Functional Applications of Specialty Lipids (SL)

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A functional lipid is similar to or may be a conventional fat or oil that is consumed as part of a normal diet, but is demonstrated to have physiologic benefits, i.e., beyond serving a nutritional function, it may reduce the risk of chronic disease.
The functionality of the lipids in food products varies from one product to another.

Functional Applications of Specialty Lipids (SL)

Plastic Fats for Foods. SL are texturally important in the manufacture of plastic fats such as margarine, modified butters, and shortenings. The physical property of any fat or oil is determined by the chain length and unsaturation of the FA and
their distribution among the three hydroxyl groups of glycerol. Fats with a higher
percentage of saturated fatty acids (SFA) tend to be solid at room temperature, and
those with a higher percentage of unsaturated FA tend to be liquid.
Interesterification alters the original order of distribution of FA in the glycerol
moiety producing fats with different melting and crystallization characteristics than
the parent fat. This allows the production of tailor-made fats to suit particular
foods. In the manufacture of margarine, the objective is to produce a fat mixture
with a steep SFC curve to obtain a stiff product in the refrigerator that spreads easily
upon removal and melts quickly in the mouth. When short- (SCFA) or medium-
chain fatty acids (MCFA) and long-chain fatty acids (LCFA) are interesterified,
they can produce TAG with good spreadability and temperature stability (10).
Due to the growing concern about the health implications of trans fatty acids
(TFA) in margarine, research interest has been generated in the production of zero
TFA margarine or shortenings. Interesterification of the butter stearin fraction and liquid
oils such as sunflower and soybean oils yield products with desirable spread characteristics and almost zero TFA. Palm stearin-sunflower oil (40:60 and 50:50)
blends subjected to transesterification using Pseudomonas lipase were shown to be
suitable for table margarine formulation. Seriburi and Akoh were able to produce
a soft-type margarine blend by interesterifying lard and high-oleic sunflower oil
(60:40) using SP 435 lipase from Cundidu antarctica. Palm stearin and palm kernel
olein were interesterified using sn-1,3-specific Rhizomucor miehei at a 40:60 ratio to
produce an experimental table margarine. Rousseau and Marangoni interesterified
butterfat and butterfat-canola blends enzymatically to produce a cold spreadable
butter. Interesterification was found to be a highly useful method for improving
butter spreadability, although it also resulted in loss of some butter flavor. Fomuso and

Akoh modified laurate canola enzymatically with stearic acid to produce a transfree
margarine. Unilever was granted a patent on a similar SL made with interesterified
lauric rapeseed oil (65%) and fully hydrogenated soybean oil (35%). The
interesterified oil can be used as a hardstock for blending with desirable liquid oils.
Trans-Free Fat Alternatives. In the fats and oils industry, TFA are formed during partial hydrogenation of PUFA. Hydrogenation is used to improve the consistency and oxidative stability of refined, bleached, and deodorized dietary fats. These fats are used mainly in margarines, shortenings, spreads, and confectioneries to
improve their textural properties, modify their melting and crystal behavior, and
enhance stability. Modification to improve the functional and nutritional properties
of fat is of interest to the food industry. Modification in structure can be achieved
through hydrogenation, chemical and enzymatic interesterification, genetic engineering,
and plant breeding techniques. Nonstructural modification approaches to producing fats with desirable or improved nutritional and physical properties include blending, such as in the production of Appetizer shortening and Good-Fry oil. Currently, about one third of the world’s edible fats and oils is hydrogenated, whereas aproximativelly 10% is either fractionated or interesterified.

Hydrogenation is common in highly unsaturated oils, such as soybean, rapeseed,
cottonseed, and fish oils, whereas fractionation is better applied to palm oil and
other more saturated oils. Hydrogenation will raise the melting point and reduce the iodine value of TAG as the oil is converted from a liquid at room temperature to semisolid plastic fats. The SFC of the modified fat as determined by pulsed NMR increases. TFA have higher melting points than cis FA, and therefore contribute considerably to the melting and plastic properties of fats, including baking performance.
The physiologic role of TFA has been controversial since the epidemiologic
study of Willett et al. suggested a positive correlation between the intake of
TFA and the risk of coronary heart disease. Because of health and nutritional concerns
raised by previous studies, there has been renewed interest in dietary TFA in Europe and North America. The US. Food and Drug Administration (FDA) issued a final rule on the labeling of the TFA contents of conventional foods and dietary supplements to be effective in January 2006. It is estimated by the FDA that adding trans fat information on the label would save between $900 million and $1.8 billion due to reduced medical costs, decreased pain and suffering, and greater productivity. The food industry is responding by repositioning themselves through research, reformulations, blending, and seeking of alternative fats, such as SL and genetically engineered fats. PepsiCo’s Frito-Lay division has already removed trans fat from their snacks and chips. Kraft said it would make its cookies and snacks with less fat and sugar, and McDonald’s
promised to reduce fats in fried foods.
SL are tailor-made fats and oils or TAG mixtures modified to approximate a particular FA or TAG composition to attain some desired property, such as reduced energy value, or a nutritional, physical, or functional property.

