hay, mam abaygar!!! Pinulawan ni namun!!! have mercy

Title: Active yeast effect on starch, sugar and gelatin
Problem: to determine the effect of yeast in compound such as sugar, starch and gelatin. Which of this 3 reacts to the yeast and why?
Question:
1. Is there significant difference in the 3 settings when put by the same amount of yeast?
2..Does the yeast react on the following?
a. starch b. sugar c. gelatin
3.why the yeast react on the following and why not?
a. starch b. sugar c. gelatin
4.what cause the expansion of the balloons on the different setting?



Hypothesis: there is significant difference between the three settings. The balloons on the settings with sugar and starch will expand because the yeast react on these mixture through producing carbon dioxide. While the baloon in setting w/ gelatin will retain its original size since yeasts don't react in gelatin.


Experimental design:
Firsty, we create 3 set ups, one of which is for mixture of starch, another is for sugar and lastly for gelatin. We use the same size of test tube for their containers. Next, put the same amount or quantity of water the containers and pour the same amount of manipulating variables, starch on one test tube, sugar on another and gelatin on the last one. And to test the effect of yeast on the diffirent mixture we put the same amount of yeast on each variable.

Secondly, now the set ups are ready we cover the testubes with the same kind of baloons and leave it to the heat of the sun.

Research Report
Introduction
 Fermentation has been around for a very long time. People have used it for making bread, beer, wine and other products. There have been scientists and chemists who have discovered new things about fermentation. There are many types of fermentation including fermentation of fruit juices, malted grain and other sugars. 
Fermentation
Fermentation is a chemical process that breaks down organic matter. Microbes like bacteria carry out this process. Mold and yeast act upon molasses and mineral salts to create penicillin. Yeast breaks down sugar taken from malted grain and turns it into ethyl alcohol and carbon dioxide gas to make beer. French Scientist Louis Pasteur discovered that microbes ferment beer and wine. Sugar from grape juice breaks down the same way to make wine. Fermentation is also used to make bread, cheese and yogurt. Sometimes fermentation can be unhealthy; for example milk that has been fermented turns sour. There are 1900 other types of fermentation found. Fermentation is also used to make certain drugs, vitamins and some chemicals.
 In 1810 French chemist Joseph Louis GayLussac showed that alcoholic fermentation is expressed by this equation: 
C6H12O6=2CO2 + 2C2H5OH. In 1837 it was independently suggested by German physiologist Theodore Schwann, Botanist Friedrich Kutzing and French physicist Charles Cagniard de la tour that alcoholic fermentation requires yeast cells and it is a physiological function of these organisms. 
Fungi
Fungi are organisms that lack chlorophyll, the green matter that plants use to make their food. Fungi cannot make their own food, instead they absorb it from around them. According to mycologists there are over 100,000 species of fungi. Yeasts and other one-celled fungi are too small to be seen without a microscope. Most types can be seen with the unaided eye. Some of the most common fungi are mildews, molds, mushrooms and plant rusts. Fungi break down complex animal and plant materials into simple compounds. This process of decomposition enriches the soil and makes essential substances available to pants in a form they can use. Through decomposition, fungi also return carbon dioxide to the atmosphere, where green plants reuse it to make food.
Yeast
Yeast is a single celled organism. Yeast is a fungus that exists almost everywhere in nature, including the air. Bakers use yeast to make bread rise. Yeast is used for making beer, wine, and other alcoholic beverages. It consists of masses of microscopic organisms. There are 600 species of yeast, but only a few are used commercially. Yeast grows fast, and it grows best in sugar. Yeast cells reproduce by fission and budding. Bud swelling forms on a yeast cell wall, and then it breaks off to form a new single cell. 
 In the early times yeast was used for bread, beer, wine and other products. In the 1600’s Dutch Scientist Anton Van Leeuwenhoek discovered yeast cells. In 1860 French Scientist Louis Pasteur confirmed that live yeast organisms cause fermentation of beer and wine.
How Yeast Is Used
Since yeast fungi lack chlorophyll, yeast rely on other plants to supply their food. They eat sugar from sources like fruit, grain, nectar and molasses. Yeast cells produce a chemical called enzymes and ferments that break down their food. Some yeast break down sugar into alcohol and carbon dioxide gas, this process is called fermentation. Bakers yeast is used as a leavening, a substance that makes bread rise. Sugar is needed for fermentation. Bakers may add sugar to the dough to hasten fermentation. Yeast breaks down sugar into alcohol and carbon dioxide gas. A substance in the dough called gluten traps the bubbles from the gas. As the gas bubbles expand, the gluten stretches causing the bread to rise. The alcohol produced by fermentation evaporates when the bread is baking. When being baked, the bread yeast is destroyed. 
