dried by air flow in place, pro-
tected from sun and prepared for further research:
milled at a facility Repro Trade Ltd., on the hammer mill
Sever, Subotica (2300 rpm, sieve hole diameter 1.5
mm, particle size < 12 mm).
Preparation of corn flakes
Extrusion of flakes. The corn flakes was obtained by
extrusion in a twin-screw extruder (Yunnan Daily
Extrusion, Yunnan, China) in industrial conditions on
the factory Repro Trade Ltd., Industrial Zone bb,
Temerin, Serbia. Extrusion parameters were as follows:
the length of the screw 140 cm, diameter 3 mm×6 mm,
rotor speed of 180 rpm, temperature profile: 131/125/
/114 °C. The moisture of raw material mixture prior
extrusion was adjusted to 22%. Corn flour, was replaced
by milled sunflower in the quantity 3, 6 or 9 g/100 g of
sample, and dry residue of wild oregano added in the
quantity of 0.5 or 1 g/100 g of sample based on corn
flour and milled sunflower. Table 1 describes corn flour
formulation enriched with different quantities of milled
sunflower and dry residue of wild oregano. Obtained
extrudates were dried in the drying unit at temperature
of 84 °C, cooled for 30 min at controlled temperature
25±1 °C and stored at 4 °C in sealed plastic bags until
required for analysis.
Amino acids
The samples were prepared for analyses using the
24 h hydrolysis with 6 M HCl. Samples were analyzed
on a liquid chromatograph Agilent 7890A GC system
with a flame ionization detector FID-equipped auto-
matic sampler (autosampler) and silica capillary column
(SP-2560, 100 m×0.25 mm, ID, 0.20 μm). Amino acid
peaks were identified by comparing the retention time
of the individual amino acids in the sample with reten-
tion times of standards Amino Acid Standard (Sigma–
Aldrich), as well as the internal data of the library
data. The results are expressed in % as a proportion of
the individual amino acids in the total amino acids.
Antioxidant activity
Antioxidant activity was determined in samples of
wild oregano (WO), dry residue of wild oregano (DR),
Table 1. Corn flakes formulation with different quantities of milled sunflower and dry wild residue oregano
Sample
Corn flakes composition
Quantity of corn
g/100 g sample
Quantity of sunflower, g
replacing 100 g flour
Quantity of dry residue of wild oregano
g/100 g of sample
CF 1 100 0 0
CF 2 97 3 0
CF 3 94 6 0
CF 4 91 9 0
CF 5 100 0 0.5
CF 6 97 3 0.5
CF 7 94 6 0.5
CF 8 91 9 0.5
CF 9 100 0 1
CF 10 97 3 1
CF 11 94 6 1
CF 12 91 9 1
M.B. KOŠUTIĆ et al.: NUTRITIVE CHARACTERISTICS OF CORN FLAKES Hem. ind. 71 (6) 495–502 (2017)
497
sunflower (SF) and corn flakes (CF 1–12). The material
was grinded and extracts were obtained by subjecting 1 g
(WO, DR, SF) and 2 g (CF 1–12) of powdered material to
maceration in 100 ml 80% ethanol (in water) for 24 h at
ambient temperature in the dark. The extracts were fil-
tered using filter paper (Whatman No. 1) followed by
centrifugation (U-320 R, Boeco, Germany) at 4750g (4
°C) for 15 min and kept refrigerated. These extracts
were used for determination of total phenolic content
(TPC), DPPH antiradical power and ferric reducing anti-
oxidant power (FRAP). In all of the assays absorbances
were measured using Thermo Scientific Evolution 220
spectrophotometer. Total phenolic content (TPC) was
determined using a modification of the Foline–Ciocal-
teu method and the results expressed as mg of gallic
acid equivalents (GAE) per g of extract sample [16]. The
assay mixture contained 1 ml of Folin–Ciocalteu-phenol
reagent (previously diluted 1:10 with distilled water)
and 200 µl of the sample solution. The mixture was
neutralized with 7.5% sodium carbonate solution after
10 min. For each sample three replicates were carried
out and also a control (blank), where 1 ml of distilled
H2O was added instead of FC reagent. The absorbance
was determined after 60 min at 760 nm.
