Stabilization of edible animal fats during rendering

Summary Studies have shown that lard and edible beef fats can be stabilized effectively with phenolic antioxidants during pressure steam-rendering. Best results were obtained for a given stabilizer level with the individual phenolics butylated hydroxyanisole and butylated hydroxytoluene. Poorer results were obtained with the mixtures in propylene glycol.     

The stabilization of animal fats with antioxidants during rendering

Summary Studies have been made to determine the feasibility of stabilizing inedible animal fats with antioxidants during rendering. Results show that in many instances a very high stability fat and meat and bone scrap can be obtained from this practice. Factors affecting the variability of results are discussed. Presented at the 27th Fall Meeting of the American Oil Chemists’ Society, Nov. 2–4, 1953, Chicago, Ill. Journal Paper No. 81, American Meat Institute Foundation.     

Urethane foams from animal fats. VI. Improved properties of lard and tallow-based foams

Improved properties of fire retardant urethane foams prepared from hypobrominated lard and tallow have been obtained by purification of the polyols prior to their use. Hypobromination was carried out by epoxidation of the glycerides followed by treatment with gaseous HBr. The crude derivatives were extracted with acetone and separated from unreacted saturates at 5 C. One step hypochlorination of glycerides by use of acidified sodium hypochlorite has been carried out, and subsequent purification of the polyols led to minor foam property improvement. Fire retardant foams have also been prepared from soybean oil and monoolein using both of these general methods, although the acetone extraction step could be omitted. Presented at the AOCS Meeting, Chicago, September 1970. E. Market. Nutr. Res. Div., ARS, USDA.     

An integrated process of catalytic hydrolysis and membrane separation for fatty acids production from lard oil

An integrated process of catalytic hydrolysis and membrane separation was developed for fatty acids (FAs) production from lard oil. Both sulphonated cation exchange resin (SCER) and 0.98 g/g H₂SO₄ as catalysts were used to produce fatty acids (FAs) from lard oil by three‐step hydrolysis, respectively. Simultaneously, polyethersulphone (PES) ultrafiltration membrane was employed to separate glycerol and water from the products. The hydrophilicity and morphology of the pristine and used PES membranes were characterized by contact angle measurement and field‐emission scanning electronic microscopy, respectively. The final optimal yields of FAs obtained by SCER and H₂SO₄ catalysis at 100 °C and atmospheric pressure were 85.6 % at 16.0 h of operation and 94.5 % at 18.0 h of operation, respectively. Furthermore, the yield of FAs obtained from an integrated process of SCER‐catalyzed hydrolysis and membrane separation achieved up to 99.9 % at 10.0 h, 90 °C, and operating pressure of 100 kPa.

     

Use of animal fats in rations for beef cattle

Summary Choice yearling Hereford steers were fed pellets containing 5.53% edible beef tallow, 68.14% ground corn cobs, 14.73% soybean oil meal, 9.20% blackstrap molasses, 1.31% urea, and 1.08% feeding bonemeal. In addition to the pellets, the steers received ground ear corn, brome hay, vitamin A supplement, and trace minerals. The steers receiving this ration gained 300 pounds in a total feeding period of 150 days for an average daily gain of 2.0 pounds. Comparable steers on a standard ration consisting of ground shelled corn, soybean oil meal, brome hay, vitamin A supplement, and trace minerals gained 317 pounds with an average daily gain of 2.11 pounds. Another group of steers were fed corn oil pellets. These steers gained 261 pounds per head or an average daily gain of 1.74 pounds. No digestive disturbances were observed throughout the feeding period in Lot 2 fed the beef tallow pellets. There were no apparent differences in carcass quality when the animals were slaughtered. The beef tallow pellets were prepared to have approximately 75% as much energy as corn, assuming that one pound of fat contributed 2.25 times more energy than a pound of carbohydrates. In this feeding test the economy of gain was in favor of the group of steers fed the beef tallow pellets. Published with the approval of the director as Paper No. 628, Journal Series, Nebraska Agricultural Experiment Station.     

Enzymatic interesterification of lard and high-oleic sunflower oil with Candida antarctica lipase to produce plastic fats

Lard and high-oleic sunflower oil (Trisun® Extra) were interesterified at 55°C for 24 h with SP435 lipase from Candida antarctica to produce plastic fats. As the amount of trisun increased, percentage free fatty acid, unsaturated fatty acid/saturated fatty acid value, oxidizability, and the amount of 18:1 found at the sn-2 position of triglyceride products increased. Differential scanning calorimetry showed that the low-melting components in the product contained more 18:1 than the high-melting components. A 60:40 (w/w) ratio of lard to trisun had the widest plastic range (3–26°C). The scaled-up reaction to produce this blend resulted in a product that had 60.1% 18:1 at the sn-2 position compared to 44.9% for the physical blend. The solid fat content of the 60:40 interesterified mixture resembled soft-type margarine oil.     

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.     

