The Effect of Green Tea on the Texture, Taste and Moisture of Gharidelli Double Chocolate Brownies

Transcription

1 Katie Mitsch Madison Moore FN 453 The Effect of Green Tea on the Texture, Taste and Moisture of Gharidelli Double Chocolate Brownies Introduction: The Center for Disease Control states that cancer and cardiovascular disease are the top two leading causes of death, killing over a million people each year (CDC, 2010). With the recent studies that have been conducted on green tea, the results show that there is a negative correlation with these diseases. Also, The consumption of green tea beverage and green tea extracts have been found to have excellent effects on management of weight, as well as decreasing fat in the body. There has been scientific evidence that drinking green tea improves thinking skills and might help lower cholesterol, and to help prevent or delay Parkinson s disease and other cancers. In the 1994 Journal of the National Cancer Institute showed results that in an epidemiological study that drinking tea reduced the risk of esophageal cancer in Chinese men and women by sixty percent. Also Purdue University researchers concluded that a compound founded in green tea inhibits the growth of cancer cells. Another benefit associated with consuming green tea is the effects of weight management. A study conducted at Oklahoma State University titled Green tea supplementation affects body weight, lipids, and lipid peroxidation in obese subjects with metabolic syndrome which focused on the decrease in LDL cholesterol of the subjects being tested. The objective of the experiment was to compare the effects of supplementation of green tea beverage or green tea extracts with controls on body weight, glucose and lipid profile, biomarkers of oxidative stress, and safety parameters in obese subjects with metabolic syndrome (J Am Coll Nutr Feb;29(1):31-4). Researchers randomly selected thirty-five obese men and women diagnosed with various metabolic syndromes. The experiment consisted of three groups: 1) the control (4 cups water/d), 2) green tea (4 cups/d), or 3) green tea extract (2 capsules and 4 cups water/d) group. Each subject was instructed to consume, depending on which group they were in, either 4 cups of water (group 1), 4 cups of green tea beverage (group 2), or 2 green tea extract capsules and 4 cups of water (group 3). No specification on when to consume the assigned beverages during each day of the 8-week experiment. The results for the experiment consisted the green tea beverage and green tea extracts causing a significantly measurable decrease in body weight as well as body mass index (BMI). Furthermore, groups that consumed the green tea beverage and the green tea extract had decreased LDL levels after the 8 weeks, compared the control group. The experiment was a significant indication consumption of green tea would help decrease LDL levels as well as helping maintain a healthy body weight. Another noteworthy finding from the research is that the green tea beverage group as well as the green tea extracts group displayed a decrease in lipid peroxidation. Lipid

2 peroxidation refers to the degradation by oxidation of fat cells. Individuals with metabolic syndromes have an increase in lipid peroxidation because it causes cell damage. Flavonoids are the protecting agents found in green tea and they keep cells from starting the lipid peroxidation process. For this reason, decreases in lipid peroxidation are significantly important for obese patients with metabolic syndromes. The hypothesis for this experiment was the amount and presence of 100% brewed green tea will not have an effect on the texture, taste and moisture of Gharidelli double chocolate brownies. The independent variable in the experiment is the varying amount of 100% brewed Lipton Green Tea in each batch of brownies. The dependent variables of the experiment are texture, taste and moisture in each batch of brownies. The primary goal of the experiment was to create a tasty, desirable snack that contained a descent amount of green tea, so consumers may be more apt to reap green tea s health benefits. A taste panel tested the each set of brownies for moisture and taste. The objective test was using the Texture Analyzer on each batch of brownies. The control group was the batch of brownies that contain no brewed green tea. The results of each test were compared to this control group. Methods: Standard recipe: 1 box Gharidelli Double Chocolate mix 1/3 cup water 1/3 cup vegetable oil 1 egg Preheat oven to 325 o. Lightly spray baking pan with non-stick cooking spray. Blend 1/3 cup water, 1/3 cup vegetable oil and 1 egg in medium bowl. Add brownies mix and stir until moistened (about 40 strokes). Spoon batter into prepared baking pan and spread evenly. Bake Do not overbake. Fresh-baked brownies appear underbaked but cool to doneness. Cool completely in pan before cutting. 50/50: 1 box of Ghiradelli Double Chocolate mix 1/6 cup water 1/6 cup of brewed 100% natural Lipton Green Tea 1/3 vegetable oil 1 egg 100: 1 box Ghiradelli Double Chocolate mix 1/3 cup of brewed 100% natural Lipton Green Tea 1/3 cup of vegetable 1 egg Objective testing:

