Fat in today’s food supply—Level of use and sources

Nutrient fat—food fats and oils, as well as fat from meat, milk, and other fat containing foods—in the U.S. food supply has increased ca. one-fourth over the past 60 years or so on a per person/day basis. Ca. two-fifths of the fat currently comes from fats and oils, including butter; over a third comes from meat (including fat pork cuts), poultry, and fish; and ca. one-eight comes from dairy products. This large increase in nutrient fat is due mainly to the use of more vegetable fats—margarine, shortening, and salad and cooking oils. The per capita amount provided by animal fats actually has decreased, because the large decreases in consumption of butter and lard are only partly offset by increases in fat associated with greater consumption of meats. Despite the decrease in consumption of animal fats, they continue to provide ca. one-fourth of the total calories. Although the proportion of calories from vegetable fats has increased, animal products still account for the largest share of the calories provided by fat. Shifts in sources of fat and the increased amount of fat have changed the fatty acid content of the food supply. One of five papers presented at the symposium, “Status of Fat in Food and Nutrition,” AOCS Fall Meeting, Chicago, September 1973. ARS, USDA.     

Studies on Nutritional Quality of Interesterified Fat Products

The nutritional quality of the fat products with melting range 36° to 37°C having been prepared from non-traditional oils like mowrah (Madhuca latifolia), ricebran (Oryzasativa) containing sal (Shorea robusta) and cottonseed (Gossypium hirstum) mixed with sal by interesterification (randomisation) were examined with rats and compared with that of “Vanaspati”, produced by hydrogenation of mixtures of liquid oils and used exclusively as a substitute of ghee (butter fat) in India. The average food intake, body weight gain, food efficiency ratio, weight of different organs, total lipid content of serum, liver, heart and kidney were similar in all the cases. Serum triglyceride levels were quite low in case of interesterified fats fed rats though total and free cholesterol levels were not significantly different. Serum phospholipid levels were slightly higher in case of the interesterified fats fed rats. Total and free cholesterol, phospholipid and triglyceride content of liver, kidney and heart were similar for the four dietary groups of rats. Serum lipids and liver lipids contain more polyunsaturated fatty acids when rats were raised on various interesterified fats in place of hydrogenated fat product “Vanaspati”.     

Substitutability of fractionated beef tallow for other fats and oils in the food and confectionery industries: An economic evaluation

The United States is the most important beef tallow producer in the world, supplying ca. 5.5 billion pounds annually. Approximately half of this beef tallow is exported at relatively low prices when compared to other fats and oils. Only ca. 10% of the total is used in domestic edible products. On the other hand, cocoa butter, coconut oil, palm oil, and palmkernel oil are imported oils whose demand for use in food and confectionery products has been increasing over the past few years. The first of these is the most expensive fat in the world. Beef tallow contains specific triglycerides which are also contained in these imported fats and oils. Through modern technology, beef tallow has been fractionated into products which are compatible with or superior to the imported fats and oils. It is visualized that products from fractionated beef tallow can be used as substitutes and extenders to cocoa butter, palm oil, and other fats and oils in the food and confectionery industries. The economic evaluation in this paper, analyzed through time series data and multiple regression techniques, established the past relationships between per capita consumption of confectionery food fat, beef tallow, cocoa butter, adjusted per capita disposable income, and adjusted costs of confectionery, beef tallow, and cocoa butter from 1956 to 1973. The substitutability of fats and oils was evaluated and the potential uses of fractionated beef tallow investigated. Presented in part at the AOCS meeting in Cincinnati, September 1975.     

Lard‐based fats healthier than lard: Enzymatic synthesis,physicochemical properties and applications

Lard has long been deemed superior to vegetable oils for culinary purposes due to its exceptional properties such as wide plastic range and special flavor values. Nevertheless, its usage over the years has seen a marked decrease due to awareness of its negative nutritional values such as high calorific content (see below) and saturated fatty acids. This paper looks into the possibilities of producing healthier lard‐based fats through “green” biocatalysis methods with particular attention given to the technical challenges of the process and their possible solutions. Alterations in physicochemical properties and application practicability of the modified lard‐based fats are also carefully elucidated.     

Studium der UV-Spektren oxydierter Fette III

Studies on the UV-Spectra of Autoxidized Fats III The author has determined the various properties of oxidized oils and fats with relation to the first maximum of extinction E₁ according the direct UV-method (E_1cm^1%). Following fats and oils were investigated: sunflower oil, rapeseed oil, peanut oil, soybean oil, corn oil, lard, butter, beef tallow and hardened edible fat.     

