Defatted Peanut Meal Research Articles

Novel Umami-, Salty-, and Kokumi-Enhancing γ-Glutamyl Tripeptides Synthesized with the Bitter Dipeptides from Defatted Peanut Meal Protein Hydrolysate.

Defatted peanut meal protein hydrolysates (DPMHs) usually have a bitter taste. γ-Glutamylation by Bacillus amyloliquefaciens l-glutaminase was introduced to DPMH to reduce its bitterness and generated a γ-glutamylated product (DPMH-G). Extra l-glutamine (l-Gln) (5% w/w) was added to DPMH, and the mixture was then γ-glutamylated (DPMH-G-Q). Results showed that γ-glutamylation decreased the bitterness of the products and also enhanced their kokumi, umami, and salty taste, especially for DPMH-G-Q. Bitter amino acids and bitter peptides were found to be substrates (acceptors) of the synthesized γ-[Glu](1,2)-AAs and γ-Glu-AA-AAs, respectively. The production yield of γ-[Glu](1,2)-AAs was only 0.69/100 g for DPMH-G and 2.30/100 g for DPMH-G-Q, which was much lower than that of γ-Glu-AA-AAs (5.73/100 g for DPMH-G and 18.72/100 g for DPMH-G-Q). The improvement in taste attributes of DPMH might mainly be due to the consumption of bitter dipeptides and the production of γ-Glu-AA-AAs. In DPMH-G-Q, eight γ-Glu-AA-AAs were identified, including γ-Glu-Ile-Lys, γ-Glu-Ala-Ile, γ-Glu-Leu-Leu, γ-Glu-Phe-Leu, γ-Glu-Thr-Leu, γ-Glu-Ile-Met, γ-Glu-Val-Leu, and γ-Glu-Ser-Tyr, which were first time reported. They all can enhance umami, salty, and kokumi taste with a threshold value between 1.61 ± 0.21-2.16 ± 0.19, 1.65 ± 0.19-2.23 ± 0.20, and 0.67 ± 0.21-1.00 ± 0.22 mM, respectively. Insufficient l-Gln restricted the formation of γ-glutamyl peptides, and this was why DPMH-G had a lower yield and variety than DPMH-G-Q. This also suggested that l-glutaminase is selective to different substrates. Overall, this study provides a new method to reduce the bitterness of protein hydrolysates and also improve the taste by synthesizing γ-glutamyl tripeptides.

Formulation, Optimization and Characterization of Dietary Cookies from Blends of Corn, Peanut, Sweet Potato and Soybean

Traditionally wheat is used for cookies production but the harsh climatic conditions in the tropical regions is not conducive for the growth of wheat. There are locally grown crops that can be used to produce high quality cookies that meet consumer’s dietary requirements. The aim of this study was to develop, characterize, and optimize the formulation and some production processes of dietary cookies from blends of corn, peanut, sweet potato and soybean. A four-component, constrained, randomized, combined, D-optimal mixture-process experimental design; with 34 randomized experimental runs, was employed. The formulation design constraints were: roasted corn flour (20% - 70%), defatted peanut meal (10% - 30%), blanched soybean (10% - 30%), and sweet potato extract/gel (5% - 20%). The four major components comprise 95% of the total mixture. Other minor components of the formulation, which were kept constant throughout the experimentation, were: sugar (1 %), baking powder (0.8 %), baking fat (0.2 %), and water (3 %). The processing parameters investigated were: baking temperature (120°C - 180°C) and baking time (10min – 25min). The formulated dietary cookies were analyzed and evaluated for the proximate properties, physicochemical properties and sensory characteristics using standard procedures. The result of the dietary cookies optimization gave optimal formulated dietary cookie with overall desirability index of 0.531, based on the set optimization goals and individual quality desirability indices. The optimal cookie was obtained from 22.744% roasted corn, 26.589% defatted peanut, 25.666% blanched soybean, 20.0% sweet potato extract/gel, 1380C baking temperature, and 25 minutes baking time. The quality properties of this optimal cookies are 14.071% moisture content, 25.699% crude protein, 4.957% crude fibre, 16.033% fat content, 34.388% carbohydrate, 7.234% ash content, 386.440 Kcal/100g energy value, 381.514 mg/100g potassium, 80.0 mg/100g calcium, 3.789 mg/100g iron, 0.552 mg/100g zinc, 75.088% digestibility, 20.566 D/T spread ratio, 0.657 g/cubic cm bulk density, 1.695g breaking strength, and overall acceptability of 5.96, based on 9-point hedonic scale. The result of the study showed that the formulated dietary cookies was of high quality and that improving nutritional quality of cookies is possible through composite formulation. It is recommended that further study be carried out on formulation of nutritionally improved dietary cookies using other nutritionally rich roots and legumes. Enrichment of cookies with these protein-rich sources will result in cookies with improved nutrient quality that meets the consumer’s dietary needs.

