Coconut oil stands out among its counterparts for its unique physical characteristics and wide-ranging uses. Its distinct properties, from flavor to durability, have made it a staple in culinary and medicinal practices for centuries.
Historically, coconut oil holds a revered position as one of the earliest oils utilized in cooking and medicine. Extracted from the fruit of the Cocas nucifera L., the process begins with obtaining oil-rich copra from dried coconut flesh, containing an oil content ranging from 50% to 65%.
Comprising approximately 90% saturated fat, coconut oil boasts a distinctive fatty acid composition, primarily including lauric acid, myristic acid, and palmitic acid. This unique blend contributes to its stability, making it less susceptible to oxidation compared to other oils. Moreover, its high lauric acid content grants it antimicrobial properties, enhancing its appeal both as a food ingredient and medicinal agent.
Coconut oil exhibits peculiar physical traits. Unrefined coconut oil solidifies at temperatures between 20 to 25°C and reaches its smoking point at 170°C, while refined variations have a higher smoking point of 232°C, rendering them suitable for various cooking techniques, from baking to frying.
Its remarkable shelf life, lasting up to two years, is owed to its resistance to high temperatures and oxidation. Proper storage is essential for preserving its quality, preferably in solid form below 24.5°C. Importantly, coconut oil remains stable even in warmer temperatures, setting it apart from other oils. Stainless steel, polyethylene, or fiberglass containers are recommended for storage to prevent deterioration, as materials like unlined carbon steel may compromise its quality over time.
Beyond its culinary uses, coconut oil holds a revered position in traditional medicine across diverse cultures. Its medicinal properties, including antibacterial and anti-inflammatory attributes, make it a popular remedy for various ailments, ranging from skin conditions to digestive problems.
In summary, the physical properties of coconut oil encompass a wide range of characteristics that contribute to its extensive versatility and enduring popularity. From its unique flavor profile to its ability to withstand high temperatures and prolonged shelf life, coconut oil remains highly valued as both a culinary essential and a traditional medicinal ingredient. Its versatility underscores its importance in ancient practices as well as contemporary contexts, making it a truly exceptional natural resource with multifaceted benefits.
Understanding the Diverse Physical Properties of Coconut Oil
Showing posts with label properties. Show all posts
Showing posts with label properties. Show all posts
March 29, 2025
November 2, 2022
Chemical and physical properties of vitamin E
Vitamin E is the major lipid-soluble component in the cell antioxidant defence system and is exclusively obtained from the diet. The tocopherols are viscous oils at room temperature, insoluble in water but soluble in ethanol and aprotic solvents. Vitamin E is a slightly yellow to amber, practically odorless and tasteless, clear, viscous oil, which darkens on exposure to air or light by oxidation.
Vitamin E is a generic term denoting eight different isomers among which α-tocopherol is the most important and most active.
The melting point of RRR-α-tocopherol is 3 °C. The optical rotations of tocopherols are very small and depend on the nature of the solvent. RRR-α-tocopherol (RRR-α-T), is known to be more bioactive than all-rac-α-tocopherol (all-rac-α-T), a synthetic racemic mixture of 8 stereoisomers.
Tocopherols are easily oxidized and can be destroyed by peroxides ozone and permanganate in a process catalyzed by light and accelerated by polyunsaturated fatty acids and metal salts.
The ultraviolet absorption spectra of tocopherols and tocotrienols in ethanol show an absorption maximum at 292–298 nm, while the infrared spectra show OH (2.8 ± 3.0 µm) and CH (3.4 ± 3.5 µm) stretching and a characteristic band at 8.6 µm.
Vitamin E is a fat-soluble vitamin that consists of a group of tocols and tocotrienols with hydrophobic character, but possessing a hydroxyl substituent that confers an amphipathic character on them.
The interactions between vitamin E and water are hydrophobic in nature; hence, vitamin E is found to be insoluble in water since vitamin E is non-polar and water is polar in nature. Solubility is reported for α-tocopherol in aqueous mixtures containing ethanol at 33 °C. It has very low solubility in pure water owing to hydrophobic repulsion.
α-Tocopherol is fluorescent with an emission maximum about 325 nm in a hydrophobic solution. The bond dissociation energy of α-tocopherol's O–H bond is 77.1 kcal mol−1.31 The pKa values for α-, β-, γ-, and δ-tocopherol in a micellar solution were reported as 13.1, 12.8, 12.7, and 12.6 respectively.
The α-tocopherol are unstable to air and light, particularly when in alkaline media. α-tocopherol acid succinate is insoluble in water, slightly soluble in alkaline solutions, soluble in alcohol, in ether, in acetone and in vegetable oils; very soluble in chloroform.
The partition coefficient of α-tocopherol is 12.2, while that for ascorbic acid is −1.85,30 showing their lipophilic and hydrophilic characters, respectively.
Chemical and physical properties of vitamin E
Vitamin E is a generic term denoting eight different isomers among which α-tocopherol is the most important and most active.
The melting point of RRR-α-tocopherol is 3 °C. The optical rotations of tocopherols are very small and depend on the nature of the solvent. RRR-α-tocopherol (RRR-α-T), is known to be more bioactive than all-rac-α-tocopherol (all-rac-α-T), a synthetic racemic mixture of 8 stereoisomers.
Tocopherols are easily oxidized and can be destroyed by peroxides ozone and permanganate in a process catalyzed by light and accelerated by polyunsaturated fatty acids and metal salts.
The ultraviolet absorption spectra of tocopherols and tocotrienols in ethanol show an absorption maximum at 292–298 nm, while the infrared spectra show OH (2.8 ± 3.0 µm) and CH (3.4 ± 3.5 µm) stretching and a characteristic band at 8.6 µm.
Vitamin E is a fat-soluble vitamin that consists of a group of tocols and tocotrienols with hydrophobic character, but possessing a hydroxyl substituent that confers an amphipathic character on them.
The interactions between vitamin E and water are hydrophobic in nature; hence, vitamin E is found to be insoluble in water since vitamin E is non-polar and water is polar in nature. Solubility is reported for α-tocopherol in aqueous mixtures containing ethanol at 33 °C. It has very low solubility in pure water owing to hydrophobic repulsion.
α-Tocopherol is fluorescent with an emission maximum about 325 nm in a hydrophobic solution. The bond dissociation energy of α-tocopherol's O–H bond is 77.1 kcal mol−1.31 The pKa values for α-, β-, γ-, and δ-tocopherol in a micellar solution were reported as 13.1, 12.8, 12.7, and 12.6 respectively.