Yeast used in wine acts on the sugar in grapes and other fruits to produce alcohol and carbon dioxide gas through fermentation. Most wines allow the gas to escape into the air.  In some champagnes and sparkly wines the gas remains to provide the drink’s natural bubbles. 
Brewers yeast cannot act directly on the grain used for beer, so brewers convert the starch in the grain into sugar by means of a process called malting. Yeast is then added to convert the sugar into alcohol. The gas formed during fermentation is pumped off the beer and then added again to carbonate it. 
Yeast is also used for the production of a dietary supplement called single cell protein. Yeast produces large amounts of particular vitamins and is used in the commercial production of vitamins. Yeast used in brewing can absorb and store vitamins from their food. People eat these yeasts as vitamin supplements. Certain yeast fungus can produce large amounts of useful substances such as fat, glycerol, industrial alcohol and various enzymes. The yeast is used in the commercial production of these substances.
How Yeast Is Made
Before the commercial production of yeast in the 1890’s, yeast fungi from the air leavened the bread that people baked. Homemakers prepared dough and left it uncovered and yeasts landed on it and began the fermentation process. Later excess yeast from the beer and winemaking industries was used in breadmaking. This yeast is called barm. When bakers yeast first became an industry, manufacturers grew yeast fungi on malted grain. Today bakers yeast is produced on molasses, which consists mostly of sugar. Bakers yeast is manufactured in two forms, dried grains and moist cakes. Cakes of yeast are made up of live, active cells. Yeast cells in dried grains are live but not active. Dried yeast must be mixed with warm water before yeast fungi can grow. Yeast cakes must be refrigerated, but they spoil after about six weeks. Dried yeast doesn’t need to be refrigerated but it will last longer.
 Fruit
Fruit is the part of a flowering plant that contains the plant's seeds. In this sense, fruits include acorns, cucumbers, tomatoes and wheat grains. Horticulturists define fruit as an edible, seed-bearing structure that (1) consists of fleshy tissue and (2) is produced by a perennial. Therefore horticulturists would classify cucumbers, tomatoes and rhubarb as vegetables. Yet a botanist would classify them as fruits. 
The word "fruit" refers to juicy, sweet or tart kinds of food that people enjoy as snacks or desserts. The word also comes from the Latin word "frui", meaning to enjoy. Popular fruits are apples, bananas, grapes, oranges, pears and strawberries. Many fruits are nutritious and appetizing. For example: oranges and strawberries contain large amounts of vitamin C. Most fruits have high sugar content, so they provide quick energy. Fruits cannot supply a well balanced diet because they do not supply enough protein. 
Types of Fruit
Temperate fruits must have annually cold seasons to grow properly. They must be raised chiefly in temperate zones, regions between tropic and polar areas. Most temperate fruits grow in Europe and North America, but some grow in Asia and Australia, which have major producing areas. Principal temperate fruits include apples, apricots, cherries, peaches, pears and plums.
Subtropical fruits can grow in warm or mild temperatures, but can only survive a light occasional frost. Most widely grown subtropical fruits are the citrus group, which include grapefruit, lemons, limes and oranges. Other subtropical fruits are dates, figs, olives and avocados. 
Tropical fruits are raised mainly in the tropic areas and can’t survive even a light frost. Bananas and pineapples are the best known tropical fruits grown throughout the tropics and much of each crop is exported. Other tropical fruits are acerolas, cherimoyas, litchis, mangoes, mangosteens and papayas.
Sugar
Green plants produce sugar, but most table sugar comes from sugar cane or beets. Other sources of sugar are cornstarch, milk, maple syrup and honey. Sugar belongs to the class of foods called carbohydrates. Carbohydrates provide energy for plants and animals. There are two kinds of sugar monosaccharides and disaccharides. Monosaccharides are the simplest carbohydrates, include glucose and fructose. Glucose is the most important carbohydrate in the blood. Fructose is found in fruits and vegetables. Common disaccharides include lactose and maltose. Lactose is found in milk and is used in the production of some medications. Maltose is formed from starch and it is used in the production of bread and baby food.
Summary
 There are many different things needed for fermentation including, yeast, fruit juice or malted grain, and sugar. Fermentation produces many products like bread, cheese, yogurt, wine and beer. One unhealthy product of fermentation is fermented milk.


HYPOTHESIS
My hypothesis is that the fruit juice with a higher percentage of sugar will produce more fermentation. 
I base my hypothesis on the World Book Encyclopedia, which states, 
"Yeast breaks down sugar obtained from fruit juice into ethyl alcohol and carbon dioxide gas for use in wine."
Top of page



EXPERIMENT DESIGN
The constants in this study were:
The temperature.
The amount of juice (250ml).
The amount of yeast (1g)
Size and shape of container
Time allowed to ferment.
Method of measurement.

