(MSCDFSM) Food Microbiology and Safety (TMA-3) ANSWER 2017

Q2. Describe the relationship between the following sets of terms:

a) Lathyrism and Food adulteration

b) pH and Spoilage of Meat

c) Vacuum packaging and Extended shelf life of food

d) Canning and Food Preservation

e) Toxic heavy metal and Food chain.

ANS- Lathyrism and Food adulteration— Lathyrism is a disease caused by eating seeds of species of Lathyrus (the grass pea), mainly L. sativus (the chickpea or khesari), L. cicera (flat-podded vetch) and L. clymenum (Spanish vetchling). It affects mostly people in Bangladesh, India, Pakistan, Nepal and Algeria but is sometimes found in France, Italy, Spain and Australia. This disease affects horses and cattle as well as in man. Beta-oxalyl-amino-L-alanine acid (BOAA), an excitatory neurotoxin and glutamate agonist, has been identified as the constituent of the chickling pea responsible for the disease. BOAA appears to exert its effects through mitochondrial toxicity.

Food adulteration is the process in which the quality of food is lowered either by the addition of inferior quality material or by extraction of valuable ingredient. It not only includes the intentional addition or substitution of the substances but biological and chemical contamination during the period of growth,

ANS(B)-  pH (potential of hydrogen) is a scale of acidity from 0 to 14. It tells how acidic or alkaline a substance is. More acidic solutions, have lower pH. More alkaline solutions, have higher pH.

Bacterial spoilage of meat and cured meat products. ... The predominant bacteria associated with spoilage of refrigerated beef and pork, are Brochothrix thermosphacta, Carnobacterium spp., Enterobacteriaceae, Lactobacillus spp., Leuconostoc spp., Pseudomonas spp. and Shewanella putrefaciens.

ANS(C)- Vacuum packaging is another way to increase the shelf life of food products. Here the product is placed in an air-tight pack, the air sucked out and the package sealed. By removing air from around the product, the levels of oxygen in the packaging are reduced, impeding the ability of oxygen-breathing microorganisms to grow and spoil the product. The lack of oxygen also reduces the amount of spoilage due to oxidation

Extended shelf life refrigerated foods are foods that have received minimal processing or precooking and have an enhanced but limited shelf life; refrigeration is a key preservation measure. These foods include conventional products, such as luncheon meats and cured meats, as well as a new generation of partially processed refrigerated foods (NFPA, 1988) such as meat, seafood, egg,

ANS(D)- Canning is an important, safe method for preserving food if practiced properly. The canning process involves placing foods in jars or similar containers and heating them to a temperature that destroys micro-organisms that cause food to spoil. During this heating process air is driven out of the jar and as it cools a vacuum seal is formed. This vacuum seal prevents air from getting back into the product bringing with it contaminating micro-organisms.

Food preservation involves preventing the growth of bacteria, fungi (such as yeasts), or other micro-organisms (although some methods work by introducing benign bacteria or fungi to the food), as well as slowing the oxidation of fats that cause rancidity.

ANS(E)- Heavy metals (including lead, cadmium, mercury, and the metalloid arsenic) are persistent in the environment and have documented potential for serious health consequences. Heavy metal toxicity may damage: central nervous system. cardiovascular system.

A food chain is the sequence of who eats whom in a biological community (an ecosystem) to obtain nutrition. A food chain starts with the primary energy source, usually the sun or boiling-hot deep sea vents. The next link in the chain is an organism that make its own food from the primary energy source -- an example is photosynthetic plants that make their own food from sunlight (using a process called photosynthesis) and chemosynthetic bacteria that make their food energy from chemicals in hydrothermal vents. These are called autotrophs or primary producers.