The α-tocopherol are unstable to air and light, particularly when in alkaline media. α-tocopherol acid succinate is insoluble in water, slightly soluble in alkaline solutions, soluble in alcohol, in ether, in acetone and in vegetable oils; very soluble in chloroform.
The partition coefficient of α-tocopherol is 12.2, while that for ascorbic acid is −1.85,30 showing their lipophilic and hydrophilic characters, respectively.
Chemical and physical properties of vitamin E
October 4, 2021
Main roles of sugar in food
Sucrose, glucose and fructose are the most common sweeteners in nature.
Glucose is always less sweet than sucrose, whereas the sweetness of
fructose is highly dependent on temperature.
Sugar, which refers usually to sucrose, is natural and nontoxic, sweet testing, water soluble crystalline carbohydrates, and every 1 gram of sugar provide body 4K.calories. The main source for sugar is the beet sugar or cane sugar; also there are several sources such as honey, corn syrup, fruits, and vegetables….etc. Sucrose provides a sweetness flavour profile which is consistently liked by consumers at an economical cost.
The relatively high solubility of sucrose is an important parameter for its bulking effect in many foods and beverages. The dissolved sugar increases the viscosity of water-based solutions or mixtures, resulting in enhanced mouthfeel. Dissolved sugar lowers the freezing point of ice cream by preventing the water molecules from combining to form ice crystals, which slows down the freezing process.
By absorbing free water and increasing osmotic pressure, sugar reduces water activity in a food system (e.g. jam), resulting in reduced microbial and mold growth as well as extending the storage life of food. Also sugar can preserve fruits, either in syrup with fruit such as apples, pears.
Crystallization of sugars is desirable in products such as fondant, dragees, fudge etc., but not in many other products like jam and jellies. Crystallization occurs when the solubility limit of the sugar, typically sucrose or glucose, has been exceeded and a supersaturated environment has been created.
Sugar plays an important and single role in contributing to the flavor of food by interacting with other components to enhance or lessen certain flavors. By adding a small amount of sugar to cooked vegetables and meat enhance the food’s natural flavors, without making them taste sweet.
Texture is an expression of the sensation in the mouth. Sugar affects this by providing volume and consistency in many products such as bread, jam and beverages.In bread, sugar affects the volume of dough by speeding up the fermentation process. This gives the bread a more porous structure and softer crumb.
Main roles of sugar in food
Sugar, which refers usually to sucrose, is natural and nontoxic, sweet testing, water soluble crystalline carbohydrates, and every 1 gram of sugar provide body 4K.calories. The main source for sugar is the beet sugar or cane sugar; also there are several sources such as honey, corn syrup, fruits, and vegetables….etc. Sucrose provides a sweetness flavour profile which is consistently liked by consumers at an economical cost.
The relatively high solubility of sucrose is an important parameter for its bulking effect in many foods and beverages. The dissolved sugar increases the viscosity of water-based solutions or mixtures, resulting in enhanced mouthfeel. Dissolved sugar lowers the freezing point of ice cream by preventing the water molecules from combining to form ice crystals, which slows down the freezing process.
By absorbing free water and increasing osmotic pressure, sugar reduces water activity in a food system (e.g. jam), resulting in reduced microbial and mold growth as well as extending the storage life of food. Also sugar can preserve fruits, either in syrup with fruit such as apples, pears.
Crystallization of sugars is desirable in products such as fondant, dragees, fudge etc., but not in many other products like jam and jellies. Crystallization occurs when the solubility limit of the sugar, typically sucrose or glucose, has been exceeded and a supersaturated environment has been created.
Sugar plays an important and single role in contributing to the flavor of food by interacting with other components to enhance or lessen certain flavors. By adding a small amount of sugar to cooked vegetables and meat enhance the food’s natural flavors, without making them taste sweet.
Texture is an expression of the sensation in the mouth. Sugar affects this by providing volume and consistency in many products such as bread, jam and beverages.In bread, sugar affects the volume of dough by speeding up the fermentation process. This gives the bread a more porous structure and softer crumb.
Main roles of sugar in food
August 2, 2020
General physical properties of protein
Proteins (Greek proteios, “primary” or “of first importance”) are biochemical molecules consisting of polypeptides joined by peptide bonds between the amino and carboxyl groups of amino acid residues.
Proteins are the building blocks of life and there are estimated to be almost one million different proteins in a normal cell. Each protein has very different and unique physical properties.
*Proteins are colorless and usually tasteless. These are homogeneous and crystalline.
*Size. Proteins are very large polymers of amino acids with molecular weights that vary from 6000 amu to several million amu. Proteins are too large to pass through cell membranes, and are contained within the cells where they were formed unless the cell is damaged by disease or trauma.
*Structure. The proteins range in shape from simple crystalloid spherical structures to long fibrillar structures.
A. Globular proteins- These are spherical in shape and occur mainly in plants, esp., in seeds and in leaf cells. These are bundles formed by folding and crumpling of protein chains. e.g., pepsin, edestin, insulin, ribonuclease etc.
-dissolve in water or form stable suspensions.
-not found in structural tissue but are transport proteins, or proteins that may be moved easily through the body by the circulatory system
-e.g., hemoglobin and transferrin.
B. Fibrillar proteins- These are thread-like or ellipsoidal in shape and occur generally in animal muscles. Most of the studies regarding protein structure have been conducted using these proteins. e.g., fibrinogen, myosin etc.
-insoluble in water
-major components of connective tissue, elastic tissue, hair, and skin
-e.g., collagen, elastin, and keratin.
*Aggregation. Physical protein aggregation results from the association of unfolded proteins. According to the Lumry-Eyring model, the native protein is transformed in a transitional protein species that is prone to associate and to form protein aggregate. The protein aggregation pathway occurs in three steps:
(1) protein unfolding;
(2) association of unfolded monomers in oligomers; and
(3) nucleation, growth and condensation in aggregates
*Denaturation. Denaturation refers to the changes in the properties of a protein. In other words, it is the loss of biologic activity. In many instances the process of denaturation is followed by coagulation— a process where denatured protein molecules tend to form large aggregates and to precipitate from solution.
*Amphoteric. Like amino acids, the proteins are amphoteric, i.e., they act as acids and alkalies both. Depending on pH, they can exist as polyvalent (cations, anions or zwitter ions). These migrate in an electric field and the direction of migration depends upon the net charge possessed by the molecule. The net charge is influenced by the pH value. Each protein has a fixed value of isoelectric point (pl) at which it will move in an electric field.