The manipulated variable was the type of fruit juice.
The responding variable was the amount of fermentation as shown by the reduction of sugar.
To measure the responding variable I used a brix meter to find the percentage of sugar before and after fermentation for each sample to calculate the difference.

Most organisms require oxygen and sugar to aide in reproduction, but what effect does sugar have on the rate of reproduction of yeast? 
From research, it is known that yeast can reproduce under aerobic and anaerobic conditions.  If we limit the oxygen that is available
for yeast reproduction and increase the amount of sugar the yeast can react with, we expect the yeast will use the sugar for energy and reproduction. 
With this information, we sought to find a correlation between dissolved oxygen rates and varying sugar concentrations added to an aqueous solution that contained living yeast.
  Because yeast typically use oxygen to reproduce, we hypothesized and predicted that if yeast had more sugar available to react with, the yeast
would use more oxygen when reacting with the increased sugar concentrations, and thus, we would see less dissolved oxygen after the 20-minute trial.  

Baking
Main article: Baker's yeast
Yeast, most commonly Saccharomyces cerevisiae, is used in baking as a leavening agent, where it converts the fermentable sugars present in the dough into carbon dioxide. This causes the dough to expand or rise as the carbon dioxide forms pockets or bubbles. When the dough is baked it "sets" and the pockets remain, giving the baked product a soft and spongy texture. The use of potatoes, water from potato boiling, eggs, or sugar in a bread dough accelerates the growth of yeasts. Salt and fats such as butter slow down yeast growth. The majority of the yeast used in baking is of the same species common in alcoholic fermentation. Additionally, Saccharomyces exiguus (also known as S. minor) is a wild yeast found on plants, fruits, and grains that is occasionally used for baking. Sugar and vinegar are the best conditions for yeast to ferment. In bread making the yeast respires aerobically at first producing carbon dioxide and water. When the oxygen is used up anaerobic respiration is used producing ethanol as a waste product however this is evaporated off during the baking process.


A block of fresh yeast.
It is not known when yeast was first used to bake bread. The first records that show this use came from Ancient Egypt.[28] Researchers speculate that a mixture of flour meal and water was left longer than usual on a warm day and the yeasts that occur in natural contaminants of the flour caused it to ferment before baking. The resulting bread would have been lighter and more tasty than the normal flat, hard cake.


Active dried yeast, a granulated form in which yeast is commercially sold.
Today there are several retailers of baker's yeast; one of the best-known in North America is Fleischmann’s Yeast, which was developed in 1868. During World War II Fleischmann's developed a granulated active dry yeast, which did not require refrigeration and had a longer shelf life than fresh yeast. The company created yeast that would rise twice as fast, cutting down on baking time. Baker's yeast is also sold as a fresh yeast compressed into a square "cake". This form perishes quickly, and must be used soon after production in order to maintain viability. A weak solution of water and sugar can be used to determine if yeast is expired. When dissolved in the solution, active yeast will foam and bubble as it ferments the sugar into ethanol and carbon dioxide. Some recipes refer to this as proofing the yeast as it gives proof of the viability of the yeast before the other ingredients are added. When using a sourdough starter, flour and water are added instead of sugar and this is referred to as proofing the sponge.
When yeast is used for making bread, it is mixed with flour, salt, and warm water (or milk). The dough is kneaded until it is smooth, and then left to rise, sometimes until it has doubled in size. Some bread doughs are knocked back after one rising and left to rise again. A longer rising time gives a better flavour, but the yeast can fail to raise the bread in the final stages if it is left for too long initially. The dough is then shaped into loaves, left to rise until it is the correct size, and then baked. Dried yeast is usually specified for use in a bread machine, however a (wet) sourdough starter can also work.
he word "yeast" comes from the Sanskrit 'yas' meaning "to seethe or boil".  Yeast is a living organism and is in the air around us.  It is a  member of the fungus family and is a single-celled fungi of which there are about 160  different species.  Baker's yeast as well as brewer's yeast belong to the Saccharomyces cerevisiae species.  Louis Pasteur in the 1850's is credited with first discovering and understanding the fermentation process which led to the development and cultivation of the yeast we use today. 