Optimization of protein hydrolysates production from defatted peanut meal based on physicochemical characteristics and sensory analysis

Three enzymes, GA (Genencor Alkaline Protease), GN (Genencor Neutral Protease) and Protamex were used to prepare protein hydrolysates from defatted peanut meal (DPM). The physicochemical properties of defatted peanut meal hydrolysate (DPMH) and the changes of flavor were determined. DPMHs had lower isoelectric points, zeta potential values and better solubility. The DPMH of GN showed the best emulsifying activity and the emulsion stability. Volatile organic compounds (VOCs) changed significantly with the most drastic changes at 4–6 h. About 50 VOCs were labeled using GC-IMS. The fingerprint of smell change was established, and the enzymolysis reaction could be divided into different stages according to the change of flavor. DPMHs of GA and Protamex showed stronger astringency and bitterness, while stronger umami was shown in DPMH of GN. This research provides basic data support for enzyme selection, sensory and reaction stage control to obtain enzymatic polypeptides with improved properties from DPM.

Comparative Evaluation of the Antioxidant Properties of Whole Peanut Flour, Defatted Peanut Protein Meal, and Peanut Protein Concentrate

Defatted peanut meal is a low value agro-industrial residue from peanut oil production with potential use as a value addition food ingredient. In this study, peanuts were roasted at 100°C for 5 min, de-skinned and milled into whole peanut flour (WPF) from which the defatted meal (DPM) was prepared by acetone extraction and the peanut protein concentrate (PPC) obtained from the DPM using isoelectric pH precipitation. The protein content, amino acid profile, total phenolic content (TPC), total flavonoid content (TFC) and in vitro antioxidant properties of the peanut samples were then determined. Results showed that DPM had a TPC of 0.12 ± 0.02 mg gallic acid equivalent (GAE)/g, which was significantly (p < 0.05) higher than and twice the levels in WPF and PPC (0.06 ± 0.03 mg GAE/g). However, WPF had TFC of 0.21 ± 0.01 μg quercetin equivalent (QE)/g, which was significantly (p < 0.05) higher than DPM (0.16 ± 0.03 μg QE/g) and PPC (0.11 ± 0.05 μg QE/g). However, PPC had superior amino acid profile in addition to stronger radical scavenging and metal chelation activities than WPF and DPM. The results suggest that PPC is a protein rich product that could be utilized as an ingredient in food product fortification to enhance nutritional quality and in the formulation of functional foods with antioxidant benefits.

Antioxidant Properties of Maillard Reaction Products from Defatted Peanut Meal Hydrolysate-Glucose Syrup and its Application to Sachima

Antioxidant properties of defatted peanut meal (DPM) hydrolysate-glucose syrup Maillard reaction products (MRPs) were evaluated, and their effects on the oxidative stability and flavour property of Sachima during the storage were studied. DPM hydrolysate-glucose syrup was heated at 120°C for different time. With the heating time increasing, browning and intermediate products increased, free amino group content decreased. MRPs heating for 60 min had the best antioxidant properties, evaluated by 2,2-diphenyl-1-picrylhydrazyl radical-scavenging activity, oxygen radical absorbance capacity and inhibition of linoleic acid autoxidation. Sachima added with 1% MRPs showed significantly (p < 0.05) lower acidity values and peroxide values than that without MRPs during 5 months storage. Results from GC-MS indicated that MRPs improved the flavour of Sachima. Based on these findings, MRPs derived from DPM hydrolysate-glucose syrup might be used in food lipids stabilization as potent natural antioxidant and flavour enhancer.

