Notes

Why refined grains are bad for us and how they can affect our health?

For many years now, we have heard nutritionists and health professionals all over the world say that we should limit the intake of refined grains as they are bad for us. Or they say that we should replaced refined grains with whole grains due to higher incidence of diet related illnesses such as diabetes, obesity and heart diseases. But have you ever wondered as why is that so? Why are refined grains bad for us and how they can affect our health?

Eating healthy and nutritious foods is very important for good health. Despite being consumed widely, the health effects of grains are still to be known clearly as some people believe they are healthy whereas some believe them to be harmful for us. So, a clear understanding is very important and this article will provide you an insight into refined grains and how they are different from the whole grains and what effects they have on our health? Read more

Post Harvest of Cacao Beans

Cacao beans are the seed obtained from the pods of the plant Theobroma cacao tree. The processing of cacao beans to obtain cocoa liquor and cocoa butter and cocoa powder includes series of steps of processing.

Fig: A whole cacao pod (a), an open cacao pod before fermentation (b), fermented cacao beans (c), toasted cacao nibs (d), chocolate discs (e) [Source: https://i.pinimg.com /736x/f9/cb/93/f9cb9332834d21fd3464bcf2c9e473de.jpg
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FACTORY HYGIENE AND CONVEYOR BELTS

The world is undergoing a significant increase in its industrialized food processing, and this has entailed a close examination of all aspects of modern hygienic food processing. This involves more investment in machinery and while factory owners may only consider saving of time, space and money and the wish to increase output to serve a wider market, there is another consideration, which is the increased risk of food-borne illnesses and the sometimes unbearably high costs of rectifying this post facto.

There are many systems used to eliminate or reduce the risks of contamination which begin with the raw materials from the farm and field and continue throughout the process until packing. Some risks can be eliminated once and for all, such as small stones and insects washed out of a vegetable harvest but there are far more dangerous forms of contamination further down the line before packing, including inside the factory. Read more

Identifying Characteristics of Yeast, Mold, Protozoa and Rickettsia

Yeast:

Yeast are group of non-mycelial unicellular fungi belonging to the group Ascomycetes. They are cosmopolitian fungi which occur in almost all places of the world having organic matter, especially sugars. Most of the species are saprophytes. They grow on the nectar of flowers, surface of sweet fruits, sugarcane, milk and other food stuffs, animal excreta, humus of soil etc.

In general, yeast cells are longer than most bacteria. Yeast vary considerably in size ranging from one to five μm in width and from 5 to 30 μm or more in length. They are commonly egg shaped but are sometimes lemon shaped, pear shaped or elongated into false or true mycelium. Yeast have no flagella and other organelles of locomotion. Read more

Bacterial Structures Internal to Cell Wall and Reproduction

The bacterial structures internal to cell wall includes cytoplasmic membrane, protoplast, spheroplast, spores, plasmid and others.

Fig: Structure of bacteria (https://clinicalgate.com/wpcontent/ uploads/2015/ 02/B9780323069380000062_gr2.jpg )

Cytoplasmic membrane: This is a thin structure that completely surrounds the cell. Its size is approximately 7.5 nm in thickness and is composed primarily of phospholipid (20 – 30 %), protein (60 – 70 %). The phospholipid form bilayered structure in which most of the protein are embedded tightly called integral protein. This protein can only be removed by destruction of the membrane with treatment such as with detergent. Other protein which are loosely attached are called peripheral protein. This peripheral protein can be easily removed mild treatment such as osmotic shock. Read more

Morphology of Bacteria and its Structures External to Cell Wall

The morphology of bacterial cell includes characteristics such as size, shape, structure etc. First of all, Leeuwenhoek revealed the gross appearance of microorganism including bacteria by light microscope. By the discovery of electron microscope in early 1940’s the study of structural bacterial cell has been made very easier. The morphological characteristic of a bacterial cell is as follows.

Size: Bacteria vary in size from cell to cell. It can be as small as 0.1 to 0.2 μm in width to as large as more than 50 μm in diameter. A few very large prokaryotes such as Epulopiscium fishelsoni [1] that inhabits the intestinal tract of Surgeon fish  are up to 50 μm in diameter and can be more than 0.5 mm in length. However, the dimension of an average rod cell prokaryotes E.coli are about 1×3 μm. Read more

Comparison of Refrigerants and its Ideal Properties

For refrigerants to be ideal, it should possesses following properties
1. Low boiling point
2. Low freezing point
3. High critical pressure and temperature (to avoid large power requirement)
4. Low specific heat (high specific heat decreases refrigerant effect per kg or refrigerant.
5. High latent heat (increases refrigerant effect per kg of refrigerant)
6. Pressure in evaporator and condenser should be low enough to reduce material cost and must be positive to avoid leakage of air into the system.
7. Low specific volume to reduce size of compressor.
8. High thermal conductivity to reduce area of heat transfer in evaporator and condenser.
9. Non-flammable, non-explosive, non-toxic and non-corrosive.
10. High miscibility with lubricating oil and should not have reacting property with lubricating oil in the temperature range of system.
11. High coefficient of performance (COP) to reduce cost of system
12. Readily available and cheap Read more