Synthesis of Isoamyl Acetate Using the Fischer Esterification MethodEssay Preview: Synthesis of Isoamyl Acetate Using the Fischer Esterification MethodReport this essaySynthesis of Isoamyl Acetate Using the Fischer Esterification MethodMark Jason Santos, Grace Sharmine Sotto, Chrio Sta. Ana, Lorenzo Terania*Department of Biological Sciences, College of ScienceUniversity of Santo Tomas, España, Manila 1008AbstractThe objective of this experiment is to produce isoamyl acetate and to determine the yield and also percent yield to measure the effectiveness of the synthetic procedure. Isoamyl acetate is used to confer banana flavor in food. Isoamyl alcohol and acetic anhydride were used to make isoamyl acetate. Fischer esterification was the method used. Using the formula to compute the percent yield, it was determined to be 81.49%.
Additional information:
A preliminary study on the yield and yield intensity of isoamyl acetate was carried out, and the analysis did not include any changes of taste or aroma.
A similar experiment was carried out on a different substrate using different methods and with different experimental conditions, but this one was used in the same sample and was compared to the experiment conducted on Isoamyl acetate (Isoamyl acetate).
The results are shown on Table 1 of this paper.
Using the Isoamyl acetate mixture (Isoamyl acetate at 90% HCl), the yield of isoamyl acetate was determined. According to the method described, the yield of the mixture with isoamyl acetate was about 7% with the alcohol mixture and 2.78% with acetic anhydride. This means that while isoamyl acetate has a strong additive profile, it was not produced when the mixture was not used, as expected. If the ratio of isoamyl acetate with acetic anhydride was 1.0 or less, the yield of isoamyl acetate was 0.8-1%, whereas if the ratio was 3.0 or more, it was estimated that the yield of isoamyl acetate to acetic anhydride was 8.75-9.5%.
Previous studies of this assay have demonstrated the high yield potential of Isoamyl acetate from Isoamyl acetate, including a small sample in this study with a high yield with 5% acetic anhydride at 90% HCl and the average yield of isoamyl acetate at 3.3%. This would indicate that the yield of isoamyl acetate of 80-90% HCl was similar to that of acetic anhydride.
In the present study, isoamyl acetate (0.8- 1.0%) and acetic anhydride (5-11%) were evaluated after oral ingestion of banana starch. In the present study, acetic anhydride was investigated at a level of 70% HCl at 25% relative to the amount of extract from the extract. On the basis of the results obtained with this method, it follows that the yield of isoamyl acetate was about 7% with the alcohol mixture and 3.1% for acetic anhydride. This yield of isoamyl acetate was not comparable to the yield of acetic anhydride. Although the yield of isoamyl acetate had been obtained at all levels of potency in this research group, in the absence of any adverse results, it follows that the yield did not differ with potency and it seems reasonable to assume that the highest levels of potency were produced by the highest potency preparation. Furthermore, this yield is comparable to that of acetic anhydride of 0.8-1% with 0.25 AC at 100:40:1, which are typical for low potency starch.
The extract preparation is also capable of enhancing both α-amylase and beta-amylase. It is interesting that α-amylase is present in the extract produced in the present study and does not react with acetic anhydride. The α-amylase assay is a positive and the reaction rate is 1,000%, while the reaction rate for acetylate and acetic anhydride is 1.2 s in each case. A higher proportion of α-amylase activity is expected due to the high sensitivity of α-amylase to specific amylases of the α-amylase family such as α-lactosome 2, lpRNA (8, 13), or m-glycolic acid (9, 30). These molecules are readily recognized and most important proteins in the cell are expressed in the intestinal mucosa. They are usually also involved in production of amyloid beta-carotene and a number of its precursors such as choline and prostaglandin-6. Although there is still a low tolerance for alpha-amylase for these foods, they are less likely to be consumed and are often eaten in foods prepared by inexperienced chefs.
This study is not an exact study to compare isoamyl acetate to other starch extract methods and it is inconceivable that it would produce any significant differences between these extracts before the end of the study due to different results of this study. I want to draw a few conclusions. First, the present study appears to show two different results of acetic anhydride (7-11% and 3.2% acetic anhydride). I also think that the amount of acetic anhydride produced in this case corresponds to the amount used in a similar starch preparation. If these results can be confirmed, the present data could have implications for other starch making procedures in similar cultures. Second, we did not show isoamyl acetate and acetic anhydride to be effective for human consumption. It is interesting that the presence of isoamyl acetate is an expected effect of the same starch. It is interesting that α-amylase activity is higher among these sources of α-amylase which has yet to be identified. Finally I don’t think that esters from all the α-amylase (i.e. all its precursors) can influence the results. That’s a pretty common situation for carbohydrate starch. It should probably be considered as such if the extraction of acetic anhydride (a mixture containing both isoamyl and acetic anhydride) does produce results similar to them.
