Food MicroBiology: Color Evaluation of Food

Laboratory 1. Color and Appearance

This lab is Sensory Evaluation, there were five tests performed.

We have to include this information in the lab report:

1. Title Page
2. Abstract Page
3. Introduction or Literature review on the color evaluation of food, the test performed, and maybe talk about sensory evaluation of color when it comes to foods. Please be creative!!!!
4. Methods, which have to be in your own words and can’t be copied and pasted from original methods.
5. Results and Discussion of each test
6. Tables have to be labeled properly. I will email these files to customer support to send over to you.  Please include  in the report with the data that were gathered for each test. Also, if you can include a color chart that is used in Sensory Evaluation for food and make sure you reference it.
7. References :Any Information or references used outside the report has to be referenced.
8. Conclusion ( in this section, include your conclusion on each test)

Test Performed

1. Triangle Test- During the test we had the 3 samples in front of us on our desk with a white tri-fold cardboard to block everyone from seeing our samples and our results from the evaluation. We also had white paper to write our data on each test. You have 3 clear plastic cups with lids that you can see through all filled with purple Blueberry yogurt.

Out of the three samples( two cups of yogurts are Walmart Great Value Blueberry Yogurt ( which are sample codes: 638 and 841 are the same ) and 1 cup of yogurt is an Activia Blueberry Yogurt – which is sample 042 ). Which is the odd one out? ( sample 042 ) See your samples from left to right, you can go back to repeat the evaluation if you need too. Indicate which two codes are similar and which is the odd sample. So, sample 638 and 841 were both the Walmart Great Value Yogurts, both a purple color and they both seem lighter in color and visually they looked the same as far as texture too (very creamy looking). The odd sample was 042 which ended up being the Activia Blueberry Yogurt which was purple as well and it was much darker in color and runny in texture and wasn’t as creamy. The professor said the point of this test was to observe the yogurts from a visual and color prospective and determine how the 3 yogurts even though two different brands and you have to figure out which ones, appealed to you visually and that’s how you were able to match 638 with 841 and 042 being the odd sample out.

2. Duo-Test: During the test we had the 3 samples in front of us on our desk with a white tri-fold cardboard to block everyone from seeing our samples and our results from the evaluation. We also had white paper to write our data on each test. You have 3 clear plastic cups with lids that you can see through all filled with ketchup. The sample in the top of the triangle is the same as one of the other two. Which one is it? Out of the three samples one is your control ketchup and it says control( which is Hunt’s Ketchup) and then one sample is 315 (being a Hunt’s Ketchup) and it’s the same as your control and sample 530( Walmart Great Value Ketchup). So, the control and 315 both look the same in color and consistency and they seem thicker in texture and it’s not flat. Sample 530 is different from the control and sample 315. Sample 530 looks darker in color than the other 2 samples and it seems flat and a little watery.

The point of this test was also to pay attention to color and appearance when making your decision.

3. Ranking Test

During the test we had the 4 samples in front of us on our desk with a white tri-fold cardboard to block everyone from seeing our samples and our results from the evaluation. We also had white paper to write our data on each test.  You have 4 clear plastic cups with lids that you can see through all filled with some type of Orange Juice. The juices used were Orange H-Ci, Fresh Squeezed Orange Juice, Minute Maid Orange Juice, and Reconstituted  Tang( which was watered down. The sample numbers are 460, 691. 839, and one cup listed as just frozen (with some type of Orange juice in it). The professor never shared which juice goes with which sample in the end, the test was to determine which cup you preferred by how the juice appealed to you and the visual color.  I picked 839 as number 1 because it was bright orange and thicker than the other 3 orange juices. Second, I chose 460 because this sample is not as bright as 839, but brighter than the other samples. And still a thicker sample than the frozen and 691 sample. Third, I chose 691 because this sample is not as thick as 839, 691, but thicker than the frozen sample. And still has a vibrant color. Fourth, I chose the Frozen sample because it seems runnier than the other samples and the color is very light orange and not very thick in texture.

The Ranking test was based on preference, color, and appearance

4. Volume Evaluation Using the Standing Height and Displacement Methods

On this section, I will upload in files so you can see the direction and this test was written out better than the other 3 tests. Within this Volume Evaluation, first you have Volume Evaluation by the Displacement Method. See the uploaded file for steps 1 through 6 on this test( include in report). So, after the procedure 1-6 was performed, my results were 850 ml of measured bird seed obtained from the silver bowl and then 700 ml of measured bird seed after adding the muffins to the silver bowl. Then from these two finding, you take the difference of the two which is  and divide by 2, which is 150 and divide  by 2 again to get the displacement of the two, which is 75 ( the average of each muffin).

Second part to this is Standing Height Evaluation

On this section, I will upload in files so you can see the direction and this test was written out better than the other 3 tests. Within this Volume Evaluation, second you have Standing Height Evaluation.  See the upload file for steps 1 through 3 on this test ( include in lab report) and I will upload a picture I took on the board showing how we used the clear ruler to measure the muffins at points A, B,C,D, E. In this test, we were given a clear ruler and a white plate with two muffin on it and two numbers on the plate(105 and 726 and the two muffins sitting on top of the numbers) one muffin (labeled 105- a Mixed Blueberry Muffin from a box) and another muffin( labeled 726- a Homemade muffin). We were given a butter knife and had to split each muffin down the middle and measure one side of these two different muffins

For muffin 105:

1. 3 cm

B.4 cm

1. 4 cm

D.4 cm

1. 3 cm

*Calculate the values for each muffin and then do the average

Make sure to include all the information I will upload in files about this section from steps 1-3:

Volume Index = 12

Symmetry Index = 0

Uniformity Index = 0

For muffin 726:

1. 3 cm
2. 4 cm
3. 4.5 cm
4. 4.5 cm
5. 1.5 cm

*Calculate the values for each muffin and then do the average

Make sure to include all the information I will upload in files about this section from steps 1-3:

Volume Index = 13

Symmetry Index = 0.5

Uniformity Index = 0.5 ( I got -0.5) but professor told me to just put 0.5

5. Color Evaluation of Food with the CR- 410 Colorimeter
6. In this test, we have a station set up with a CR-410 Colorimeter and three petri plates with clear lids on them of the yogurt sample, mustard sample, and Hunt’s ketchup sample.
7. With the colorimeter, I place the base of it directly into the sample and wrote down the color value( L, a, b) of each sample which was obtained from the screen of the colorimeter after pushing the key “color”. I wrote the average for each color value. Please put it in a Table titled: Average color values of food products tested with a CR-410 Colorimeter and include all data in the table.

Results:

Yogurt Sample:

L = 73.53

a= 15.05

b= 5.04

Mustard

L = 68.39

a = 2.48

d = 35.67

Hunt’s Ketchup

L = 27.54

a =21.45

b = 10.00

Please let me know if there is something that you don’t understand !!!! P.S use any insight that you may have with Food Microbiology and anything you about this lab from experience.Thanks