The Effects of Replacing Butter with Plant Sterol Containing Margarine in Dinner Rolls. Stephanie Stromp F&N 453 Fall 2007

Transcription

1 The Effects of Replacing Butter with Plant Sterol Containing Margarine in Dinner Rolls. Stephanie Stromp F&N 453 Fall 2007

2 Abstract: The purpose of this experiment was to determine the effects of replacing butter with plant-sterol containing margarine (Promise Activ) on the texture and sensory appeal of dinner rolls. A recipe found online was modified to contain three variations of butter and/or margarine content: all butter, ½ butter-½ Promise Activ, and all-promise Activ. Three trials of each variation were completed, texture analysis and water activity were determined from samples of each variation, and the products were presented to subjects for make decisions of preference and appeal. The results showed that the dinner rolls containing all Promise Activ-containing rolls had the softest texture, highest water activity, and highest consumer appeal and preference. These results could be helpful in promoting diets higher in plant sterols, which could lead to a decrease in cholesterol, correlating with a decreased risk for coronary heart disease (CHD).

3 Introduction: High serum cholesterol has been correlated with an increased risk for developing coronary heart disease (CHD), and is a serious health issue of rising prevalence in the United States. Increasing interest in the effects and benefits of plant sterols in the diet have lead to further research, and is the basis for this experiment. Phytosterols found in plants have a similar structure to endogenous cholesterol and can therefore compete with molecule for absorption into the small intestine. This effectively lowers the amount of cholesterol returning to the liver thereby decreasing serum cholesterol levels which are directly related to CHD risk (Functional Foods, 2006). The FDA has released information stating that to see a significant decrease in serum cholesterol; an intake of 1.3 grams per day of plant sterols, or 3.4 grams per day of plant stanols is needed. Following this guideline, a food product must contain at least.65 grams per serving of plant sterols or at least 1.7 grams per serving of plant stanols to be considered effective in reducing cholesterol (Welch, 2000). It is also required for the claim made on the food to state that the intake of the sterols or stanols should be in two servings at different times of the day, and consumed with other foods. The USDA has conducted a research study that shows the effects of incorporating plant sterols in the diet. Two groups both eating low-fat diets, used salad dressings either with or without plant sterols for three weeks of a six-week study. While the typical American diet contains approximately.25 grams of plant sterols daily, the selected group in the study consumed 2.2 grams per day for the duration of the three-week dietary intervention. At the end of the study, the low-fat diet alone was responsible for a drop in bad cholesterol of 7.3 and 8.4 percent, while the plant sterols nearly doubled the

4 decrease with 14.1 and 18.2 percent drop (De Quattro, 2000). In both groups, the levels of HDL remained the same. The purpose of this project was to examine the hypothesis that the substitution of plant sterol-containing margarine for butter will have an effect on the texture and sensory appeal of dinner rolls. The independent variables include the varying levels of butter and margarine, all the other ingredients in the recipe, methods used in preparing the food product, and equipment and materials used. The dependent variables measured were strength, which was determined by Texture Analyzer, water activity, and subjective measures including relative preference and perceived texture. The results can be seen in the tables and figures at the end of this report and will be discussed thoroughly later in this text. There are some crucial chemical and physical reactions that occur to ensure proper bread dough formation. The yeast used in the recipe is necessary to form carbon dioxide, which is then trapped within the dough, causing it to rise. The formation of gluten is necessary to trap the gas in the dough, and is formed through the interaction of gliadin and glutenin, which are found in the included flour. Kneading of the wet dough enables the contact between the two proteins, and is therefore essential in the making of bread dough (Barham). Other suggestions for making bread are to use a strong flour, as it will have a higher gluten-forming potential, to knead the dough thoroughly, let it rise for plenty of time, and to knock it down and let it rise again at least once before cooking. Methods: The recipe being used is for dinner rolls and it comes from the Allrecipes Tried and True Favorites cookbook.

