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May 2013, Vol. 7, No. 5, pp. 547-552
Journal of Life Sciences, ISSN 1934-7391, USA
Lipids Data Composition of Edible Ant Eggs
Liometopum apiculatum M. Escamoles
Melo Ruiz Virginia1, Sánchez Herrera Karina1, Sandoval Trujillo Horacio1, Quirino Barreda Tomás1 and Calvo
Carrillo Concepción2
1. Departamento de Sistemas Biológicos, Universidad Autónoma Metropolitana Unidad Xochimilco, D. F., C.P. 04960, México
2. Departamento de Nutrición Animal, Instituto Nacional de Ciencias Médicas y Nutrición Salv
a
dor Zubiran, D.F. C.P. 14000, México
Received: April 19, 2013 / Accepted: April 25, 2013 / Published: May 30, 2013.
Abstract: Escamoles ant eggs of Liometopum apiculatum M., specie of edible insects, reproduced under the ground in desert regions
nearby cactus plants at spring season, are high demand in Mexico by sensory characteristics of flavor and texture, and consumed as
cultural tradition by different social groups, in rural communities and in luxury restaurants of urban cities. Insects source of macro
and micronutrients were collected in Mexico State in April 2006 to be studied and analyze samples to generate composition data. Fat
of dry insects was extracted in a Soxhlet equipment; iodine value was examined by the Hannus method to determine degree of
unsaturation; saponification value with chemical method to separate non-saponificable fats. Saponificable lipids were determined by
gas chromatography apparatus to define the fatty acids profile. Data show: total lipids 32.17%, linoleic 67.66%, linolenic 2.61% and
arachidonic 0.16% acids of the saponificable fraction. Escamoles to be consumed up to three months after collection should be
storage refrigerated, for longer intake frozen. Because of high content of linoleic C18:2w6, low of linolenic C18:3w3,
eicosapentanoic C20:5w3 and arachidonic acid C20:4w6, natural in escamoles, they present high stability. In conclusion escamoles
could be an important source of fatty acids for human health.
Key words: Escamoles ant eggs, fatty acids, human health.
1. Introduction
Entomography is traditional in Mexico since
ancient times, escamoles ant eggs of the Formicidae
family are part of the cultural diet in rural
communities and at urban restaurants, consider as
delicacies in Mexico. Some other countries of Latin
America, Asia and Australian ant eggs are appreciated
as well by their delicate flavor [1], insects are
reproduced at desert regions at an altitude range from
1,800 to 3,000 m above sea level in underground nests
depth 1 to 1.5 m, to keep low humidity and warm
environment for natural develop of eggs. Nests are at
xerophyte thicket environment, nearby maguey agave
sp or nopal opuntia sp cactus, as source of food sugars,
amino acids and minerals [2, 3]. Ants maintain a
Corresponding author: Melo Ruiz Virginia, Ph.D.,
research fields: chemistry, food science and entomology.
E-mail: vmelo@correo.xoc.uam.mx.
relationship with their habitat diversity and preserve
equilibrium of the ecology where they leave [4]. Ant
eggs provide a good amount of macronutrients such as
fatty acids linoleic C18:2w6, linolenic C18:3w3,
arachidonic 20:5w3, C20:4w6 and EPA
(eicosapentanoic acid) 20:5w3.
Fatty acids long chain w3 and w6 PUFA
(polyunsaturated fatty acids) are essential in human
nutrition, for normal growth, development and
optimal function of brain, heart and other systems [5].
There is plenty scientific evidence which clearly proof
that dietary FA (fatty acids) are involved in the
etiology of many diseases, therefore, their
consumption is important in health and disease
prevention. FA classically viewed as an energy
substrate, PUFA data composition suggests that w3
FA and EPA (20:5w3) may play a protective role in
coronary artery disease and its complication including
DAVID PUBLISHING
D
Lipids Data Composition of Edible Ant Eggs Liometopum apiculatum M. Escamoles
548
the control of the levels of blood lipids, blood pressure,
cardiac and vascular function and coagulation. [6, 7],
another important function of PUFA w3 is the study
that has demonstrated the critical role for maintenance
of normal brain function in adults, and for growth and
functional development of the brain in infants [1].
PUFA are synthesized mainly by uni- and
multicellular marine phytoplankton and algae, the
PUFA so obtained are transferred and incorporated
into lipids of marine species through the food chain.
Therefore, seafood and shellfish are considered as a
good source of w3FA; however, those sources of
PUFA are not available to all social groups. Even
though there are other sources of these lipids, they
need to be explored in order to inform population the
nutraceutical benefits their consumption provide to
human health.
Poor nutrition is a problem worldwide and is
getting worse every day [8]. The natural sources of
food available are often less considered, whereas
research of new technologies for synthesis and
conservation, raises prices and make the products
inaccessible to the majority of population, particularly
social groups from rural communities and slums in
urban cities. Poor nutrition affects an individual’s
performance makes him/her vulnerable to different
chronic degenerative diseases [9-11]. The aim of this
study is to strengthen analytical performance of
Escamoles samples to generate composition data of
lipids, and promote their consumption among all
social groups.
2. Materials and Methods
2.1 Sample Collection and Preparation
The collection of samples from convenient
accessible points [12] at xerophyte thicket
environment nearby agave spp cactus was performed
at middle March and middle April, 2006. Edible ant
eggs Liometopum apiculatum M. Escamoles were
harvested in Milpa Alta, Mexico, D.F. and three
samples were collected each time. Material was
washed with fresh water and dried over tower paper,
stored in a glass container at -4 °C and transported to
laboratory for further analysis.