Fractionation of animal fat glycerides by crystallization from acetone. Am improved lard oil

Summary Various edible and inedible grades of animal fats, such as lard, grease, tallow, and selectively hydrogenated lard, grease and tallow were separated into “oils” and “stearins” by crystallization from acetone. The chemical and physical properties as well as the yields of oils and stearins obtained by this method are described. Antioxidants and metal deactivators are much more effective in stabilizing lard and grease oils produced from partially hydrogenated fats than in stabilizing corresponding products from unhydrogenated fats. Report of a study certain phases of which were made under the Research and Marketing Act of 1946. One of the laboratories of the Bureau of Agricultural and Industrial Chemistry, Agricultural Research Administration, United States Department of Agriculture.     

Crystallisation and melting behaviour of palm kernel oil and related products by differential scanning calorimetry

Lauric oils are valuable sources for oils suitable for various food applications. They are particularly useful as cocoa butter substitutes for which steep solid fat content profiles are required. Palm kernel oil is one such fat, which upon fractionation and/or hydro‐genation provides a variety of oil fractions with different oil composition and properties. The stearins have excellent properties for confectionery fats, while the oleins can be further hydrogenated to improve their properties. This paper gives an overview of the properties of products of palm kernel oil, produced from fractionation and hydrogena‐tion. The melting and crystallisation properties from differential scanning calorimetry studies are discussed in relation to the triacylglycerols of the oils.     

Gekoppelte LC-GC für die Analyse von Olivenölen

Coupled LC-GC for the Analysis of Olive Oils The analysis of the so-called sterol fraction of fats and oils can be strongly improved by the application of on-line coupled LC-GC. LC replaces saponification, the (difficult) extraction of the non-saponifiable and the clean-up by preparative thin layer chromatography. The proposed method eliminates most of the manual sample preparation work, is more accurate, and provides more information at the same time, since the free and esterified components are analyzed separately. Analyzing olive oils, mostly small admixtures of other oils can be detected. For the determination of solvent extracted oil in “extra virgin” or “pure” olive oils, the method is more suitable than the conventional determination of the triterpenedialcohols erythrodiol and uvaol. Finally pressed oil of first quality (“extra virgin”) can be distinguished from that of second quality (“pure” olive oil). Oils of second quality are usually the result of pression with an excessive delay after harvesting the olives.     

Exacerbation of heart and liver lesions in rats by feeding of various mildly oxidized fats

Groups of 40 male Charles River rats were fed diets containing cottonseed oil, olive oil, corn oil, soybean oil, coconut oil, chicken fat, beef fat, butter oil, lard and saturated medium chain triglycerides. The fats were fed fresh and after 40 hr aeration at 60 C, which hardly changed peroxide values. In addition, fresh and aerated soybean oil and lard were fed to W/Fu rats. Body weights and life span were significantly influenced by the kind of fat fed, but not by aeration. Many hearts exhibited unspecific focal myocarditis and focal fibrosis. The latter was graded in a blind test, which revealed highly significant differences in the incidence of severe lesions; those fed corn oil had the most, followed by cottonseed oil, soybean oil, olive oil, beef fat, saturated medium chain triglycerides, butter, chicken fat and lard, in that order. Feeding of aerated fat resulted in an increased incidence with six of the eight fats. The W/Fu rats had lower incidences, but those fed soybean oil had more than those fed lard, and aeration led to a higher incidence. Some heart sections stained with Light Green SF Yellowish revealed areas of muscle fibrils that did not accept the stain, probably as a consequence of cellular damage. Higher incidences of this lesion were associated with the same fats as was severe fibrosis, and feeding of aerated fats led to higher incidences. Many livers revealed marked proliferation of bile ducts. The groups fed cottonseed, soybean, olive and corn oils had higher incidences of severe lesions, and feeding of the oxidized oils led to still higher incidences. None of the results appeared to be associated with the fatty acid composition of the fats, which suggested that these long term effects may have been due to minor constituents in the individual fats. One of seven papers presented in the symposium “Biological Significance of Autoxidized and Polymerized Oils,” JOCS-AOCS Joint Meeting, Los Angeles, April 1972.     