DPPH free radical scavenging activity was evaluated
according to the method of Sánchez [17] with minor
modifications. The assay procedure was the following:
15.7 mg of 2,2-diphenyl-1-picrylhydrazyl (DPPH) was
weighed and dissolved in absolute ethanol. A working
solution of 90 μM DPPH was prepared diluting 22 ml of
the primary DPPH solution to a volume of 100 ml in
methanol. The assay mixture contained 2 ml working
solution and different volumes of the sample solution.
In the control, the exact amount of the extract was
substituted with solvent (80% ethanol), and in the blank,
only methanol and extract were mixed. The mixture
was shaken vigorously on a Vortex mixer, then incub-
ated 60 min at 25 °C in a water bath in the dark, after
which the absorbance of the remaining DPPH was det-
ermined at 515 nm. For each sample three replicates
were carried out. Radical percentage of inhibition of
DPPH radical was calculated by the following equation:
I = 100(A0A1)/A0) (1)
Where A0 is the control and A1 is the sample sol-
ution absorbance. The concentration of extract that
inhibits the DPPH radical formation by 50% is defined
as IC50 (mg/ml). Finally, results were expressed as DPPH
antiradical power (DPPH ARP) defined as:
DPPH ARP = 1/IC50 (2)
Total antioxidant capacity was estimated according
to the FRAP assay [18]. The reduction potential of ext-
racts was calculated using the calibration curve of the
standard solution of ascorbic acid (R2 = 0.99). The work-
ing FRAP reagent was prepared by mixing acetate buf-
fer (300 mM, pH 3.6), 2,4,6-tripyridyltriazine reagent
(10 mM in 40 mM HCl) and FeCl36H20 (20 mM) in the
ratio of 10:1:1. The assay mixture contained sample
and 2 ml of working FRAP reagent and absorbance (593
nm) was measured after 6 min incubation in the dark at
room temperature. Due to the coloration of the ext-
racts, it was necessary to prepare a control (sample and
dH2O instead of the FRAP reagent) and blank (FRAP
reagent and 80 % ethanol instead of the sample). All
the samples were made in triplicate and mean values
of reducing power were expressed as mg of ascorbic
acid equivalents (AAE) per g of sample extract, calcul-
ated according to the standard calibration curve.
Protein quality evaluation
Nutritional value of proteins expressed by the fol-
lowing indicators: the amino acid score determines the
effectiveness with which absorbed dietary nitrogen can
meet the indispensable amino acid requirement at the
safe level of protein intake. This is achieved by a com-
parison of the content of the limiting amino acid (lys-
ine) in the protein or diet with its content in the
requirement pattern:amino acid score = mg of amino
acid in 1 g test protein / mg of amino acid in require-
ment pattern.
Following data were used for digestibility (FAO/
/WHO/UNU, 2002) [7]:
corn, 85%
sunflower, 90%
corn flakes with 3% of sunflower 85×0.97 +
90×0.03 = 85.15
corn flakes with 6% sunflower 85×0.94 +
90×0.06 = 85.30
corn flakes with 9% ssunflower 85×0.91 +
90×0.09 = 85.45
Statistical analyses
Descriptive statistical analyses for all the obtained
technological parameters were expressed as the mean
± standard deviation (SD). The evaluation of analysis of
variance (ANOVA) and principal component analysis
(PCA) analyses of the obtained results were performed
using StatSoft Statistica 10.0® software. Collected data
were subjected to ANOVA for the comparison of means,
and significant differences are calculated according to
post-hoc Tukey’s HSD (honestly significant differences)
test at p < 0.05 significance level, 95% confidence limit.
The experimental data used for the study of expe-
rimental results were obtained using a 3×4 experimen-
tal design, with 12 runs (1 block).
