Extracting Tenebrio molitor protein while preventing browning: effect of pH and NaCl on protein yield

2017 ◽  
Vol 3 (1) ◽  
pp. 21-31 ◽  
Author(s):  
L. Yi ◽  
M.A.J.S. Van Boekel ◽  
C.M.M. Lakemond

The potential of insects as an alternative protein source for food applications was investigated by studying the effect of pH and NaCl on extraction yield of water-soluble proteins from Tenebrio molitor, while preventing browning due to polyphenol oxidation. Minimum protein solubility (29.6%) was at pH=4-6 and maximum (68.6%) at pH=11. Protein extraction at 0.1 M NaCl, pH=10 gave a recovery of 100%. The observed increase in browning at pH=8-11 corresponded to a lower monomeric phenol content. Sodium bisulphite (studied from 0.5-4%) could prevent browning, whereas ascorbic acid (studied in the range 0.01-0.04%) could not prevent as strong as sodium bisulphite. After acid precipitation (pH=4) an isolate with a protein content of 74% (yield of 22% of total protein) was obtained. It was observed that proteins from T. molitor behave more or less the same as proteins from meat and fish with respect to aqueous extraction, which is of relevance for food industry when using T. molitor protein as an ingredient in food products.

Foods ◽  
2019 ◽  
Vol 8 (11) ◽  
pp. 572 ◽  
Author(s):  
Laroche ◽  
Perreault ◽  
Marciniak ◽  
Gravel ◽  
Chamberland ◽  
...  

Edible insects represent an interesting alternative source of protein for human consumption but the main hurdle facing the edible insect sector is low consumer acceptance. However, increased acceptance is anticipated when insects are incorporated as a processed ingredient, such as protein-rich powder, rather than presented whole. To produce edible insect fractions with high protein content, a defatting step is necessary. This study investigated the effects of six defatting methods (conventional solvents, three-phase partitioning, and supercritical CO2) on lipid extraction yield, fatty profiles, and protein extraction and purification of house cricket (Acheta domesticus) and mealworm (Tenebrio molitor) meals. Ethanol increased the lipid extraction yield (22.7%–28.8%), irrespective of the insect meal used or the extraction method applied. Supercritical CO2 gave similar lipid extraction yields as conventional methods for Tenebrio molitor (T. molitor) (22.1%) but was less efficient for Acheta domesticus (A. domesticus) (11.9%). The protein extraction yield ranged from 12.4% to 38.9% for A. domesticus, and from 11.9% to 39.3% for T. molitor, whereas purification rates ranged from 58.3% to 78.5% for A. domesticus and from 48.7% to 75.4% for T. molitor.


2019 ◽  
Vol 15 (7) ◽  
Author(s):  
Melih Güzel ◽  
Mehtap Çelik ◽  
Metin Yildirim

AbstractThe aims of this research were to examine the effect of pH on extraction of proteins from mahaleb (Prunus mahaleb L.) kernels, and to investigate the functional properties of resulting protein concentrate. The optimum pH values for the protein extraction and precipitation were determined as 10.0 and 4.5, respectively. The protein concentrate containing 92.73% dry matter, 6.29% ash, 6.02% carbohydrate, 1.42% fat and 73.11% protein was produced by using these extraction and precipitation pH values. Water-holding capacity, oil-holding capacity and the least gelling concentration of the protein concentrate were 2.81 g water/g, 1.66 g oil/g and 12%, respectively. Moreover, emulsifying activity and stability indices, foaming capacity and stability of protein concentrate were 27.21 m2/g, 81.05 min, 43.75% and 71.33% (after 30 min), respectively. The functional and chemical properties of the protein concentrate indicate that it may find application as functional ingredient for various food products.


1987 ◽  
Vol 50 (8) ◽  
pp. 681-684 ◽  
Author(s):  
CARL E. DAVIS ◽  
B. G. LYON ◽  
J. O. REAGAN ◽  
W. E. TOWNSEND

Protein solubility loss as a result of heat denaturation/coaguiation was followed by a ratio of extractable biuret positive compounds (EBPR). Extracts of water-soluble proteins were evaluated by isoelectric focusing (IEF) on polyacrylamide gels. Four heat treatments (60°C, 62.8°C, 65.6°C and 68.8°C) were employed in processing canned (No. 300×407) cured pork. Center cores from canned samples were ground for water soluble protein extraction utilizing a 1:3.3 meat-to-water ratio by high-speed blending (Sorvall Omni-mixer) for 1 min at 0–2°C, centrifuging 10 min at 27,000 ×g at 0–2°C and filtering (0.45–μa.m) with vacuum assist. Eight ml of the clear extract was re-heated in a glass tube for 15 min at 70°C, removed, and chilled (0–2°C) immediately. Coagulum was removed by filtration. EBPR was calculated from mg of protein/ml of initial muscle extract divided by mg of protein/ml of reheated extract for each temperature treatment. EBPR values were 1.75, 1.24, 1.13, and 1.10, respectively. Using 70°C as the critical temperature, an upper 95% confidence limit EBPR value of 1.12 was calculated. Portions of protein extract were isoelectrofocused on thin layer (0.8 mm) low concentration (5% monomer) polyacrylamide gels (pH gradient 3–10). IEF gels generally showed resolution of 12 to 23 protein bands in the muscle extracts, depending upon temperature treatment. Certain bands with apparent isoelectric points (pis) ranging from 7.4 to 8.5 decreased in staining intensity (silver stain) as temperature increased. The general protein separation profiles correlated with decreasing EBPR values as temperature increased.