Melting-point determination of fat products

A variety of methods exist for the determination of the melting point (mp) of fats. These include the Wiley mp (AOCS Method Cc 2–38), open capillary slip point, softening point and Mettler dropping point. The conditions under which the tests are performed influence the values obtained. Several of these methods were compared using a variety of fats, including margarine and soft margarine oils, lard, butter and hydrogenated Canola oils. The Mettler dropping-point values were found to coincide with the extrapolated solid fat curves obtained using wide-line NMR for all fats except butterfat. The reproducibilities of the Mettler dropping point and softening point were excellent; that of the slip point was poor. Presented at the 73rd AOCS annual meeting, Toronto, 1982.     

Alternatives to tropical fats based on high‐stearic sunflower oils

New high‐oleic high‐stearic sunflower lines produce oils that could be a source of disaturated triacylglycerol alternatives to tropical fats. These oils can be fractionated to produce stearins enriched in stearic acid with physical properties similar to cocoa butter and other confectionary fats without hydrogenation or transesterification. These fats can be produced in temperate countries from a well‐established crop like sunflower, and represent a healthy source of saturated fatty acids.     

Confectionery fats from palm oil and lauric oil

In the search for economical cocoa butter alternatives, palm and lauric oils have emerged as important source oils in the development of hard butters. Based on the method presented for categorizing hard butters, the lauric oils, primarily palm kernel and coconut, can be modified by interesterification and hydrogenated to yield lauric cocoa butter substitutes (CBS) which are both good eating and inexpensive. Fractionation, although adding to the cost of production, can provide lauric hard butter with eating qualities virtually identical to cocoa butter. Unfortunately, one factor identified with the lauric oils is their very low tolerance for cocoa butter. Palm oil, on the other hand, has been identified as a valuable component in all types of cocoa butter alternatives. It is a source of symmetrical triglycerides vital in the formulation of a cocoa butter equivalent (CBE). It can be hydrogenated or hydrogenated and fractionated to yield hard butters with a limited degree of compatibility with cocoa butter, allowing some chocolate liquor to be included in a coating for flavor enhancement. Palm oil is used with lauric oils as a minor component in interesterified lauric hard butters, as well as functioning as a crystal promoter in coatings formulated with a fractionated lauric CBS. While palm oil’s importance and flexibility have been duly noted, some important concerns remain from a market perspective. The fact that the CBE fats are very expensive suggests they offer limited cost savings compared to cocoa butter. The potential for CBE products is still questionable in those countries where chocolate labeling standards preclude the use of vegetable fats other than cocoa butter. The nonlauric CBS products, while cheaper than the CBE types and able to tolerate limited levels of cocoa butter, do not exhibit the level of eating quality characteristics present in the lauric hard butters. Some challenges remain for today’s oil chemists. An economical nonlauric CBS, made predominantly from palm oil, possessing the eating quality of a fractionated lauric CBS and exhibiting good compatibility with cocoa butter would be met with considerable interest by the chocolate and confectionery industries. As for the lauric oils, it would seem reasonable to assume that greater cocoa butter compatibility, if attainable, could enhance their potential for gaining even greater acceptance by confectionery manufacturers currently using pure chocolate. As for the CBE products, the major issue is cost. If the cost of a CBE could be reduced to a level which would allow a CBE to compete with the nonlauric and lauric cocoa butter substitutes, a major advancement in the evolution of cocoa butter alternative fats will have been achieved.     

Determination of milk fat in chocolates by gas-liquid chromatography of triglycerides and fatty acids

The combination of two routine methods is proposed to determine the content of milk fat (MF) in chocolates, which is applicable even in the presence of lauric fats or others. The content of MF is obtained from the sum of C₄₀, C₄₂, and C₄₄ medium-chain triglycerides, determined by capillary gas-liquid chromatography (GLC). A new method, based on methyl esters of lauric acid and on minor acids situated between myristic and palmitic, is proposed. It enables detection and estimation of potential lauric fats, as well as the determination of the actual content of MF. The influence of other vegetable and animal fats is discussed. We analyzed 45 MF samples extracted from industrial milk powders and from pure or fractionated MF for chocolate manufacturing or pastry by GLC of triglycerides. We also analyzed by capillary GLC the methyl esters from 22 of those fats. Mixtures of these 22 MF samples with a cocoa butter also were used for chromatographic analyses of methyl esters and triglyceride. Results from the various analytical methods have been presented.     