Examples include Appetizer shortening (a blend of animal fat, 85-95%, and vegetable
fat, 5-15%), Good-Fry oil (a high-oleic corn or sunflower oil), Bohenin (glycerol 1,3-dibehenate 2-oleate), Caprenin (contains octanoic, decanoic, and behenic acids), Salatrim (contains SCFA and LCFA), ARASCO (arachidonic acid single-cell oil, TAG produced by Mortierella alpina and containing 40% arachidonic acid), and DHASCO (DHA single-cell oil, TAG produced by Crypthecodinium cohnii and containing -40% DHA) oils. SL combines the unique characteristics of component FA, such as melting behavior, digestion, absorption, and metabolism, to enhance their use in foods, nutrition, and therapeutics. Indeed, the nutritional value of any TAG or SL and their physicochemical properties are determined by the FA composition and the positional distribution of acyl groups in the glycerol molecules. Exploration of lipase-catalyzed reactions, which can play a considerable role in the modification of fats and oils to produce trans-free alternatives to hydrogenated fats for various food applications, is warranted. List reviewed the reformulation and processing strategies to increase the health value of food fats without TFA.

Cocoa Butter and Cocoa Butter Alternatives. Cocoa butter is the fat of choice in the confectionery industry. Its polymorphism greatly affects the physical properties
of chocolate products, such as gloss, snap, contraction, heat resistance, quick and
sharp melting in the mouth, and bloom resistance. The limited availability of cocoa butter, which affects its cost, has prompted much research on alternatives that can be used as cocoa butter replacements or extenders in chocolate and confectionery coatings. There are no naturally occurring fats with physical properties similar to those of cocoa butter; all alternatives are made by blending and/or modifying fats. When using enzymatic processes for producing cocoa butter alternatives, several factors must be considered. The melting behavior must be very similar to that of cocoa butter to achieve the same cooling effect in the mouth. An alternative fat that is to be used in conjunction with cocoa butter should not interfere with the correct crystallization of the cocoa butter during tempering. The p crystals are the desirable polymorph in the confectionery industry.
The most common cocoa butter equivalents to date include palm oil, palm mid-fractions, illipe (Shorea stenoptera) fat, shea (Butyrospermum parkii) butter, sal (Shorea robusta) fat, and kokum (Garcinia indica) butter. Also some commercially
blended alternatives are available. When these natural fat sources are modified by incorporating either palmitic or stearic acid using sn-1- and sn- 3-selective lipases, it is possible to produce a cocoa butter-like fat whose FA composition closely resembles that of cocoa butter. An extensive review of cocoa butter alternatives is available. Foglia et al. suggested beef tallow as a possible base fat for producing SL that could be used as cocoa butter alternatives. Osborn and Akoh reported that SL made enzymatically by randomizing beef tallow or by incorporating stearic acid into beef tallow may be useful as a cocoa butter extender, because “chocolates” produced with the SL had some physical properties similar to those of chocolates produced with only cocoa butter. At present, efforts are underway in several laboratories to synthesize enzymatically cocoa butter alternatives with functionality identical to that of natural cocoa butter.

