Influence of harvest year in the physicochemical properties and
                    antioxidant activity of flaxseed hull oils from Tunisia

Herchi, Wahid; Bahashwan, Saleh; Sakouhi, Faouzi; Boukhchina, Sadok

doi:10.1590/1678-457X.6579

Acessibilidade / Reportar erro

Brasil

Food Science and Technology

Español English

Brasil

Español English

sumário « anterior atual seguinte »

Sumário

Research Paper • Food Sci. Technol (Campinas) 35 (1) • Jan-Mar 2015 • https://doi.org/10.1590/1678-457X.6579 copy

Influence of harvest year in the physicochemical properties and antioxidant activity of flaxseed hull oils from Tunisia

Authorship SCIMAGO INSTITUTIONS RANKINGS

The objective of this research was to determine the effect of five years on physico-chemical characteristics and antioxidant activity of flaxseed hull oils. Oil and protein on flaxseed hull varied between 20.15 and 22.56 and 17.45 and 19.14, respectively. The albumin fraction dominated the seed hull protein composition (44 - 47%). Flaxseed hull oils showed significantly high unsaturated to saturated fatty acid ratios (6.61 - 8.36) and calculated oxidizability (Cox) values (10.88 - 12.30). The physiochemical parameters determined included saponification value (SV) (174 -182 mg KOH/g), unsaponifiable matter (UM) (1.32 - 1.64%), peroxide value (PV) (1.70 - 2.20 mequiv/kg), Oxidation value (OV) (4.40 - 5.90) and oil stability (1.10 - 1.42 h). The highest content of total phenolic acids and total tocopherols were recorded on hull sample collected in 2008. Flavanoid content ranged from 11 to 19 mg/100 g oil. Antioxidant activity differed significantly; the greatest inhibition (61.38%) was for the hull sample collected in 2008.

flaxseed hull oil; antioxidant activity; chemical composition

Years	2005	2006	2007	2008	2009
Moisture (%)	6.79±0.32^a	6.28±0.20^a	5.85±0.57^b	6.12±0.42^b	7.87±0.35^a
^{Dils (%)}	^20.15±0.46 ^a	^21.70±0.22 ^a	^22.56±0.14 ^b	^21.45±0.38 ^a	^20.36±0.26 ^a
^{Protein (%)}	^17.45±0.20 ^a	^19.14±0.24 ^b	^18.42±0.38 ^b	^18.32±0.44 ^a	^17.50±0.31 ^a
^{Ash (%)}	^4.10±0.10 ^a	^5.23±0.19 ^a	^5.11±0.15 ^a	^4.60±0.12 ^a	^5.73±0.23 ^a
^{Total carbohydrate (%)}	^51.51±0.41 ^a	^47.65±0.43 ^a	^48.06±0.26 ^a	^49.51±0.21 ^a	^48.54±0.36 ^a
^{Ascorbic acid (Vitamin C)}	^1.27±0.05 ^a	^1.44±0.17 ^a	^1.71±0.12 ^a	^1.30±0.10 ^a	^1.82±0.14 ^a
^{Digestible protein (%)}	^12.54±0.12 ^a	^14.16±0.11 ^b	^13.47±0.16 ^b	^13.38±0.10 ^b	^12.59±0.12 ^a
^{energy (kcal/ 100g)}	^464±0.42 ^a	^469±1.16 ^a	^475±1.12 ^b	^471±0.87 ^b	^454±0.92 ^a
^{energy (kj/ 100g)}	^1943±1.56 ^a	^1964±3.72 ^a	^1989±3.68 ^b	^1972±2.70 ^b	^1901±3.18 ^a

Years	2005	2006	2007	2008	2009
Osborn protein fraction
Albumin	45±1.26^a	47±1.70^b	44±1.23^a	47±1.59^b	45±1.19^a
Globulin	41±0.77^a	40±0.89^a	39±0.66^b	41±0.31^a	40±0.49^a
Prolamin	4±0.14^a	4±0.10^a	6±0.18^b	4±0.10^a	5±0.12^a
Glutelin	9±0.22^a	8±0.19^a	10±0.26^b	7±0.29^a	9±0.24^a