5 Yield: 16 servings 180 ml milk 180 ml water 100 g white sugar 6 g salt 2 eggs 20 g active dry yeast 625 g all-purpose flour 110 g margarine Preparation: Warm milk, water sugar and salt in a saucepan over medium heat. Then, remove mixture from heat and add the eggs and yeast. Measure flour into a large bowl, make a well in the middle, and pour the milk mixture into it. Without mixing, cover the bowl, and let stand for minutes. Pour the melted margarine into the flour and mix well, adding more flour if the mixture is too sticky. Knead lightly and cover again, letting stand and rise for minutes. Then, form the dough into evenly sized rolls, and place onto a baking sheet, and let rise again for minutes. Then place the baking sheet(s) into a preheated oven of 400 degrees F (205 degrees C) and bake for 15 minutes, or until done (Margaret). As mentioned before, for each trial, three versions of the recipe were compared. The recipes for each variation, per trial are as follows: ALL BUTTER: ½ and ½: 90 ml milk 90 ml milk 90 ml water 90 ml water 50 g white sugar 50 g white sugar 3 g salt 3 g salt 1 eggs 1 eggs 10 g active dry yeast 10 g active dry yeast 310 g all-purpose flour 310 g all-purpose flour 55 g real butter, melted 27.5 g real butter, melted 27.5 g margarine w/ plant sterols, melted

6 ALL MARGARINE: 90 ml milk 90 ml water 50 g white sugar 3 g salt 1 eggs 10 g active dry yeast 310 g all-purpose flour 55 g margarine w/ plant sterols, melted The margarine chosen for this experiment is called Promise Activ Spread, which used to be called Take Control since each serving contains 1.0 g of plant sterols (Promise). Instead of using plastic lids as suggested, plastic wrap was used due to the materials available, as well as to make the process easier to replicate. The texture analyzer was set on bread for the reading, and the cone probe was used. For each variation, the same preparations were used, including a uniform sitting/rising time of 30 minutes, and cooking time of 15 minutes. To control other variables, the three variations will be made at the same time in the same conditions, and identical supplies will be used for every repetition. For each trial, the different variations were placed in different places on the baking sheets, which were recorded each time so the rolls could be uniformly rotated through each of the three locations. A sample of each variation was used for the texture analyzer and water activity measurements, which were repeated three times each and averaged. At the end of the three trials, the values were averaged again for an overall comparison. When given to the subjects for sensory evaluation, the three numbers (422, 177, and 311) were rotated throughout the samples for each trial as well. In this way, no variation had the same number twice when the subjects tasted them, reducing bias of the responses. The subjects recorded their opinions based on a hedonic scale and a

7 preference test. The results from all of the analyses are discussed and shown later in this report. Discussion: Fats play a few critical roles in the development of bread dough, affecting the flavor, texture and sensory appeal of the final product. Lipids act to break the strand of gluten into smaller pieces, preventing the bread from attaining as much volume (Ingredients). This could have been the reason for the smaller, chewier products in the second and third trials. It could also account for the differences between the products containing butter compared to the products containing margarine due to different interactions with the gluten proteins. Kneading is an important step in proper bread dough formation because it allows for the full development of gluten. This allows the fullest rising capacity of the bread by enabling more air to be trapped and distributed throughout the dough while simultaneously dispersing the ingredients the yeast feed on, allowing a higher level of fermentation. The resulting product will have a lighter, fluffier texture. A recommended eight to ten minutes of kneading will permit the best gluten formation and best rising capacity (Bread). This could have also been a problem in the case of this experiment, resulting in the tough, doughy products. The variable should have been controlled better and could have been done so by timing and regulating the kneading for each variation. Further investigations controlling this variable would produce more appealing products and would be more useful for comparisons. Another possible source of error is related to the water activity machine, as the mechanism of notification did not work properly, and it was not consistently possible to

8 know when the test was complete. This would create adverse values for the results and would affect the outcomes of the comparisons between samples. The major problem regarding the sensory panel results is that the samples were not very appealing to begin with. This could have been due to one of the possible problems discussed previously, and potentially significantly skewed the results.all of the problems that have been discussed could be bases for further experimentation and investigation. Controlling for specific variables would radically help in answering the many questions involved with this area of research. The fact that the end products did not show very much sensory appeal would indicate the need for further research. If more solid evidence could be found, the claims that could be made about the convenient use and benefits of plant sterol-containing margarine would be more justifiable and could potentially hold more influential power in convincing the public to change their dietary habits.