Antioxidant properties and radical-scavenging activity of ethanol extract of defatted peanut meal

Antioxidant properties and radical-scavenging activity of ethanol extract of defatted peanut meal

ANTIOXIDANT ACTIVITY OF PEANUT FLOUR FERMENTED WITH LACTIC ACID BACTERIA

Peanut flour (PF) was fermented with four strains of lactic acid bacteria. The effect of fermentation on the antioxidant activities (α,α-diphenyl-β-picrylhydrazyl [DPPH] radical-scavenging activity, reducing power and Fe2+ chelating activity) and antioxidant compounds (phenolic acids and flavonoids) was investigated. Depending on the starter organisms used, lactic acid fermentation could increase the DPPH scavenging activity, reducing power and Fe2+ chelating activity of PF. The content of phenolic acids had a significant decrease (P < 0.05) after fermentation. Meanwhile, a significant bioconversion (P < 0.05) of rutin into quercetin was observed after fermentation. There was a good linear correlation between the EC50 value of DPPH scavenging activity (R2 = 0.8893, P < 0.05) or reducing power (R2 = 0.8893, P < 0.05) and the concentration of quercetin in PF. These results indicated that lactic acid fermentation might be a good process to obtain functional PF with high antioxidant activity. PRACTICAL APPLICATIONS In the present study, the antioxidant activity of peanut flour (PF) was increased after lactic acid fermentation. Meanwhile, some bioactive compounds might be produced during the fermentation. The fermented products can be taken as a nutritional supplement for the elders, infants, pregnant women and individuals with malnutrition. More important, the inexpensive fermented products can be used as a good protein source in many developing countries where protein deficiencies remain a major health problem, especially for children. In addition, the fermented PF with higher nutritional value could be developed from defatted peanut meal, which is an inexpensive by-product of peanut oil production. For these reasons, this study provides a simple and effective strategy for improving the nutritional value of PF.

Nutritional and functional characteristics of gingerbread plum (&lt;i&gt;Neocarya macrophylla&lt;/i&gt;): an underutilized oilseed

The In-vitro protein digestibility, protein nutritional quality and functional characteristics (protein solubility, water/oil binding capacity, emulsifying capacity and foaming capacity) of gingerbread plum and peanut seed flour were studied. Among the nutritional parameters, the proportion of essential amino acids to total amino acids (E/T), amino acid scores (AAS) and protein efficiency ratio (PER) were studied. Defatted gingerbread plum seed meal (DGPSM) showed a high nutritional quality with PER and AAS values of 2.35 and 65.53 respectively. The solubility profile of DGPSM was similar to that of defatted peanut meal (DPM), with minimum solubility observed at pH 4 and maximum solubility at pH 10 and higher. Water and oil holding capacities were 3.01 and 3.12; 2.96 and 3.11 g/g for DGPSM and DPM respectively. DGPSM showed good foaming capacity (145 mL /100 mL) and stability (110 mL /100 mL) even after 60 min at room temperature. The emulsifying capacity of DGPSM was 29%. Bulk densities were 0.30 and 0.28 g/mL for DGPSM and DPM respectively. Finally, DGPSM was easily hydrolyzed by trypsin in vitro. These results show that DGPSM has functional properties that may find applications in the food industry.

Comparison of hydrolysis characteristics on defatted peanut meal proteins between a protease extract from Aspergillus oryzae and commercial proteases

A crude protease extract (CPE) was prepared from Aspergillus oryzae HN 3.042 in this work. Three commercial proteases (Alcalase 2.4L, Protamex and papain) and CPE were employed to hydrolyse defatted peanut meal (DPM). CPE was found to be the most effective protease with protein recovery of 80.6%. Moreover, CPE produced a higher degree of hydrolysis (DH, 43.4%) than the tested commercial proteases. The test of molecular weight distribution indicated that DPM proteins were mainly consisted of>10KDa fraction (86.6%), whereas 3–6KDa fraction was observed to be the main fraction of all the hydrolysates. CPE hydrolysate possessed a higher nutritional quality than DPM and other hydrolysates on the basis of FAO/WHO (1991) reference pattern. The sensory taste evaluation showed that CPE hydrolysate had better taste than other hydrolysates.