The following second order polynomial (SOP) model
was fitted into the data. The eleven models of the fol-
lowing form were developed to relate the five res-
ponses (Y) and two process variables (X):
M.B. KOŠUTIĆ et al.: NUTRITIVE CHARACTERISTICS OF CORN FLAKES Hem. ind. 71 (6) 495–502 (2017)
498
22
2
kk0 k k k122
11
ii iii i
ii
YXXXX
ββ ββ
==
=+ + +
 k1 = –11 (3)
where:
β
k0,
β
ki,
β
kii,
β
k12, are constant regression coef-
ficients; Yk is either essential amino acids (Lys, Thr, Val,
Ile, Leu, Met, Phe and His), phenolic compounds or
antioxidant activity values (TPC, DPPH* and FRAP); X1
oregano content and X2 – sunflower content.
RESULTS AND DISCUSSION
Correct evaluation of protein in food products
requires prediction of overall efficiency of protein util-
ization. According to FAO/WHO/UNU [7] measure of
overall efficiency of protein quality should determine
the capacity of food protein to meet metabolic demand
for essential amino acids. As metabolic needs for amino
acids and proteins depend on their part in biochemical
pathways. The essential amino acids of corn flakes
(CF1–12) with sunflower and wild oregano are pre-
sented in table 2. Addition of sunflower 6 and 9 g in
corn flakes (CF3 and CF4; CF7 and CF8; CF11 and CF12)
contributed to statistical significant increase in lysine.
The addition of sunflower (3, 6 or 9 g) contributes to a
statistically significant higher values of threonine,
methionine and histidine content in comparision with
samples without sunflower addition (CF1, CF5 and CF9).
Amino acids of sunflower contributed to statistically
insignificant decrease in leucine content and statisti-
cally significant decrease in isoleucine content of corn
flakes with added sunflower.
Table 3 shows the ANOVA calculations of the pre-
diction model for amino acid products with corn flakes
containing sunflower and wild oregano. It can be seen
that the SOP model used to calculate Lys content is
mostly influenced by the linear term of sunflower con-
tent, statistically significant at p < 0.01 level and the
linear term of oregano content, p < 0.05. The greatest
impact in the SOP models for Val, Ile, Met and Phe
calculation is observed by the linear member of sun-
flower content (p < 0.05).
The average error between the predicted values
and experimental values (calculated by Eq. (1)) was
below 10%. To verify the significance of the models,
ANOVA was conducted and the results indicate that all
models were significant with minor lack of fit, suggest-
ing that they adequately represented the relationship
between responses and factors.
Nutritional value was determined, based on the
amount and composition of protein and essential
amino acids. Score amino acid indicates the efficiency
of protein utilization in food and presents the ratio of
essential amino acid content in the tested protein and
the specific categories of consumers needs. The lowest
value score defined limiting amino acid.
The nutritive value of flake protein, expressed as
amino acid score, is presented in Table 4. Score det-
ermines the effectiveness by which the absorbed diet-
ary nitrogen can meet the essential amino acid require-
ment at a safe level of protein intake. WHO/FAO/UNU
[7] marked lysine, sulfur amino acids, threonine and
tryptophan as the most deficient aminoacids in food
proteins. The results of the investigation show that
lysine is the limiting amino acids in all corn flakes (CF1–
12). All the values are less than 1, and addition of
sunflower increased the score. This results point that
sunflower addition contributed to better utilization of
protein in corn flakes. As the score increases, these
data also show that the applied temperatures of ext-
rusion and drying (85 °C) do not lead to the loss of
lysine. Which is also the most reactive amino acid in
the Maillard reactions [9,19].