2.2 Determination of Moisture Content
Moisture content of sample was determined using
the direct drying method. Homogenized sample (10 g)
was dried in an oven at 60 °C for 24 h. The samples
were powdered in a mortar then passed through the 60
mesh size. The fine powder so obtained was used for
further analysis.
2.3 Determination of Lipid Content
Lipid content determination was carried out by the
semicontinuous solvent extraction method AOAC
Method 934.01 [13] as follows: 10 g of the sample was
extracted with 180 mL petroleum ether on a Soxhlet
apparatus for 10 h. Petroleum ether was removed by
evaporation and the residue of lipid was weighed. All
samples were analyzed in triplicate and the results are
expressed as g/100g dry basis of sample.
2.4 Determination of Protein Content
Protein content of sample was determined
according to the principle of Kjeldahl method (AOAC
Method 945.01 [14]). Sample (1 g) was digested with
15 mL concentrated sulphuric acid using electrically
heated aluminum block digester. Resulting digest was
diluted and then made alkaline with 50 mL 40%
sodium hydroxide. This was followed by rapid steam
distillation of ammonia from the diluted digest into 25
mL 4% boric acid for manual titration with 0.2 N
hydrochloric acid. A conversion factor of 6.25 was
used to convert the measured nitrogen content to
protein content. All samples were analyzed in
triplicate and the results are expressed as g/100g dry
basis of sample.
2.5 Determination of Total Available Carbohydrate
Content
Total available carbohydrate content of sample was
determined by the Clegg-anthrone method [15].
Lipids Data Composition of Edible Ant Eggs Liometopum apiculatum M. Escamoles
549
Sample (1 g) was digested with 13 mL 52% perchloric
acid to hydrolyze disaccharides, trisaccharides and
higher oligomers to their component reducing sugars
and reacted with anthrone reagent under acid
condition to produce a blue/green color. Anthrone
reagent was prepared by dissolving 0.1% (w/v)
anthrone in diluted sulphuric acid (sulphuric
acid:water in ratio of 2.3:1.0, v/v). An aliquot (1 mL)
of appropriately diluted hydrolysate was mixed with 5
mL anthrone reagent. Absorbance of the reaction
mixture was measured at 630 nm against a blank after
incubated in boiling water for 12 min and cooled. All
samples were analyzed in triplicate. Glucose (0-100
mg/L) was used to construct a standard curve for
quantification and the results are expressed as g/100g
dry basis of sample.
2.6 Determination of Iodine Value (Hannus Method)
Iodine value determination was performed
according to the Hannus method AOCS Method
920.158 [14], as follows weigh accurately about 0.1 g
of oil into a 500 mL stoppered conical flask. Dissolve
oil in 10 mL chloroform. Add 25 mL Hannus iodine
solution from bulb pipette. Keep in the dark for 30
min, shaking occasionally. Add 10 mL 15% potassium
iodine and 100 mL water (washing down any free
iodine on stopper). Titrate with 0.1 N Na2S2O3, using
1% starch solution as indicator. (Note: toward end of
titration, stopper bottle and shake vigorously, so that
any iodine remaining in solution in CHCl3 may be
taken up by KI solution). Conduct two blank
determinations along with determination on sample.
2.7 Determination of Saponification Value
Saponification value determination was performed
according to method AOCS Method 920.160; AOCS
Method [14] Cd 3-25 as follows; weigh into the flask
about 2 g of oil to within 0.001 g and add exactly 25
mL of 0.5 N ethanolic KOH solutions. Attach the
flask to the condenser. Boil gently, mixing from time
to time. After 60 min, stop heating. (Note: For certain
fats which are difficult to saponify, it is necessary to
heat for longer than 60 min). Add 4 to 5 drops of
phenolphthalein solution. Titrate the hot soap solution
with the 0.5 N hydrochloric acid solutions. Carry out a
reagent blank test on the ethanolic potassium
hydroxide solution.
2.8 Determination of the FA Composition
Dry whole organisms (up to 50 mg) were placed in
a suitable glass reaction vessel closed with a screw
cap, incorporating an inert polytetrafluoroethylene
seal. A mixture (3 mL) of dry
methanol-toluene-sulphuric acid (30:15:1) was added
and closed vessel kept at 75° in an oven or heating
block overnight (16-18 h). After cooling to room
temperature, 2 mL of light petroleum (b.p. 60-80°)
was added; the mixture was shaken and centrifuged
for 10 min at low speed. A small column (ca. 1 cm) of
ammonium hydrogen carbonate was prepared dry in a
short-form cotton wool-plugged Pasteur pipette,
prewashed with diethyl ether (2 mL), the upper light
petroleum layer pipette on and the eluent collected in
a small vial suitable for subsequent storage. A further
portion (1 mL) of light petroleum was added to the
remaining reaction mixture and after shaking and
centrifugation the upper layer added to the column.