Healthier and More Stable Frying Fats. With the recent developments in genetic engineering, oilseeds can be genetically modified to produce fats and oils with
modified FA composition. These genetically modified fats and oils have various applications in the food industry, such as in deep frying. High-oleic sunflower oil
demonstrates excellent behavior with respect to thermoxidation and frying stability. To determine frying stability and performance, the characteristic odors and flavors of genetically modified soybean and canola oils were reported by Warner and Mounts. They found that flavor characteristics were significantly higher in potatoes fried in modified oils than those fried in standard oil. High-oleic corn oil has significantly better flavor and lower “room odor intensity” than normal or hydrogenated corn oil. Other genetically modified frying oils with improved frying characteristics include low-linolenic rapeseed and soybean oils.
Enova oil, described below, can also be used as healthy frying oil. Coating Lipids. SL can be used in coating applications. Coating is applied on food products for a variety of reasons. The edible coating is prepared basically from polysaccharides, proteins, and lipids. The first two components are effective in preventing or minimizing the transport of gases under conditions of relatively low humidity. Unlike these hydrophilic components, lipids are very effective as moisture barriers. Lipids can control mass transfer by preventing the movement of moisture, permanent gases, and aromas between the food and the external environment. Lipids are preferred as coating ingredients mainly to inhibit the loss of moisture and to improve the surface appearance of the finished products.
Many types of lipids are used as coating materials, including waxes, fats, oils, and chocolate. Other than waxes, acetylated glycerol monoesters of LCFA are used. For many applications, waxes were used predominantly as coating materials to protect against moisture loss especially for edible coatings. Other than moisture prevention, lipids are coated as a carrier for other ingredients such as nuts, or for protecting encapsulated materials from moisture absorption. Food products such as fruits and vegetables, confectioneries, nuts, refrigerated and frozen meat, baked products, and moisture-sensitive ingredients are coated with lipids. Waxes form flexible films at room temperature; they retain their flexibility at low temperature and are fairly effective barriers to moisture. TAG from various sources and compositions are also used for this purpose. Hydrogenation of many unsaturated oils such as coconut, cottonseed, peanut,
soybean, or other vegetable oils makes them solid or wax-like substances with physical characteristics suitable for many applications. This increase in melting point also improves their viscoelastic and mechanical properties and imparts greater chemical stability and increased moisture barrier properties.
Hydrogenation improves the melting point but at the same time, it increases the TFA content of fats. Alternatively, lipase-catalyzed modification can be employed for the same purpose but without TFA formation. Many high value-added products have been obtained by enzymatic modification of lipids. The palm oil mid-fraction was interesterified to obtain a cocoa butter equivalent by Rhizopus arrhizus lipase, which closely resembles cocoa butter in FA composition. Mixtures of palm kernel oil, cocoa butter, and anhydrous milk fat were studied for compound coating applications. We produced enzymatically large quantities of SL that were suitable for coating applications, specifically as a moisture barrier. Lipozyme IM60 lipase was used to conduct the acidolysis reaction of tristearin/lauric acidoleic acid at a 1:4:1 molar ratio. The melting peak of the SL product was 31.4 Celsius grade. The effectiveness of the SL was compared with cocoa butter-coated crackers and uncoated trackers as a control. The synthesized SL was better in preventing moisture absorption than cocoa butter. The potential for using SL in such applications appears to be great and warrants further study.

Enova Oil. Enova oilTM is a cooking oil marketed by Archer Daniels Midland
Company Kao LLC (Decatur, IL) as a joint venture between ADM and Kao Corporation (Japan). The oil was developed in Japan by Kao and first introduced as Enova Healthy Econa Cooking Oil in Japan in 1999. Enova oil was produced through a patented enzymatic process using a special blend of soybean and canola oils that results in an increased concentration (80% by weight) of DAG. Enova oil is cholesterol-free and an excellent source of vitamin E. The DAG in Enova contains 20-45% by weight oleic acid, 15-65% linoleic acid, and <15% linolenic acid.
The oil can be used in cooking, frying, salad dressing, and baking operations. Because most of the FA occur at the sn-1,3 positions of the glycerol, Enova is believed to be metabolized differently than conventional vegetable oils. Consequently, the oil is burned directly by the body to produce energy and is not stored as fat in the adipose tissue. Because the MAG produced as a result of lipase hydrolysis are poorly reassembled into chylomicrons, dietary FA move to the liver for P-oxidation. The oil is said to help with the fight against body fat and obesity and may help people lose weight when included in the diet. Enova oil can help lower serum triacylglycerols.

Lorenzo's Oil. Lorenzo's oil (LO) was invented by Michaela and August0 Odone, the parents of Lorenzo who had the rare genetic disorder called X-linked adrenoleukodystrophy (X-ALD). The neurological disorder causes the breakdown of the myelin that insulates the nerve fibers. Up to 17,000 males worldwide are affected with the disease and many die within 2 yr of manifestation. Lorenzo's oil is based on 22:1n-9 (erucic acid) and 18:ln-9 (oleic acid). The U.S. FDA is currently reviewing the possibility of using this oil for the treatment of X-ALD. The potency of LO as a specialty oil in the treatment of X-ALD requires further study. Using lipases to combine the emcic and oleic acids with a medium-chain or n-3 PUFA in the same glycerol backbone (also known as SL), as a delivery system, is worthy of investigation. Certainly the development of new oils to help with the management of this particular disease merits attention.

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author avatar muthusamy
1st Mar 2011 (#)

Authentic information on this subject. Very informative and educative. I have decided to follow yourself. Thank you for the share.

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