FST528 exp 7 - lab report PDF

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INTRODUCTION Bread usually can last from a few days to few weeks with the help of preservatives. Propionic acid is the common preservative used in the baked goods to prevent the food spoilage that caused by the growth of molds (James P.S., 2017). According to Malaysian Food Regulations 1985, bread may contain propionic acid and its sodium, potassium or calcium salts, not exceeding 2000 mg/kg of bread as permitted preservative and any preservatives is added with an extremely low concentration and should not impart color, flavor or taste of the product (Food Act 1983 & Regulations, 2017). Preservatives are most commonly used to control mold growth in baked goods. Propionic acid which is an aminocarbolic acid (CH3CH2-COOH), is a naturally occurring organic acid and is an oily liquid with a slightly pungent, disagreeable rancid odor. Its salts are white, free-flowing powders with a slight cheese like flavor. This acid or its salt can be used to prevent the bacterial spoilage of bread known as rope caused by certain Bacillus sp (Kumar D.P., et al., 2015). Propionic acid is generally recognized as safe for us in food. The propionic dispersed easily in basic dough ingredients. They do not alter color, taste, volume or baking time at the levels commonly used. It is also not toxic to human but does prevent them from reproducing and posing a health risk to humans (James P.S., 2017). Thus, this experiment is conducted to determine the effect of calcium propionate on the shelf life of bread. The hypothesis for this experiment is the more concentrate calcium propionate, the harder the bread to spoilage.

OBJECTIVE To determine the effect of calcium propionate on the shelf life of bread.

MATERIALS Formulation High protein flour Water Instant yeast Salt Sugar Shortening Calcium propionate

EQUIPMENT 1) Baking oven 2) Dough mixer 3) Baking tray

Control 1000 600 15 15 30 30 -

F1 1000 600 15 15 30 30 200ppm

F2 1000 600 15 15 30 30 1000ppm

METHOD

1. Calcium propionate was dissolved in water.

2. All dry ingredients was mixed in a dough mixer. Then, calcium propionate and water mixture were slowly added.

3. Then, it was mixed using slow speed for 2 minutes and medium speed for the next 10 minutes to form a dough.

4. Dough was placed in a container and covered with moist cloth. The dough was let to rise aounf 45 minutes to a double size. 5. The dough was punched and shape into round balls of approximately similar size. The dough was placed into a greased pan. 6. Final proofing for 45 to 60 minutes (35 to 37°C; 95% RH). The dough was baked in an oven at 180°C for 30 to 35 minutes.

7. The balls was arranged on a rack for cooling. Once cooled it was packed in PE plastic bags and sealed.

8. The overall appearance was evaluated and was observed for signs of mold spoilage every day according to Table 1.1.

9. The observations was recorded and the results was discussed in the Results Data Sheet.

RESULT Table 1.1: Indicator Codes for bread signs of spoilage Surface Mold Growth

Off-Odor

1. No surface mold observed

1. Fresh odor

2. Small amount of mold ( ¼ but < ½ of bread

3. Moderately off-odor 4. Extremely off-odor

surface) 4. Excessive amount of mold (> ¼ of bread surface) Texture Changes

Overall Acceptability

1. Soft

1. Extremely dislike

2. Slightly hard

2. Moderately dislike

3. Moderately hard

3. Moderately acceptable

4. Extremely hard

4. Highly acceptable

Table 1.2: Observation data for bread sign of spoilage without calcium propionate Signs of Spoilage Day

Surface Mold

0

Growth 1

1

Overall

Texture Changes

Off-Odor

1

1

Acceptability 4

1

1

1

4

2

1

1

2

3

3

1

2

2

3

4

2

2

2

2

5

2

2

2

2

6

2

3

3

2

7

3

3

3

2

8

2

3

3

1

9

3

3

3

1

10

4

3

3

1

Table 1.3: Observation data for bread sign of spoilage with 200 ppm calcium propionate Signs of Spoilage Day 0

Surface Mold Growth 1

1

1

1

1

4

2

1

2

2

3

3

1

2

2

3

4

2

2

2

3

5

1

2

2

2

6

2

3

3

2

7

2

3

3

2

8

2

4

3

1

9

3

4

3

1

10

3

4

3

1

Texture Changes

Off-Odor

1

1

Overall Acceptability 4

Table 1.4: Observation data for bread sign of spoilage with 1000 ppm calcium propionate Signs of Spoilage Day