The pipette used for the transfer was placed in the
column and the combination washed with diethyl
ether (1 mL). The combined eluents were evaporated
in a stream of nitrogen at < 40° [16]. FAME (Fatty
acid methyl esters) were separated by gas
chromatography on DB-5 Phenysilicone capillary
column (50 m by 0.5 mm [inside diameter]) installed
in the model GC-CP3380 Varian gas chromatograph,
with a 1079 injector and autoinjector model CP-8400
by using He as the carrier gas at a linear velocity of 1
mL/min and a temperature of 170 °C. Equipped with a
flame ionization detector, at an initial oven
temperature of 150 °C/0.5 min was kept, during the
injection then a temperature program raised to 220 °C
to 10 °C/min began and continued increasing
Lipids Data Composition of Edible Ant Eggs Liometopum apiculatum M. Escamoles
550
4 °C/min until reached 236 °C, that it was kept for 2.5
min, then raised again to a final oven temperature of
291 °C of 5 °C/min. The injection port and detector
temperatures were set at 300 °C. A 1-µL injection was
made, using a split ratio 100:1. The sample
determination was carried out by triplicate.
3. Results and Discussion
3.1 Moisture, Saponification, Lipid and Iodine Value
and Macronutrients Composition
The weights of edible ant eggs Liometopum
apiculatum M. Escamoles before and after moisture
test were measured. Table 1 presents data obtained
was 48.88% of dry matter and 51.12% of water.
Saponification was carried out in order to determine
the presence of fatty acids able of saponification, as
well as the iodine value to investigate the presence of
polyunsaturated fatty acids present on the samples, to
find out if results were positive proceed with the
analysis. Total lipids for the sample were 32.17%,
with polyunsaturated and saponificable fatty acids.
The protein contents of edible ant eggs Liometopum
apiculatum M. Escamoles determined was 42.25%;
lipids 32.96%; minerals 7.85%; crude fiber 1.51% and
soluble carbohydrates 14.23% (Table 2).
3.2 Composition of FA in the Edible Ant Eggs
Liometopum apiculatum M. Escamoles
A total of four FA were identified from the edible
ant eggs Liometopum apiculatum M. Escamoles
showed in Table 3, which are PUFA Linoleic acid
18:2w6, Linolenic acid 18:3w3, Arachidonic acid
20:4w6 and Eicosapentanoic acid 20:5w3. Results of
the test revealed that 18:2w6 was the major FA with
67.66%, followed by 18:3w3 with 2.61%, and 20:4w6,
20:5w3 with 0.16% both. Among the PUFA, EPA
was determined with 0.16% that represents 0.5 g/100g
Table 1 Composition of dry and water of edible ant eggs
Liometopum apiculatum M. Escamoles (%).
Water content Dry sample
48.88% 51.12%
Table 2 Macronutrient composition of edible ant eggs
Liometopum apiculatum M. Escamoleson dry basis (%).
Proteins Lipids Minerals Crude
fiber Soluble
carbohydrates
42.25 32.96 7.85 1.51 14.23
Table 3 Fatty acids of edible ant eggs Liometopum
apiculatum M. Escamoles (%).
FA Composition (%)
C18:2w6 Linoleic acid 67.66
C18:3w3 Linolenic acid 2.61
C20:4w6 Arachidonic acid 0.16
C20:5w3 Eicosapentanoic acid 0.16
Table 4 Comparison of EPA in different food sources.
Source EPA (g/100g tissue)a, b
Edible ant eggs
L
iometopum
apiculatum M. Escamoles 0.5
Viscera of farmed Atlantic Salmon 1.64
Black sea bass 0.3
Carp 0.2
Red snapper 0.04
King mackerel 0.04
Snapper 0.05
Beef 0.02c
Turkey 0.03c
Eggs regular 0.08c
a [17]; b[18]; c[19].
tissue, no DHA (docosahexanoic acid) C22:6w3 was
found on these samples.
3.3 Comparison of EPA in Edible Ant Eggs
Liometopum apiculatum M. Escamoles with Other
Sources
Table 4 shows the most representative samples with
presence in EPA of some foodstuff. EPA in edible ant
eggs Liometopum apiculatum M. Escamoles in this
study was 0.5 g/100g tissue that represents the third
part compared to viscera of farmed salmon that has
1.64 g/100g tissue, that has higher amount of EPA than
other food from marine source as the black sea bass,
red snapper, snapper and other fishes. Chicken eggs,
beef and turkey staple regular consumed are also poor
sources of polyunsaturated fatty acids. Data show the
considerable amount of the EPA inedible ant eggs
Liometopum apiculatum M. Escamoles considering
that inset is not a marine source. Availability and
Lipids Data Composition of Edible Ant Eggs Liometopum apiculatum M. Escamoles
551
intake of these insects are easier and less expensive for
population. Marine products consumption in Mexico
are mainly by inhabitants of the coast but very poor to
other social groups, because are not easy to obtain, and
not available to everyone, farm products are well
distributed, and better accepted by tradition culture and
included in a daily diet, nevertheless that kind of food
have not, or a very low amount of EPA and FA in
general.
Intake of long chain w3 (Omega-3) PUFA,
particularly EPA (20:5w-3) and DHA (22:6w3) is
important in human nutrition, health and disease
prevention. EPA also lower serum triglyceride acids
and cholesterol levels, increase membrane fluidity,
and reduce thrombosis [18, 20, 21]. These PUFA are
found mainly in fish oil and fishmeal because they are
primarily marine-derived.
Many national health authorities and physicians
recommend and intake of around 500 mg/day for
healthy adults and more for those with known heart
conditions or an excess of fatty triglycerides in the
blood [19].
Omega-3 and Omega-6 fatty acids which represent
about one-third of the intracellular fatty acids can not
be synthesized by humans therefore must be essential
components of diet, thus the importance of this
findings is also edible ant eggs Liometopum
apiculatum M. Escamoles high C18:2w6 might
represent the basis for the synthesis of EPA and DHA
which is required for optimum development and
function of the nervous system [5].