Baker's yeast, like baking powder and baking soda, is used to leavened baked goods (breads, Danish pastries, brioche, croissants).  The difference between these two leaveners is that baking powder/soda react chemically to produce the carbon dioxide that makes the baked goods rise.  Yeast, on the other hand, is a living organism and the carbon dioxide it produces is the result of the yeast feeding on the dough. 
The two forms of baker's yeast are; compressed cakes (also called fresh yeast) and dehydrated granules (dry yeast). 
Fresh yeast is ivory colored with a yellowish hue and is soft and moist and should easily crumble.  Make sure it is fresh smelling and there are no dark or dried places on the yeast.   It is mainly used by professionals as it is highly perishable and must be used within a short time of opening.   It is sold is .06 ounce foil packages and must be refrigerated.  For longer term storage it can be frozen.   Compressed yeast contains about 70% moisture.   It needs to be proofed before using and should have a pleasant yeasty smell and be foamy. 
Dry yeast is fresh compressed yeast that has been pressed and dried until the moisture content is only about 8% which makes the yeast dormant.  The granules only become active again when mixed with a warm liquid.  The advantage of dry yeast is it has a much longer shelf life than fresh yeast and does not need to be refrigerated.  This makes it a  favorite among home bakers.   The tiny, dehydrated, bead-shaped, sand colored granules are most often sold in convenient small foil-lined packages weighing 1/4 ounce (7 grams) that have been packaged under pressure.   Always check the expiration date on the package before buying.   It is also sold in 4 ounce jars but once opened, the yeast needs to be stored in the refrigerator away from moisture, heat, and light because once yeast is exposed to air it deteriorates rapidly.    
There are two types of dry yeast:  regular active dry and rapid-rise.  The two types of dry yeast can be used interchangeably.  The advantage of the rapid-rise is the rising time is half that of the active dry and it only needs one rising.  However, you do sacrifice flavor and texture in order to save time as the yeast does not have time to develop its own flavor. 
You may have noticed that in some recipes it calls for dissolving the yeast first in a warm liquid and then adding this active yeast mixture to the flour.  Other recipes, however, call for the yeast first being added to the flour and then the warm liquid is added.  The dissolving of the yeast first in a warm liquid is done to make sure the yeast is still fresh and active.  This step really doesn't need to be done though because of how reliable the dry yeast is today.  Also, the dry yeast has such a small granule size that it dissolves easily into the dough without having to be reconstituted separately.  Some bakers, however, still feel that it is a good idea to test the yeast to make sure it is still active before adding it to the flour.
Yeast must have three things in order to grow:  Moisture, Food, and Warmth.



To activate yeast the first step is called proofing and is a way to test the yeast to make sure it is alive and still active.  This is accomplished by mixing the yeast in a warm liquid.  In order for yeast to become very active it needs food.  It's favorite food is sugar, simple sugars to be precise (glucose and fructose).  Some recipes call for adding granulated white sugar which the yeast will break down into its simpler form.  But in some bread recipes where sugar is not used, flour can be added to the warm liquid and the yeast will break down some of the starch in the flour to a simple sugar.  
Once the yeast, liquid, and flour are mixed together and distributed, the next step is to knead the dough.  This step is done to aerate the dough and develops the gluten (elasticity) in the flour.  As you knead (press-fold-turn action) pockets of air are developed in the dough.  The more you knead the smaller and more numerous the pockets of air become.  How the dough is kneaded will determine the final texture of the bread.  Dough with larger air pockets will produce a bread with a coarser texture.  Commercially made breads or homemade ones that are kneaded by machine tend to have a finer texture than breads kneaded by hand.  You'll know when the dough has been kneaded enough as it takes on a smooth and satiny appearance.
The next step is the fermentation or rising of the dough.  This is where the dough is placed in a greased bowl and covered with plastic wrap or a clean dish towel to avoid moisture loss and a dry, crusty surface from forming. The dough is then left in a warm, draft-free environment to rise until about double in size.  The rising starts slowly as the yeast begins to feed on the sugar.  Carbon dioxide and alcohol are produced and the carbon dioxide stretches and expands the existing air pockets in the dough and the dough starts to rise.  This is also where the bread's flavor is developed.  A dough that doesn't rise sufficiently will be very compact.
Once the dough has doubled in size this signals the next step i.e. the punching down of the dough.  This 'punching down' is where the dough is deflated, thereby releasing the large air pockets formed during rising and evenly distributes the temperature and yeast throughout the mass of dough.  Depending on what you are making, at this point there may be a second rising.  Otherwise, the dough is shaped and placed in a pan and allowed to rise for a shorter period of time. 
The final step is the baking of the bread.  The temperature of the oven can vary depending on the baked good.  A sweet dough is normally baked at about 350 - 375 F (175 - 190 C).  Other dough can be baked at a higher temperature 400 - 425 F (205 - 220 C).  During the first part of baking, before the yeast is killed, the dough will rise as you get a last bit of carbon dioxide being released and expanding the air pockets.  Once the yeast is killed and the interior of the baked good heats up enough, the dough will set.  The last part of the baking is where you get surface browning and this adds flavor and texture to the baked good.  Often times the surface of the baked good is brushed with an egg wash (can also place a pan of hot water in the oven or spray the baked good with water periodically during baking) before baking so the crust will be nicely browned and glossy.
How long the baked good stays fresh is dependent on the sugar content.  French breads that do not contain sugar have a very short shelf life.  On the other hand, a sweet dough that contains sugar can stay fresh for several days.