By definition the net charge is zero and the total charge is maximal at the isoelectric point. Lowering or raising the pH tends to increase the net charge towards its maximum, while the total charge always becomes less than at the isolectric point.
*Solubility. The solubility of proteins is influenced by pH. Solubility is lowest at isoelectric point and increases with increasing acidity or alkalinity. This is because when the protein molecules exist as either cations or anions, repulsive forces between ions are high, since all the molecules possess excess charges of the same sign. Thus, they will be more soluble than in the isoelectric state.
Two different types of protein solubility are distinguished. True or thermodynamic solubility refers to the concentration of the protein in solution, which is in equilibrium with a crystalline solid phase of that protein. In contrast, apparent solubility corresponds to the concentration of protein in a solution, which is in equilibrium with a solid amorphous precipitate of the same protein.
*Optical activity. The optical activity of proteins is due not only to asymmetry of amino acids but also to the chirality resulting from the arrangement of the peptide chain.
General physical properties of protein
Proteins are the building blocks of life and there are estimated to be almost one million different proteins in a normal cell. Each protein has very different and unique physical properties.
*Proteins are colorless and usually tasteless. These are homogeneous and crystalline.
*Size. Proteins are very large polymers of amino acids with molecular weights that vary from 6000 amu to several million amu. Proteins are too large to pass through cell membranes, and are contained within the cells where they were formed unless the cell is damaged by disease or trauma.
*Structure. The proteins range in shape from simple crystalloid spherical structures to long fibrillar structures.
A. Globular proteins- These are spherical in shape and occur mainly in plants, esp., in seeds and in leaf cells. These are bundles formed by folding and crumpling of protein chains. e.g., pepsin, edestin, insulin, ribonuclease etc.
-dissolve in water or form stable suspensions.
-not found in structural tissue but are transport proteins, or proteins that may be moved easily through the body by the circulatory system
-e.g., hemoglobin and transferrin.
B. Fibrillar proteins- These are thread-like or ellipsoidal in shape and occur generally in animal muscles. Most of the studies regarding protein structure have been conducted using these proteins. e.g., fibrinogen, myosin etc.
-insoluble in water
-major components of connective tissue, elastic tissue, hair, and skin
-e.g., collagen, elastin, and keratin.
*Aggregation. Physical protein aggregation results from the association of unfolded proteins. According to the Lumry-Eyring model, the native protein is transformed in a transitional protein species that is prone to associate and to form protein aggregate. The protein aggregation pathway occurs in three steps:
(1) protein unfolding;
(2) association of unfolded monomers in oligomers; and
(3) nucleation, growth and condensation in aggregates
*Denaturation. Denaturation refers to the changes in the properties of a protein. In other words, it is the loss of biologic activity. In many instances the process of denaturation is followed by coagulation— a process where denatured protein molecules tend to form large aggregates and to precipitate from solution.
*Amphoteric. Like amino acids, the proteins are amphoteric, i.e., they act as acids and alkalies both. Depending on pH, they can exist as polyvalent (cations, anions or zwitter ions). These migrate in an electric field and the direction of migration depends upon the net charge possessed by the molecule. The net charge is influenced by the pH value. Each protein has a fixed value of isoelectric point (pl) at which it will move in an electric field.
By definition the net charge is zero and the total charge is maximal at the isoelectric point. Lowering or raising the pH tends to increase the net charge towards its maximum, while the total charge always becomes less than at the isolectric point.
*Solubility. The solubility of proteins is influenced by pH. Solubility is lowest at isoelectric point and increases with increasing acidity or alkalinity. This is because when the protein molecules exist as either cations or anions, repulsive forces between ions are high, since all the molecules possess excess charges of the same sign. Thus, they will be more soluble than in the isoelectric state.
Two different types of protein solubility are distinguished. True or thermodynamic solubility refers to the concentration of the protein in solution, which is in equilibrium with a crystalline solid phase of that protein. In contrast, apparent solubility corresponds to the concentration of protein in a solution, which is in equilibrium with a solid amorphous precipitate of the same protein.
*Optical activity. The optical activity of proteins is due not only to asymmetry of amino acids but also to the chirality resulting from the arrangement of the peptide chain.
General physical properties of protein
November 8, 2019
Capsaicin in chili pepper
Chilies are the berries of the genus Capsicum (family: Solanaceae) and they are used variously as a pungent flavor in food, natural plant colour, pharmaceutical ingredient and as sprays for riot control and self-defense.
Chilies have a hot taste. This comes from capsaicinoid compounds that are amide acids from vanilinamine and fatty acid chain branched at C9 and C11. Capsaicinoid consists of capsaicin, dihydrocapsaicin, homocapsaicin, and homodihydro-capsaicin. 69% of Capsaicinoid is capsaicin, which is a marker compound and has an affect on stimulating hair growth.
Capsaicin is a compound found in chili p fruit and responsible for their burning and irritant effect. Capsaicin is lead in bitterness chili fruit, thus red chili more hot taste than green chili, because the content of capsaicin of red chili two or three fold more than green chili fruits.
Capsaicin was first purified in 1876 but its structure started to be described only in 1919. Capsaicin presents a nonpolar phenolic structure and thus cannot be solubilized in water. The main solvents used to extract and maintain capsaicin properties are nonpolar solvents such as ether, benzene, dimethyl sulfoxide and acetone, but ethanol can also be used as a solvent due to its mixed properties.
Capsaicin is also the active principle which accounts for the pharmaceutical properties of chilies. It has been used as a topical analgesic against arthritis pain and inflammation. Capsaicin binds to the same group of nociceptors which also leads to the sensation of pain from heat and acid. It has also been reported to show anticancer effect.
Capsaicin has also been reported to show protective effects against high cholesterol levels and obesity. Capsaicin and other members of the capsaicinoids group produce a large number of physiological and pharmacological effects on the gastrointestinal tract, the cardiovascular and respiratory system as well as the sensory and thermoregulation systems.
Chilies have a hot taste. This comes from capsaicinoid compounds that are amide acids from vanilinamine and fatty acid chain branched at C9 and C11. Capsaicinoid consists of capsaicin, dihydrocapsaicin, homocapsaicin, and homodihydro-capsaicin. 69% of Capsaicinoid is capsaicin, which is a marker compound and has an affect on stimulating hair growth.
Capsaicin is a compound found in chili p fruit and responsible for their burning and irritant effect. Capsaicin is lead in bitterness chili fruit, thus red chili more hot taste than green chili, because the content of capsaicin of red chili two or three fold more than green chili fruits.