4. Conclusions
Edible ant eggs Liometopum apiculatum M.
Escamoles are a good source of FA polyunsaturated
particularly of EPA, necessary in the human nutrition
for health, so its consumption could be an important
source of those fatty acids for human health and must
be promoted in order to obtain a better nutritional state
and prevent chronic degenerative diseases.
Escamoles ant eggs of Liometopum apiculatum M.
are consumed in Mexico since ancient times this
cultural tradition, remain up to date at either rural
communities as well as urban cities and should be
encourage in other countries.
References
[1] F.B. Hu, L. Bronner, W.C. Willet, M.J. Stampfer, K.M.
Rexrode, C.M. Albert, et al., Fish and omega-3 fatty acid
intake and risk of coronary heart disease in women,
JAMA 287 (2002) 1815-1821.
[2] V. Melo, Los insectos de Xochimilco alimento de alto
contenido en proteínas, II Congreso Internacional de
Química de la ANAQUE, España, 1992. (in Spain)
[3] A. Romo, Los escamoles (Liometopum apiculatum M.)
como una alternativa de alimentación e ingresos
económicos en el municipio de San Agustín Tlaxiaca,
Hidalgo, Thesis UACH, México, 1999. (in Spain)
[4] M.R. Speight, M.D. Hunter, A.D. Watt, Ecology of
Insects, Concepts and Applications, Blackwell Science,
1999, p. 169.
[5] I. Lenoir-Wijnkoop, Lipids from Alpha to Omega, John
Libbey, Eurotext, Paris, 1999.
[6] J.E. Kinsella, B. Lokesh, R.A. Stone, Dietary n-3
polyunsaturated fatty acids and emelioration of
cardiovascular disease: Possible mechanisms, Am J Clin
Nutr. 52 (1990) 1-28.
[7] T.A. Mori, L.J. Beilin, Long-chain omega 3 fatty acids,
blood lipids and cardiovascular risk reduction, Curr Opin
Lipidol. 12 (2001) 11-17.
[8] R.G. Ackman, Fatty acids, in: R.G. Ackman (Ed.),
Marine Biogenic Lipids, Fats and Oils, CRC Press, Boca
Raton, 1989, pp. 145-178.
[9] M. Windsor, S. Barlow, Introduction to Fishery
By-products, Fishing New Books, Farnham, United
Kingdom, 1981, pp. 1-189.
[10] R.G. Ackman, Nutritional composition of fats in
seafood’s, Prog Food Nutr Sci. 13 (1989) 161-289.
[11] J. Folch, M. Leed, G.H. Sloane Stanley, A simple method
for the isolation and purification of total lipids from
animal tissues, J Biol Chem 226 (1957) 497-509.
[12] H. Greenfield, D.A.T. Southgate, Food Composition Data,
2nd ed., FAO, Rome, 2003, pp. 63-82.
[13] Official Methods of Analysis, 15th ed., AOAC
(Association of Official Analytical Chemists),
Washington, DC, 1990.
[14] Official Methods and Recommended Practices of the
American Oil Chemists’ Society, 4th ed., 2nd printing
(additions and revisions through 1993), AOCS (American
Oil Chemists’ Society), Champaign, IL, 1990.
Lipids Data Composition of Edible Ant Eggs Liometopum apiculatum M. Escamoles
552
[15] Peris-Tortajada, Carbohydrates and starch, in: M.L.N.
Leo (Ed.), Handbook of Food Analysis: Physical
Characterization and Nutrient Analysis, Marcel-Dekker,
Inc., USA, 2004, p. 392.
[16] M.D. Collins, M. Goodfellow, D.E. Minnikin, Fatty acid
composition of some mycolic acid-containing
coryneform bacteria, J General Microbiol 128 (1982)
2503-2509.
[17] T. Sun, X. Xu, W. Prinyawiwatkul, FA composition of
the oil extracted from farmed atlantic salmon (Salmon
salar L.) viscera, JAOCS 83 (2006) 615-619.
[18] P.A. Simopoulos, Omega-3 fatty acids in health and
disease and in growth and development, Am J Clin Nutr
54 (1991) 438-463.
[19] International Fishmeal and Fish Oil Organization, A
guide to the long chain omeg-3 fatty acids,
eicosapentaenoic acid (EPA) and docosahexaenoic acid
(DHA) in fish oil, 2008,
http://www.iffo.net/downloads/77.pdf.
[20] L.A. Horrocks, Y.K. Yeo, Health benefits of
docosahexaenoic acid (DHA), Pharmacol Res 40 (1999)
211-225.
[21] P.A. Simopoulos, G.L. Cleland, Omega-6/Omega-3
Essential Fatty Acid Ratio: The Scientific Evidence
(World Review of Nutrition and Dietetics), Karger, Basel,
Switzerland, 2003.
... Table 1). This result is similar to that obtained by Melo-Ruíz et al. (2013a, 2013b, who reported a content of 42.25% of this nutrient in samples from Mexico City and 40.9% (g/100 g dry base) in samples from the state of Hidalgo; both samples were collected in xerophile scrub vegetation. Sandoval et al. (2010) found a protein content of 42.35% in samples from Actopan and 41.78% (g/100 g dry base) in samples from Zempoala, Hidalgo, collected in CS and DRS (INEGI, 2013). ...
... These percentages are the highest reported for the species (Table 1). For example, Melo et al. (2011;2013a) reported 33.96% and Sandoval et al. (2010) 34.26%. ...