Table 2. Essential amino acids of corn flakes; the results are presented as mean±SD, different letter within the same column indi-
cates the significant difference in mean values (p < 0.05), according to Tukey’s HSD test. Experimental cases are explained in detail
in Table 1. Lys-lysine, Thr-threonine, Val- valine, Ile- Leu-Met- methionine, Phe- , His – histidine
Sample Essential amino acids, mg/g protein
Lys Thr Val Ile Leu Met Phe His
CF 1 24.99±0.20a 46.80±0.13e 31.03±0.43d27.81±0.43de 97.14±0.83abcd 19.02±0.14b33.31±0.25de 20.01±0.18f
CF 2 25.15±0.19a 50.29±0.30d 29.73±0.31ab 25.94±0.12b98.01±1.28bcd 19.17±0.20b31.17±0.09a 21.18±0.15a
CF 3 26.26±0.24b 50.15±0.34a 31.12±0.09c22.88±0.19c96.26±0.67abcd 20.02±0.28a31.17±0.23a 20.95±0.05a
CF 4 27.23±0.20c 52.11±0.40a 28.87±0.18ab 22.81±0.15c96.44±0.75abcd 19.83±0.11a29.22±0.24f 22.08±0.07b
CF 5 25.18±0.07a 54.14±0.18bc 29.26±0.22ab 27.08±0.22d98.05±0.78cd 19.84±0.12a32.77±0.26cd 19.12±0.20e
CF 6 25.04±0.34a 50.39±0.25bc 33.19±0.25d24.87±0.20f95.37±1.09a19.00±0.21b31.00±0.30a 21.88±0.12b
CF 7 27.20±0.06c 52.01±0.30a 29.77±0.22c26.00±0.41b95.53±0.82ab 20.83±0.20c32.09±0.17c 21.97±0.08b
CF 8 28.14±0.09d 53.93±0.32d 30.19±0.12ac 25.76±0.26b95.55±0.47abc 20.06±0.07a33.98±0.29e 22.80±0.07c
CF 9 26.03±0.09b 49.23±0.40c 29.01±0.11e28.22±0.24e98.76±0.55d17.84±0.16d34.92±0.09g 21.12±0.17a
CF 10 26.03±0.10b 53.77±0.42a 29.82±0.40ab 23.92±0.25a97.35±0.79abcd 18.95±0.23b30.12±0.39b 24.12±0.20g
CF 11 26.90±0.12c 52.23±0.53d 28.81±0.14b24.03±0.19a97.35±0.75abcd 20.15±0.29a30.87±0.16ab 22.90±0.08cd
CF 12 28.09±0.11d 51.52±0.44b 29.88±0.06c23.82±0.23a96.29±1.47abcd 20.88±0.14c30.93±0.45a 23.22±0.16d
M.B. KOŠUTIĆ et al.: NUTRITIVE CHARACTERISTICS OF CORN FLAKES Hem. ind. 71 (6) 495–502 (2017)
499
Table 3. ANOVA table for the prediction of amino acid corn flakes with sunflower and wild oregano
Parameter df Lys Thr Val Ile Leu Met Phe His
Sunflower 1 10.42a 9.60 7.35b 17.07b 2.02
c 4.27
b 2.82 6.67b
Sunflower 2 1 0.75
c 0.00 0.75 5.33c 0.75 0.00 10.08 3.00
Oregano 1 2.00b 8.00 0.50 0.00 0.13 0.00 3.12 4.50c
Oregano2 1 0.00 8.17 0.67 2.67 1.04 0.67 2.04 0.17
Sun.×Oreg. 1 0.00 1.60 1.60 0.90 0.02 0.90 1.23 0.40
Error 6 1.08 25.30 4.05 8.70 2.96 2.83 13.63 5.93
r2 0.924 0.520 0.728 0.749 0.572 0.673 0.586 0.713
aStatistically significant at p < 0.01 level; bstatistically significant at p < 0.05 level; cstatistically significant at p < 0.10 level
Table 4. Nutritive value protein of corn falkes; the results are
presented as mean±SD, different letter within the same column
indicates the significant difference in mean values (p < 0.05),
according to Tukey’s HSD test. Experimental cases are
explained in detail in Table 1
Sample Lys
Score amino acids PDCAAS
CF 1 0.56±0.01a 47.6±0.13a
CF 2 0.56±0.02a 47.7±0.23a
CF 3 0.58±0.03b 49.5±0.30b
CF 4 0.60±0.01c 51.3±0.33c
CF 5 0.56±0.04a 47.6±0.43a
CF 6 0.56±0.05a 47.7±0.63a
CF 7 0.60±0.05c 51.2±0.51c
CF 8 0.62±0.03d 53.0±0.48d
CF 9 0.56±0.01a 47.6±0.25a
CF 10 0.56±0.02a 47.7±0.21a
