formulating functional foods with long-chain polyunsaturated fatty acids: challenges and...
TRANSCRIPT
Commentary
Formulating functional foods with long-chainpolyunsaturated fatty acids: Challenges and opportunities
Frederic Destaillats
Nestle Research Center, Lausanne, Switzerland
Keywords: Bioavailability / Functional foods / LC-PUFA
DOI: 10.1002/ejlt.201100325
See accompanying article by Borhaug et al. on pages 1235–1242
The development of functional
foods and supplements containing
bioactive lipids, such as esters of
long-chain PUFA (LC-PUFA), is
very challenging. Although the
requirements and nutritional value
of LC-PUFA are widely recognized,
their physical and chemical charac-
teristics are limiting the choice of
product applications, packaging
materials, processing, and shelf-life
conditions. In this issue of the
European Journal of Lipid Science
and Technology, Borhaug et al.
report a new technology to produce
water soluble concentrate of LC-
PUFA. Opportunities and chal-
lenges for this new generation of
ingredients are discussed in the
present commentary.
The health benefits of LC-PUFA
are nowadays well substantiated. n-3
LC-PUFA have been shown to reduce
the incidence of cardiovascular diseases
[1–6]. Emerging evidence also suggests
a protective effect against type-2 diabe-
tes [7], and an improvement of the
muscle protein synthesis rate in older
adults with the consumption of n-3 LC-
PUFA [8]. The level of n-3 LC-PUFA
in the circulation has been shown to
correlate with CVD risk [5] and regular
consumption of n-3 LC-PUFA is a rec-
ognized strategy to decrease CVD risk
factors. In infant nutrition, arachidonic
(ARA) and docosahexanoic (DHA)
acids are supplemented to starter infant
formulas to sustain adequate growth
and development of the infants [9, 10].
Daily recommendation guidelines
have been issued by different associations
for the general population [3, 4], people
treated for CVD [3, 4], and pregnant
women [11]. The current opinion is
that the consumption of n-3 LC-
PUFA is below the RDIs in the differ-
ent population groups [12, 13]. The
access to food products containing
n-3 LC-PUFA such as oily fish can
be limited to some countries due to
the economic, socio-cultural, or geo-
graphical constrains. The fortification
of food products or the development
of food supplements is therefore in
many countries a preferred approach.
However, formulation of foods con-
taining LC-PUFA is challenging.
Sustainable sourcing of high quality
n-3 LC-PUFA oils, technical chal-
lenges, and cost constrains help explain
why few food products containing n-3
LC-PUFA are commercially available
and can support nutritional
recommendations.
As an example, the supplement-
ation of infant nutrition products with
oil blends containing EFA and in some
cases n-3 LC-PUFA requires specific
handling procedures for the raw
materials in the factory, specific con-
ditions for addition, homogenization,
and finally preserving the finished
product with nitrogen. The described
process conditions can be used to man-
ufacture infant nutrition products but
are prohibitive or not adequate for some
product categories. Even if all these
requirements can be fulfilled, there in
a high probability that off-notes will
develop during shelf-life due to the poor
oxidative stability of n-3 LC-PUFA.
The oxidative degradation of LC-
PUFA can give rise to fishy and/or met-
allic off-notes and their perception in
certain food matrixes prevents their
acceptance by consumers. Strategies
to protect n-3 LC-PUFA have been
developed and technologies such as
microencapsulation have been shown
to improve in some conditions the
oxidative stability of n-3 LC-PUFA.
However, the scope of application of
such ingredients is limited due to the
nature of the coating materials, thermal
treatment required for product manu-
facturing and their resistance in high
water activity matrices.
The main challenges that have to be
considered when developing functional
foods with n-3 LC-PUFA are summar-
ized in Figure 1. The first parameter
Borhaug and coworkers prepared a
clear solution containing about
60 mg of n-3 LC-PUFA per milliliter.
This concentration is very relevant
for food formulations.
Eur. J. Lipid Sci. Technol. 2011, 113, 1293–1295 1293
� 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim www.ejlst.com
to select is the initial quality of the
LC-PUFA ingredient. Raw material
specification has to be established in
accordance with the best possible
requirements for the considered product
application. Once oxidative degradation
is initiated, the quality of the ingredient
rapidly becomes inacceptable for food
use. Thus, ample attention has to be
paid to the storage and handling of the
raw material in the factory as well as to
the processing conditions in order to
limit the initiation of the oxidative reac-
tion. A second major challenge is the
shelf-life stability of the product which
is highly determined by the selection of
the packaging materials and packaging
conditions. Lipids are usually very well
digested and absorbed and are there-
fore considered highly bioavailable
for the general population. However,
strategies to protect LC-PUFA from
oxidation by using encapsulation
technologies might potentially affect
the bioavailability of LC-PUFA. In
addition, it has been reported that
bioavailability of fatty acids differ if
the fatty acid is free, esterified to a short
alcohol (i.e., ethanol), or is provided
bound in glycerides [15, 16]. To ensure
a successful development, all the
elements mentioned in Figure 1 have
to be considered.