Texture Changes

Off-Odor

1

1

Overall Acceptability 4

0

Surface Mold Growth 1

1

1

1

1

4

2

1

1

1

4

3

1

1

1

4

4

1

1

1

3

5

2

2

2

2

6

2

3

2

2

7

2

3

3

2

8

3

3

3

2

9

3

3

3

2

4

4

4

1

10 DISCUSSION

Bakery products are subjected to spoilage problems because of the mold spoilage is a serious and costly problem for bakeries. To overcome this issue, preservatives are commonly used to control mold growth in baked goods. There are two classification of preservatives which are chemical and natural. Permitted chemical mold inhibitors in bread include propionic acids and their salts. Natural food preservatives, such as cultured product, raisins and vinegar are identified by their common name on the ingredient statements. Propionates were effective in controlling mold growth on the surface of bakery products (Kumar D.P., et al., 2015). Thus, this experiment was carried out to determine the different concentration of calcium propionate on the shelf life of bread. In this experiment three condition has been set up which are control which the bread without any calcium propionate added, formulation 1 which the bread contain 200 ppm of calcium propionate and formulation 2 which the bread have a 1000 ppm of calcium propionate. The function of calcium propionate added to the bread making is acts as a preservative to help extend shelf life by interfering with the growth and reproduction of molds and other microorganisms (Raman R., 2020). Bread is the mixture of flour, water sugar, yeast and other ingredients that is mixed becoming into a dough that is baked after some time. After baking process, all formulation of breads including the control were packed in polyethene bags and left for 10 days in the humidity chamber. The observations of the breads were evaluated based on the bread sign of spoilage in terms of surface mold growth, texture changes, off-odor and overall acceptability. From the observation within 10 days, the control bread without any calcium propionate added in it was spoilage faster than the other two formulations which is they started to spoilage after 4 days. Whereas, bread with 1000 ppm was take a longer time to spoilage compared to others. From the result what we can see from the sign of spoilage on bread, the control bread without calcium propionate, have appear small amount of mold after 4 days and also started slightly off-odor on day 2. The texture change at day 3 which the bread becomes moderately hard. For overall acceptance, it was start to moderately dislike on day 4. This is due to the control bread does not have preservative added which is calcium propionate thus, make the control bread become easily to spoilage and less acceptable faster. While for 200 ppm calcium propionate which is formulation 1, the mold start to growth after 4 days and also started slightly off-odor on day 2. The texture also started changes on day 2. For overall acceptance, it was start to

moderately dislike on day 5. It shows that bread with 200 ppm calcium propionate spoilage a little bit slower than control bread due to present of food preservative. Next, for 1000 ppm which is formulation 2, the small amount of mold start to growth after 5 days and also was slightly offodor on day 5. The texture change at day 5 which the bread becomes slightly hard. For overall acceptance, it was start to moderately dislike on day 5. It shows that bread with 1000 ppm calcium propionate have longer shelf life and spoilage the slowest compared to 200 ppm calcium propionate and control bread. This is because the propionic acid helps prevent the bacterial spoilage of bread that caused by certain Bacillus sp (Kumar D.P., et al., 2015). Various methods have been adopted in an attempt to prevent mold spoilage. These include addition of humectants to reduce the water activity, addition of chemical would inhibiting preservatives such as propionates or sorbates and limiting the availability of oxygen via modified atmosphere packaging. The chemical preservative such as propionate are most affective at low pH thus acids are often added in combination with these preservative to reduce the pH of the baked product such as bread and hence improve the effectiveness of the added preservative (Williams et al., 2005). To extend the shelf life of bread, calcium propionate up to the level about 1000 ppm was added. Owing to the lower water activity of bread, the main spoilage agent are molds (Belz M.C.E., et al., 2012). According to Williams et al., (2005) bake products with a relatively neutral pH, high moisture content and high water activity such as bread and particularly prone to rapid spoilage from a variety of mold, principally Penicillium and Aspergillus species. Calcium propionate are the preferred microbial inhibitors. The microbial inhibitor may be included in a dough and/or applied to the exterior surfaces of the bread before baking.

CONCLUSION In a conclusion, the spoilage of bread was depends on concentration of calcium propionate added on it. The more concentrate calcium propionate, the harder the bread to spoilage. The result shows that bread in formulation 2 with 1000 ppm of calcium propionate takes longer time to spoilage compared to the control bread without chemical preservative hence have the longest shelf life. The mold would still grow on the surface of the bread as the calcium

propionate is just preventing or reducing the growth of the microbes. Hence, the objective was achieved. REFERENCES D. Prem Kumar, M. Jayanthi, P. Saranraj and S. Kavi Karunya. (2015). Effect of Calcium Propionate on the Inhibition of Fungal Growth in Bakery Products. Indo – Asian Journal of Multidisciplinary Research (IAJMR). Vol 1; Issue 3; pp 2 73 – 279. Retrieved from https://www.researchgate.net/publication/283122288_EFFECT_OF_CALCIUM_PROPIONATE _ON_THE_INHIBITION_OF_FUNGAL_GROWTH_IN_BAKERY_PRODUCTS Food Act 1983 & Regulations. (2017). International Law Book Services. Retrieved from http://fsis2.moh.gov.my/fosimtestsite/HOM/frmHOMFARSec.aspx?id=21 Graham Williams, Joss Delves-Broughton, John Faragher, and Diane Salmela. (2005). Baked Product with Increased Shelf Life and Process for Increasing the Shelf Life of Baked Products.

Patent

Application

Publication.

Retrieved

from

https://patentimages.storage.googleapis.com/61/b8/fb/4b09a3074bb69b/US20050163895A1.pdf James

P.S.

(2017).

Calcium

Propionate.

Retrieved

from

https://science.jrank.org/pages/1123/Calcium-Propionate.html Markus C E Belz, Regina Mairinger, Emanuele Zannini, Liam A M Ryan, Kevin D Cashman and Elke K Arendt. (2012). The Effect of Sourdough and Calcium Propionate on the Microbial Shelf-Life of Salt Reduced Bread. Appl Microbiol Biotechnol. Retrieved from https://pubmed.ncbi.nlm.nih.gov/22569634/ Ryan Raman. (2020). What Is Calcium Propionate, and Is It Safe? Healthline. Retrieved from https://www.healthline.com/nutrition/calcium-propionate...