CF 11 0.60±0.02c 51.2±0.13c
CF 12 0.62±0.03d 53.0±0.20d
The purpose of PDCAAS evaluation of protein nutri-
tive value is the prediction of the overall efficiency of
protein utilization in terms of its two components,
digestibility and its amino acid score, i.e., score of
limiting amino acid [7]. PDCAAS values (Table 4) in corn
flakes increases, statistically significant, with the aug-
ment of sunflower content (samples with added 6 and
9 g) in the corn flakes due to higher digestibility of pro-
tein sunflower (90%) compared to the digestibility of
corn (85%) and also to sunflower compatible amino
acid pattern [7].
Most of the antioxidant potential in plant foods is
due to the properties of phenolic compounds, which
can act as reducing agents, free radical scavengers and
hydrogen donors [1,20,21]. It is known that oregano
possesses high antioxidant capacity [22,23] but our
study shows that dry residue of wild oregano (DR) is
also very powerful phenolic compounds and antioxid-
ant source (TPC 23,55 mg/g, DPPH 4,98 mg/ml, FRAP
8,45µg, Table 5), which completely changes the aspect
of its usage and well fits in the concept of better
valorization of food wastes. As the residue after distil-
lation of wild oregano oil was considered as waste mat-
erial, applied technology of corn flakes allows the rec-
overy of useful compounds and their recycling inside
food chain as functional additives. The phenolic com-
pounds and antioxidant activity of corn flakes (CF 1)
were relatively low (TPC 0.98 mg/g, DPPH 0.13 mg/ml,
FRAP 0.45 mg/g). Sunflower and dry residue wild ore-
gano (DR) addition strongly influenced the content of
phenolic compounds and antioxidant activity of corn
flakes. The highest content of phenolic compounds and
antioxidant activity (TPC 2.84 mg/g, DPPH 0.75 mg/ml,
FRAP 1,57 mg/g) was experienced with CF 12, corn
flakes with the highest amount of sunflower and dry
residue. Statistically significant differences in TPC, DPPH
and FRAP were observed between samples with inc-
reased oregano and sunflower content: CF 1–12, which
confirms that the addition of oregano and sunflower
increased the antioxidant activity of corn flakes, at sta-
tistically significant level (Table 5, Figure 1).
Table 6 shows the ANOVA calculations of the pre-
dictive model of the antioxidant activity values for corn
corn flakes with sunflower and wild oregano. It can be
seen from table that the SOP model for total phenols
content and DPPH calculation is mostly affected by the
linear terms of sunflower and oregano content, as well
as the non-linear term of product Sun.×Oreg., statistic-
ally significant at p < 0.01, The calculation of FRAP in
corn flakes is mostly affected by the linear terms of
sunflower and oregano content and the quadratic term
of sunflower content (p < 0.01).
The results indicate that all models were significant
with minor lack of fit, suggesting that they adequately
represented the relationship between responses and
factors.
