Fat-free food

Flavourings consist of a blend of flavouring substances, which can be classified as lipophilic or hydrophilic. Fat or oil serves as carrier of lipophilic, and water as carrier of hydrophilic substances. Tab. 5.4 shows the variation in odour threshold values of selected flavouring substances when placed in water vs. oil. Due to these great variations, reduction in fat levels of foods will affect not only the intensity of the flavour but also its balance, since only little or no carrier system is available for lipophilic flavour components in water. The lipophilic part of the flavour cannot be retained in the food matrix and is released immediately. Fat-reduced or fat-free foods show high flavour impact initially which dissipates quickly, while full fat products gradually build up intensity and dissipate more slowly (schematically depicted in Fig. 5.25). 

Fig, 5,25 Schematic representation of time vs. flavour intensity curves of full fat and fat-reduced or fat-free foods when manipulated and warmed in the mouth [53]... 

In many conventional food products (e.g. fried foods, cheese products) fat or oil serves as precursor to desirable flavouring substances. Known examples of such substances are the oxidation products of fatty acids. These are not present in fat-free foods. This lack of flavour often cannot be mimicked by simply adding a flavouring... 

To find out more about how scientists are working to make fat-free foods taste good, visit the Ciencoe Science Web site. science.glencoe.com... 

W/O emulsions. Monoglycerides form lamellar phases bilayers separated by aqueous layers. These lipid bilayers can improve the texture of fat-free foods such as spreads, dressings and baked products and when sufficiently cooled they can gel [20]. 

K de Roos. How lipids influence food flavor. Food Technol 51 60-62, 1997. H Plug, P Haring. The role of ingredient-flavour interactions in the development of fat-free foods. Trends Food Sci Technol 4 150-152, 1993. 

The frequency of human vitamin E deficiency is very rare. In individuals at risk, it is clear that vitamin E supplements should be recommended to prevent deficiency symptoms. What about vitamin E supplement use in normal individuals Dietary changes such as decreasing fat intakes, substituting fat-free foods for fat-containing ones, and increased reliance on meals away from the home have resulted in decreased consumption of a-tocopherol-containing foods. Therefore, intakes of the vitamin E RDA of 15 mg a-tocopherol, may be difficult. Special attention to consuming nuts, seeds, and whole grains will improve a-tocopherol intakes alternatively, multivitamin pills can be consumed. 

There is more activity in dairy products than anywhere else in the food industry. Ice milk and fro2en yogurt, early leaders in the field, rose rapidly in sales then plummeted. Fat-free ice cream has been marketed, but final results are not yet available. Sales of these products have not cannibalized traditional ice cream (35). Standards for traditional ice cream call for a minimum of 10% butterfat. One fat-free ice cream product is prepared from nonfat milk (skim) and cellulose gum. Fat-free ice creams have encountered strong resistance in some segments of the retail trade. Retailers in Maine and New York, states with important dairy producing industries, refuse to sell such products (36). 

Treatment of ceUulose with acids results in preferential hydrolysis in the more accessible amorphous regions and produces a product known as microcrystalline ceUulose (MCC). MCC is used to prepare fat-free or reduced-fat food products, to strengthen and stabilize food foams, as a tableting aid, and as a noncalotic bulking agent for dietetic foods. It has GRAS status. 

Earlier animal work showed similar results in terms of urinary acid production from dietary precursors that could be converted into acid before excretion. However, most investigators used salts rather than foods containing the anion or its precursor. The addition of acid, in the form of hydrochloric, sulfuric, or ammonium chloride, acid phosphate salts, or ascorbate resulted in enhanced urinary acidity and concomitant calcium excretion. For example, in the detailed study of bone salt metabolism, Barzel and Jowsey (19) showed that the rat fed supplementary ammonium chloride subsequently lost more calcium, and developed markedly demineralized fat-free bone mass. 

The Hopkins paper was very interesting.Of course his foods are all comparatively crude and our positive exp t with fat-free art. p. f. m. is hard to understand except on the assumption of a store of the growth factor of the body.. .. The energy proposition gets a great set back by Hopkins work and our growth paper.. ..However, these accessory extracts may be an invaluable aid to us in studying the comparative role of proteins if they permit us to keep our animals in better form. The point in our paper which Hopkins questions is very important i.e., the quantity of p. f. m. that is sufficient, and it needs to be repeated perhaps. (25)... 