Years	2005	2006	2007	2008	2009
Saturated fatty acids (SFA) C16I:0 (palmitic acid)	7.38±0.08^a	7.25±0.12^a	6.94±0.06^a	7.40±0.10^a	7.31±0.11^a
^{C18I:0 (stearic acid)}	^4.12±0.05 ^a	^4.36±0.06 ^a	^3.53±0.05 ^a	^3.58±0.07 ^a	^5.71±0.07 ^a
^Total	^11.50±0.13 ^a	^11.61±0.18 ^a	^10.47±0.11 ^a	^10.98±0.17 ^a	^13.02±0.18 ^a
^{Monounsaturated fatty acid (MuFA)} C18I:1 (oleic acid)	23.10±0.18^a	22.89±0.15^a	24.78±0.22^a	23.11±0.20^a	28.24±0.24^b
^Total	^23.10±0.18 ^a	^22.89±0.15 ^a	^24.78±0.22 ^a	^23.11±0.20 ^a	^28.24±0.24 ^b
^{Polyunsaturated fatty acids (PuFA)} C18I:2 (linoleic acid) ω6	15.84±0.18^a	17.31±0.20^b	16.21±0.18^a	16.71±0.22^b	16.77±0.26^b
^{C18I:3 (linolenic acid)ω3}	^48.52±0.51 ^a	^47.03±0.34 ^b	^46.64±0.62 ^b	^47.91±0.39 ^a	^41.07±0.42c
^Total	^64.36±0.69 ^a	^64.34±0.54 ^a	^62.85±0.80 ^b	^64.62±0.61 ^a	^57.84±0.68 ^b
^eFA	^64.36±0.69 ^a	^64.34±0.54 ^a	^62.85±0.80 ^b	^64.62±0.61 ^a	^57.84±0.68 ^b
^uFA	^87.46±0.87 ^a	^87.23±0.69 ^a	^87.63±1.02 ^a	^87.73±0.81 ^a	^86.08±0.92 ^a
^{ω3/ ω6 ratio}	^3.06±0.18 ^a	^2.71±0.14 ^a	^2.87±0.20 ^a	^2.86±0.16 ^a	^2.45±0.12 ^b
^{Linolenic /Dleic ratio}	^2.10±0.20 ^a	^2.05±0.12 ^a	^1.88±0.22 ^b	^2.07±0.14 ^a	^1.45±0.17 ^b
^{PuFA/ SFA}	^5.59±0.24 ^a	^5.54±0.18 ^a	^6.00±0.16 ^a	^5.88±0.26 ^a	^4.44±0.14 ^b
^uFA/SFA	^7.60±0.31 ^a	^7.51±0.28 ^a	^8.36±0.32 ^b	^8.00±0.38 ^b	^6.61±0.22 ^a
^MuFA/PuFA	^0.35±0.04 ^a	^0.35±0.04 ^a	^0.39±0.05 ^a	^0.35±0.03 ^a	^0.49±0.06 ^b
^{Cox value}	^12.28±0.14 ^a	^12.17±0.12 ^a	^12.00±0.10 ^a	^12.30±0.15 ^a	^10.88±0.08 ^b
^DDR	^73±0.74 ^a	^73±0.70 ^a	^71±0.43 ^a	^73±0.56 ^a	^67±0.37 ^b
^LDR	^75±0.58 ^a	^73±0.66 ^a	^74±0.55 ^a	^74±0.50 ^a	^71±0.40 ^a
^{Physicochemical properties} Relative density at 25 ºC/g cm-3	0.941±0.02^a	0.938±0.01^a	0.940±0.01^a	0.935±0.02^b	0.937±0.01^b
^{Saponification value (mg kDH/g)}	^180±0.62 ^a	^179±0.55 ^a	^176±0.50 ^b	^182±0.47 ^a	^174±0.53 ^b
^{Acid value (mg kDH/g)}	^1.76±0.10 ^a	^1.68±0.08 ^a	^1.62±0.14 ^b	^1.42±0.12 ^b	^1.85±0.09 ^a
^{Iodine value (g I2/100 g)} Determined	175±0.78^a	174±0.90^a	170±0.88^b	177±1.06^a	163±0.65^b
^Calculated	^174±0.57 ^a	^173±0.82 ^a	^171±0.59 ^b	^174±1.19 ^a	^161±0.84 ^b
^{unsaponifiable matter (% w/ w)}	^1.64±0.24 ^a	^1.47±0.18 ^a	^1.39±0.22 ^a	^1.78±0.26 ^a	^1.32±0.14 ^a
^a ^{Triglyceride (%)}	^97.41±0.45 ^a	^97.63±0.82 ^a	^97.76±0.70 ^a	^97.40±0.60 ^a	^97.58±0.23 ^a
^{Average molecular weight (g/mol)}	^935±3.62 ^a	^940±2.87 ^a	^956±3.14 ^a	^925±2.91 ^a	^967±2.76 ^a

