Meet the Organic Molecules in Organic Foods

We all have to eat! But how much do we really know about the chemistry of food?

While chemistry has been a great benefit to us, sometimes in the form of chemical pesticides and fertilizers causing health hazards.

One step towards the solution is growing more organic food / greener food.

After knowing what organic food is, we should know about

Food chemistry and

Organic molecules

Organic Food

Organic food, defined by how it cannot be made rather than how it can be made, must be produced without the use of sewer-sludge fertilizers, most synthetic fertilizers and pesticides, genetic engineering (biotechnology), growth hormones, irradiation and antibiotics. “Organic” does not mean “natural.” There is no legal definition as to what constitutes a “natural” food. However, the food industry uses the term “natural” to indicate that a food has been minimally processed and is preservative-free.

India started the ‘Green Revolution’ in the 1960s. During this time, the amount of food that could be grown in every acre of land increased manifold through the use of pesticides and fertilizers. However, these have many dangerous side-effects. Chemical pesticides not only kill harmful insects like weevils and borers, but also beneficial insects like butterflies and bees. Many plants depend on these insects for their pollination and seed dispersal. These pesticides do not break down, but accumulate in the plants. This can lead to a dangerous build up that causes harmful health effects in people who eat these foods. Fertilizers have a similar effect. They were originally used to provide nutrients to crop plants that were not present in enough quantities in the soil. However, over time fertilizers lead to the quality of the soil becoming worse, till it is unable to support agriculture.

Organic food differs from conventionally produced food simply in the way it is grown, handled and processed. A recently published report indicates that organic food is less likely to contain pesticide residues than conventional food (13 percent of organic produce samples versus 71 percent of conventional produce samples contained a pesticide residue when long-banned persistent pesticides were excluded). Yet, according to the National Research Council, the traces of pesticides left on conventionally grown products are unlikely to cause an increased cancer risk. Also, if fruits and vegetables are properly washed, most of the chemicals can be removed.

A 2014 meta-analysis of 343 studies, found that organically grown crops had higher concentrations of antioxidants, containing 17% more antioxidants overall compared to conventionally grown crops. Concentrations of phenolic acids, flavanones, stilbenes, flavones, flavonols, and anthocyanins were particularly elevated, with flavanones being 69% higher.

A 2012 survey of the scientific literature reported ascorbic acid (Vitamin C), beta-carotene (a precursor for Vitamin A), and alpha-tocopherol (a form of Vitamin E) content; milk studies reported on beta-carotene and alpha-tocopherol levels in organic food.

Food chemistry is the study of chemical processes and interactions of all biological and non-biological components of foods. It is similar to biochemistry in its main components such as carbohydrates, lipids, and protein, but it also includes areas such as water, vitamins, minerals, enzymes, food additives, flavors, and colors. This discipline also encompasses how products change under certain food processing techniques and ways either to enhance or to prevent them from happening.

Basic food chemistry deals with the organic molecules. Organic molecules are nothing but the chemicals of life, compounds that are composed of more than one type of element. Organic molecules are found in, and are produced by living organisms. The feature that distinguishes an organic molecule from inorganic molecule is that the organic molecules contain carbon-hydrogen bonds whereas the inorganic molecules do not.

The four major classes of organic molecules include carbohydrates, proteins, lipids and nucleic acids.

Carbohydrates

Carbohydrates molecules contain carbon hydrates in a ratio of one carbon molecule to one water molecule (CH2O).

There are different types of carbohydrates as well. This includes

  • Saccharide
  • Monosaccharides
  • Polysaccharides

The word saccharide is another word for carbohydrate, because it can be preceded with a prefix that indicates the size of the molecule (mono-, di-, tri- poly-).

Monosaccharides are the simplest form of molecules as they contain single sugars and have just one molecule. Disaccharides are double sugars and are a combination of two monosaccharides. Polysaccharides are polymers and are composed of several sugars. They can be same monomer (many of same monosaccharide) or mixture of monomers.

Proteins

Proteins are polymers, and their building blocks are amino acids. Each amino acid contains

  • Base amino group (-NH2)
  • Acidic carboxyl group (-COOH)
  • Hydrogen atom

All of the above are attached to same carbon atom (the α-carbon or alpha carbon). A fourth bond attaches an alpha carbon to a side group that varies among different amino acids. These side groups are important, as they affect the way the protein’s amino acids interact with one another, and how a protein interacts with other molecules. Alhough there are hundreds of different amino acids, most organisms use only 21 to build proteins.

Peptide bonds are the covalent bonds which link amino acids into chains and they look like the beads on a necklace. A dipeptide is two amino acids that are linked together and a polypeptide is the one that is more than two.

Lipids

Lipids are molecules that are hydrophobic and are not attracted to water because the non-polar covalent bonds that link carbon and hydrogen are not attracted to the polar bonds of water. The four major groups of lipids include

  • Fats
  • Phospholipids
  • Waxes
  • Steroids

Fats

Fats and oils are made from two kinds of molecules — glycerol which is a type of alcohol and three fatty acids which are also known as triglycerides.

Phospholipids

The structure of this type of lipid includes a hydrophobic or a “water hating,” hydrocarbon tails and hydrophilic or a water loving phosphate groups on the end. This means that phospholipids are soluble in both water and oil.

Our body cell membranes are made mostly of phospholipids that are arranged in a double layer with the tails from both layers facing inward and the heads facing outward. This is called as lipid bilayer.

Waxes

Waxes are esters of alcohol which are insoluble in water and are difficult to break down. Wax forms protective and waterproof layers on some plants, bacteria, animal fur and integuments of insects.

Steroids

Steroids form the central core of a cholesterol molecule which consists of four fused rings and is shared by all steroids. Cholesterol is a precursor to our sex hormones and Vitamin D. Our cell membranes contain a lot of cholesterol which helps in keeping the membrane flexible and fluid even when our cells are exposed to cooler temperatures.

Nucleic Acids and Nucleotides

Nucleic acids are polymers that are made up of nucleotide monomers. Each monomer of nucleic acid is a nucleotide and consists of three portions; pentose sugar, one or more phosphate groups and one of five cyclic nitrogenous bases.

Nucleotides are linked by covalent bonds between phosphate of one nucleotide and sugar of next, thereby forming a phosphate-sugar backbone. The nitrogenous bases extend from it like teeth of a comb.

Hydrogen bonds form between specific bases of two nucleic acid chains, forming a stable, double-stranded DNA molecule. Hydrogen bonding twists the phosphate-deoxyribose backbones into a helix giving it a typical DNA double helix.

Adenosine 5'-triphosphate or ATP, also known as the energy transfer molecule is a multifunctional nucleotide and is important for the “molecular currency” of intracellular energy transfer. ATP transports chemical energy within cells for metabolism.

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Originally published at www.worldofchemicals.com.