2013 ◽  
Vol 33 (6) ◽  
pp. 1223-1233 ◽  
Author(s):  
Priscila F. Coldebella ◽  
Simone D. Gomes ◽  
Janete A. Evarini ◽  
Marney P. Cereda ◽  
Sílvia R. M. Coelho ◽  
...  

The cassava leaf, waste generated in the harvest of the roots, is characterized by high content of protein, vitamins and minerals; however, its use is limited due to the high fiber content and antinutritional substances, which can be removed by obtaining protein concentrates. In this context, the objective of this study was to evaluate protein extraction processes, aiming the use of cassava leaves (Manihot esculenta Crantz) as an alternative protein. Four methods were tested: 1) Coagulation of Proteins by Lowering the Temperature, 2) Extraction by Isoelectric Precipitation, 3) Solubilization of Proteins and 4) Fermentation of Filter Leaf Juice. To obtain the concentrates, the use of fresh or dried leaves and extraction in one or two steps were also evaluated. The solubilization of proteins (method 3) showed a higher extraction yield; however, with concentrate of low quality. The fermentation of the juice (method 4) produced concentrates with higher quality and lower costs and the isoelectric precipitation (method 2) promoted the obtention of concentrates in less time, both with good prospects for use. The use of two extraction steps was not advantageous to the process and there was no difference between the use of fresh or dried leaf, and the use of fresh leaves is presented as a good option for the simplicity of the method.


2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Elisabetta De Angelis ◽  
Simona Lucia Bavaro ◽  
Linda Monaci ◽  
Rosa Pilolli

Several buffer compositions were compared for their efficiency in protein extraction from both raw and roasted peanut and hazelnut samples, the final goal being to understand the modification of protein solubility upon roasting and maximize the extraction yield. Denaturant conditions provided by urea-TBS buffer resulted in satisfactory extraction yields for both peanut and hazelnut samples, before and after the thermal treatment. In addition, different varieties of peanuts and hazelnuts were characterized to highlight the extent of variability in the protein profile accounted by the varietal factor and eventual differential resistance among cultivars to protein modification induced by the thermal processing. The protein profile was characterized by gel electrophoresis, and specific bands were analyzed by micro-HPLC-MS/MS coupled to software-based protein identification. No significant difference was observed for the investigated hazelnut cultivars, namely, Campana, Romana, and Georgia, whereas interesting features were presented for the peanut varieties Virginia, Zambia, and China. In particular, Zambia variety lacked two bands of approximately 36 and 24 kDa that were visible in Virginia and China varieties, which could suggest a lower allergenic potential of this particular variety which deserves to be further investigated before drawing final conclusions.


2000 ◽  
Vol 6 (3) ◽  
pp. 197-205 ◽  
Author(s):  
T. Jimenez ◽  
M.A. Martinez-Anaya

Water soluble pentosans (WSP) from doughs and breads made with different enzyme preparations are characterized according to extraction yield, sugar composition, xylose/arabinose ratio and molecular weight (MW) distribution. Extraction yield was greater for dough than for bread samples, ranging from 0.94 to 1.64%, but bread extracts had a higher purity. Percent of pentoses in purified WSP was greater in pentosanase supplemented samples (28-55%) than in control and amylase containing samples (23-32%). Major sugars were xylose and arabinose, but glucose and mannose also appeared in the extracts. The xylose/arabinose (Xyl/Ara) ratio was 1.3-1.6 and underwent small changes during processing. Enzyme addition caused an increase in Xyl/Ara ratio, attributable to a debranching of arabinoxylans (AX) with higher degree of Ara substitution by arabinofuranosidase. Addition of pentosanases had a significant effect in increasing WSP with MW over 39 000, whereas those of low MW changed only slightly. MW distribution depended on enzyme source, and whereas some enzymes showed activity during fermentation others increased their activity during baking. No synergistic effects were observed in studied variables due to the combination of amylases with pentosanases. Protein in WSP extracts eluted together with ferulic acid suggesting they were linked, but not associated with a determined carbohydrate fraction.


2011 ◽  
Vol 138-139 ◽  
pp. 933-936 ◽  
Author(s):  
Xuan Chen ◽  
Hong Yu Luo ◽  
Jun Yu ◽  
Peng Xiang Yue ◽  
Lin Zhou ◽  
...  