Capsaicin was first purified in 1876 but its structure started to be described only in 1919. Capsaicin presents a nonpolar phenolic structure and thus cannot be solubilized in water. The main solvents used to extract and maintain capsaicin properties are nonpolar solvents such as ether, benzene, dimethyl sulfoxide and acetone, but ethanol can also be used as a solvent due to its mixed properties.
Capsaicin is also the active principle which accounts for the pharmaceutical properties of chilies. It has been used as a topical analgesic against arthritis pain and inflammation. Capsaicin binds to the same group of nociceptors which also leads to the sensation of pain from heat and acid. It has also been reported to show anticancer effect.
Capsaicin has also been reported to show protective effects against high cholesterol levels and obesity. Capsaicin and other members of the capsaicinoids group produce a large number of physiological and pharmacological effects on the gastrointestinal tract, the cardiovascular and respiratory system as well as the sensory and thermoregulation systems.
Capsaicin
in chili pepper
February 12, 2019
Common properties of protein
Proteins play a fundamental role not only in sustaining life, but also
foods derived from plants and animals. Proteins exhibit a number of
common properties that just be accounted for in any definition of these
compounds:
*There are polymeric of high molecular weight, which are built up by the linking together of a large number of small molecules.
*They are amphoteric, i.e., they being able to act as an acid or a base. This enables them to resist small changes in pH.
*Following complete hydrolysis of a protein, the hydrolysate consists
entirely of amino acids (except that additional groups, such as heme,
iron, copper, may also be found in the case of a conjugate protein). It
is commonly recognized that amino acids being linked by peptide bonds
formed between α-amino and α-carboxylic acid groups of neighboring amino
acids in the polypeptide sequence.
*In their polymeric structures, the amino acid units of proteins are joined together in definite sequences and exist in definite three-dimensional conformations. This sequence built from a limited number of well-defined building blocks, the 20 genetically determined amino acids and a smaller number of posttranslational modifications of them.
Common properties of protein
*There are polymeric of high molecular weight, which are built up by the linking together of a large number of small molecules.
*They are amphoteric, i.e., they being able to act as an acid or a base. This enables them to resist small changes in pH.
*In their polymeric structures, the amino acid units of proteins are joined together in definite sequences and exist in definite three-dimensional conformations. This sequence built from a limited number of well-defined building blocks, the 20 genetically determined amino acids and a smaller number of posttranslational modifications of them.
Common properties of protein
April 26, 2018
Lauric acid
Lauric acid is a major fatty acid found in “tropical oils. Chemically Lauric acid is known as n-Dodecanoic acid, Dodecylic acid, Dodecoic acid; Laurostearic acid, Vulvic acid, 1-Undecanecarboxylic acid and Duodecylic acid.
The molecular formula for lauric acid is C12H24O2 . It is colorless needles, insoluble in water; soluble in alcohol and ether. Boiling point 298.9 °C; melting point 44 °C; density 0.833.
There are only a few basic foods that contain lauric acid more than trace amounts. These foods include: extracted lauric acids (coconut, palm kernel), whole coconut, cream coconut (bar), coconut cream (fresh or canned), coconut milk (fresh or canned), heavy cream, table cream, half and half, whole milk.
Commercial lauric acid is usually a mixture of solid acids obtained by saponifying coconut oil or it is the residue remaining after removal of caproic, caprylic and capric acids from the mixed acids by distillation.
In the human body, lauric acid is converted into a highly beneficial compound called monolaurin, an antiviral, antibacterial, and antiprotozoal monoglyceride that destroys a wide variety of disease causing organisms. Among saturated fatty acids, lauric acid has been shown to contribute the least to fat accumulation.
Lauric acid
The molecular formula for lauric acid is C12H24O2 . It is colorless needles, insoluble in water; soluble in alcohol and ether. Boiling point 298.9 °C; melting point 44 °C; density 0.833.
There are only a few basic foods that contain lauric acid more than trace amounts. These foods include: extracted lauric acids (coconut, palm kernel), whole coconut, cream coconut (bar), coconut cream (fresh or canned), coconut milk (fresh or canned), heavy cream, table cream, half and half, whole milk.
In the human body, lauric acid is converted into a highly beneficial compound called monolaurin, an antiviral, antibacterial, and antiprotozoal monoglyceride that destroys a wide variety of disease causing organisms. Among saturated fatty acids, lauric acid has been shown to contribute the least to fat accumulation.
Lauric acid
March 26, 2018
The influence of color on food acceptance
In spite of the numerous ways by which the appearance attributes of food affect consumer acceptance, the majority of research on the role of appearance in food acceptance has focused on the influence of color.
Color is an important property of foods that adds to enjoyment of eating. Of the three sensory properties of foods; food scientists tell that color is more important than flavor and texture in the initial food selection process.
On study showed that when jellies were colored in an atypical manner, the fruit flavors were incorrectly identified. It appears that color references for foods are the result of experience, culture and conditioning.
In addition, the colors of food contribute significantly to people to enjoy their meals. For this reason it is desirable to maintain as much of the natural color of fresh and processed foods as possible.
The food processer makes every effort to retain good color characteristics of his/her food products because he or she understands the importance of this property in promoting his/her sales.
Color variations in foods throughout the seasons and the effect of food processing and storage often require that manufacturers add color to certain foods to meet consumer expectations. The general principles for the application of colors to products are described with the overall aim of matching what the consumer expects from the particular food product.
Account must be taken of the effects of pH and processing, especially browning from the Maillard reaction and loss of initial color.
The influence of color on food acceptance
Color is an important property of foods that adds to enjoyment of eating. Of the three sensory properties of foods; food scientists tell that color is more important than flavor and texture in the initial food selection process.
On study showed that when jellies were colored in an atypical manner, the fruit flavors were incorrectly identified. It appears that color references for foods are the result of experience, culture and conditioning.
In addition, the colors of food contribute significantly to people to enjoy their meals. For this reason it is desirable to maintain as much of the natural color of fresh and processed foods as possible.
The food processer makes every effort to retain good color characteristics of his/her food products because he or she understands the importance of this property in promoting his/her sales.
Color variations in foods throughout the seasons and the effect of food processing and storage often require that manufacturers add color to certain foods to meet consumer expectations. The general principles for the application of colors to products are described with the overall aim of matching what the consumer expects from the particular food product.
Account must be taken of the effects of pH and processing, especially browning from the Maillard reaction and loss of initial color.
The influence of color on food acceptance
April 28, 2017
Characteristics and properties of carbohydrate
Carbohydrates are the main repository of photosynthetic energy in plants. They constitute roughly 50-80% of the dry matter of forages and cereals.