M.B. KOŠUTIĆ et al.: NUTRITIVE CHARACTERISTICS OF CORN FLAKES Hem. ind. 71 (6) 495–502 (2017)
500
Table 5. Antioxidant activity of corn flakes with sunflower and wild oregano; the results are presented as mean±SD; different letter
within the same column indicates the significant difference in mean values (p < 0,05), according to Tukey’s test. Experimental cases
(samples) are explained in detail in Table 1; number of repetitions: n = 10, WO- wild oregano, DR- dry residue wild oregano,
SF-sunflower
Sample TPC, mg GAE/g sample DPPH *ARP (1/IC50) FRAP, mg AAE/g sample
WO 42.87±0.85 8.25±0.32 8.69±0.08
DR 23.55±0.75 4.98±0.06 8.45±0.03
SF 11.68±0.36 5.78±0.15 11. 01±0.05
CF1 0.98±0.03a 0.13±0.00a.h 0.45±0.01a
CF2 1.36±0.20b.e 0.20±0.00b.e 0.65±0.01b.f
CF3 1.62±0.10c.f 0.29±0.01c0.77±0.01c
CF4 1.88±0.05d.g.j 0.37±0.00d1.38±0.02d.h
CF5 1.18±0.01e.i 0.14±0.00a.h 0.46±0.01e
CF6 1.57±0.02f 0.21±0.01e0.68±0.01f
CF7 1.80±0.06g.j 0.34±0.00f0.95±0.00g.j
CF8 2.13±0.03h 0.45±0.02g1.35±0.03h
CF9 1.30±0.01i 0.16±0.02h0.50±0.01i
CF10 1.82±0.03
j
0.26±0.00i0.78±0.03
j
CF11 2.44±0.07k 0.40±0.01
j
1.08±0.02k
CF12 2.84±0.10l 0.75±0.00k1.57±0.01l
Figure 1. Observed responses of Leu, Met, His and Phe, based on the oregano and sunflower content.
M.B. KOŠUTIĆ et al.: NUTRITIVE CHARACTERISTICS OF CORN FLAKES Hem. ind. 71 (6) 495–502 (2017)
501
Table 6. ANOVA table for prediction of antioxidant value corn
flakes with flex sunflower and wild oregano
Parameter df Fenoli DPPH FRAP
Sunflower 1 2.377a 0.270a 1.629a
Sunflower2 1 0.010 0.007 0.052a
Oregano 1 0.913a 0.049a 0.067a
Oregano2 1 0.030b 0.003 0.003
Sun.×Oreg. 1 0.134+ 0.031a 0.008
Error 7 0.048 0.014 0.030
r2 0.987 0.961 0.984
aStatistically significant at p < 0,01 level; bstatistically significant at p <
0,10 level
CONCLUSION
Based on data resulting from the investigations of
quantity of sunflower and dry residue of wild oregano
addition influenced on corn flakes amino acid and anti-
oxidant potential it can be concluded:
Statistically significant differences between most
of the mean values of amino acids content and anti-
oxidant activity in the observed corn flakes were obs-
erved.
Sunflower and dry residue of wild oregano posi-
tively affect the phenolic compounds and antioxidant
activity. Maximum value obtained was TPC 2.84 mg/g,
DPPH 0.75 mg/ml, FRAP 1.57 mg/g with 9 g/100 g of
sunflower and 1 g/100 g dry residue of wild oregano in
CF 12.
Flakes product with addition of dry residues wild
oregano contributed to the food waste valorisation in
the food industry to obtain a new product with anti-
oxidant potential.
Lysine is limiting amino acid for all corn flakes
(CF1–12).
The temperature extrusion (85 °C) does not lead
to the loss of lysine as well as the most reactive amino
acids.
Score and PDCAAS value in corn flakes (CF1–12)
increases with increasing of adding sunflower (3, 6, or 9 g).
Acknowledgements
These results are part of the project supported by
the Ministry of Education, Science and Technological
Development of the Republic of Serbia, III 46005 and
TR 31027.