9 Results: The results of all three trials show the similar results of the rolls containing all Promise Activ to have the lowest value from the texture analyzer and a relatively high level of water activity. Trial 1 clearly shows the inverse relationship between texture and water activity of the three different rolls, with the results being shown in Table 1. The comparison of the three variations can be seen in figures 1.1 and 1.2. The data from trials 2 and 3 can be seen in tables 2.1 and 3.1, with the results compared in figures 2.1, 2.2, 3.1 and 3.2. The total, average results of each variation are shown in table 4.1, with the averages for the individual variations across the three trials in tables 5.1, 6.1, and 7.1.Figures 5.1, 5.2, 6.1, 6.2, 7.1 and 7.2 show the comparisons of results for the individual variations across the trials. The experiment would have been more successful if the results remained relatively consistent for each variable. Overall, the data from the experiment showed that the rolls containing all Promise Activ had the softest texture and highest water activity. In general, the all-butter rolls showed the lowest rating of sensory appeal, and the all-promise Activ rolls showed the highest. These results could be the starting point for further investigations that could potentially hold significant value when making recommendations for the public. M ore information is needed regarding the differences between using butter and margarine in this recipe for dinner rolls. However, even though the end products were not as desirable as expected, the results can successfully show that if anything, no adverse effects results from using plant sterol-containing margarine. This could be useful in making recommendations for the public to easily increase dietary consumption of plant sterols to

10 effectively reduce cholesterol.

11 References: Barham, Peter. Breads. The Science of Cooking. Springer, "Bread Baking 101." Baking Oct De Quattro, Jim. New USDA Study Shows Plant Sterols Lower Cholesterol. April 18, United States Department of Agriculture. Functional Foods Fact Sheet: Plant Sterols and Stanols. International Food Information Council Foundation Higdon, Jane. Phytosterols Micronutrient Information Center. Linus Pauling Institute, Oregon State University "Ingredients - Bread." Science Toys. 20 Oct Margaret, Sherlie. Unbelievable Rolls. Allrecipes Tried and True Favorites Cookbook "Promise Activ Buttery Spread." Promis Healthy Heart. 20 Oct Thompson, Stephanie. Lipton to Control Margarine Launch Plan. Brandweek. Nov. 30, BPI Communications Inc. Welch, Ruth. FDA Authorizes New Coronary Heart Disease Health Claim for Plant Sterol and Plant Stanol Esters. FDA Talk Paper, Sept. 5, Food and Drug Administration.

12 Tables and Figures -TRIAL 1- Table 1.1 Obtained average values for TA (g) and A w of dinner rolls with different butter and margarine composition in Trial 1. Composition TA (g) Aw all butter /2 and 1/ all Promise Activ Texture of Dinner Rolls in Trial 1 TA (g) all butter 1/2 and 1/2 all Promise Activ Composition Figure 1.1 Obtained average values for TA (g) of dinner rolls with different butter and margarine composition in Trial 1.

13 Aw of Dinner Roles in Trial 1 Aw all butter 1/2 and 1/2 all Promise Activ Composition Figure 1.2 Obtained average values for A w of dinner rolls with different butter and margarine composition in Trial 1.

