Edible protein-lipid

Biodegradable films made from edible biopolymers from renewable sources could become an important factor in reducing the environmental impact of plastic waste. Proteins, lipids, and polysaccharides are the main biopolymers employed to make edible films and coatings. Which of these components are present in different proportions and determine the properties of the material, as a barrier to water vapor, oxygen, carbon dioxide, and lipid transfer in food systems (Gomez-Guillen et al. 2002 and 2009). 

McHugh, T.H., and Krochta, J.M. (1994a). Water-vapor permeability properties of edible whey protein-lipid emulsion films. J. American Oil Chem. Soc. 71, 307-312. 

The materials used in these type of films include lipids, polysaccharides, and proteins. Starch (Maizura and others 2007), methylcellulose (Olivas and others 2003), hydroxypropyl cellulose (Brindle and Krochta 2008), chitosan (No and others 2007), xanthan gum (Mei and others 2002), alginate or zein (Zapata and others 2008), and soy protein (Park and others 2001) have been used for edible coatings. 

Various protocols and modifications have been reported in the literature on how to perform the TBA test. In foodstuffs, malonalde-hyde can be bound to various constituents of the food (e.g., proteins), and therefore it must somehow be released prior to determination. It is difficult to determine the optimal conditions for release of malonaldehyde as they differ from one material to another and require different conditions for hydrolysis. Heat and/or strong acid are thought to be essential for the liberation of malonaldehyde from precursors or bound forms, for condensation with TBA, and for maximal color development. For edible oil samples or lipid extracts, the test is simplified in that samples are directly dissolved in butanol and then an aliquot is reacted with TBA. Alternatively, a food sample can be heated with TBA solution and the red pigment that is formed can be extracted from the reaction mixture with butanol or a butanol/pyridine solution (Turner etal., 1954 Sinnhuberand Yu, 1958 Placer et al., 1966 Uchiyama and Mihara, 1978 Ohk-awa et al., 1979 Pokorny and Dieffenbacher, 1989). 

Se Speciation in Plants The presence of a number of volatile Se species was reported in edible allium plants such as garlic by GC-AES [79]. Selenomethionine, Se-methylselenocysteine, and y-glutamyl-Se-methyl-L-seleno cysteine were identibed in garlic and onion by HPLC-ICP-MS and ES-MS/MS [80]. Selenomethionine is the primary species found in all types of nuts (19D25 percent of the total Se) [30], sunBower [81], and mushrooms [36, 37], The distribution of Se among different fractions (lipid extract, low molecular weight, and protein fractions) of nuts and speciation analysis was studied [30]. Selenium was not detected in any of the lipid extracts obtained from the different types of nuts [30], Results obtained for Brazil nuts by SEC with on-line ICP-MS detection showed that approximately 12 percent of total Se was weakly bound to proteins [30],... 

Sanchez-Machado, D. I., Lopez-Cervantes, J., Lopez-Hernandez, J., and Paseiro-Losada, P. 2004a. Fatty acids, total lipid, protein and ash contents of processed edible seaweeds. Food Chem., 85, 439 144. 

Edible moisture barriers usually include hpids. Because of their apolar nature, these hydrophobic substances are capable of forming a water-impervious structure and reduce efficiently the water transfer. However, lipid-based materials are most of the time brittle so they are frequently combined with proteins and/or polysaccharides to improve their mechanical and structural properties (Wu et al. 2002). Several reviews focussing specifically on edible moisture barriers (Debeaufort et al. 2000 Koelsch 1994) and/or lipid-based edible films have been published (Baldwin et al. 1997 Callegarin et al. 1997 Greener and Fennema 1992 Hernandez 1994 Quezada-Gallo et al. 2000). The most recent review on lipid-based moisture barriers is that of Morillon et al. (2002). 

Stuchell, Y.M., and Krochta, J.M. (1995). Edible coating on frozen king salmon effect of whey protein isolate and acetylated monoglycerides on moisture loss and lipid oxidation. J. FoodSci. 60, 28-31. 

Pine nuts (pinon or pignolia) are the edible seeds within the pine cone of several varieties of pine trees (Pinus sp.) but most commonly Pinus pinea or stone pine . Pine nuts are harvested all over the world, most notably in Russia, China, North Korea, Spain, Italy, and Turkey, among others. Pine nuts contain 48-61% lipids by weight (1, 60). Other constiments of pine nut include carbohydrate (19.3%), protein (11.6%), water (5.9%), and ash (2.2%) (1). Pine nut oil contains predominantly linoleic acid (46.4%) and oleic acid (38.1%). Maritime pine nut Pinus pinaster) oil also contains two fatty acids that are unique among tree nut oils pinoleic acid and sciadonic acid (Figure 2), which exist at 7% each in pine nut oU and may have antiatherogenic effects (Table 8) (63). The phenolic acid composition of defatted pine nut meal is given in Table 2 and shows that caffeic acid is the predominant phenolic compound (14). 

Edible fats and oils (lipids) are derived from plant, animal, and marine sources. Fats and oils differ in that fats are solids at normal room temperature whereas oils are liquids under similar conditions. Lipids are recognized as essential nutrients in both human and animal diets. They provide the most concentrated source of energy of any foods. The caloric value of lipids (9 kcal/g) exceeds twice that of proteins and carbohydrates (4 kcal/g). Lipids not only contribute to flavor, color, odor, and texture of foods, but also confer a feeling of satiety after eating. Lipids also act as carriers of fat-soluble vitamins, supply essential fatty acids, and increase the palatability of foods. Dietary fats are often categorized as visible or invisible ... 

Edible films from polysaccharides, proteins, and/or lipid compounds are used in various food products to control gas transfer (15-17). 

Ketones (e.g., acetone) and alcohols (e.g., ethanol) are strongly bound to whole milk powder (24.3% lipids, 25.4% protein) and skimmed milk powder (0.6% lipids, 31.6% protein), fairly strongly to potato flakes (72.2% polysaccharide, 8% protein), but only weakly to instant coffee powder and strawberry powder. The interactions of the acetone with whole milk, skimmed milk and edible oil have already been shown in Fig. 

Meat is the edible part of animal, chicken, or fish carcasses. Its chemical composition is as follows 60-85% water, 8-23% protein, 2-15% lipids, 0.5-1.5% saccharides, and about 1% inorganic substances (Table 2.1). These quantities change significantly depending on the kind, age, sex, level of fattening, and part of the animal carcass. The largest fluctuations are observed in the contents of water and lipids. 

There are a large number of oilseeds some of them are very important because they yield edible oils. Among them are soybean (Glycine max), rapeseed (Brassica campestris), coconut (Cocos nucifera), and sunflower (Helianthus annuus). In addition to their lipid content, ranging from 20 to 55%, oilseeds often have substantial amounts of protein stored as protein bodies (30% or more v/v) and saccharides stored as cell wall components. Thus, the main subcellular structure consists of protein bodies 5 to 20 pm in diameter, surrounded by a cytoplasmic protein network in which are embedded the oil storage sites (Figure 2.1). These lipid bodies, sometimes referred to as spherosomes, are only 0.2 to 0.5 pm in diameter and are connected through a thin envelope. 

Edible nut seeds are a rich source of lipids and therefore they are calorie-dense (-500-700kcal/lOOg edible portion). In addition to lipids, nut seeds are a good source of quality proteins, certain minerals (such as selenium in Brazil nut) and vitamins (such as vitamin E in almond and hazelnut), and depending... 

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