... Crude fiber content (Table 1) was slightly higher in larvae from CS (1.4%) than in those from DRS (1.3%) and DMS (1.3%). These results are similar to those reported by Ramos-Elorduy et al. (2002) and Melo et al. (2011;2013a), who found 1.05%, 1.30%, and 1.51% of crude fiber, respectively. The lowest contents were found in larvae from Actopan (0.74%) and Zempoala (0.41%), Hidalgo (Sandoval et al., 2010). ...
Article
In Mexico the ant Liometopum apiculatum is an important insect nutritionally, economically and ecologically. Their larvae (“escamoles”) contain proteins, lipids, vitamins and minerals, the concentrations of which may be related with the type of vegetation where the ant forages. The objective of this study was to evaluate the content of macro and micro nutrients of L. apiculatum larvae collected in three types of vegetation in north-central Mexico. We determined content of moisture, crude protein, total lipids, crude fiber, ash, and nitrogen-free extract. The amino acids were analyzed by cationic Exchange chromatography with acid hydrolysis and fatty acids by gas chromatography and solvent extraction with sodium methoxide. The effect of vegetation type on nutrient content was determined with an ANOVA and Sheffé comparison of means (P <.05). The concentration of amino acids and fatty acids (FA) was analyzed with a Kruskall-Wallis test (P <.05). Significant differences were found in protein, lipids and ash (P <.0001) and moisture content (P <.0036). We identified 17 amino acids, which concentration differed by type of vegetation. There were no significant differences in fatty acids. It is likely that the differences in the concentrations of macronutrients are due to the diversity and differential density of the food components available in each type of vegetation for L. apiculatum, and that the number of types and quantity of amino acids and fatty acids depend on the chemical properties of the liquid secretions the ants obtain by trophobiosis.
... Table 1). This result is similar to that obtained by Melo-Ruíz et al. (2013a, 2013b, who reported a content of 42.25% of this nutrient in samples from Mexico City and 40.9% (g/100 g dry base) in samples from the state of Hidalgo; both samples were collected in xerophile scrub vegetation. Sandoval et al. (2010) found a protein content of 42.35% in samples from Actopan and 41.78% (g/100 g dry base) in samples from Zempoala, Hidalgo, collected in CS and DRS (INEGI, 2013). ...
... These percentages are the highest reported for the species (Table 1). For example, Melo et al. (2011;2013a) reported 33.96% and Sandoval et al. (2010) 34.26%. ...
... Crude fiber content (Table 1) was slightly higher in larvae from CS (1.4%) than in those from DRS (1.3%) and DMS (1.3%). These results are similar to those reported by Ramos-Elorduy et al. (2002) and Melo et al. (2011;2013a), who found 1.05%, 1.30%, and 1.51% of crude fiber, respectively. The lowest contents were found in larvae from Actopan (0.74%) and Zempoala (0.41%), Hidalgo (Sandoval et al., 2010). ...
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... They cannot, however, be stored for more than eight days at 4 ºC because decay will take place after that span or puncture of the walls; furthermore, loss of their natural juices during thawing has been observed in frozen escamoles at −18 ºC. From a nutritional point of view, escamoles consist of proteins, carbohydrates and lipids, as well as vitamins A, D, and E ( Melo-Ruiz et al., 2013b;Kouřimská and Adámková, 2016). It is important to note that in order to sustain the food supply for a growing global population, the United Nations has also promoted entomophagy-insect consumption ( Baker et al., 2016). ...
... They also contain oleic and linoleic acid and carbohydrates, such as trehalose, glucose and glucose polymers. It is important to point out that the percentages of protein and lipid contents measured in these escamoles are close to those previously reported by Melo-Ruiz et al. (2013a) and Melo-Ruiz et al. (2013b). Based on their chemical composition, escamoles could be considered a promising source of suitable nutrients for human consumption and also as a complex food system for thermal analysis. ...
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The objective of this research was to measure the freezing curve and the parameters of the maximally-freeze-concentrated phase of escamoles and to propose their use in preventing chemical and structural changes during frozen storage. Samples with freezable and unfreezable moisture were prepared and analyzed with differential scanning calorimetry (DSC), with which freezing points (Tm, T′m) and glass transition temperatures (Tg, Tg′) were determined. An average Tg value of 61.5 ± 6.4 ºC was found for anhydrous escamoles. Samples containing unfreezable water, however, showed no glass transition. The maximalfreeze-concentration condition was determined at the values of x′ s = 0.870 g solid/g sample, T′m =-22.7 °C and T′g = -30.7 °C. The stability of frozen escamoles was tested based on the application of their corresponding T0 g value. Therefore, escamoles were frozen at -20, -35 and -80 °C for four months, and quality parameters such as thawing loss, protein and lipid oxidation and structural changes in thawed escamoles were evaluated. Results (p < 0.05) showed that chemical and structural changes were mainly detected in samples stored at -20 °C. Thus, a storage temperature of -35 °C is recommended for the long-term stability of fresh escamoles. © 2018, Universidad Autonoma Metropolitana Iztapalapa. All rights reserved.
... They cannot, however, be stored for more than eight days at 4 ?C because decay will take place after that span or puncture of the walls; furthermore, loss of their natural juices during thawing has been observed in frozen escamoles at ?18 ?C. From a nutritional point of view, escamoles consist of proteins, carbohydrates and lipids, as well as vitamins A, D, and E ( Melo-Ruiz et al., 2013b;Kou?imsk? and Ad?mkov?, 2016). ...
