Tiger Nut Oil Research Articles

Effect of Enzyme Pre-treatments on Bioactive Compounds in Extracted Tiger Nut Oil and Sugars in Residual Meals.

Tiger nut oil is a novel oil that requires more research data on its characteristics. In this study, the oil was extracted using both enzyme-aided pressing (EAP) and aqueous enzymatic extraction (AEE) methods. Using enzymes as a pre-treatment prior to mechanical pressing increased the concentration of some phenolic acids and tocopherols present in extracted oils compared to controls. High pressure processing as a pre-treatment before aqueous enzymatic extraction also enhanced tocopherols and total polyphenolic content in oils. The percentage free fatty acid and peroxide values indicated that under the initial extraction parameters, the oils were stable and they all met the standards for virgin olive oil set by the International Olive Oil Council. Residual meals from both extraction processes contained low protein contents ranging from 2.4 to 4.6 %. Additionally, EAP and AEE meals contained low DP (degree of polymerisation) sugars that appeared as 1-kestose (DP3) and nystose (DP4). EAP had the highest total DP3 and DP4 sugar content of 82.5 mg/g. These sugars would need further assessment to verify their identity and determine their suitability as a potential food.

Enhancing the recovery of tiger nut (Cyperus esculentus) oil by mechanical pressing: Moisture content, particle size, high pressure and enzymatic pre-treatment effects

Tiger nut (Cyperus esculentus) tuber contains oil that is high in monounsaturated fatty acids, and this oil makes up about 23% of the tuber. The study aimed at evaluating the impact of several factors and enzymatic pre-treatment on the recovery of pressed tiger nut oil. Smaller particles were more favourable for pressing. High pressure pre-treatment did not increase oil recovery but enzymatic treatment did. The highest yield obtained by enzymatic treatment prior to mechanical extraction was 33% on a dry defatted basis, which represents a recovery of 90% of the oil. Tiger nut oil consists mainly of oleic acid; its acid and peroxide values reflect the high stability of the oil.

Tiger nut oil (Cyperus esculentus L.): A review of its composition and physico‐chemical properties

AbstractDespite its high nutritional value, tiger nut oil is hardly used in food industries compared to other vegetable oils such as olive and peanut oil. However, its benefits are increasingly being recognized, including its stability and similarity to olive oil in particular. This review discusses its composition, physico‐chemical properties and economic potential. Literature reveals that tiger nut oil shares a similar fatty acid profile with olive, avocado and hazelnut oil. Its low content of polyunsaturated fatty acid, tocopherol and phytosterol contributes to its high stability. When compared to soy bean oil, its phospholipids composition (3.1–5.4%) is higher. Its iodine and acid values reflect its quality at 76.60 and 0.03 mg KOH/g oil, respectively. Roasted tiger nut oil was found to contain vanillin and to a lesser extent 2, 3‐dihydro‐3, 5‐dihydroxy‐6‐methyl‐4H‐pyran‐4‐one and 5‐ethylfurfural as key odorants contributing to the overall aroma of the oil. Its low viscosity makes it suitable for use in coating industry and as fuel. In‐depth studies on the oils' constituents are on‐going but efficient and environmentally friendly extraction techniques are needed. Based on the available data, tiger nut oil has been established as an oil of good nutritional value which may be exploited to the great benefit of growers, processors and dealers of the tuber.This review discusses the composition, physico‐chemical properties and economic potential of tiger nut oil.

Physicochemical studies on sunflower oil blended with cold pressed tiger nut oil during deep frying process

Sunflower oils were blended with different levels of cold pressed tiger nut oil. Blended oils were obtained by mixing tiger nut oil with sunflower oil at the volume ratios of 0:100, 10: 90, 20: 80, 30: 70, 40: 60, 50:50 and 100: 0. The effects of deep frying on physico-chemical parameters (Free Fatty Acid (FFA), Peroxide Value (PV), thiobarbituric acid value (TBA), iodine value, Total Polar Compounds (TPC), color and viscosity) were evaluated over 30 hours of the frying process. The total phenolic content of native oils was determined. GLC analysis was performed to illustrate the fatty acid composition of sunflower oil, tiger nut oil and binary mixtures of them as well as their oxidation rates. The pure and blended oils were heated at 180 °C ± 5 °C, then frozen French fried potatoes were fried every 30 min. Oil samples were taken every 5 h and the entire continuous frying period was 30 h. The results showed that fresh sunflower oil had significantly the highest value of COX (7.25); while tiger nut oil had significantly the lowest (2.24). Mixing sunflower oil with different levels of tiger nut oil led to an increase in its stability against oxidation. The phenolic content of cold pressed tiger nut oil was about 3.3 times as high as that of sunflower oil. The analytical data showed that the lowest deterioration during the frying process occurred in tiger nut oil and the highest in sunflower. The changes in the physico-chemical parameters were controlled and significantly (P < 0.05) decreased when tiger nut /sunflower oil (W/W) proportions were varied between 20/80 to 50/50. The obtained results indicate that mixing sunflower oil with cold pressed tiger nut oil increased the stability and hence improved the quality of sunflower oil during the frying process.