In living organism, they function as structural materials, energy reservesn, adhesives and information-transfer agents. Carbohydrate polymers derive from natur’s capacity to covert carbohydrate molecules into polyacetals by several pathways.
Polysaccharides–polysaccharides interaction plays an important role in the control of architecture of animal and plants cells.
The most important functional properties of food polysaccharides are water binding capacity and enhancing viscosity. As polysaccharides can dramatically increasing the solution viscosity at a relatively low concentration, they are often used as a viscofier in liquid and semisolid foods.
They are also used to stabilize food products such as emulsion, foam and frozen dairy products. The nutritive characteristics of carbohydrates depend on their sugar components and linkages with polyphenolic lignin and their physicochemical factors.
The most prominent character of carbohydrate metabolism is hyperglycemia which is speculated to be related it insulin resistance, due to counter regulatory hormones and mediators of inflammation; insulin resistance itself, however, does not explain this increase in glucose levels.
Characteristics and properties of carbohydrate
In living organism, they function as structural materials, energy reservesn, adhesives and information-transfer agents. Carbohydrate polymers derive from natur’s capacity to covert carbohydrate molecules into polyacetals by several pathways.
Polysaccharides–polysaccharides interaction plays an important role in the control of architecture of animal and plants cells.
They are also used to stabilize food products such as emulsion, foam and frozen dairy products. The nutritive characteristics of carbohydrates depend on their sugar components and linkages with polyphenolic lignin and their physicochemical factors.
The most prominent character of carbohydrate metabolism is hyperglycemia which is speculated to be related it insulin resistance, due to counter regulatory hormones and mediators of inflammation; insulin resistance itself, however, does not explain this increase in glucose levels.
Characteristics and properties of carbohydrate
January 18, 2017
Natural hard cheese
Natural hard cheeses get their taste, texture, and physical properties from high butterfat content, where the largest amount of fat and calories are contained.
A hard cheese, such as Cheddar, consists of roughly one-quarter protein, one-third fat and one-third water. Hard cheeses are largely free of additives. Processed cheese on the other hand, contains a variety of additives such as dried milk powder emulsifiers and flavors.
As researchers have worked to reduce the butterfat content in hard cheese analogs, a decrease in flavor and in melting properties has also occurred. Lack of flavor is sometimes offset by adding herbs, peppers or smoke flavoring.
Natural hard cheese can be stored for extended periods but quality eventually deteriorates as the proteolytic and lipolytic activities in the curd become excessive. Storage life can be improved by processing. Decomposition of proteins and lipids results in a nutritionally defective product unsuitable for consumption.
Most hard natural cheeses with low water content can be frozen for up to 2 months.
Natural hard cheese
A hard cheese, such as Cheddar, consists of roughly one-quarter protein, one-third fat and one-third water. Hard cheeses are largely free of additives. Processed cheese on the other hand, contains a variety of additives such as dried milk powder emulsifiers and flavors.
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| Cheddar cheese |
Natural hard cheese can be stored for extended periods but quality eventually deteriorates as the proteolytic and lipolytic activities in the curd become excessive. Storage life can be improved by processing. Decomposition of proteins and lipids results in a nutritionally defective product unsuitable for consumption.
Most hard natural cheeses with low water content can be frozen for up to 2 months.
Natural hard cheese
January 12, 2017
Nutritional properties of walnuts
The walnut is, together with other oil-bearing nuts, one of the most concentrated food sources of nutrients provided by nature.
Walnuts contain as high as 35 per cent moisture when harvested. They should be hulled, washed and dried as quickly as possible to 8 percent moisture or less and graded.
Fats
In walnuts fats are formed primarily of unsaturated fatty acids, with a preponderance of polyunsaturated in addition to lecithin.
With a 7:1 ratio of polyunsaturated to saturated fat, walnuts are one of the highest naturally occurring sources of polyunsaturated fats. Polyunsaturated fats are an important source of essential fatty acids.
Walnut also referred to as a brain food, it is rich in omega-3 fatty acids. Brain cells are made of fat. Hence, walnuts help providing ample nutrition to brain and flushing out toxic elements.
Carbohydrate
The walnut is the lowest of any-oil bearing nut in this nutrient (13.5%). Because of this, walnuts are well tolerated by diabetics.
Protein
Walnuts contain up to 14.3 of high quality protein, more than peanuts and about the same as almonds.
Vitamins
Walnuts are good sources of vitamins B1, B2, B3, E and particularly B6.
Minerals
Walnuts are rich in phosphorus, magnesium, copper, zinc and potassium, while they are low in sodium, which promotes cardiovascular health.
Walnuts contain several antioxidants including selenium, melatonin, gamma-tocopherols and several polyphenols.
They also contain 678 to 694 calories (kcl) for each 100g. Walnuts are high in calories primarily because they are about 60% fats.
Nutritional properties of walnuts
Walnuts contain as high as 35 per cent moisture when harvested. They should be hulled, washed and dried as quickly as possible to 8 percent moisture or less and graded.
Fats
In walnuts fats are formed primarily of unsaturated fatty acids, with a preponderance of polyunsaturated in addition to lecithin.
With a 7:1 ratio of polyunsaturated to saturated fat, walnuts are one of the highest naturally occurring sources of polyunsaturated fats. Polyunsaturated fats are an important source of essential fatty acids.
Walnut also referred to as a brain food, it is rich in omega-3 fatty acids. Brain cells are made of fat. Hence, walnuts help providing ample nutrition to brain and flushing out toxic elements.
Carbohydrate
The walnut is the lowest of any-oil bearing nut in this nutrient (13.5%). Because of this, walnuts are well tolerated by diabetics.
Protein
Walnuts contain up to 14.3 of high quality protein, more than peanuts and about the same as almonds.
Walnuts are good sources of vitamins B1, B2, B3, E and particularly B6.
Minerals
Walnuts are rich in phosphorus, magnesium, copper, zinc and potassium, while they are low in sodium, which promotes cardiovascular health.
Walnuts contain several antioxidants including selenium, melatonin, gamma-tocopherols and several polyphenols.
They also contain 678 to 694 calories (kcl) for each 100g. Walnuts are high in calories primarily because they are about 60% fats.
Nutritional properties of walnuts
November 18, 2015
Biology of xanthones
About 200 xanthones have been discovered. Xanthones are yellow pigments in flowers. Xanthones are flavonoids and are found in some fruit and bark of tree, but the highest concentration is found in the pericarp of the mangosteen fruit. Many are polyketide derived, although others are formed from combined shikimic acid pathways combined with acetate-malonate units.