... They also contain oleic and linoleic acid and carbohydrates, such as trehalose, glucose and glucose polymers. It is important to point out that the percentages of protein and lipid contents measured in these escamoles are close to those previously reported by Melo-Ruiz et al. (2013a) and Melo-Ruiz et al. (2013b). Based on their chemical composition, escamoles could be considered a promising source of suitable nutrients for human consumption and also as a complex food system for thermal analysis. ...
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In this work is presented the complete thermal analysis of polyols by direct methods such as simultaneous thermogravimetric and differential thermal analyzer (TGA-DTA), differential scanning calorimetry (DSC), modulated DSC (MDSC), and supercooling MDSC. The different thermal events in the temperature range of 113–553 K were identified for glycerol (GL), ethylene glycol (EG), and propylene glycol (PG). Boiling temperature (TB) decreased as GL > EG > PG, but increased with the heating rate. GL showed a complex thermal event at 191–199 K, identified as the glass transition temperature (Tg) and devitrification temperature (Tdv), and a liquid–liquid transition (TL-L) at 215–221 K was identified as the supercooling temperature. EG showed several thermal events such as Tg and Tdv at 154 K, crystallization temperature (Tc) at 175 K, and melting temperature (Tm) at 255 K. PG also showed a complex thermal event (Tg and Tdv) at 167 K, a second devitrification at 193 K, and TL-L at 245 K. For PG, crystallization was not observed, indicating that, during the cooling, the liquid remained as an amorphous solid.
... Previous studies have demonstrated that insects are a good source of macro and micronutrients making these insects a good option for the improvement of health and nutritional status of people living in rural and semi-arid zones [7][8][9]. The aim of this study was to assess the content of lipids and fat-soluble vitamins A and E in Escamoles ant eggs (Liometopum apiculatum M.) and to inform people living on areas where Escamoles are available (collectors and inhabitants of State of Hidalgo) by means of personal communication, of the benefits they could provide to their nutrition and health. ...
... The lipid content of Escamoles is about 34.96 g /100 g dry sample (Table 3), thus, Escamoles have enough lipids to allow fat-soluble vitamins absorption through the intestine. Additionally, in a previous study performed on Escamoles by our research group [9], the main lipids found were oleic acid (67.66%), linoleic acid (2.61%), and arachidonic acid (0.16%), which are unsaturated fatty acids. These have an important role in different processes; oleic acid is a precurssor for synthesis of linoleic acid and has antioxidant properties that protect biological membranes from free radicals. ...
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To assess lipids and fat-soluble vitamins A and E in Escamoles and inform the population about the benefits the intake of these edible insects may provide for human health. Results: Escamoles contain 34.96 g/100 g dry samples, Vitamin A, Retinol, 0.3024 mg/100 g and Vitamin E alpha-tocopherol, 3.29 mg/100 mg.
... Linoleic acid was high in both samples and was equally the most abundant poly-unsaturated fatty acid (PUFA) with values ranging between 41.9% (gold mohur) and 26.8% (aidan). The levels of linoleic acid (n-6) in this study were comparatively lower than 58.9-60.7% in three varieties of melon seeds and 67.7% in edible ant eggs (Virginia et al., 2013). Also the present C18:2 (n-6) fatty acid levels were higher than 7.52-9.07 ...
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Fatty acid levels of two edible and medicinal species: Delonix regia and Tetrapleura tetraptera seeds flour were investigated using standard analytical techniques. Among the saturated fatty acids (SFA), palmitic acid (17.2-49.4%) had the highest concentration in both samples. Oleic acid (19.7-21.0%) was most abundant among the mono-unsaturated fatty acids (MUFA). In both samples, palmitoleic acid recorded 0.00% concentration, whilst margaric acid (0.001-0.060%), lignoceric acid (0.001-0.079%) and arachidonic acid (0.065-0.080%) were found in trace amounts. Both samples were high in total poly-unsaturated fatty acids (PUFA) (26.9-42.7%). MUFA/SFA was less than 1.00 in both samples (0.375-0.584); PUFA/SFA was 1.18 (Delonix regia) and 0.507 (Tetrapleura tetraptera). Total unsaturated fatty acid (TUFA) (63.8%) was higher than total SFA(36.1%) in Delonix regia. In Tetrapleura tetraptera, SFA (53.1%) was more than TUFA (46.8%). 2n-6/3n-3 were high at 59.9 (Delonix regia) and 536 (Tetrapleura tetraptera). The correlation coefficient of the fatty acids was positively high and significant.
... L. apiculatum larvae are rich in proteins (37.3 to 39.7%), which contain most of the essential amino acids such as lysine, leucine, methionine, tyrosine, and tryptophan. The larvae also contain fats (36.87%), and carbohydrates (19.2%) as well as vitamins including A, C, B1, B2, B3 (Ladrón De Guevara et al., 1995;Ramos-Elorduy et al., 2002;Del Toro et al., 2009;Ramos-Rostro et al., 2012;Melo-Ruiz et al., 2013). Despite this current information about the nutritional composition of L. apiculatum larvae, information regarding their molecular protein composition remains unknown. ...