Gwapzzz
---HYPOTHESIS
My hypothesis is that the fruit juice with a higher percentage of sugar will produce more fermentation. 
I base my hypothesis on the World Book Encyclopedia, which states, 
"Yeast breaks down sugar obtained from fruit juice into ethyl alcohol and carbon dioxide gas for use in wine."
Top of page



EXPERIMENT DESIGN
The constants in this study were:
The temperature.
The amount of juice (250ml).
The amount of yeast (1g)
Size and shape of container
Time allowed to ferment.
Method of measurement.

The manipulated variable was the type of fruit juice.
The responding variable was the amount of fermentation as shown by the reduction of sugar.
To measure the responding variable I used a brix meter to find the percentage of sugar before and after fermentation for each sample to calculate the difference.


Research Report
Introduction
 Fermentation has been around for a very long time. People have used it for making bread, beer, wine and other products. There have been scientists and chemists who have discovered new things about fermentation. There are many types of fermentation including fermentation of fruit juices, malted grain and other sugars. 
Fermentation
Fermentation is a chemical process that breaks down organic matter. Microbes like bacteria carry out this process. Mold and yeast act upon molasses and mineral salts to create penicillin. Yeast breaks down sugar taken from malted grain and turns it into ethyl alcohol and carbon dioxide gas to make beer. French Scientist Louis Pasteur discovered that microbes ferment beer and wine. Sugar from grape juice breaks down the same way to make wine. Fermentation is also used to make bread, cheese and yogurt. Sometimes fermentation can be unhealthy; for example milk that has been fermented turns sour. There are 1900 other types of fermentation found. Fermentation is also used to make certain drugs, vitamins and some chemicals.
 In 1810 French chemist Joseph Louis GayLussac showed that alcoholic fermentation is expressed by this equation: 
C6H12O6=2CO2 + 2C2H5OH. In 1837 it was independently suggested by German physiologist Theodore Schwann, Botanist Friedrich Kutzing and French physicist Charles Cagniard de la tour that alcoholic fermentation requires yeast cells and it is a physiological function of these organisms. 
Fungi
Fungi are organisms that lack chlorophyll, the green matter that plants use to make their food. Fungi cannot make their own food, instead they absorb it from around them. According to mycologists there are over 100,000 species of fungi. Yeasts and other one-celled fungi are too small to be seen without a microscope. Most types can be seen with the unaided eye. Some of the most common fungi are mildews, molds, mushrooms and plant rusts. Fungi break down complex animal and plant materials into simple compounds. This process of decomposition enriches the soil and makes essential substances available to pants in a form they can use. Through decomposition, fungi also return carbon dioxide to the atmosphere, where green plants reuse it to make food.
Yeast
Yeast is a single celled organism. Yeast is a fungus that exists almost everywhere in nature, including the air. Bakers use yeast to make bread rise. Yeast is used for making beer, wine, and other alcoholic beverages. It consists of masses of microscopic organisms. There are 600 species of yeast, but only a few are used commercially. Yeast grows fast, and it grows best in sugar. Yeast cells reproduce by fission and budding. Bud swelling forms on a yeast cell wall, and then it breaks off to form a new single cell. 
 In the early times yeast was used for bread, beer, wine and other products. In the 1600’s Dutch Scientist Anton Van Leeuwenhoek discovered yeast cells. In 1860 French Scientist Louis Pasteur confirmed that live yeast organisms cause fermentation of beer and wine.
How Yeast Is Used
Since yeast fungi lack chlorophyll, yeast rely on other plants to supply their food. They eat sugar from sources like fruit, grain, nectar and molasses. Yeast cells produce a chemical called enzymes and ferments that break down their food. Some yeast break down sugar into alcohol and carbon dioxide gas, this process is called fermentation. Bakers yeast is used as a leavening, a substance that makes bread rise. Sugar is needed for fermentation. Bakers may add sugar to the dough to hasten fermentation. Yeast breaks down sugar into alcohol and carbon dioxide gas. A substance in the dough called gluten traps the bubbles from the gas. As the gas bubbles expand, the gluten stretches causing the bread to rise. The alcohol produced by fermentation evaporates when the bread is baking. When being baked, the bread yeast is destroyed. 
Yeast used in wine acts on the sugar in grapes and other fruits to produce alcohol and carbon dioxide gas through fermentation. Most wines allow the gas to escape into the air.  In some champagnes and sparkly wines the gas remains to provide the drink’s natural bubbles. 