Three units of malonate react with a hydroxybenzoic acid (C6-C1). Benzophenones may be converted by oxidative rings closure into xanthones.
Several xanthones that possess antidepressant activity inhibit monoamine oxidases. These compounds have in vitro cytotoxicity and in vivo antitumor activity. Xanthones kill microbes, improve depression, stimulate the production of urine and improve the function of the heart.
Xanthones derivatives occur in a number of higher plant families and fungi. Some fungal species are well known as sources of xanthone derivatives, for example, Penicilium raistrickii G. Sm, Phomopsis sp, and Humicola sp.
Biology of xanthones
Three units of malonate react with a hydroxybenzoic acid (C6-C1). Benzophenones may be converted by oxidative rings closure into xanthones.
Several xanthones that possess antidepressant activity inhibit monoamine oxidases. These compounds have in vitro cytotoxicity and in vivo antitumor activity. Xanthones kill microbes, improve depression, stimulate the production of urine and improve the function of the heart.
Xanthones derivatives occur in a number of higher plant families and fungi. Some fungal species are well known as sources of xanthone derivatives, for example, Penicilium raistrickii G. Sm, Phomopsis sp, and Humicola sp.
Biology of xanthones
June 9, 2015
Alpha-cyclodextrin
Alpha-cyclodextrin occurs as a virtually odorless, white or almost white crystalline solid. It is tasteless, resistant to heat, stable at pH levels generally encountered in food manufacture and able to perform inclusion complexes with appropriately sized non-polar organic compounds.
Alpha-cyclodextrin contains six glucopyranosyl units linked by α -1, 4-glycosidic bonds and is one of a family of three cyclodextrin molecules (α-, β - and γ–cyclodextrin).
In nature, the cyclodextrins are produced as a storage form of carbohydrate by some microorganisms, but they can also be produced industrially by the enzymatic degradation of amylose by cyclodextrin-glucoltransferases, a group of amylolytic enzymes, belonging to class of α–amylases.
The properties of alpha-cyclodextrin have allowed it to be used as a carrier for the range of flavour, colors, sweeteners and fatty acids.
It is used as encapsulating agent and stabilizer. It provides exceptional protection to enclosed favors in terms of evaporation loss and oxidation.
Alpha-cyclodextrin
Alpha-cyclodextrin contains six glucopyranosyl units linked by α -1, 4-glycosidic bonds and is one of a family of three cyclodextrin molecules (α-, β - and γ–cyclodextrin).
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| Alpha-cyclodextrin |
The properties of alpha-cyclodextrin have allowed it to be used as a carrier for the range of flavour, colors, sweeteners and fatty acids.
It is used as encapsulating agent and stabilizer. It provides exceptional protection to enclosed favors in terms of evaporation loss and oxidation.
Alpha-cyclodextrin
September 28, 2014
Properties of beef fat
Considerable variation occurs in the fatty acid composition of animal fat triglycerides. The variation is fatty acid composition for similar animal species is a function of diet, location of fat recovery from animal carcass and environment. It is also affected by the kind and breed of animal and by the feed.
Edible beef fat is obtained from bovine adipose tissue covering the abdominal cavity and surrounding the kidney and heart and from other compact, undamaged tissue.
The beef fat is light yellow due to carotenoids derived from animal feed. It is of a friable, brittle consistency and melts between 45 and 50°C.
The majorities of the fatty acid chains are 14 to 18 carbons in length and are both saturated and unsaturated.
Live animal fat tissue contains virtually no free fatty acid. Upon slaughter, enzyme action is activated which results in rapid hydrolysis of the animal fat. Most of the wide range in total fat composition of beef carcasses is caused by trimmable fat and much of it is removed in preparing retail cuts.
The beef fat when heated yields two fractions: oleomargarine (liquid) and oleostearine (solid). Oleomargarine is a soft fat with a consistency similar to that of melted butter.
Properties of beef fat
Edible beef fat is obtained from bovine adipose tissue covering the abdominal cavity and surrounding the kidney and heart and from other compact, undamaged tissue.
The beef fat is light yellow due to carotenoids derived from animal feed. It is of a friable, brittle consistency and melts between 45 and 50°C.
The majorities of the fatty acid chains are 14 to 18 carbons in length and are both saturated and unsaturated.
Live animal fat tissue contains virtually no free fatty acid. Upon slaughter, enzyme action is activated which results in rapid hydrolysis of the animal fat. Most of the wide range in total fat composition of beef carcasses is caused by trimmable fat and much of it is removed in preparing retail cuts.
The beef fat when heated yields two fractions: oleomargarine (liquid) and oleostearine (solid). Oleomargarine is a soft fat with a consistency similar to that of melted butter.
Properties of beef fat
June 23, 2014
Saturated fatty acid: Capric acid
Capric acid was discovered by Chevreul in 1818, at the same time with caproic: and the name was also derived from copra.
This acid is formed with many others from butter and goats’ fat. It is also produced by the oxidation of the oil of rue.
Capric acid is also contained in small quantity in the fatty acids of the coconut oil. Capric acid has been added to the list of coconut’s antimicrobial components.
Capric acid is solid, and has the shape of colorless needles at the temperature of 62 °F. At 64°F it melts into transparent colorless liquid resembling a volatile oil. It specific gravity at 64 °F is 0.9103.
This acid is sparingly soluble in boiling water, but it separates completely, in glistening plates, as the liquid cools; its taste is sour and burning.
Capric acid is generally purified by causing it to combine with Barium hydroxide: the salt thus obtained crystallizes in brilliant plates.
The acid is used, among other things, in the manufacture of esters for fruit flavor.
Saturated fatty acid: Capric acid
This acid is formed with many others from butter and goats’ fat. It is also produced by the oxidation of the oil of rue.
Capric acid is also contained in small quantity in the fatty acids of the coconut oil. Capric acid has been added to the list of coconut’s antimicrobial components.
Capric acid is solid, and has the shape of colorless needles at the temperature of 62 °F. At 64°F it melts into transparent colorless liquid resembling a volatile oil. It specific gravity at 64 °F is 0.9103.
This acid is sparingly soluble in boiling water, but it separates completely, in glistening plates, as the liquid cools; its taste is sour and burning.
Capric acid is generally purified by causing it to combine with Barium hydroxide: the salt thus obtained crystallizes in brilliant plates.
The acid is used, among other things, in the manufacture of esters for fruit flavor.