14 -TRIAL 2- Table 2.1 Obtained average values for TA (g) and A w of dinner rolls with different butter and margarine composition in Trial 2. Composition TA (g) Aw all butter /2 and 1/ all Promise Activ Texture of Dinner Rolls in Trial 2 TA (g) all butter 1/2 and 1/2 all Promise Activ Composition Figure 2.1 Obtained average values for TA (g) of dinner rolls with different butter and margarine composition in Trial 2.

15 Aw of Dinner Rolls in Trial 2 Aw all butter 1/2 and 1/2 all Promise Activ Composition Figure 2.2 Obtained average values for A w of dinner rolls with different butter and margarine composition in Trial 2.

16 -TRIAL 3- Table 3.1 Obtained average values for TA (g) and A w of dinner rolls with different butter and margarine composition in Trial 3. Composition TA (g) Aw all butter /2 and 1/ all Promise Activ Texture of Dinner Rolls in Trial 3 TA (g) all butter 1/2 and 1/2 all Promise Activ Composition Figure 3.1 Obtained average values for TA (g) of dinner rolls with different butter and margarine composition in Trial 3.

17 Aw of Dinner Rolls in Trial 3 Aw all butter 1/2 and 1/2 all Promise Activ Composition Figure 3.2 Obtained average values for A w of dinner rolls with different butter and margarine composition in Trial 3.

18 -OVERALL AVERAGES- Table 4.1 Obtained average values for TA (g) and A w of dinner rolls with different butter and margarine composition from Trials 1, 2 and 3. Composition TA (g) Aw all butter /2 and 1/ all Promise Activ Average Texture of Dinner Rolls from Trials 1, 2 and 3 TA (g) all butter 1/2 and 1/2 all Promise Activ Composition Figure 4.1 Obtained average values for TA (g) of dinner rolls with different butter and margarine composition from Trials 1, 2 and 3. Aw of Dinner Rolls from Trials 1, 2 and 3 Aw all butter 1/2 and 1/2 all Promise Activ Composition Figure 4.2 Obtained average values for A w of dinner rolls with different butter and margarine composition from Trials 1, 2 and 3.

19 - ALL-BUTTER ROLLS- Table 5.1 Obtained average values for TA (g) and A w of all-butter dinner rolls from Trials 1, 2 and 3. Trial TA (g) Aw Texture of All-Butter Dinner Rolls in Trials 1, 2 and 3 TA (g) Trial Figure 5.1 Obtained average values for TA (g) of all-butter dinner rolls in Trials 1, 2 and 3. Aw of All-Butter Dinner Rolls in Trials 1, 2 and 3 Aw Trial Figure 5.2 Obtained average values for A w of all-butter dinner rolls in Trials 1, 2 and 3.

20 - ½ AND ½ ROLLS- Table 6.1 Obtained average values for TA (g) and A w of ½ butter, ½ Promise Activ-dinner rolls from Trials 1, 2 and 3. Trial TA (g) Aw Texture of 1/2 and 1/2-Dinner Rolls in Trials 1, 2 and TA (g) Trial Figure 6.1 Obtained average values for TA (g) of ½ butter, ½ Promise Activ-dinner rolls in Trials 1, 2 and 3. Aw of 1/2 and 1/2-Dinner Rolls in Trials 1, 2 and 3 Aw Trial Figure 6.2 Obtained average values for A w of ½ butter, ½ Promise Activ-dinner rolls in Trials 1, 2 and 3.

21 -ALL PROMISE ACTIVE ROLLS- Table 7.1 Obtained average values for TA (g) and A w of all Promise Activ-dinner rolls from Trials 1, 2 and 3. Trial TA (g) Aw Texture of All-Promise Active Dinner Rolls in Trials 1, 2 and TA (g) Trial Figure 7.1 Obtained average values for TA (g) of all-promise Activ dinner rolls in Trials 1, 2 and 3. Aw of All-Promise Activ-Dinner Rolls in Trials 1, 2, and 3 Aw Trial Figure 7.2 Obtained average values for A w of all-promise Activ dinner rolls in Trials 1, 2 and 3.