In the present issue of EJLST,
Borhaug and coworkers proposed a
process to prepare water soluble n-3
LC-PUFA concentrate from cod-liver
oil [17]. Water soluble n-3 LC-PUFA
ingredients are not commercially avail-
able and therefore the aim of the study
published by Borhaug and coworkers is
per se very innovative. Even though the
authors report also some limitations,
they propose the next steps to optimize
the quality of the ingredient and the
presented data are promising. The
basic process used by Borhaug and
coworkers starts with the complete
hydrolysis of fish oil, followed by urea
fractionation to concentrate the n-3
LC-PUFA and ultimately formation
of salt usingmeglumine in solution with
b-cyclodextrine. The use of b-CD to
solubilize lipids is well known to
biologists who use it to prepare lipid
dispersions for cell culture experiment
[18]. The process described is
applicable for the time being only at
laboratory scale since it involves the
usage of methanol, ethanol, urea, and
hexane.
The authors show that the process
developed decreases the level of
environmental contaminants. These
contaminants are extremely lipophilic
and, as hypothesized by the authors,
the data suggest that the purification
of the fatty acid salts by liquid-liquid
extraction steps is responsible of this
decrease. The authors noticed an
increase of the level of oxidation prod-
ucts by measuring peroxide and anisi-
dine values. This is not surprising
considering the number of process
steps used by the authors to prepare
their water soluble concentrate and
the poor oxidative stability of n-3 LC-
PUFA. One might think that a ‘‘deo-
dorization’’ step is required after the
urea-fractionation steps to lower the
concentration of primary and secon-
dary oxidation products before the
preparation of the salts. Working in
presence of nitrogen when mixing steps
are involved may also allow keeping the
concentration of oxygen in the oil phase
as low as technically possible.
The authors achieved the prep-
aration of a clear solution containing
about 60 mg of n-3 LC-PUFA per
milliliter. This concentration is very
relevant for food formulation since
the average daily recommendation for
healthy adults is around 200 mg n-3
LC-PUFA per day. As an example,
the formulation of a mini drink (80–
100 mL) with the objective to reach
50% of the daily recommended intake
will require to use 1.3–1.7 mL of a
stock solution of water soluble n-3
LC-PUFA at 60 mg/mL. This type of
ingredients offers many opportunities
for food processors to extend the choice
of products enhanced with n-3 LC-
PUFA. Technical improvements are
necessary to further develop this new
type of ingredient, and ultimately the
bioavailability of this n-3 LC-PUFA
derivative will have to be evaluated.
Overall the concept developed by
Borhaug and coworkers is very innova-
tive andmight extend the range of func-
tional foods containing n-3 LC-PUFA
on offer.
The author has declared no conflict of
interest.
References
[1] de Goede, J., Geleijnse, J. M., Boer,J. M., Kromhout, D., Verschuren,W.M.,Marine, (n�3) fatty acids, fishconsumption, and the 10-year riskof fatal and nonfatal coronary heartdisease in a large population of Dutchadults with low fish intake. J. Nutr.2010, 140, 1023–1028.
[2] Anderson, J. S., Nettleton, J. A.,Herrington, D. M., Johnson, W. C.et al., Relation of omega-3 fatty acidand dietary fish intake with brachialartery flow-mediated vasodilationin the Multi-Ethnic Study ofAtherosclerosis. Am. J. Clin. Nutr.2010, 92, 1204–1213.
[3] Kris-Etherton, P. M., Harris, W. S.,Appel, L. J., Omega-3 fatty acids andcardiovascular disease: New recom-mendations from the AmericanHeartAssociation. Arterioscler., Thromb.,Vasc. Biol. 2003, 23, 151–152.
[4] Kris-Etherton, P. M., Harris, W. S.,Appel, L. J., Fish consumption,fish oil, omega-3 fatty acids, andcardiovascular disease. Arterioscler.,Thromb., Vasc. Biol. 2003, 23, e20–e30.
[5] Harris, W. S., The omega-3 indexas a risk factor for coronary heart
Figure 1. ‘‘The Omega-3 Triumvirat.’’ The
key challenges to successfully develop food
products with n-3 LC-PUFA.