Brewers yeast cannot act directly on the grain used for beer, so brewers convert the starch in the grain into sugar by means of a process called malting. Yeast is then added to convert the sugar into alcohol. The gas formed during fermentation is pumped off the beer and then added again to carbonate it. 
Yeast is also used for the production of a dietary supplement called single cell protein. Yeast produces large amounts of particular vitamins and is used in the commercial production of vitamins. Yeast used in brewing can absorb and store vitamins from their food. People eat these yeasts as vitamin supplements. Certain yeast fungus can produce large amounts of useful substances such as fat, glycerol, industrial alcohol and various enzymes. The yeast is used in the commercial production of these substances.
How Yeast Is Made
Before the commercial production of yeast in the 1890’s, yeast fungi from the air leavened the bread that people baked. Homemakers prepared dough and left it uncovered and yeasts landed on it and began the fermentation process. Later excess yeast from the beer and winemaking industries was used in breadmaking. This yeast is called barm. When bakers yeast first became an industry, manufacturers grew yeast fungi on malted grain. Today bakers yeast is produced on molasses, which consists mostly of sugar. Bakers yeast is manufactured in two forms, dried grains and moist cakes. Cakes of yeast are made up of live, active cells. Yeast cells in dried grains are live but not active. Dried yeast must be mixed with warm water before yeast fungi can grow. Yeast cakes must be refrigerated, but they spoil after about six weeks. Dried yeast doesn’t need to be refrigerated but it will last longer.
 Fruit
Fruit is the part of a flowering plant that contains the plant's seeds. In this sense, fruits include acorns, cucumbers, tomatoes and wheat grains. Horticulturists define fruit as an edible, seed-bearing structure that (1) consists of fleshy tissue and (2) is produced by a perennial. Therefore horticulturists would classify cucumbers, tomatoes and rhubarb as vegetables. Yet a botanist would classify them as fruits. 
The word "fruit" refers to juicy, sweet or tart kinds of food that people enjoy as snacks or desserts. The word also comes from the Latin word "frui", meaning to enjoy. Popular fruits are apples, bananas, grapes, oranges, pears and strawberries. Many fruits are nutritious and appetizing. For example: oranges and strawberries contain large amounts of vitamin C. Most fruits have high sugar content, so they provide quick energy. Fruits cannot supply a well balanced diet because they do not supply enough protein. 
Types of Fruit
Temperate fruits must have annually cold seasons to grow properly. They must be raised chiefly in temperate zones, regions between tropic and polar areas. Most temperate fruits grow in Europe and North America, but some grow in Asia and Australia, which have major producing areas. Principal temperate fruits include apples, apricots, cherries, peaches, pears and plums.
Subtropical fruits can grow in warm or mild temperatures, but can only survive a light occasional frost. Most widely grown subtropical fruits are the citrus group, which include grapefruit, lemons, limes and oranges. Other subtropical fruits are dates, figs, olives and avocados. 
Tropical fruits are raised mainly in the tropic areas and can’t survive even a light frost. Bananas and pineapples are the best known tropical fruits grown throughout the tropics and much of each crop is exported. Other tropical fruits are acerolas, cherimoyas, litchis, mangoes, mangosteens and papayas.
Sugar
Green plants produce sugar, but most table sugar comes from sugar cane or beets. Other sources of sugar are cornstarch, milk, maple syrup and honey. Sugar belongs to the class of foods called carbohydrates. Carbohydrates provide energy for plants and animals. There are two kinds of sugar monosaccharides and disaccharides. Monosaccharides are the simplest carbohydrates, include glucose and fructose. Glucose is the most important carbohydrate in the blood. Fructose is found in fruits and vegetables. Common disaccharides include lactose and maltose. Lactose is found in milk and is used in the production of some medications. Maltose is formed from starch and it is used in the production of bread and baby food.
Summary
 There are many different things needed for fermentation including, yeast, fruit juice or malted grain, and sugar. Fermentation produces many products like bread, cheese, yogurt, wine and beer. One unhealthy product of fermentation is fermented milk.
----langka
Yeast in this form is alive and potentially ready to begin feeding and producing all of those useful byproducts we discussed last month. It only needs to be warmed to a temperature of 50 F or more to get this yeast activated and feeding. This is the reason why the yeast must be kept refrigerated at all times.

This is also the type of yeast for which the old admonishment-never allow the yeast to come into direct contact with either salt or sugar-was developed.