3 To determine the changes in texture the Texture Analyzer was used with the cylinder probe. The cylinder probe came in contact with the top portion of three different brownies of each of the three different batches that were made with the 100% natural Lipton Green Tea. Replication, randomization, and sampling: All three of the variables were replicated three different times using the same method each and every time to ensure there was uniformity. The three different numbers that were used were, 345, 239, and 456. While preparing for the subjective portion of the testing we set up a triangle test on the plate Discussion: The results of the experiment were that the addition of the green tea to both of the different variables 2 (1/6 cup), and 3(1/3 cup) did not have an effect on most of the subjective, but all of the objective measurements. Changes in the hardness and palability were not apparent in the subjective measurement nor was it noted in the objective testing. Many of the panelists seemed to prefer the palability of Variable 2, with half green tea, half water, compared to the other variables 1 and 3, as noted in Table 3 and Figure 3. These subjective results were measured by numerically ordering the three different samples of brownies from 1 to 3 with 1 being the variable the panelist who sampled the brownies liked the most and 3 being the sample that was least liked. Figure 2 and Table 2 showed the results of the sample brownies based on its hardness. The subjective results were measured on a hedonic scale where the panelist who sampled the brownies rated those 9 as extremely hard and 1 as extremely soft. Looking at Figure 2 it can be seen that there is no significant difference between the three variables. Although there was no significant difference between the variables, variable 2 (1/6 cup) was ranked the number for being the hardest out of the three variables and variable 3 (1/3 cup) was ranked third in hardness, which can be seen in table 2 s averages. In the subjective test where the panelists were asked if they tasted a difference between the different samples of brownies, the p value the variables when compared to each other were p<.08, which would mean that there was no significant difference. They can be seen

4 in figure 3. This shows that each brownie did not have its own unique flavor even though different amounts of green tea were added. The objective test with the Text Analyzer showed the hardness of the brownies. The texture analyzer consisted of a moving crosshead that compresses or extends the brownie, a load cells measured the force, the cone probe for testing the hardness, and showed the results on the computer (Daniels, JR, 2010). The difference between the control and the two variables was not significant. Even though there was no significant difference between the variables and the control, the control did have the highest average, which can be seen in table 1. The a values showed that there was no significant different between the three variables. Figure 1 seems to demonstrate that as the amount of brewed green tea is added to the brownies it does not need more force to penetrate the brownies. This may be because another liquid, and not a dry ingredient, such as green tea powder, is replacing a liquid. The measurements gathered from the texture analyzer showed that the control and the other two variables did not have a significant difference with the p value of p<.3. This shows that the amount of force needed to penetrate the brownies did not significantly increase with the added amounts of 100% brewed green tea. The implementation of 100% brewed green tea into many different foods, such a brownies, can greatly improve the overall health status of individuals by providing different benefits, such as antioxidants in food items individuals enjoy. Another idea to add with incorporating would be to see if there would be any effect on the food item by adding a no calorie sweetener, like Splenda, with the green tea. Adding this ingredient could help the consumers enjoy the product much more. Increasing the number of panelist would allow there to be more feedback and data about the experiment. For objective tests another test that could be done would be a ph test and that could be very helpful in identifying the bitterness of the product. Results: Table 1: Grams of force measured with the Texture Analyzer for all trials and variables. Trial grams 3.87 grams 4.08 grams Trial grams 4.18 grams 4.28 grams Trial grams 4.18 grams 4.18 grams Average 4.31 grams 4.08 grams 4.18 grams Standard Deviation Table 2: Significance testing for Texture Analyzer

5 4.31a 4.08a 4.18a *Means not bearing the same letter are significantly different, p< Grams of Force Grams of Force control 50% 100% Variable Figure 1: Average grams of force for all three trials Table 3: The average subjective preferences of each variables hardness for all three trials based on a 9-point hedonic scale with 1 being the most desirable and 9 being the lease desirable. Trial Trial Trial Average Standard Deviation Table 4: Significance testing for moisture 4.25a 4.83a 3.92a *Means not bearing the same letter are significantly different, p<.05.

6 Moisture Hardness 0 Control 50% 100% Variables Figure 2: Results from subjective testing for moisture from the average of the three trials. Table 5: The average subjective preferences of each variable for palability of all three trials based on a 3 point hedonic scale with 1 being the most palatable and 3 not being the most palatable. Trial Trial Trial Averages Standard Deviation

7 Palability Palability Control 50% 100% Variable Palability Figure 3: Results from subjective testing for palability from the average of the three trials. Table 6: Significance testing for palability 1.50a 2.42ab 2.08b *Means not bearing the same letter are significantly different, p<.05. References: Basu A, Sanchez K, Leyva M.J., Wu M., Betts N.M., Aston C.E., Lyons T.J. Green tea suppl.mentation affects body weight, lipids, and lipid peroxidation in obese subjects with metabolic syndrome. Journal of the American College of Nutrition Feb;29(1): Center for Disease Control and Prevention. Death and Mortality Retrieved Sept.26, Chacko, S.M., Thambi, P.T., Kuttan, R., Nishigaki, I., Beneficial Effects of Green Tea: A Literature Review Chinese Medicine. Vol. 5:13. Stendell-Hollis, N. R, Thomson, C. A., Thompson, P. A., Bea, J. W., Cussler, E. C. and Hakim Green tea improves metabolic biomarkers, not weight or body composition: a pilot study in overweight breast cancer survivors. Journal of Human Nutrition and Dietetics, Issn x