1294 F. Destaillats Eur. J. Lipid Sci. Technol. 2011, 113, 1293–1295
� 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim www.ejlst.com
disease. Am. J. Clin. Nutr. 2008, 87,1997S–2002S.
[6] Hooper, L., Thompson, R. L.,Harrison, R. A., Summerbell, C. D.et al., Risks and benefits of omega 3fats for mortality, cardiovascular dis-ease, and cancer: Systematic review.BMJ 2006, 332, 752–760.
[7] Brostow, D. P., Odegaard, A. O.,Koh, W. P., Duval, S. et al.,Omega-3 fatty acids and incidenttype 2 diabetes: The SingaporeChinese Health Study. Am. J. Clin.Nutr. 2011, 94, 520–526.
[8] Smith, G. I., Atherton, P., Reeds,D. N., Mohammed, B. S. et al.,Dietary omega-3 fatty acid supple-mentation increases the rate ofmuscle protein synthesis in olderadults: A randomized controlled trial.Am. J. Clin. Nutr. 2011, 93, 402–412.
[9] Birch, E. E., Carlson, S. E., Hoffman,D. R., Fitzgerald-Gustafson, K. M.et al., The DIAMOND (DHA IntakeAnd Measurement Of NeuralDevelopment) Study: A double-masked, randomized controlled clinicaltrial of the maturation of infant visualacuity as a function of the dietary levelof docosahexaenoic acid. Am. J. Clin.Nutr. 2010, 91, 848–859.
[10] Schwartz, J., Drossard, C., Dube, K.,Kannenberg, F. et al., Dietary intakeand plasma concentrations of PUFAand LC-PUFA in breastfed and
formula fed infants under real-lifeconditions. Eur. J. Nutr. 2010, 49,189–195.
[11] Koletzko, B., Cetin, I., Brenna, J. T.,Dietary fat intakes for pregnant andlactating women. Br. J. Nutr. 2007,98, 873–877.
[12] Denomme, J., Stark, K. D., Holub,B. J., Directly quantitated dietary(n-3) fatty acid intakes of pregnantCanadian women are lower than cur-rent dietary recommendations.J. Nutr. 2005, 135, 206–211.
[13] Blasbalg, T. L., Hibbeln, J. R.,Ramsden, C. E., Majchrzak, S. F.,Rawlings, R. R., Changes in con-sumption of omega-3 and omega-6fatty acids in the United States duringthe 20th century. Am. J. Clin. Nutr.2011, 93, 950–962.
[14] Haug, I. J., Sagmo, L. B., Zeiss, D.,Olsen, I. C. et al., Bioavailability ofEPA and DHA delivered by gelledemulsions and soft gel capsules.Eur. J. Lipid Sci. Technol. 2011,113, 137–145.
[15] Valenzuela, A., Nieto, S., Sanhueza,J., Nunez, M. J., Ferrer, C., Tissueaccretion and milk content of doco-sahexaenoic acid in female rats aftersupplementation with different doco-sahexaenoic acid sources. Ann. Nutr.Metab. 2005, 49, 325–332.
[16] Neubronner, J., Schuchardt, J. P.,Kressel, G., Merkel, M. et al.,
Enhanced increase of omega-3 indexin response to long-term n � 3 fattyacid supplementation from triacylgly-cerides versus ethyl esters. Eur. J.Clin. Nutr. 2011, 65, 247–254.
[17] Borhaug, H., Kristensen, M.,Brudeli, B., Sontum, P. C. et al.,Water soluble Omega-3: A conceptfor purification of fish oil and neutra-ceuticals? Eur. J. Lipid Sci. Technol.2011, 113, 1235–1242.
[18] Christian, A. E., Haynes, M. P.,Phillips, M. C., Rothblat, G. H.,Use of cyclodextrins for manipulatingcellular cholesterol content. J. LipidRes. 1997, 38, 2264–2272.
Abbreviations: b-CD, b-cyclodextrin;
LC-PUFA, long-chain PUFA; CVD,
cardiovascular diseases
Correspondence: Dr. Frederic Destaillats,
Nestle Research Center, Vers-chez-les-Blanc,
P.O. Box 44 CH – 1000 Lausanne 26,
Switzerland
E-mail: [email protected]
Fax: þ41-21-785-8553
See accompanying articlehttp://dx.doi.org/10.1002/ejlt.201000502
Received: September 9, 2011 / Accepted:
September 15, 2011
Eur. J. Lipid Sci. Technol. 2011, 113, 1293–1295 Formulating functional foods with long-chain polyunsaturated fatty acids 1295
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