What happens here is if the yeast is allowed to contact salt or sugar, either of the two substances will draw the moisture out of the yeast, thus damaging it to a point where it may lose its fermentative properties. In some instances, the yeast may actually be killed.

----waay na
Preface
A baker learns early in the baking process that it is difficult to make fine bread unless he or she gains a fair degree of insight into many of the chemical, physical, biological and mechanical aspects of the baking craft.  It is fitting that one of the seemingly most simple of organisms - a yeast cell - offers challenges that defy that assumed simplicity.  Yeast is a very complex organism, and its effects on baking are complex.  In this treatise we have tried to review as much of the literature available to us, and to distill it into a reasonably brief review of that literature. Since The Artisan has no research facilities capable of doing independent research aimed at better understanding what yeast does and why it does it,  we have relied on many sources.  However, that does not mean that any errors or misconstrued conclusions are the fault of those sources.  Errors of either commission or omission are ours, and ours alone.  We hope that visitors will inform us of any errors that we have made, and allow us the opportunity to correct said errors as appropriate.
Source materials for this Treatise have come from those authors and the works cited in the Bibliography found at the end of this document.
Introduction

The baking process represents a highly complex set of physical, chemical, biochemical and biological activities. The microscopic yeast cell is responsible for the most important of these - Fermentation. Thus, yeast is the primary biological agent in dough formation, and discussions of yeast and its functions in the baking process are invariably intertwined with those pertaining to fermentation, and visa versa.

What are yeasts? Yeasts belong to the phylum Thalophytes. Members of this phylum form the most basic division of organisms in the plant kingdom, and are an undifferentiated group. Yeasts belong to this phylum along with other funghi, algae, and bacteria. Since funghi lack chlorophyll, they are dependent for food upon other organism's production of organic food matter. (Pyler) Thus, yeast must be fed to accomplish the task of leavening the dough. Yeast used in bread baking belongs to the genus Saccharomycetes and the species cerevisiae. More about this below.

Biology of Yeast Cells - Simplified

Yeast are a tiny form of fungi or plant-like microorganism (visible only under a microscope) that exist in or on all living matter i.e. water, soil, plants, air, etc. A common example of a yeast is the bloom we can observe on grapes. As a living organism yeast needs sugars, water and warmth to stay alive. In addition, albumen or nitrogenous material are also necessary for yeast to thrive.

There are hundreds of different species of yeast identified in nature, but the genus and species most commonly used for baking is Saccharomyces cereviae. The scientific name Saccharomyces cerevisiae, means 'a mold which ferments the sugar in cereal (saccharo-mucus cerevisiae) to produce alcohol and carbon dioxide'. Yeast needs energy to survive, and has a number of ways to attain that energy.   Fermentation and respiration are two ways   The ultimate reaction of importance in this process is the an-aerobic conversion of simple sugars to ethyl alcohol and carbon dioxide during alcoholic fermentation as shown below. Although not shown in the fermentation reaction,  numerous other end products are formed during the course of fermentation
Simple Sugar      →      Ethyl Alcohol + Carbon Dioxide
C6 H12 O6     →     2C H3 CH2 OH + 2CO2
The basic respiration reaction is shown below.   The differences  between an-aerobic fermentation and aerobic respiration can be seen in the end products. Under aerobic conditions, yeasts convert sugars to carbon dioxide,  water and cellular mass. (Giorilli & Lauri)
Simple Sugar + Oxygen       →    Carbon Dioxide + Water
C6 H12 O6 +  6O2   →      6CO2 + 6H2O
Examining a yeast cell under a microscope will give a greater understanding of the composition and nature of yeast. The method for viewing a sample of yeast under a microscope is to disperse a small amount of yeast in water, causing the water to be slightly clouded, and then drop a spot of the liquid onto a glass slide. The drop is then covered and viewed with a 650 x magnification. The individual cells will take the general form illustrated in Figure 1.

When viewed under the microscope, one sees round or oval cells about 1/100 of a millimeter in diameter, which weigh about 8 to 10 billion to the gram. (Calvel et al) If individual yeast cells were placed side by side it would take approximately 1200 cells to measure 1cm in length. Inside each cell are the following:
A liquid solution of protoplasm, protein, fat and mineral matter.
One or more dark patches called vacuoles.
A darker spot which is the nucleus. This is where the cell's genetic information is stored as  DNA   which controls all the operations of the cell.
A yeast cell has 6000 different yeast genes. Like any living thing, yeast is made up of chromosomes; there are 16 different chromosomes in yeast compared with 23 in humans.