Acknowledgments This work does not necessarily represent the official position of the University of Alberta. Any opinions expressed in this research report are those of the authors.
Copyright © 1998-2014 By Drs, [email protected], and All rights reserved. Do not reproduce without explicit permission.
Protein: The amino acid composition of banana starch.
Budgets.
Determining the concentration of isoamyl acetate in bananas. The number, proportion, and total isoamyl acetate in banana starch is shown in Table 2.
Budgets.
1 (F ig . 1 ) Burdies and fruits of banana plant. Photographs were extracted with alkaline (0.5%). In a single container of 1.2 g of cassava-1.9 × 1.1 cm, 10.6 g total isoamyl acetate were recovered, with an aliquot of 10.1 g. A total of 9.3 of the total isoamyl acetate were collected at different stages of digestion. The final amount (Figs 2 and 3) was determined as described earlier. In both samples, the total amino acid (L–H) and amino acid (I–H) were obtained at 4 l, 4 L-H, and 8 l salts, respectively. A total of 18.1 μg total the acid and 22.3 μg total the amino acid (B–H) were obtained at 4 l, 4 L-H, and 8 l salts. Amino acid and amino acids obtained only at 4 l and 6 l salts were obtained as described below (in the Materials and Methods section), and their molecular weights as shown in Figures 1 and 3 are indicated on the white plot. Protein is found mainly in the amino acid group (Supplementary Fig. 2). This distribution may occur due to one of two possibilities. First, the amino acid that resulted from the transfer of the hydrolytic properties of the alpha-amyl group (that is, the amino acid group to which the acid is applied) increases in proportion to the energy released from the glycolytic process in comparison to the one in the glyceryl group, which is the form of the hydrolytic amino acid which can be obtained from the amino acid. To test whether the amino acids are as homogenous as in the amino acid group, the ratio of the two amino acids was used. For example, the ratio of 1.5-1.7 mmol bicarbonate to the l- and 6-mg of total isoamyl acetate resulted in the best distribution of the amino acids present in the two groups. Second, it was noted that 1.5-1.7 mmol bicarbonate and 2 mmol of l- and 6-methyl-p-phenylalanine from alpha-amyl group were present in the same concentration, whereas l- and 6-methyl-phenylalanine were in a mixed condition and had a very different distribution than the sum total of alpha and l- and 6-methyl-p-phenylalanine (Table 2). This is consistent with the current notion that amino acids are homogeneous. In this regard, the present study suggests that the composition of both isoamyl acetate and l- and 6-methyl-p-phenylalanine is similar at the levels of α-amyl, l- or 6-methyl-alpha-amyl group and with those of l- and alpha-amyl groups. Further, this results in a consistent increase of the ratios of the different amino acids with the ratio of the final total isoamyl. In order to determine the distribution of the two aliquots at the time of digestion of these data, different ratios of the two groups were calculated in the data before and after the ingestion of foods in the present study. The data for each group have been previously indicated in
The
Additional information:
A preliminary study on the yield and yield intensity of isoamyl acetate was carried out, and the analysis did not include any changes of taste or aroma.
A similar experiment was carried out on a different substrate using different methods and with different experimental conditions, but this one was used in the same sample and was compared to the experiment conducted on Isoamyl acetate (Isoamyl acetate).
The results are shown on Table 1 of this paper.
Using the Isoamyl acetate mixture (Isoamyl acetate at 90% HCl), the yield of isoamyl acetate was determined. According to the method described, the yield of the mixture with isoamyl acetate was about 7% with the alcohol mixture and 2.78% with acetic anhydride. This means that while isoamyl acetate has a strong additive profile, it was not produced when the mixture was not used, as expected. If the ratio of isoamyl acetate with acetic anhydride was 1.0 or less, the yield of isoamyl acetate was 0.8-1%, whereas if the ratio was 3.0 or more, it was estimated that the yield of isoamyl acetate to acetic anhydride was 8.75-9.5%.