Saturated fatty acid: Capric acid
May 15, 2014
Properties of vitamin K
Vitamin K comprises derivatives of 1,4-naphthiquinone. Naturally occurring forms are equipped with structures possessing the unsaturated isoprenoid side chain linked to naphthoquinones at carbon-3.
Vitamin K also fat soluble. It is essential for the synthesis of prothrombin a compound involved in the clotting of blood.
Vitamin K is mostly needed to help to stop bleeding, but it has some other jobs as well.
It is a cofactor specific to the formation of –carboxyglutamyl residues from specific glutamate residues in certain proteins.
The most important is the crucial role vitamin K, plays building bones. Vitamin K is needed to help hold onto the calcium in bones and make sure it’s getting to the right place.
It actually comes in three different forms: First, there’s vitamin K1, or phylloquinone. This is the form of vitamin K found in plant foods.
Vitamin K1 is quite stable to oxidation and most food processing and food preparation procedures. It is unstable to light and alkaline conditions.
Next, there’s Vitamin K2, also called menaquinone. This the form friendly bacteria in the intestines make.
The last form would be called vitamin K3. It is also called menadione. Menadione is the only formed isolated from Staphylococcus aureus and also chemically synthesized. It is a synthetic compound that can be converted into K2 in the gastrointestinal tract.
All your vitamin K ends up in liver, where it’s used to make some of the substance that make blood clot.
Properties of vitamin K
Vitamin K also fat soluble. It is essential for the synthesis of prothrombin a compound involved in the clotting of blood.
Vitamin K is mostly needed to help to stop bleeding, but it has some other jobs as well.
It is a cofactor specific to the formation of –carboxyglutamyl residues from specific glutamate residues in certain proteins.
The most important is the crucial role vitamin K, plays building bones. Vitamin K is needed to help hold onto the calcium in bones and make sure it’s getting to the right place.
It actually comes in three different forms: First, there’s vitamin K1, or phylloquinone. This is the form of vitamin K found in plant foods.
Vitamin K1 is quite stable to oxidation and most food processing and food preparation procedures. It is unstable to light and alkaline conditions.
Next, there’s Vitamin K2, also called menaquinone. This the form friendly bacteria in the intestines make.
The last form would be called vitamin K3. It is also called menadione. Menadione is the only formed isolated from Staphylococcus aureus and also chemically synthesized. It is a synthetic compound that can be converted into K2 in the gastrointestinal tract.
All your vitamin K ends up in liver, where it’s used to make some of the substance that make blood clot.
Properties of vitamin K
March 15, 2014
Nutritional properties of dietary fats
Dietary fat is human second most important energy-producing macronutrient. It also contains fatty acids and vitamins essential for growth, development and maintenance of good health.
It has been reported that a lean man of 70kg is made up of water (60%), protein (17%), fat (12 kg or 17%) and a balance (6%) which includes glycogen and bone.
Dietary fat is an important caloric source for human metabolism and the major substrate that keeps human alive during most of each day.
It is widely available and efficient source of energy at 9 cal/g compared with only 4 for carbohydrate and protein and can be turn onto energy with only minimal metabolic modification.
The average daily intake of fat in a western diet ranges between 50 to 100 g and provides between 35% and 40% of total energy.
For daily intake of 2000 kcals, 67 g or fat corresponds to 30 per cent of total energy. Level of 35 per cent and 40 per cent of total energy correspond to daily fat intakes of 78g and 89 g respectively.
Dietary fat consists mainly of triacylglycerol (TAG), which forms the principal component of visible oils and fats, and minor quantities of phospholipids and cholesterol esters.
Dietary fats are derived from both plant and animal sources and are classified as ‘visible’ or ‘invisible’ types, fats that are used as such at the table or for cooking (vegetable oils, vanaspati, butter and ghee) are termed ‘visible’ fats.
Fats that are present as an integral component of different foods are referred to as ‘invisible’ fat.
The physical properties of dietary fat, such as their hardness at room temperature (melting point) and subsequent metabolic properties once in the body, are determined by the number of double bonds in their constituent fatty acid, (degree of saturation or unsaturation) and length of the fatty acid carbon chain.
Nutritional properties of dietary fats
It has been reported that a lean man of 70kg is made up of water (60%), protein (17%), fat (12 kg or 17%) and a balance (6%) which includes glycogen and bone.
Dietary fat is an important caloric source for human metabolism and the major substrate that keeps human alive during most of each day.
It is widely available and efficient source of energy at 9 cal/g compared with only 4 for carbohydrate and protein and can be turn onto energy with only minimal metabolic modification.
The average daily intake of fat in a western diet ranges between 50 to 100 g and provides between 35% and 40% of total energy.
For daily intake of 2000 kcals, 67 g or fat corresponds to 30 per cent of total energy. Level of 35 per cent and 40 per cent of total energy correspond to daily fat intakes of 78g and 89 g respectively.
Dietary fat consists mainly of triacylglycerol (TAG), which forms the principal component of visible oils and fats, and minor quantities of phospholipids and cholesterol esters.
Dietary fats are derived from both plant and animal sources and are classified as ‘visible’ or ‘invisible’ types, fats that are used as such at the table or for cooking (vegetable oils, vanaspati, butter and ghee) are termed ‘visible’ fats.
Fats that are present as an integral component of different foods are referred to as ‘invisible’ fat.
The physical properties of dietary fat, such as their hardness at room temperature (melting point) and subsequent metabolic properties once in the body, are determined by the number of double bonds in their constituent fatty acid, (degree of saturation or unsaturation) and length of the fatty acid carbon chain.
Nutritional properties of dietary fats
January 7, 2009
The meaning of ‘shortenings’
The meaning of ‘shortenings’
Fats and fat products may consist of:
Fat products are used as shortenings, spreads, solid oil, cooking and frying fats and oils, and in the preparations of confectionery and icings.
The term shortening had its origin in the United States and referred to a preparation, originally developed from cottonseed oil, that was used to “shorten” the preparation time of shortbread and cakes. Shortenings consist entirely of fat and contain no moisture. The traditional shortening is lard.
Domestic shortenings generally fall into one of two categories – molded products (10% air) and liquid filled products (10 – 35% air). Molded products have goods cake making properties. Liquid-filled products are more expensive but are easier to use.
Shortenings are matured (tempered) by holding at an elevated temperature (25 – 30%) for up to 48 hr. This maturation causes a change in crystal structure such that when the product is cooled it has a plastic texture. This process is accomplished with scraped surface heat exchangers.
High ratio shortenings allow a higher ratio of sugar to flour to be used in cakes due to the emulsifying properties of the shortenings. Emulsifiers are usually mono – or diglycerides.