Future prospects of animal production of fats and protein

Present trends in the global animal production of fats and protein are reviewed. The dominance of the West and the temperate latitudes is underlined, and the uniqueness of China and Japan are analyzed. The global disparities are based primarily on the ample soil resources in the West allowing for extensive production of feed crops, led by oilseeds. A second major input is fish protein, half the catches of fish from the oceans being converted into meal and oil. This kind of secondary or even tertiary production is unlikely to be copied under the parsimonious conditions of the poor world. The relative roles of oilseed and fish proteins are analyzed. Future trends are discussed on the basis of the FAO projections presented in the Indicative World Plan. One of 11 papers presented in the symposium “The World Supply of Edible Oils and Proteins”, AOCS Meeting, Atlantic City, October 1971.     

Determination of the glyceride structure of fats; analysis of 14 animal and vegetable fats

The glyceride compositions of seven animals and seven vegetable fats have been determined by GLC analysis of the oxidized esterified glycerides as described in an earlier paper in this series. The compositions determined are compared with those calculated from lipase hydrolysis data according to the method of VanderWal. Good agreement was found between the calculated and determined compositions for the majority of the 14 fats. The exceptions were human fat and the more satu-rated vegetable fats, palm oil and cocoa butter, where some discrepancies occurred. Issued as NRC No. 8052. National Research Council of Canada Postdoctorate Fellow.     

Optical activity of lactones from animal and vegetable fats

The isolation of optically active lactones from animal and vegetable fats is described. As the optical activity of lactones isolated from butterfat is ascribed to their biological origin, special attention was paid to the optical purity of the lactones. Lactone mixtures from butterfat, goat milk fat and coconut oil were found to be dextrorotatory, those from babassu oil levorotatory. The total lactone mixtures of two out of three samples of palm-kernel oil were slightly dextro-, whereas that of the third one was levorotatory. After isolation of the individual lactones from the mixtures, levo- and dextrorotatory lactones were demonstrated side by side in palm-kernel oil and in coconut oil. The δ-lactones of palmkernel oil were levo-, the γ-isomers dextrorotatory. In coconut oil only the δ-C₁₂ lactone was levorotatory, whereas the other components of the δ-series were dextrorotatory. The specific rotation [a] _d of the chemically pure lactones was considerably lower than that of model lactones, this being an indication of their optical impurity. As it was evident from model experiments that no racemization of the lactones occurred during isolation, it follows that both optical antipodes are formed in the fats in unequal amounts, via different pathways.     

Easy mass spectrometry for metabolomics and quality control of vegetable and animal fats

Easy ambient sonic spray ionization (EASI), a novel desorption/ionization technique for ambient mass spectrometry analysis, is shown to permit the characterization of different types of vegetable and animal fats. The taxonomic markers of the oils, mainly fatty acids and phenols, are extracted with methanol/water (1:1) solution and made alkaline with NH₄OH, then placed and dried on the surface of a glass tip and directly analyzed by EASI‐MS in the negative‐ion mode. EASI provides a supersonic cloud of charged droplets that causes efficient desorption and ionization of the oil markers directly from the surface of the glass tip. As proof‐of‐principle cases, EASI(?)‐MS was applied to genuine samples of olive oil, hazelnut oil, soybean oil, grape seed oil, canola oil, butter, and lard. Characteristic metabolomics EASI(?)‐MS profiles of fatty acids and eventually phenols were obtained.     

Investigations on physical refining of animal fats and vegetable oils

Alcohols, polyethyleneglycols, supercritical fluids, and some of their mixtures have been investigated as to their usefulness to purify animal fats and vegetable oils by extraction. The main impurities are free fatty acids. Phase equilibrium was measured as function of temperature and pressure. As primary substances abattoir fat and palm oil were used. Carbon dioxide, dimethylether, and mixtures thereof, likewise methanol and ethanol were tested as extractants for free fatty acids by counter-current extraction in a pilot plant including a high-pressure column and by cross-flow extraction on laboratory scale. With experiments and process simulations including the recovery of the extractants the deacidification of animal fats and vegetable oils was found to be possible. Polyethyleneglycols extract carotenes together with free fatty acids. With the physical refining methods investigated, the formation of waste materials was avoided.     

Dietary modifications of animal fats: status and future perspectives

The purpose of modifying animal fats is to produce high quality products, which meet the dietary recommendations for a reduced intake of fat in the human diet, notably that of certain saturated fatty acids and cholesterol, and an increased intake of mono- (MUFA) and polyunsaturated fatty acids (PUFA) in order to minimize the risk for obesity, cancer, cardiovascular, and other life-style diseases. The body fat of farm animals is partly synthesized from dietary carbohydrates, partly from dietary fatty acids. In monogastric animals, preruminants and poultry PUFAs are readily absorbed and deposited in the edible parts of the body and incorporated into egg yolk lipids. In ruminants, however, PUFAs are hydrogenated to mainly saturated fatty acids by the rumen microorganisms with some formation of MUFAs, trans-, odd-, branched chain, and conjugated fatty acids. The latter fatty acids are absorbed, deposited in adipose and muscle tissue and incorporated into milk lipids, unless dietary PUFAs are protected against hydrogenation. Thus, it is relatively easy to change the fatty acid composition of pork, poultry meat, lamb, and veal, whereas beef and milk can only be enriched significantly with PUFAs by manipulation. Products enriched with PUFAs are, however, prone to oxidation, and enrichment with antioxidants, notably with dietary vitamin E, is necessary in order to prevent the risk of oxidative damage.     

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.