SCIENCE is life

What is biogas? Biogas is a mixture of gases produced as anaerobic bacteria break down organic matter. It is a renewable gaseous fuel containing approximately 50-70% methane and 30-40% carbon dioxide. Biogas is produced as a by product from the decomposition of organic waste in landfills and anaerobic digesters that process agricultural waste and municipal waste water.  Biogas is produced by bacteria through the biodegration of organic material under anaerobic condition. Natural generation of biogas is an important part of biogeochemical carbon cycle. It can be used both in rural and urban areas. Anaerobic digestion of animal manure and other agricultural waste offers a number of additional benefits to farmers, including reduced air and water pollution, odor management, production of environmentally benign co-products including organic fertilizer and animal bedding material, new revenue streams such as sales of renewable natural gas and more environmentally frie...

Alot of products are derived from livestock, both edible and inedible, for this discourse, we look at the edible products. The edible products include,  milk, meat eggs. Milk processing Milk is the lacteal secretion from the mammary gland of females livestock. Although in modern days, milk can also be gotten from plants eg soybean milk, coconut milk. The milk from animals from cow, goat, buffallo etc. The milk is a very good vehicle for transmission of pathogens so milk handlers should exercise the utmost level of personal hygiene, the milk processing area should be sanitized. The milk handlers must be free from gastro-intestinal infections, no coughing, sneezing, diarrhoea etc. Note that the dairy animals are kept in hygienic condition, sick or animals receiving treatment should not be milk. The udders should be washed prior to milking in order to reduce the risk of contamination of the milk. Once milk is collected from the animals through a milking machine, the t...

The word cell , comes from the latin word, ' cellula ' meaning a small room or a monk's tiny bare room. This descriptive name, was chosen by an English scientist Robert Hooke in the book he published in 1665, after he examined microscopically, cork tissue (a plant material) and saw that they contain neatly arranged little chambers. He compared this chambers to the room monk's lived in and he called them cells. In 1835, a french microscopic zoologist Felix Dujardin, examined a thin slice of animal tissue under much improved microscope and discovered that the cells have content (jelly like material). He named the cntent sarcode. In the same year, Czech experimental physiologist,  Johannes Evangelista Purkinje observed the presence of small granules while looking at the plant tissue through a microscope. Later in 1839, Purkinje named the content, protoplasm, Hugo Von Mohl a German botanist also in 1846 named it protoplasm. In 1838, Mathias Jakob  Schleiden, a germ...

This is the quantity of heat that must be removed to reduce the temperature of the product from its initial temperature to the temerature consistent with good frozen food storage. The heat load is made up of three parts. Heat removed to cool the food from its initial temperature to its freezing point Heat that is removed to cause a state of change at freezing point Heat that is removed to lower the temperature of the frozen product to the specified storage temperatures.  Harvested foods carry field heat expecially in warm climate or hot climate. This heat is called the heat load of that food which needs to be removed in order to achieve low temperature storage of that food. For example carrots harvested at 37oC having that temperature needs to be stored at a temperature of 10oC, droping the temperature from 37 to 10 involves loss of heat, that heat is called the heat loadof carrot. This phenomenon is handy when designing low temperature storage system for harvested...

The drying curve varies according to the type of food and the kind of drier that is used, and also the way the food material also responds to temperature, humidity, air velocity and direction of air and thickness of food. Oil-in-water emulsion dries only quickly than water -in-oil emulsion.  Case hardening is common with foods that contain dissolved sugars and other solutes in high temperature. As water leaves cells of the food, solutes are retained by cell membranes and air spaces in surface layers can act by capillary action whereby water caries solutes to the surface during drying and leaves them there.  In some fruits, this can cause sticky sugary exudates on the surface, which shrinks and clogs pores leading to case hardening. Excerpts from the book, Basic principles of food  processing and preservation: Easy notes by Ukponmwan, Ifueko. Get it from the online store www.morebooks.de  https://www.morebooks.de/gb/search?utf8=%E2%9C%93&q=Ukponmwan+if...

Foods do not loose water at a constant rate down to complete dryness. At  starting of drying, the rate is constant and then it changes. Zero water is never reached under normal drying conditions. During the process of drying, food will loose moisture from its surface and then gradually a thick dried layer develops (an insulative barrier to heat) confining moisture to centre. From the centre, a moisture gradient will develop. During drying, moìsture in the centre has a longer path to travel than moisture near the surface. The drying curve varies according to the type of food and the kind of drier that is used, and also the way the food material also responds to temperature, humidity, air velocity and direction of air and thickness of food. Oil-in-water emulsion dries only quickly than water -in-oil emulsion. Case hardening is common with foods that contain dissolved sugars and other solutes in high temperature. As water leaves cells of the food, solutes are retained by cell mem...

Foods do not loose water at a constant rate down to complete dryness. At  starting of drying, the rate is constant and then it changes. Zero water is never reached under normal drying conditions. During the process of drying, food will loose moisture from its surface and then gradually a thick dried layer develops (an insulative barrier to heat) confining moisture to centre. From the centre, a moisture gradient will develop. During drying, moìsture in the centre has a longer path to travel than moisture near the surface. The drying curve varies according to the type of food and the kind of drier that is used, and also the way the food material also responds to temperature, humidity, air velocity and direction of air and thickness of food. Oil-in-water emulsion dries only quickly than water -in-oil emulsion. Case hardening is common with foods that contain dissolved sugars and other solutes in high temperature. As water leaves cells of the food, solutes are retained by cell mem...