The double cell wall may have bud scars (seen in Figure 1 to the right), which are caused by budding, i.e. the cell reproducing itself. There can be up to ten such scars, which cover the cell totally, after which the cell expires.

This happens (generally speaking) as follows:

Compared with other plant organisms, yeast has a much better chance of survival in spite of harsh environmental conditions. It is independent from climate and soil conditions. It is not dependent on any location and can survive for hundreds of years as a spore.

Under favorable living conditions, yeast multiplies through the separation of cells (budding) or yeast multiplication. Under unfavorable living conditions, when water and nutrients are lacking, the yeast forms spores.
Cell Separation (Budding)

The cell core migrates to the cell wall of the yeast cell. It splits up and forms a daughter cell. The daughter cell multiplies in the same way while it is still growing and tied to the mother cell. A colony develops. Later, the daughter cell separates from the mother cell. The multiplication process continues for as long as the conditions for multiplication are present. This is depicted in Figure 2. As can be seen, a parent cell grows a protuberance, this swells as the bud forms, a neck develops between the parent cell and the bud, and they separate. The process starts again and, in ideal conditions, a cell can reproduce itself in 20 minutes so that numbers increase from one to two, then to four, to eight, to 16, and so on. If the numbers are plotted on a graph, the line would take an exponential form.
Figure 2


Sporulation

Spores form once the nutrients of a solution are used up. The yeast becomes dormant and feeds on its reserve material. When the nutrient solution and the yeast cells dry out, the cell core separates and forms spores. The spores are insensitive to heat and cold. The slightest breeze carries them anywhere. Under dry conditions, the spores can live forever. When spores fall into a nutrient solution, they germinate into yeast cells. Each yeast cell can give rise to four spores.

Simple sugars: The main simple sugars, glucose and fructose, represent about 0.5% of the flour. Yeast can directly assimilate them by penetration of the cell membrane. Simple sugars are transformed into alcohol and carbon dioxide by zymase, an enzyme naturally present in yeast cells. Because of this easy absorption, these sugars are the first ones used in the fermentation process. Their consumption takes place during the first 30 minutes or so at the beginning of the fermentation process.

----tuyo na ko
Yeast is a living organism: a one-celled fungus. Various strains of yeast are present virtually everywhere. Yeast feeds on carbohydrates, converting them to carbon dioxide and alcohol in an organic process known as fermentation:

Yeast + Carbohydrates = Alcohol + Carbon Dioxide

When yeast releases carbon dioxide gas during bread making, the gas becomes trapped in the dough's gluten network. The trapped gas leavens the bread, providing the desired rise and texture. The small amount of alcohol produced by fermentation evaporates during baking. As with most living things, yeast is very sensitive to temperature. It prefers temperatures between 90˚F and 110˚F (32˚C-43˚C). At temperatures below 34˚F (2˚C), it becomes dormant; above 138˚F (59˚C), it dies. Salt is used in bread making because it conditions gluten, making it stronger and more elastic. Salt also affects yeast fermentation. Because salt inhibits the growth of yeast, it helps control the dough's rise. Too little salt and not only will the bread taste bland, it will rise too rapidly. Too much salt, however, and the yeast will be destroyed. By learning to control the amount of food for the yeast and the temperatures of fermentation, you can learn to control the texture of your yeast-leavened products. Types of Yeast Baker's yeast is available in two forms: compressed and active dry. (You may also encounter a product called brewer's yeast; it is a nutritional supplement with no leavening ability.)
----matulog na ku..
Gelatin is a protein produced by partial hydrolysis of collagen extracted from the bones, connective tissues, organs, and some intestines of animals such as the domesticated cattle, and horses. The natural molecular bonds between individual collagen strands are broken down into a form that rearranges more easily. Gelatin melts when heated and solidifies when cooled again. Together with water, it forms a semi-solid colloid gel. Gelatin forms a solution of high viscosity in water, which sets to a gel on cooling, and its chemical composition is, in many respects, closely similar to that of its parent collagen. [1] Gelatin solutions show viscoelastic flow and streaming birefringence. If gelatin is put into contact with cold water, some of the material dissolves. The solubility of the gelatin is determined by the method of manufacture. Typically, gelatin can be dispersed in a relatively concentrated acid. Such dispersions are stable for 10-15 days with little or no chemical changes and are suitable for coating purposes or for extrusion into a precipitating bath. Gelatin is also soluble in most polar solvents. Gelatin gels exist over only a small temperature range, the upper limit being the melting point of the gel, which depends on gelatin grade and concentration and the lower limit, the ice point at which ice crystallizes. The mechanical properties are very sensitive to temperature variations, previous thermal history of the gel, and time. The viscosity of the gelatin/water mixture increases with concentration and when kept cool (≈ 4 °C).