Article
The larvae of escamolera ant (Liometopum apiculatum Mayr) have been considered a delicacy since Pre-Hispanic times. The increased demand for this stew has led to massive collection of ant nests. Yet biological aspects of L. apiculatum larvae remain unknown, and mapping the proteome of this species is important for understanding its biological characteristics. Two-dimensional gel electrophoresis (2-DE) followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis was used to characterize the larvae proteome profile. From 380 protein spots analyzed, 174 were identified by LC-MS/MS and homology search against the Hymenoptera subset of the NCBInr protein database using the Mascot search engine. Peptide de novo sequencing and homology-based alignment allowed the identification of 36 additional protein spots. Identified proteins were classified by cellular location, molecular function, and biological process according to the Gene Ontology annotation. Immunity- and defense-related proteins were identified including PPIases, FK506, PEBP, and chitinases. Several hexamerin proteoforms were identified and the cDNA of the most abundant protein detected in the 2-DE map was isolated and characterized. L. apiculatum hexamerin (LaHEX, GeneBank accession no. MH256667) contains an open reading frame of 2199 bp encoding a polypeptide of 733 amino acid residues with a calculated molecular mass of 82.41 kDa. LaHEX protein is more similar to HEX110 than HEX70 from Apis mellifera. Down-regulation of LaHEX was observed throughout ant development. This work represents the first proteome map as well as the first hexamerin characterized from L. apiculatum larvae.
... A. Castillo-Andrade 1 , R. García-Barrientos 2 , M.A. Ruiz-Cabrera 1 , C. Rivera-Bautista 1 , J.D. Pérez-Martínez 1 , R. González-García 1 , C. Fuentes-Ahumada 3 and A. Grajales-Lagunes 1* which makes it unacceptable to the consumer. Despite the current information about the nutrimental components of escamoles (Ladrón de Guevara et al., 1995;Melo-Ruiz et al., 2013;Ramos-Elorduy et al., 2002;Ramos-Rostro et al., 2012), there is presently no report in the literature regarding quality loss of escamoles during storage. It is possible that endogenous enzymes and bacterial growth are involved in the gradual loss of the escamoles freshness. ...
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Entomophagy or consumption of insects has significantly increased worldwide, either for pleasure or to satisfy the food needs in developing countries. There are approximately 2,000 species of edible insects distributed in 120 countries. From these 2,000 species, about 540 are located in Mexico; one of the most consumed are the escamoles. Escamoles are larvae and pupae of the ant Liometopum apiculatum. Escamoles are nutritious because of their high content of protein, fat, carbohydrates and vitamin. However, during storage the quality of escamoles changes rapidly which affects the acceptability by the consumer. This loss of quality is probably a result of proteolytic activity of endogenous proteases. Therefore, the objectives of this study were to identify the classes of proteases in escamoles as well as to evaluate the effect of proteolytic activity on physicochemical and structural changes during storage. Proteases identification was conducted using specific inhibitors; structural changes, texture, and proteolytic activity were monitored at different days of storage. The highest proteolytic activities (P<0.05) were observed at pH 8, 9 and 10 and at 37 and 50 °C. Proteases were mainly inhibited by iodoacetic acid and soybean trypsin inhibitor showing that cysteine and serine proteases were dominant. High proteolytic activity, significant (P<0.05) reduction in texture and weight loss was observed during storage. The deterioration of escamoles was evident in analyses of images, where initial structure was lost during storage. These results indicate that different groups of proteases are associated with rapid deterioration of escamoles.
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The levels of crude fat, fatty acids, phospholipids and phytosterols were investigated in the melon seed samples. The most concentrated among the fatty acids was linoleic acid (58.9-60.7%) in all the samples. The bulk of the fatty acids was unsaturated (77.8-79.7%) while the saturated fatty acids were just 14.9-22.2 %, mainly from palmitic acid (9.54-10.8 %) and stearic acid (5.16-11.2%) representing 16.0-22.2% of the total fatty acids in the samples. The values of n-6/n-3 ratios (33.5-36.8) were above the recommended 5-10. Also, the energy contributed by PUFA (61.2-63.2% of total caloric value) was more than the recommended 4%. Among the phospholipids, lecithin was highest among the samples with values of 390-421mg/100g or 55.0-57.4 %, followed by phosphatidylinositol of 171-215 mg/100g or 25.0-30.0 %. Phosphatidylserine (PS) had the lowest concentration both in Cucumeropsis mannii and big Colocynthis citrullus variety. Cholesterol, cholestanol and ergosterol were found to be relatively low in all the samples with cholesterol occupying the list position. The values of cholesterol and cholestanol in the samples were highly varied as it was evident in the levels of coefficient of variation (CV %).
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Xochimilco es un centro importante en producción de nutrientes desde la época prehispánica hasta la actualidad, tanto para consumo local como de la metrópoli (Sahagun 1975). En esta región, la cultura indígena ha basado su alimentación, en la ingesta de maíz, chile, frijol, vegetales e insectos y bebidas como el pulque y agua de frutas; sin embargo, algunos recursos renova-bles del lugar no han sido debidamente estudiados. En Xochilmico se cuenta con más de veinte especies de insectos comestibles, de los cuales en esta investigación se presentan cinco de ellos, que corresponden a las estudiadas, y disponibles en diferentes épocas del año, de consumo y aceptación por diferentes grupos sociales. Gusanos de tepozán, gusanillos de nopal, capulmimichis, picudo de nopal y gusanos de maíz los cuales poseen un contenido de proteínas que va desde 45.25 a 60.75% y todos ellos con ocho aminoácidos esenciales. Estos organismos se consumen en estado larvario. Los insectos estudiados son ingeridos de forma alternativa ya que su disponibilidad es temporal; sin embargo, representan una fuente considerable de macronutrientes y en todos los casos están en un balance adecuado a los requerimientos para una buena nutrición.