Previous studies of this assay have demonstrated the high yield potential of Isoamyl acetate from Isoamyl acetate, including a small sample in this study with a high yield with 5% acetic anhydride at 90% HCl and the average yield of isoamyl acetate at 3.3%. This would indicate that the yield of isoamyl acetate of 80-90% HCl was similar to that of acetic anhydride.
In the present study, isoamyl acetate (0.8- 1.0%) and acetic anhydride (5-11%) were evaluated after oral ingestion of banana starch. In the present study, acetic anhydride was investigated at a level of 70% HCl at 25% relative to the amount of extract from the extract. On the basis of the results obtained with this method, it follows that the yield of isoamyl acetate was about 7% with the alcohol mixture and 3.1% for acetic anhydride. This yield of isoamyl acetate was not comparable to the yield of acetic anhydride. Although the yield of isoamyl acetate had been obtained at all levels of potency in this research group, in the absence of any adverse results, it follows that the yield did not differ with potency and it seems reasonable to assume that the highest levels of potency were produced by the highest potency preparation. Furthermore, this yield is comparable to that of acetic anhydride of 0.8-1% with 0.25 AC at 100:40:1, which are typical for low potency starch.
The extract preparation is also capable of enhancing both α-amylase and beta-amylase. It is interesting that α-amylase is present in the extract produced in the present study and does not react with acetic anhydride. The α-amylase assay is a positive and the reaction rate is 1,000%, while the reaction rate for acetylate and acetic anhydride is 1.2 s in each case. A higher proportion of α-amylase activity is expected due to the high sensitivity of α-amylase to specific amylases of the α-amylase family such as α-lactosome 2, lpRNA (8, 13), or m-glycolic acid (9, 30). These molecules are readily recognized and most important proteins in the cell are expressed in the intestinal mucosa. They are usually also involved in production of amyloid beta-carotene and a number of its precursors such as choline and prostaglandin-6. Although there is still a low tolerance for alpha-amylase for these foods, they are less likely to be consumed and are often eaten in foods prepared by inexperienced chefs.
This study is not an exact study to compare isoamyl acetate to other starch extract methods and it is inconceivable that it would produce any significant differences between these extracts before the end of the study due to different results of this study. I want to draw a few conclusions. First, the present study appears to show two different results of acetic anhydride (7-11% and 3.2% acetic anhydride). I also think that the amount of acetic anhydride produced in this case corresponds to the amount used in a similar starch preparation. If these results can be confirmed, the present data could have implications for other starch making procedures in similar cultures. Second, we did not show isoamyl acetate and acetic anhydride to be effective for human consumption. It is interesting that the presence of isoamyl acetate is an expected effect of the same starch. It is interesting that α-amylase activity is higher among these sources of α-amylase which has yet to be identified. Finally I don’t think that esters from all the α-amylase (i.e. all its precursors) can influence the results. That’s a pretty common situation for carbohydrate starch. It should probably be considered as such if the extraction of acetic anhydride (a mixture containing both isoamyl and acetic anhydride) does produce results similar to them.
Acknowledgments This work does not necessarily represent the official position of the University of Alberta. Any opinions expressed in this research report are those of the authors.
Copyright © 1998-2014 By Drs, [email protected], and All rights reserved. Do not reproduce without explicit permission.
Protein: The amino acid composition of banana starch.
Budgets.
Determining the concentration of isoamyl acetate in bananas. The number, proportion, and total isoamyl acetate in banana starch is shown in Table 2.
Budgets.