Volatile constituents of roasted tigernut oil (Cyperus esculentus L.)

Volatile compounds play a key role in determining the sensory appreciation of vegetable oils. In this study a systematic evaluation of odorants responsible for the characteristic flavour of roasted tigernut oil was carried out. A total of 75 odour-active volatiles were identified. From these, 13 aroma compounds showing high flavour dilution factors in the range of 16 to 128 were quantified by their odour activity values (OAVs). On the basis of high OAVs in oil, the following aroma compounds [vanillin (chocolate, sweet vanilla), 5-ethylfurfural (caramel, spicy), 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one (caramel), phenyl acetaldehyde (honey-like), ethanone, 1-(4-hydroxy-3-methoxyphenyl) (faint vanilla)] were elucidated as important contributors to the overall chocolate, sweet vanilla, butterscotch aroma of the oil. Odorants with high concentrations in the roasted tigernut oil such as 5-hydroxymethylfurfural, ethyl hexadecanoate, n-propyl-9,12-octadecadienoate gave relatively low OAVs, so their contributions to the overall orthonasal aroma impression of roasted tigernut oil can be assumed to be low.

Studies on the hypolipidemic effects of Coconut oil when blended with Tiger nut oil and fed to albino rats

Hyperlipidemia is a predominant risk factor for atherosclerosis and associated cardiovascular diseases (CVD). The international guidelines issued by the World Health Organization recommend a reduction in dietary saturated fat and cholesterol intake as a means to prevent hypercholesterolemia and CVD. The main objective of the current investigation was to evaluate the effects of feeding blended oils consisting of coconut oil (CNO) with different proportions of Tiger nut oil (TNO) on serum lipid levels in Albino rats. GLC analysis was performed to illustrate the fatty acid composition of the blended oils. Blended oils were obtained by mixing tiger nut oil with coconut oil at the volume ratios of 100:0, 70:30, 50:50, 25:75, 10:90 and 0:100. Fifty-six male albino rats were randomly divided into 7 groups of 8 rats each according to the oil type. The blended oils were fed to rats for a period of up to 10 weeks. Total cholesterol (T-Ch), high-density lipoprotein cholesterol (HDL-Ch), low-density lipoprotein cholesterol (LDL-Ch), and triglycerides (TG), were determined. The atherogenic Index (AI) was calculated. The results showed that non-significant changes in all nutritional parameters were observed between the control group and the rats fed with the tested oils. The results also indicate that coconut oil had 86% saturated fatty acids. On TNO contains 66% oleic acid. Therefore, blending coconut oil with tiger nut oil can reduce the proportions of saturated to unsaturated fatty acids in CNO. The rats that were fed blended oils showed significantly reduced levels of serum cholesterol as compared to those fed CNO. The HDL levels were marginally enhanced in the rats that were fed blended oils. The total cholesterol and LDL cholesterol levels were controlled when TNO/CNO proportions varied between 25/75 and 70/30. This was reflected in the calculation of the atherogenic index. Similar changes were observed with serum triglyceride levels.

Physicochemical Studies on Sunflower Oil Blended with Cold Pressed Tiger Nut Oil, during Deep Frying Process

Blends consisting of sunflower oil and cold pressed tiger nut oil in different proportions were evaluated for various physicochemical parameters over 30 hours of frying process. The phenolic content of native oils was determined. Some physical and chemical parameters (Free Fatty Acid, FFA), Peroxide Value (PV), thiobarbituric acid value, iodine value, Total Polar Compounds (TPC), color and viscosity of fresh and fried blended oils measured at different frying periods. Native and blended oils were heated at 180°C+5°C, then frozen French fries potato were fried every 30 min. Oil samples were taken every 5 hours and the entire continuous frying period was 30 hours. The results showed that phenolic content of cold pressed tiger nut oil was about 3.3 times higher than that of sunflower oil. The analytical data showed that the lowest deterioration during frying process occurred in tiger nut oil and the highest in sunflower. The changes of physicochemical parameters were controlled and significantly (P<0.05) decreased when tiger nut /sunflower oil (W/W) proportions were varied between 20/80 to 50/50. The obtained results indicate that mixing sunflower oil with cold pressed tiger nut oil increased the stability and hence improved the quality of sunflower oil during frying process.