Emulsifying properties of the transglutaminase-treated crosslinked product between peanut protein and fish (Decapterus maruadsi) protein hydrolysates

Defatted peanut meal, a protein-rich by-product from the oil extraction industry, is underutilised owing to its inferior functional properties. In this study, transglutaminase (TGase) crosslinking and proteolysis were used to improve the emulsifying properties of peanut protein isolate (PPI) extracted from the meal. PPI and PPI hydrolysate (PPIH) were conjugated separately with fish (Decapterus maruadsi) protein hydrolysate (DPH), catalysed by TGase to obtain improvements in the emulsifying properties. Analyses by electrophoresis and high-performance liquid chromatography indicated that polymers were formed in all TGase-treated samples. In emulsions of PPIH, PPI-DPH and PPIH-DPH the volume/surface average particle diameter (d(32) ), creaming and instability phenomenon were decreased and the zeta-potential was increased after TGase treatment, showing improved emulsifying activity and emulsion stability. In the case of PPI, TGase treatment had no effect on the emulsifying activity, but the emulsion stability of TGase-treated PPI was improved. The study showed that TGase crosslinking and proteolysis could improve the emulsifying properties of PPI, while proteolysis followed by TGase crosslinking proved more efficient. The emulsifying properties of the heterologous protein systems of PPI-DPH and PPIH-DPH were also improved by TGase treatment.

Quality of Cooked Ground Beef Extended with Defatted Peanut Meal1

Abstract Beef chuck and plate cuts obtained from U.S.D.A. utility grade carcass were mixed and ground through a 0.318 cm plate. The ground meat was extended with extruded and non-extruded defatted peanut meal. Hydrated defatted peanut meal was added at the rate of 20 and 30 parts to 80 and 70 parts of the ground meat, respectively. All treatments were formulated to contain 20% fat in the final patty and loaf products. Extruded and non-extruded meat products were stored at −18 C for periods up to 6 weeks. All quality evaluations were conducted on cooked meat products. Ground meat patties and loaves extended with non-extruded peanut meal exhibited similar cooking losses to those either extended with extruded peanut meal or 100% beef products. Control meat products stored for 4 weeks or longer required larger forces to shear than the non-stored patties. Freezing storage of the extended meat products did not result in a change of shearing forces. These forces were similar to the shearing force exhibited by freshly prepared products. Trained sensory panelists indicated that extended meat patties were more tender and less cohesive than non-extended patties. However, sensory acceptability tests indicated similar acceptability ratings for the extended and non-extended meat patties and loaves.

Identification of Cultivar Differences in Seed Polypeptide Composition of Peanuts (Arachis hypogaea L.) by Two-Dimensional Polyacrylamide Gel Electrophoresis

Seed polypeptides from several cultivars of peanut (Arachis hypogaea L.) have been compared by means of a two-dimensional polyacrylamide gel electrophoresis. Protein was extracted from the defatted peanut meal by homogenizing in 5 millimolar K(2)CO(3)-9.5 molar urea. After addition of Nonidet P-40 (2%, v/v) and dithiothreitol (0.5%, w/v) the solution was centrifuged at 25,000 g. This procedure led to solubilization of more than 95% of the total protein. The clear supernatant fraction was then subjected to two-dimensional polyacrylamide gel electrophoresis, employing isoelectric focusing in the first dimension and electrophoresis in presence of sodium dodecyl sulfate in the second. After examining several cultivars, it was possible to construct a composite map to include all of the polypeptide species found among all of the cultivars examined. At least 74 major and between 100 and 125 minor components were detectable by Coomassie blue staining. The majority of these had isoelectric points between pH 4.4 and 8.0, and molecular weights between 16,000 and 75,000. Several different cultivars have been compared using this method and it has been shown that considerable variation exists among the major polypeptides present. The method should prove valuable for analyzing different genotypes and selecting varieties with a particular storage protein make-up, as well as for following compositional changes that occur during seed development and germination.

Production of ochratoxins A and B on country cured ham.

Two strains of Aspergillus ochraceus and six of Penicillium viridicatum isolated from country cured hams were screened for production of ochratoxins A and B. None of the isolated P. viridicatum strains yielded detectable amounts of ochratoxin A or B, whereas both strains of A. ochraceus produced ochratoxins A and B on rice, defatted peanut meal, and country cured ham. After 21 days of incubation on ham, one-third of the toxin was found in the mycelial mat on the ham surface, whereas two-thirds had penetrated into the meat to a distance of 0.5 cm.

Production of Ochratoxins A and B on Country Cured Ham

Two strains of Aspergillus ochraceus and six of Penicillium viridicatum isolated from country cured hams were screened for production of ochratoxins A and B. None of the isolated P. viridicatum strains yielded detectable amounts of ochratoxin A or B, whereas both strains of A. ochraceus produced ochratoxins A and B on rice, defatted peanut meal, and country cured ham. After 21 days of incubation on ham, one-third of the toxin was found in the mycelial mat on the ham surface, whereas two-thirds had penetrated into the meat to a distance of 0.5 cm.