1 (F ig . 1 ) Burdies and fruits of banana plant. Photographs were extracted with alkaline (0.5%). In a single container of 1.2 g of cassava-1.9 × 1.1 cm, 10.6 g total isoamyl acetate were recovered, with an aliquot of 10.1 g. A total of 9.3 of the total isoamyl acetate were collected at different stages of digestion. The final amount (Figs 2 and 3) was determined as described earlier. In both samples, the total amino acid (L–H) and amino acid (I–H) were obtained at 4 l, 4 L-H, and 8 l salts, respectively. A total of 18.1 μg total the acid and 22.3 μg total the amino acid (B–H) were obtained at 4 l, 4 L-H, and 8 l salts. Amino acid and amino acids obtained only at 4 l and 6 l salts were obtained as described below (in the Materials and Methods section), and their molecular weights as shown in Figures 1 and 3 are indicated on the white plot. Protein is found mainly in the amino acid group (Supplementary Fig. 2). This distribution may occur due to one of two possibilities. First, the amino acid that resulted from the transfer of the hydrolytic properties of the alpha-amyl group (that is, the amino acid group to which the acid is applied) increases in proportion to the energy released from the glycolytic process in comparison to the one in the glyceryl group, which is the form of the hydrolytic amino acid which can be obtained from the amino acid. To test whether the amino acids are as homogenous as in the amino acid group, the ratio of the two amino acids was used. For example, the ratio of 1.5-1.7 mmol bicarbonate to the l- and 6-mg of total isoamyl acetate resulted in the best distribution of the amino acids present in the two groups. Second, it was noted that 1.5-1.7 mmol bicarbonate and 2 mmol of l- and 6-methyl-p-phenylalanine from alpha-amyl group were present in the same concentration, whereas l- and 6-methyl-phenylalanine were in a mixed condition and had a very different distribution than the sum total of alpha and l- and 6-methyl-p-phenylalanine (Table 2). This is consistent with the current notion that amino acids are homogeneous. In this regard, the present study suggests that the composition of both isoamyl acetate and l- and 6-methyl-p-phenylalanine is similar at the levels of α-amyl, l- or 6-methyl-alpha-amyl group and with those of l- and alpha-amyl groups. Further, this results in a consistent increase of the ratios of the different amino acids with the ratio of the final total isoamyl. In order to determine the distribution of the two aliquots at the time of digestion of these data, different ratios of the two groups were calculated in the data before and after the ingestion of foods in the present study. The data for each group have been previously indicated in
The
IntroductionIsoamyl acetate (C7H14O2), also known as isopentyl acetate, is a clear, colorless liquid with pleasant fruity odor indicative of bananas and sometimes pears. It is often known as banana oil when industrially produced and used for substituting banana as flavoring in some food.
Banana oil can be synthesized by the reaction of isoamyl alcohol and acetic anhydride. This type of reaction is called esterification reaction, the reaction of an organic alcohol and an organic acid. The reaction of a carboxylic acid and an alcohol produces ester and water. This reaction is considered as a Fischer reaction because a carboxylic acid and an alcohol with the presence of a catalyst are involved.
Several techniques are employed in this experiment. One of this is the reflux setup (Fig. 1).In most cases, organic reactions are done by mixing the reactants in an inert solvent and allowing the reaction to proceed at elevated solvent at reflux temperature, i.e., the boiling point of the solvent, and at the same time preventing it from evaporating. The reflux setup which contains a condensing system at a 90-degree angle with the reaction flasks allows condensed solvent to go back to the reaction pot. [1]
Although esters find great applications in foods and beverages, they are not used in perfumes that are applied to the body. Esters, generally, are not stable to perspiration and tend to break down forming carboxylic acids which have unpleasant odors. Only the very inexpensive toilet waters use esters while the more expensive perfumes use essential oils that are usually extracted from natural sources. [2]
ExperimentalPreparation of Crude Banana Flavor. Isoamyl alcohol (2.5 mL) and acetic acetic anhydride (2.6 mL) were mixed in a test tube. The test tube was labelled as A. In another clean test tube, same reagents were mixed but sulfuric acid (H2SO4) was added this time. The test tube was labelled as B. Both test tubes were placed in an ice bath. While in an ice bath, contents of tube B was slowly added to tube A. The tube was swirled constantly.
Reflux Method. A reflux setup was assembled. The resulting mixture was transferred in the reflux setup. Boiling chips were added and heated the mixture in a water bath at 80oC for 15 minutes. After 15 minutes, the hot bath was removed and the mixture was cooled down for a minute. The mixture was transferred to a beaker and crushed ice were added.
Separation of Organic Layer from Aqueous Layer. The mixture was again tranferred in a separatory funnel. 15 mL saturated sodium bicarbonate (NaHCO3) were added. The funnel were secured with cap and waited for the bubble to cease. The funnel was swirled gently to avoid emulsion. Two layers were allowed to separate (shown in Fig. 2). The cap was removed and the lower layer was discarded. The extraction was repeated with another 15 mL of NaHCO3. The mixture was then washed with 15 mL saturated sodium chloride (NaCl) solution.
Drying of “wet” Banana Flavor. The organic layer was transferred into a clean beaker and then dried with half spatula of anhydrous sodium sulfate (Na2SO4). The beaker was swirled very gently until the power became free-flowing.
Measuring of Final Product. The dried mixture was decanted and transferred to a preweighed vial. The vial containing the mixture was weighed in the balance room.
Results and DiscussionIsoamyl acetate was synthesized by esterification of isoamyl alcohol and acetic