The authors also stated that their rats behaved differently from the three animals fed by Osborne and Mendel but that the difference could not be explained. Hopkins had found in earlier experiments that very small amounts of substances extracted with hot alcohol from foods would, when added to deficient diets, render them capable of some growth potential. It was apparent, to Hopkins at least, that hot alcoholic extractions of foods removed small amounts of effective growth promoter from the diet. Ether extraction as carried out by Osborne and Mendel in their fat-free experiments was considered by Hopkins to be inferior to alcoholic extraction. "The purpose of the present note is to indicate that there is still reason for a continuance of the search for special accessory substances of potent influence upon growth. It should be pointed out that Osborne and Mendel themselves admit that such substances may exist." (30)... 

No mention was made of the alcohol v. ether extraction of foods but in their paper reporting the results of feeding fat-free diets Osborne and Mendel stated clearly that none of the foods had been extracted with hot alcohol. Furthermore, they found it difficult to believe (this was in mid-1912) that skimmed milk could contain an important lipoid (fat-like substances such as lecithin, e.g.) in any adequate amount, "while... butter, which must contain some compounds of this type [is] inadequate." (32)... 

Nutritional orthodoxy in America tells us that high-fat foods, particularly those rich in satnrated fats, are nnhealthy. Americans are pretty much convinced intellectually if not in practice. A trip to any American supermarket will reveal a wealth of products labeled light, lite, lo-fat, reduced fat, fat-free, and anything else that advertising folks can dream np. We bny tremendous quantities of these prodncts and consnme them. Many Americans obsess abont food, seeing it not as a ronte to pleasnre bnt as a collection of chemicals to be ingested at yonr own risk. 

Bile is an important product released by the hepatocytes. It promotes the digestion of fats from food by emulsifying them in the small intestine (see p. 2770). The emulsifying components of bile, apart from phospholipids, mainly consist of bile acids and bile salts (see below). The bile also contains free cholesterol, which is excreted in this way (see p. 312). 

Guraya, H.S. and Toledo, R.T., Volume expansion during hot air puffing of a fat-free starch-based snack, ]. Food Sci., 59 (1994) 641-643. 

Three cups of low-fat or fat-free milk per day or an equivalent amount of low-fat yogurt and/or low-fat cheese (1.5 ounces = 1 cup of milk) provide an adequate amoimt of Ca for most adolescents. Children 2- to 8-years old require two cups of milk per day, or the equivalent in alternative dairy foods. A one cup serving of whole milk supplies 290 mg Ca. It was recently demonstrated that it was virtually impossible for adolescents not consuming dairy products in their diet, and without an intentional plan for... 

One of the standardized methods, electron spin resonance (ESR) technique, permits identification of food that contains a hard, dry matrix, e.g., bone. When food containing bone is irradiated, free radicals are produced and trapped in the crystal lattice of the bone, which can be detected by ESR spectroscopy [137]. Thermoluminescence of contaminating minerals for detection of radiation treatment of, e.g., spices and dried fruits can be successfully applied [138, 139]. Another standardized method that has been developed for identification of irradiated fat-containing foods is the mass-spectrometric detection of radiation-induced 2-alkylcyclobutanones after gas-chromatographic separation [140]. The... 

It is very common to combine methods in obtaining aroma isolates. The simultaneous distillation/extraction method previously described is an example. Another popular combination method initially involves the solvent extraction of volatiles from a food and then high-vacuum distillation of the solvent/aroma extract to provide a fat-free aroma isolate. This technique is broadly used today to provide high-quality aroma extracts for numerous purposes. The apparatus used in solvent removal has been improved upon to reduce analysis time and efficiency the modified method is termed solvent-assisted flavour extraction (SAFE) [16]. 

While that demonstration is an attention-grabber, it isn t realistic. You can t stuff yourself full of fat and expect chitosan to save you from dietary damnation. There s a limit to the amount of chitosan that the body can handle comfortably. One can easily handle a few grams a day, and the stuff will prevent the absorption of some ten to twenty grams of fat, but that would hardly make a dimple in the fat content of the cornucopia of rich foods the hucksters insist we can consume without guilt. Clearly, chitosan is no miracle. There is no fat-free lunch. But chitosan is not a total dietary dud, either. 

Milk This group contains dairy products. This includes milk, yogurt, and cheese. These are your calcium-rich foods. Two or three servings a day are sufficient. A serving is one cup of milk or yogurt or 1-1/2 to 2 ounces of cheese. Choose low-fat or fat-free milk, yogurt, and other milk products. If you don t or can t consume dairy products, choose lactose-free products. 

Dried apricots and apricot leather are nutritious, fat-free snack foods... 

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