Meat fat formulation

Edible usage of meat fats has somewhat declined over the past years. This can be attributed to several factors. First, the advancement of hydrogenation technology has led to the development of highly functional vegetable oil products. Second, there has been an increased emphasis on Kosher products. Third, various questions relating cholesterol to risks of heart disease have generated some marketing concerns over meat fat usage. Meat fats are still a factor in the edible oils market. U.S. consumption of meat fats in 1976 was 4.1 billion pounds, approximately one billion pounds for edible usage. Because of their trigly ceride profiles, they are excellent sources of highly functional products for bakery applications. They have tended to be the “Cadillac” around which hydrogenated vegetable oil products have been developed. In addition, the economics of these products have generated significant savings for end users. Flavor attributes of meat fats have, in other cases, been the reason for their sole usage in certain specific products. In shortening formulation, meat fats are merely one of many triglyceride sources. They can be blended with any vegetable oil source. They can be subjected to the same processing as other oils in order to modify physical chemical properties such as SFI, melting point, consistency and oxidative stability. This paper will discuss specific applications where lard and tallow contribute unique functionality. It will then discuss various modifications which can be employed to insure more consistent performance or to customize products to specific applications.     

Spurennachweis von mehrfach verzweigten Fettsäuren in Fetten

Detection of Traces of Polybranched Fatty Acids in Fats A method for the detection and quantitative determination of saturated polybranched fatty acids in animal and vegetable fats is described. The method is based on gas-chromatographic determination of polybranched fatty acid methyl esters in the methyl esters which do not form urea adducts. The following amounts of polybranched fatty acids were determined in animal fats: whale oil 15 000 ppm., fish oil 6000 ppm., butter fat 4000 ppm., beef tallow 2000 ppm. and lard 110 ppm. In different vegetable oils and fats upto 200 ppm. of polybranched fatty acids were found. Not only the difference in total content of polybranched fatty acids but also differences in their percentage composition and retention volumes in gas-chromatograms were found. This method therefore offers the possibility of identification of some of the animal fats.     

The pancreatic hydrolysis of natural fats. III. The influence of the extent of hydrolysis on monoglyceride composition

Samples of lard and illipé butter have been hydrolyzed with pancreatic lipase for varying lengths of time, and the products estimated and analyzed. The composition of the monoglycerides from both fats, and of the tri- and diglycerides of illipé butter, were independent of the degree of hydrolysis; but the tri- and diglyceride fractions of lard became progressively more saturated with increasing hydrolysis. These results provide evidence for the sort of fatty acid distribution in fats envisaged by VanderWal. Representation of the results by a theoretical expression suggests that the rates of hydrolysis of the tri- and diglycerides are similar. It is concluded that analysis of the monoglycerides provides a better estimate of the distribution of fatty acids in natural fats than the analysis of the free fatty acids.     

Formulation of zero-<Emphasis Type="Italic">trans</Emphasis> acid shortenings and margarines and other food fats with products of the oil palm

The fruit of the oil palm yields two types of oil. The flesh yields 20–22% of palm oil (C16∶0 44%, C18∶1 39%, C18∶2 10%). This represents about 90% of the total oil yield. The other 10%, obtained from the kernel, is a lauric acid oil similar to coconut oil. Palm oil is semisolid, and a large part of the annual Malaysian production of about 14 million tonnes is fractionated to give palm olein, which is widely used for industrial frying, and palm stearin, a valuable hard stock. Various grades of the latter are available. Formulae have been developed by straight blending and by interesterification of palm oil and palm kernel oil to produce shortenings and margarines using hydrogenated fats to give the consistency required. Products that include these formulations are cake shortenings, vanaspati (for the Indian subcontinent), soft and brick margarines, pastry margarines, and reduced fat spreads. Other food uses of palm products in vegetable-fat ice cream and cheese, salad oils, as a peanut butter stabilizer, and in confectioners fats are discussed briefly here.     

An accelerated stability test using the peroxide value as an index

Summary A quick stability test for lard is described which depends on the peroxide content for identification of the rancid point. By its use ordinary samples of lard can be evaluated for stability in a working day. Oleo oil also is being tested by this method. It is applicable to edible fats and oils and hydrogenated shortenings. Typical peroxide curves for various fats and oils are shown. The effect of copper in accelerating oxidative rancidity is discussed.     

Analysis of fats and oils by gas-liquid chromatography and by ultraviolet spectrophotometry

1. Known mixtures of pure fatty acid methyl esters and a number of fats and oils as their methyl esters have been analyzed by conventional GLC with thermal conductivity detectors.
2. Percentage of fatty acid distribution determined by GLC agreed well with known percentages in model mixtures and with analysis by the spectrophotometric method for fats and oils.
3. Determination of very small amounts of arachidonic and pentacnoic acids in lard by GLC was not successful.