Compositional and structural studies of the oils from two edible seeds: Tiger nut, Cyperus esculentum, and asiato, Pachira insignis, from Ghana

A comprehensive lipid profiling has been carried out on the seed oils of tiger nut, Cyperus esculentum, and asiato, Pachira insignis, from Ghana in order to evaluate their potential uses for the region. Composition of FAs and phytosterols were determined using GC–MS, while tocol composition was determined with HPLC. TAG composition and regiochemistry were determined using ES-FTICR-MS and 13C NMR, respectively. The major FA components in asiato seed oil were palmitic acid (56.58%) and sterculic and dihydrosterculic acids (20.06% combined). The major FA components in tiger nut oil were oleic (65.55%), palmitic (16. 32%), and linoleic (12.13%) acids. Asiato seed oil had 18 major TAG classes, dominated by, C51:1 (38.45%) and C50:1 (13.941%). Tiger nut oil had 7 major TAG classes, with C54:3 (29.00%) and C52:2 (27.82%) dominating. The sn-1/3 and sn-2 positions in the TAGS for asiato oil were predominantly occupied by saturated acyl chains (87.25%) and cyclic acyl chains (71.44%), respectively. Oleoyl chain primarily occupied both sn-1/3 (52.68%) and sn-2 (77.62%) positions in the tiger nut oil. Total tocol content in asiato oil was 200.31μg/g, with γ-tocopherol (182.99μg/g) dominating. Tiger nut oil had a total tocol content of 120.10μg/g, dominated by α-tocopherol (86.73) and β-tocopherol (33.37μg/g).Tiger nut oil had total 4-desmethylsterol content of 986μg/g, dominated by β-sitosterol (517.25μg/g) and stigmasterol (225.25μg/g), while asiato oil had total desmethylsterol content of 590.24μg/g, dominated by β-sitosterol (518.91μg/g). The presence of cyclopropenoid FAs in asiato oil makes it unsuitable for food uses. Tiger nut oil can replace imported olive oil in food products in the West African region.

Haematological Parameters Of Albino Rats Fed On Tiger Nuts (Cyperus Esculentus) Tuber Oil Meal-Based Diet.

The effect of Cyperus esculentus (tiger nut) tuber oil meal-based diet on the haematological parameters of albino rats was studied. Cyperus esculentus tuber oil was extracted from the tuber using a soxhlet extractor. Twenty, 3 weeks-old albino rats (Rattus norvegicus) with an initial average weight of 51.67±5.29g were grouped into two groups of ten (10) animals each. The first group was fed with soybean oil-based (control) diet; the second group on esculentus tuber oil meal-based diet for six (6) weeks. There was no significant difference (p>0.05) in all the Haematological parameters which include Haemoglobin (Hb), Red blood cells (RBC), Packed cell volume (PCV), Mean cell volume (MCV), Mean cell haemoglobin (MCH), Mean cell haemoglobin concentration (MCHC), White Blood Cells (WBC) and platelets in the serum of Tiger nut oil based diet fed rats as compared to that of the soybean oil. We concluded that feeding rats with tiger nut oil based diets is safe, does not cause anemia and will not allow accumulation of toxic material in the body.

STUDIES ON TIGER NUT AND IT’S PRODUCTS

The study aimed to know the nutritional value of defatted tiger nut flour and tiger nut oil . Also, use tiger nut flour in cake and biscuit and analysis oil form tiger nut . The study showed that the defatted tiger nut flour had a relatively good amounts of protein (10.1 %) result to extract fat and decreases in fiber. Good amounts of essential amino acids which indicate the high nutritional value of these flour and the results showed a very good source of Iron.. The fatty acid pattern revealed that the saturated fatty acid content was (19.1%) while the unsaturated fatty acid content was (80.9 %). Also the wheat flour was replaced by 25 , 50 and 75% of defatted tiger nut flour and effect of this replacement on the gross chemical composition, mineral and amino acid content. The sensory evaluation of cake and biscuit products (all mixtures) were highly acceptable and having good sensory attributes

A preliminary investigation into the biofuel characteristics of tigernut ( Cyperus esculentus) oil

Laboratory scale experiments were carried out to produce and characterise biofuel from tigernut ( Cyperus esculentus) oil. Transesterification of tigernut oil afforded methyl and ethyl esters, which had fuel properties similar to common biofuels, hence tigernut could be utilised as an alternative renewable energy resource.