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Importance of the Ratio of Omega 6/Omega 3 Essential Fatty Acids - Evolutionary Aspects, Simopoulos, A.P. The Importance of Omega 6/Omega 3 Fatty Acid Ratio in Cell Function - The Gene Transfer of Omega-3 Fatty Acid Desaturase, Kang, J.X. Omega 6/Omega 3 Ratio and Brain-Related Functions, Yehuda, S. Dietary Prevention of Coronary Heart Disease - Focus on Omega 6/Omega 3 Essential Fatty Acid Balance, de Lorgeril, M., Salen, P. Effects of an Indo-Mediterranean Diet on the Omega 6/Omega 3 Ratio in Patients at High Risk of Coronary Artery Disease - The Indian Paradox, Pella, D., Dubnov, G., Singh, R.B., Sharma, R. Berry, E.M. Manor, O. Omega 6/Omega 3 Fatty Acid Ratio - The Israeli Paradox, Dubnov, G., Berry, E.M. Linoleic Acid to Alpha-Linolenic Acid Ratio - From Clinical Trials to Inflammatory Markers of Coronary Artery Disease, Zampelas, A., Paschos, G., Rallidis, L., Yiannakouris, N. The Japan Society for Lipid Nutrition Recommends to Reduce the Intake of Linoleic Acid. A Review and Critique of the Scientific Evidence, Hamazaki, T., Okuyama, H. Omega 6/Omega 3 Polyunsaturated Fatty Acid Ratio and Cancer, Chaj s, V., Bougnoux, P. Omega 6/Omega 3 Fatty Acids and Arthritis, Cleland, L.G., James, M.J., Proudman, S.M.
Chapter
Early food composition studies were carried out to identify and determine the chemical nature of the principles in foods that affect human health. These studies, which were also concerned with the mechanisms whereby chemical constituents exert their influence, provided the basis for the early development of the science of nutrition (McCollum, 1957) and continue to be central to the nutritional sciences. Current knowledge of nutrition is still incomplete, and studies are still required, often at an ever-increasing level of sophistication, into the composition of foods and the role of these components and their interactions in health and disease.
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The FA composition of visceral oil extracted from farmed Atlantic salmon (Salmo salar L.) viscera was studied. Seventeen FA were identified in the extracted visceral oil, and the major FA were 18∶1n9, 16∶0, 16∶1n7, 20∶5n3 (EPA), 14∶0, and 22∶6n3 (DHA). The percentages of saturated, monounsaturated, and polyunsaturated FA in the total FA were 31.7, 36.0, and 32.2%, respectively. Compared with other fish oils, oil from farmed Atlantic salmon had much higher EPA (1.64 g/100 g) and DHA (1.47 g/100 g) contents. The FA profile of the salmon visceral oil was similar to that of the salmon fillet. Thus, the salmon visceral oil could be a replacement for the oil obtained from edible salmon fillet and used in functional foods or feeds requiring a high level of omega-3 FA. Furthermore, producing visceral oil is also beneficial to salmon fish industry by adding value back to the processing waste.
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Public interest in the health benefits of seafood lipids, or of fish oils, is a most unusual phenomenon because for once the recommendations of health authorities to "eat more fish" are in accord with newer and popular attitudes. Media exploitation of the more sensational health aspects is also generally in favor of more consumption of seafood. The public is however still confused by the multitude of species of fish and shellfish available, and in a quandary over whether fatty fish are risky in terms of calories or cholesterol, or of more benefit than lean fish in terms of omega-3 fatty acids. Most direct questions on how much omega-3 fatty acids are useful in the diet of an average individual may never be answerable until long term studies with humans are carried out. It does appear that marine fish can be broken down into four convenient categories: lean (including shellfish), low fat, medium fat and high fat; and in this review it is suggested that these could contribute, per 100 grams, respectively about 250, 750, 1000 and 2000 mg of total C20 + C22 omega-3 fatty acids. This intake can compare favorably with the alternative of commonly available fish oil capsules. Moreover this survey shows that at present the composite of total omega-3 fatty acids in fish and shellfish may contain roughly equal proportions of the functionally effective eicosapentaenoic acid, and of docosahexaenoic acid with its as yet unknown long-term biochemical effects, or be biased in favor of more of the latter. To assist the public, nutritionists, dietitians, and researchers this review discusses the distribution of fat in edible fish muscle, the classes of lipids encountered, and the major fatty acids of health interest. Included are limited numbers of analyses from parts of the world other than North America.
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The fatty acid profiles of 74 strains of mycolic acid-containing coryneform bacteria were examined by gas-liquid chromatography. All of the strains contained major amounts of straight-chain and monounsaturated fatty acids although some also possessed substantial amounts of 10-methyloctadecanoic acid. Iso- and anteiso-branched acids were not present. Five distinct fatty acid patterns were evident: (i) Corynebacterium diphtheriae, C. pseudotuberculosis and 'C. ulcerans' strains contained major amounts of hexadecanoic and hexadecenoic acids; (ii) C. glutamicum, C. xerosis and related saprophytic and animal-associated strains, predominantly hexadecanoic and octadecenoic acids; (iii) C. bovis, major amounts of octadecenoic and 10-methyloctadecanoic acids; (iv) 'C. mycetoides', significant amounts of heptadecanoic acid as well as hexadecanoic and octadecenoic acids; and (v) strains related to Rhodococcus possessed significant quantities of 10-methyloctadecanoic acid in addition to straight-chain and monounsaturated acids.