Month: June 2020

Jun 30

Why Functional foods are high valued?

Food with ingredient that are medically beneficial beyond their basic nutritional value are called functional food. It is similar in appearance to conventional food, consumed part of normal diet and has demonstrated physiological benefit and reduces the risk of chronic disease beyond basic nutritional function. Examples include tomatoes, broccoli, citrus fruits, leafy vegetables and many more. People are starting to look at food as a perception for health. Functional food in highest demand include those containing omega -3 fatty acid, glucosamine and probiotics.

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Jun 29

Control of ripening of fruits and vegetables

Ripening process need to be controlled during handling and storage of fruits and vegetables. Ripening process need to be hastened when there is high demand in the market and ripening process need to be controlled or delayed when there is no demand in the market. Precooling, Changes in atmospheric composition, temperature manipulation, hypobaric storage and irradiation are common practices in controlling the ripening process.

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Jun 28

Climacteric fruits and Ethylene

Climacteric fruit normally ripe after harvest, have higher ethylene production rate response with applied ethylene and result faster and more uniform ripening. Example; mango, apricot, banana, kiwi fruit, avocado, tomato etc. Therefore, climacteric fruits are commercially harvested at their maturity stage before onset of ripening to prevent damage and injury during handling and storage. In other hand, non-climacteric fruits do not ripe if they are harvested before they are ripen. Read more

Jun 27

Fruits and Vegetables : Introduction

A fruit is a seed bearing part of plant and is edible when ripen and fleshy. Many vegetables may be considered fruit in the true botanical sense. Botanically, fruits are those portion of plant which house seeds. Therefore, items such as tomatoes, cucumber, peppers etc. would be classified as fruit on this basis. However, important distinction between fruit and vegetable lies on usage basis. Those items that are generally eaten with main course of meal are considered vegetables. Those that are commonly eaten as deserts are considered fruits. Vegetables are derived from different parts of the plants. Read more

Jun 27

Minimum Reflux (infinite no. of plates)

At any reflux less than total, the number of plates needed for given separation is larger than total reflux. The number of plate increases continuously as reflux ratio is decreased. As the ratio becomes smaller, no. of plates required becomes very large and at definite minimum reflux ratio, number of plate become infinite.

This minimum reflux ratio can be defined as the reflux ratio (Rm) that will require infinite no. of trays for given desired separation of XD and XB. This corresponds to minimum vapor flow in tower and hence minimum reboiler and condenser sizes. Read more

Jun 26

Total Reflux (minimum no. of plates)

The total reflux condition represents operation with no product removal. All the overhead product is condensed and returned as reflux. Consequently D = 0 and reflux ratio becomes infinite. (RD = L/D = ∞). This in turn, makes the operating line, 45° line where V = L and slope = 1. The operating line then coincides with diagonal. This condition is called total reflux. Read more