Alcohol-alkali method and base digestion method were investigated to extract proteins from tea residues, respectively. According to single factorial experiments, results showed that the optimal extraction technology of alcohol-alkali method were pH 12, temperature of 80 °C, ethanol concentration of 60%, liquid-solid ratio of 40, 60 min, and the protein extraction rate reached 15.0%. And the optimal extract conditions of base digestion were pH 12, temperature of 80 °C, liquid-solid ratio of 50, 80 min, which made the protein yield reached 31.5%. Furthermore, alcohol-alkali method was more beneficial to protein extraction from tea residues under lower temperature and weak alkali condition (40-60 °C, pH 8-10). While base digestion had higher extraction yield under high temperature and strong alkali condition (60-80 °C, pH 11-12).


2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Malek Ennaifer ◽  
Taroub Bouzaiene ◽  
Moncef Chouaibi ◽  
Moktar Hamdi

Background. The decoction of Pelargonium graveolens yields an antioxidant-rich extract and a water-soluble polysaccharide. This study aims (1) to investigate the effect of process parameters (extraction time and temperature) on the antioxidant activity of the decoction and the extraction yield of CPGP by response methodology and (2) to study the chemical properties of the optimized decoction and rheological properties of the corresponding extracted polysaccharide. Results. The antioxidant-rich decoction contained about 19.76 ± 0.41 mg RE/g DM of flavonoids and 5.31 ± 0.56 mg CE/gDM of condensed tannins. The crude Pelargonium graveolens polysaccharide (CPGP) contained 87.27 % of sugar. Furthermore, the CPGP solutions (0.5%, 1%, and 2%) exhibited shear-thinning or pseudoplastic flow behavior. A central composite design (CDD) was applied to assess the effects of temperature and time on the antioxidant activity of the decoction, on the one hand, and on water-soluble polysaccharide yield, on the other. The decoction optimization of Pelargonium graveolens aimed to use less energy (93°C for 11 minutes) leading to the highest values of decoction phenolic content (33.01 ±0.49 mg GAE/gDM) and DPPH scavenging activity (136.10 ± 0.62 mg TXE/gDM) and the highest values of CPGP yield (6.97%). Conclusion. The obtained results suggest that the CPGP rheological characteristics are suitable for applications in many industries, especially food. The values of optimal conditions showed that Pelargonium graveolens decoction operation could have multiple uses, especially for consuming less energy.


2021 ◽  
Author(s):  
Ruby R. Rafanan

Emulsified microemulsions (EMEs), first described in detail in 2005 by the group of Garti, consist of a thermodynamically stable water-in-oil microemulsion phase (w1/o) further dispersed within an aqueous continuous phase (w2). These internally-structured w1/o/w2 dispersions are promising controlled release vehicles for water-soluble flavouring compounds, drugs and nutraceuticals. With a stable internal droplet structure, storage stability is improved over non-thermodynamically stable structured emulsions and may exhibit unique controlled release behaviour. Use of food-grade components allows for wider and safer applications in food and pharmaceutical products. In this thesis, a food-grade w1/o microemulsion consisting of glycerol monooleate, tricaprylin and water was dispersed in an aqueous (w2) phase by membrane emulsification and stabilized by a caseinate-pectin complex to produce w1/o/w2 EMEs. The resulting EME showed no signs of phase separation for weeks at room temperature. The microemulsion and EME were characterized by differential scanning calorimetry (DSC), cryo-TEM and small angle x-ray scattering (SAXS) to determine whether the microemulsion’s internal structure was maintained after emulsification. It was shown that EME droplets displayed ordering around the periphery consistent with some loss of microemulsion structure, but maintained the characteristic disordered microemulsion structure at the droplet core. Overall, this research demonstrated the feasibility of developing EME for possible applications in food and non-food applications.


2021 ◽  
Author(s):  
Ruby R. Rafanan

Emulsified microemulsions (EMEs), first described in detail in 2005 by the group of Garti, consist of a thermodynamically stable water-in-oil microemulsion phase (w1/o) further dispersed within an aqueous continuous phase (w2). These internally-structured w1/o/w2 dispersions are promising controlled release vehicles for water-soluble flavouring compounds, drugs and nutraceuticals. With a stable internal droplet structure, storage stability is improved over non-thermodynamically stable structured emulsions and may exhibit unique controlled release behaviour. Use of food-grade components allows for wider and safer applications in food and pharmaceutical products. In this thesis, a food-grade w1/o microemulsion consisting of glycerol monooleate, tricaprylin and water was dispersed in an aqueous (w2) phase by membrane emulsification and stabilized by a caseinate-pectin complex to produce w1/o/w2 EMEs. The resulting EME showed no signs of phase separation for weeks at room temperature. The microemulsion and EME were characterized by differential scanning calorimetry (DSC), cryo-TEM and small angle x-ray scattering (SAXS) to determine whether the microemulsion’s internal structure was maintained after emulsification. It was shown that EME droplets displayed ordering around the periphery consistent with some loss of microemulsion structure, but maintained the characteristic disordered microemulsion structure at the droplet core. Overall, this research demonstrated the feasibility of developing EME for possible applications in food and non-food applications.


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