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IZVOD
POBOLJŠANJE NUTRITIVNIH OSOBINA KORN FLEKSA OBOGAĆENOG FUNKCIONALNIM KOMPONENTAMA
Milenko B. Košutić1, Lato L. Pezo2, Jelena S. Filipović1, Vladimir S. Filipović3
1Naučni Institut za prehrambene tehnologije u Novom Sadu, Bul. cara Lazara 1, 21000 Novi Sad, Srbija
2Institut za opštu i fizičku hemiju, Univerzitet u Beogradu, Studentski Trg 12–16, 11000 Beograd, Srbija
3Tehnološki fakultet, Univerzitet u Novom Sadu, Bul. cara Lazara 1, 21000 Novi Sad, Srbija
(Naučni rad)
Tokom procesa proizvodnje hrane stvara se velika količina sporednih proiz-
voda koji zave kao otpad. Sporedni proizvodi predstavljaju veliki problem pri-
likom odlaganja, potencijalno veliki izvor zagađenja i veliki gubitak biomase i
hranljivih materija. Savremeno društvo, u kome postoji velika potražnja za pre-
hrambenim proizvodima poboljšanog nutritivnog sastava, karakteriše rast troš-
kova proizvodnje hrane i smanjena dostupnost sirovina. Trend rasta potražnje
prehrambenih proizvoda poboljšane nutritivne vrednosti, sa dodatkom različitih
bioaktivnih komponenti ili nenutrijenata sa pozitivnim efektima na zdravlje, uti-
calo je na povećanje iskorišćenja sporednih proizvoda. Podizanje svesti potrošača
o značaju nutrutivnog sastava prehrambenih proizvoda za očuvanjem zdravlja
uticala je i na proizvođače. Danas je prehrambena industrija sve više usmerena
prema pobolј
š
anju kvaliteta i zdravstvene bezbednosti namirnica. U skladu sa
savremenim stavovima nutricionista, proizvodi od žitarica, su najčešća hrana u
svakodnevnoj ishrani kao što suready to eat žitarice za doručak fleks i snek
proizvodi. Ekstruziona tehnologija omogućava primenu različitih tehnologija i
različite izvore za obogaćivanje ekstrudiranih proizvoda na bazi žitarica. Ovaj rad
istražuje efekte dodavanja suncokreta (3, 6 i 9 g/100 g uzorka) i suvog ostatka
divljeg origana (0,5 g/100g uzorka i 1 g/100g uzorka) na aminokiselinski sastav i
antioksidativni potencijal fleks proizvoda u cilju dobijanja novog proizvoda sa
poboljšanim funkcionalnim svojstvima. Eksperimentalni plan je 3×4. Rezultati
Score i PDCAAS vrednosti fleks proizvoda se povećavaju sa povećanjem udela
suncokreta. Maksimalna vrednost fenolnih jedinjenja (TPC 2,84 mg/g) i antioksi-
dativnog potecijala (DPPH 0,75 mg/ml, FRAP 1,57 mg/g) je zabeležena kod fleks
proizvoda sa maksimalnim udelom suncokreta i suvog ostatka divljeg origana.
Tukey’s HSD test je pokazao statistički značajne razlike između aminokiselinskog
sadržaja i antioksidativnog potecijala posmatranog korn fleks proizvoda. Metoda
odzivne funkcije (površine) je primenjena za procenu fleks proizvoda. Dodatak
suncokreta pozitivno utiče na nutritivnu vrednost, a dodatak suvog ostatka divljeg
origana na antioksidativnu aktivnost fleks proizvoda i doprinosi boljoj valorizaciji
sporednih proizvoda iz prehrambene industrije. Fleks proizvod sa dodatkom sun-
cokreta i suvog ostatka divljeg origana je nov proizvod sa poboljšanim sastavom
esencijalnih aminokiselina i antioksidativnim potencijalom pri čemu ima sve
osobine funkcionalne hrane.
Ključne reči: Amino kiseline Antioksi-
dativnost Divlji origano Suncokret
Fleks proizvod
... Optimum values of cohesiveness of grain mixtures characterize their ability to move freely when unloaded from containers and during transportation [6]. The obtained results correlate with the data, determined on the physical and technological parameters of corn flakes [37,38]. ...
... Scientists note that whole grain products are essential for daily diets; they contain a unique set of nutrients that are prevention of cardiovascular disease and diabetes [37]. ...
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