The meaning of ‘shortenings’
Fats and fat products may consist of:
- Fat or oil
- Fat plus an emulsifying agent
- Fat emulsions such as butter and margarine
Fat products are used as shortenings, spreads, solid oil, cooking and frying fats and oils, and in the preparations of confectionery and icings.The term shortening had its origin in the United States and referred to a preparation, originally developed from cottonseed oil, that was used to “shorten” the preparation time of shortbread and cakes. Shortenings consist entirely of fat and contain no moisture. The traditional shortening is lard.
Domestic shortenings generally fall into one of two categories – molded products (10% air) and liquid filled products (10 – 35% air). Molded products have goods cake making properties. Liquid-filled products are more expensive but are easier to use.
Shortenings are matured (tempered) by holding at an elevated temperature (25 – 30%) for up to 48 hr. This maturation causes a change in crystal structure such that when the product is cooled it has a plastic texture. This process is accomplished with scraped surface heat exchangers.
High ratio shortenings allow a higher ratio of sugar to flour to be used in cakes due to the emulsifying properties of the shortenings. Emulsifiers are usually mono – or diglycerides.
The meaning of ‘shortenings’
October 20, 2008
Food Texture
Food Texture
Texture refers to those qualities of a food that can be felt with the fingers, tongue, palate, or teeth. Foods have different textures, such as crisp crackers or potato chips, crunchy celery, hard candy, tender steaks, chewy chocolate chip cookies and creamy ice cream, to name but a few.
Texture is also an index of quality. The texture of a food can change as it is stored, for various reasons. If fruits or vegetables lose water during storage they wilt or lose their turgor pressure, and a crisp apple becomes unacceptable and leathery on the outside.
Bread can become hard and stale on storage. Products like ice cream can become gritty due to precipitation of lactose and growth of ice crystal in the freezer temperature is allowed to fluctuate, allowing thawing and refreezing.
Evaluation of texture involves measuring the response of a food when it is subjected to forces such as cutting, shearing, chewing, compressing or stretching. Food texture depends on the rheological properties of the food. Rheology is defined as the science of deformation and flow of matter or in other words, reaction of a food when a force is applied to it.
Does it flow, bend, stretch or break? From a sensory perspective, the texture of a food is evaluated when it is chewed. The teeth, tongue and jaw exert a force on the food, and how easily it breaks or flows in the mouth determines whether it is perceived as hard, brittle, thick, runny, and so on. The term mouthfeel is a general term used to describe the textural properties of a food as perceived in the mouth.
Food Texture
Texture refers to those qualities of a food that can be felt with the fingers, tongue, palate, or teeth. Foods have different textures, such as crisp crackers or potato chips, crunchy celery, hard candy, tender steaks, chewy chocolate chip cookies and creamy ice cream, to name but a few.
Texture is also an index of quality. The texture of a food can change as it is stored, for various reasons. If fruits or vegetables lose water during storage they wilt or lose their turgor pressure, and a crisp apple becomes unacceptable and leathery on the outside.
Bread can become hard and stale on storage. Products like ice cream can become gritty due to precipitation of lactose and growth of ice crystal in the freezer temperature is allowed to fluctuate, allowing thawing and refreezing.
Evaluation of texture involves measuring the response of a food when it is subjected to forces such as cutting, shearing, chewing, compressing or stretching. Food texture depends on the rheological properties of the food. Rheology is defined as the science of deformation and flow of matter or in other words, reaction of a food when a force is applied to it.
Does it flow, bend, stretch or break? From a sensory perspective, the texture of a food is evaluated when it is chewed. The teeth, tongue and jaw exert a force on the food, and how easily it breaks or flows in the mouth determines whether it is perceived as hard, brittle, thick, runny, and so on. The term mouthfeel is a general term used to describe the textural properties of a food as perceived in the mouth.
Food Texture
August 7, 2006
Food Proteins
Protein constitutes 10-15 per cent of the energy in almost all human diets. It is also important in the structure of all cells in the body, as well as forming enzymes, molecules that transport substances in the blood and some hormones.
The problem of providing adequate protein for an expanding world population is a second only to the overall food problem.
Apart from their nutritional significance, proteins play a large part in the organoleptic properties of foods.
Proteins exert the controlling effect on a texture of foods from animal sources.
Foods in meat, poultry, dry peas and beans, eggs, ad nuts group and in the milk, yoghurt and cheese group contribute an abundance of high quality protein.
Two others, the vegetable group and the grains group, contribute smaller amounts of protein, but they can add up to significant quantities.
Protein content of wheat and flour is considered one of the best single indices of bread making quality.
Protein often occurs in foods in physical or chemical combinations with carbohydrates and lipids.
The glycol proteins and lipoproteins affect the rheological properties of food solution or have technical applications as edible emulsifiers.
During the heating (boiling, baking or roasting) the amino acid side chains are degraded or interact with other food component (e.g. lysine with reducing sugar) to give typical flavor.
Excessive heating may, on the other hand, reduce nutritive value.
The protein quality of the diet determines, in large part, how well children grow and how well adults maintain their health.
High quality protein provide enough of all the essential amino acids needed to support the body’s work, and low quality proteins do not.
Two factors influence protein quality – the protein’s digestibility and its amino acid composition.
Food Proteins
The problem of providing adequate protein for an expanding world population is a second only to the overall food problem.
Apart from their nutritional significance, proteins play a large part in the organoleptic properties of foods.
Proteins exert the controlling effect on a texture of foods from animal sources.
Foods in meat, poultry, dry peas and beans, eggs, ad nuts group and in the milk, yoghurt and cheese group contribute an abundance of high quality protein.
Two others, the vegetable group and the grains group, contribute smaller amounts of protein, but they can add up to significant quantities.
Protein content of wheat and flour is considered one of the best single indices of bread making quality.
Protein often occurs in foods in physical or chemical combinations with carbohydrates and lipids.
The glycol proteins and lipoproteins affect the rheological properties of food solution or have technical applications as edible emulsifiers.
During the heating (boiling, baking or roasting) the amino acid side chains are degraded or interact with other food component (e.g. lysine with reducing sugar) to give typical flavor.
Excessive heating may, on the other hand, reduce nutritive value.
The protein quality of the diet determines, in large part, how well children grow and how well adults maintain their health.
High quality protein provide enough of all the essential amino acids needed to support the body’s work, and low quality proteins do not.
Two factors influence protein quality – the protein’s digestibility and its amino acid composition.
Food Proteins
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