Study of Vinegar Fermentation

There are many substances that can be manipulated and cause the rate of reaction in fermentation to either speed up or slow down. Substances that alter the rate of the reaction could be temperature of the water, the yeast concentration, pH, and the glucose concentration. In the experimental group of the experiment the amount of yeast concentration was manipulated. The objective of this experiment was to determine what factors affect the rate of the fermentation. To test this objective we changed the amount of yeast being used. A higher yeast concentration replaced the controlled yeast amount. A prediction made by my group was that higher amount of yeast would speed up the process of fermentation. Our null hypothesis is there will be no

The aim of this experiment was to see how temperature affected the rate of fermentation. To test this a yeast and glucose solution was submerged in water baths with the temperatures of 20oC, 30oC and 40oC. The test was left over night to gain optimum results. The rate of fermentation was measured by the amount of carbon dioxide produced. It was believed that the solution submerged in the 40oC water bath would produce the most carbon dioxide and therefore ferment the fastest. Results showed that the hypothesis was correct as after 25 hours the solution submerged in the 40oC water bath had produced the most carbon dioxide.

4) One package of active dry yeast was added to bottle labeled ‘5mL’ and solution was swirled.

3.0g of salicylic acid was weighed then 3.0mL of acetic anhydride and 6 drops of 85% H3PO4 were added to it. The mixture was warmed over a water bath for 5 minutes while stirring. After warming, 20 drops of distilled water was slowly added. 15mL of water was added then the solution was heated until it became clear. It was allowed to cool and was placed in an ice bath until the solution becomes cloudy. Using pre-weighed filter paper, the mixture was filtered and was allowed to dry in the filter paper.

Abstract: This lab’s purpose was to see how different levels of yeast, distilled water, and sugar interact to affect the level of carbon dioxide evolved in fermentation. In this experiment we had two sections. The first section tested four test tubes with varying levels of yeast, glucose and distilled water for evolved carbon dioxide levels. The tubes were timed for 20 minutes. The amounts of solution in the test tubes are noted in the methods section of this lab report. The second section of the lab used three test tubes and flowed the same procedure except added spices. The levels of ingredients are also in the methods section. The main goal of this experiment was to see the effects of yeast concentration.

The titration worked well and yielded decent results. It was found that 72.10 mg of ascorbic acid is contained within a serving of lemonade.The %w/w of ascorbic acid is .30%. The volumes collected and observations made worked out to give proper and expected values. Rinsing the burette and pipette was important to this as it removed any water or dust inside. This meant that final volumes and calculations were more precise as there were fewer sources of error. The standard deviation obtained from the four trials was 0.22 mL. Much of this error is due to the rapid colour change. This made it difficult to precisely end the titration when the endpoint was reached. Another source of error is found in the assumption that because a colour change happened the proper reaction had occurred. This assumption while very basic and small potentially had a slight impact on final results. Titrations are very simple and therefore are empirical, and based off simple measurements with these simple assumptions accuracy decreases and error

Objective: The objective of this experiment is to use acid-base extraction techniques to separate a mixture of organic compounds based on acidity and/or basicity. After the three compounds are separated we will recover them into their salt forms and then purify them by recrystallization and identify them by their melting points.

We are all aware of the entire buzz circulating around the Internet and certain health circles about all the benefits that are associated with Apple Cider Vinegar. So, what is the big deal about Apple Cider Vinegar? Are the claims true? First, it is important to know a little background about the product. Apple Cider Vinegar or AVC is actually a product that comes from apples. It is produced by crushing the apples and obtaining the juice, which is fermented and turned into alcohol. It does not stop at that point. A second fermentation process takes place to convert the product into vinegar.

PH can affect the way fermentation occurs due to the irregularity of the acidity or alkalinity within the glucose concentration. The aim of this experiment is to determine how pH affects the yeast fermentation rate by performing the experiment numerous times with a different pH in the glucose solution. My hypothesis states that ‘If the pH is lower than the neutral point then the fermentation reaction will occur faster?’ To set this experiment I had to make adjustments to the original practical method in order to fit the new practical, which depended on the question that was chosen.

The temperature of the water that the test tubes sit in is another controlled variable. This is because temperature is known to affect rate of fermentation. This can be controlled by using the same water bath to heat all 6 test tubes.

The original solution once the 1-butanol, hydrobromic acid, and sulfuric acid were added was yellow-orange in color. After distilling the distillate was clear then became partially cloudy. The calculated yield of the product was approximately 5.41%. The calculated yield was low due to a fluctuating temperature during the reaction and possible impurities formed.

3. A few drops of 6 M acetic acid were added until it became basic.

Approximately 8.8ml of sodium hydroxide will be required to neutralize 100ml of acetic acid. (http://schoolworkhelper.net/titration-of-vinegar-lab-answers/)

First, three titration curves and three second derivative curves were created to determine the average pH at the half-equivalence point from the acetic acid titrations. Titration curves were used as visuals to portray buffer capacity. The graphs and a table, Table 1, that showcased the values collected were created and included below. The flat region, the middle part, of Figures 1, 2 and 3, showed the zone at which the addition of a base or acid did not cause changes in pH. Once surpassed, the pH increased rapidly when a small amount of base, NaOH, was added to the buffer solution. Using the figures below and

Food preservatives are described as natural means or man-made chemicals that are used in foods to prevent them from spoiling. A subgroup of preservatives are food additives, which differ from preservatives in the way that additives are not only used to lengthen the life of food, but also to improve taste and appearance. The ultimate goal of preservatives and additives are to improve the quality and lifespan of food by slowing down the decomposition process using chemicals or natural methods, such as salt and dehydration.