Years	2005	2006	2007	2008	2009
FFA (% of Oleic acid)	0.95±0.06^a	0.90±0.10^a	0.85±0.05^a	0.82±0.08^a	1.10±0.08^b
Peroxide value (mequiv/kg)	2.10±0.22^a	2.00±0.33^a	1.90±0.16^b	1.70±0.25^b	2.20±0.18^a
p-Anisidine value	1.70±0.12^a	1.55±0.10^a	1.35±0.14^b	1.00±0.19^a	1.20±0.15^b
Oxidation value	5.90±0.54^a	5.55±0.62^a	5.15±0.33^b	4.40±0.18^a	5.60±0.44^b
Flavor score	5.63±0.14^a	5.75±0.15^a	5.89±0.10^a	6.16±0.13^a	5.74±0.15^a
Oil stability (h)	1.14± 0.05^a	1.26±0.08^a	1.35±0.10^b	1.42±0.04^a	1.10±0.04^a
K₂₃₂	1.55±0.06^a	1.50±0.08^a	1.45±0.05^a	1.60±0.06^a	1.40±0.09^a
K₂₇₀	0.25±0.02^a	0.23±0.01^a	0.22±0.01^a	0.27±0.02^a	0.20±0.03^a
R-value (K₂₃₂/ K₂₇₀)	6.2±0.08^a	6.5±0.10^a	6.6±0.06^a	5.9±0.12^a	7±0.08^a

Years	2005	2006	2007	2008	2009
Phenolic acids
^{ferulic acid equivalents (mg/ 100 g oil)}	^90±1.68a	^91±1.05a	^88±1.32b	^94±1.46a	^86±1.19b
^Flavanoids
^{luteolin equivalents (mg/100 g oil)}	^19±0.60a	^15±0.87b	^17±0.48a	^14±0.74b	^11±0.52b
^{Chlorophyll (mg /kg oil)}	^2.8±0.33a	^2.4±0.20a	^2.6±0.35a	^2.2±0.27a	^2.4±0.18a
^{Carotenoids (mg /kg oil)}	^8.2±0.37a	^7.2±0.51a	^7.6±0.35a	^7.5±0.42a	^7.8±0.24a
^{TS Content (% of oil)}	^1.15±0.12a	^0.98±0.18b	^0.92±0.10b	^1.33±0.15a	^0.80±0.10b
^{TT content}
^{(mg α-tocopherol/kg oil)}	^196±5.26a	^210±6.10a	^226±4.32b	^239±6.08b	^188±4.47a

Sociedade Brasileira de Ciência e Tecnologia de Alimentos Av. Brasil, 2880, Caixa Postal 271, 13001-970 Campinas SP - Brazil, Tel.: +55 19 3241.5793, Tel./Fax.: +55 19 3241.0527 - Campinas - SP - Brazil
E-mail: revista@sbcta.org.br

Acompanhe os números deste periódico no seu leitor de RSS

[1] *Corresponding author: wahid1bio@yahoo.fr