CHEMISTRY PBL 1 Name: Thew Sean Schoen Class: 5S4 (2024) Teacher: Pn. Chan Yoke Bee Food Additives and Medicines
A) Food Additives 1. Food additives are natural or synthetic ingredients added to food to prevent damage or to improve the appearance, taste or texture. 2. The development of the industry has led to the rise of processed foods, and consequently, more additives which are both synthetic or natural. 3. Regulation of food additives is enforced by the Ministry of Health via Food Act 1983 and Food Regulation 1985. a) Types of food additives
i) Preservatives - Preservatives are added to foods to help prevent or slow spoilage due to bacteria, molds, fungi or yeast. - Preservatives slow down or prevent changes in the food's colour, flavour or texture, delay rancidity, and maintain freshness. - There are different types of natural and synthetic preservatives. Examples of said preservatives are shown below: Benzoic acid Sodium benzoate (Used in chili sauces) (Used in bread) Examples of Synthetic Preservatives Sulphur dioxide Sorbic acid (Used in dried fruits) (Used to prevent mold)
Sugaring (Usage of sugar to make jams) Commonly used for fruits such as strawberries, blueberries, etc. Pickling (Using vinegar to pickle vegetables) Used to pickle vegetables such as cucumbers, carrots, cauliflower, etc. Examples of Traditional Preservation Methods Curing (Usage of salt to preserve meat) Fish and other meats such as ham, chicken etc. are encased in salt which dries them Fermentation (Usage of microorganisms like yeast) Fermentation process is used to create foods such as wine, bread and cheese
ii) Antioxidants Antioxidants slow down the oxidation of fats in food, preventing oily or greasy food from becoming rancid. Examples of antioxidants: 1. Ascorbic acid (Vitamin C). 2. Citric acid 3. Tocopherol (Vitamin E) Ascorbic acid is used in candy not just to preserve it, but also to enhance its sour flavour. iii) Flavourings - Flavourings are food additives used to improve the taste or smell of food. - Flavourings can replace the loss of original flavours during food processing. - Replace food seasonings that are expensive or seasonal such as those only found in certain fruits. Examples of flavourings Monosodium glutamate (MSG) Stevia (sweetener)
iv) Emulsifiers Emulsifiers are food additives used to help mix two substances that typically separate when they are combined (e.g., oil and water). Examples of emulsifiers: - Monoglycerides in peanut butter - Mustard - Soy lecithin v) Stabilisers Stabilisers are additives that serve to make food more consistent and thicker, preventing components that would normally separate from doing so. Examples of stabilisers: - Different types of gums (xanthan gum, guar gum…) - Sorbitol - Pectin
vi) Thickeners Thickeners are a substance which can increase the viscosity of a liquid without substantially changing its other properties. Examples of thickeners: - Corn starch - Gelatin vii) Dyes Dyes can be used to restore or add colour to make a food look more attractive and delicious. Examples of natural dyes: - Caramel (Also provides sweetness) - Elderberry juice - Paprika Examples of synthetic dyes: Indigo carmine Allura Red AC
b) Effects of food additives on health Negative effects of preservatives Preservatives may trigger allergic reactions in individuals Stabilisers are carcinogenic and increases the risk of cancer. Emulsifiers may contribute to issues such as bloating, diarrhea, gas or IBS. Flavour enhancers may cause migraines.
B) Medicines 1. Medicines are chemicals used with the treatment or prevention of diseases, and can be classified into traditional and modern medicines. 2. Medicines are safe when consumed within correct dosages - misuse or abuse of them can be harmful. a) Ten examples of traditional medicines:
b) Three types of modern medicine: i) Psychotic drugs Treatment for psychosis, a symptom of mental illness characterised by hallucinations. Examples: Haloperidol, clozapine, chlorpromazine ii) Corticosteroids Used to provide relief to inflamed areas. Reduces swelling, redness and irritations. Examples: Betamethasone valerate, prednisolone iii) Analgesics Relieve pain in conscious state. Example: Aspirin, paracetamol, codeine
c) Side effects and the correct usage of modern medicines
d) Differences between traditional and modern medicines
C) References Raja Jamiliah binti Raja Saigon, Aishah Peong binti Abdullah, Marwan bin Yaacob @ Salleh (2020), Chemistry Form 5, Rawang, Kubu Publications. (Textbook) i) Food additives https://www.chemicalsafetyfacts.org/chemicals/preservatives/ https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/ food-additives https://www.chemicalsafetyfacts.org/chemicals/ascorbic-acid/ https://web.archive.org/web/20080720091222if_ /http://www.foodstan dards.gov.au/_srcfiles/flavourings_user_guide_0802.pdf https://www.aocs.org/stay-informed/inform-magazine/featured-articl es/emulsions-making-oil-and-water-mix-april-2014 https://www.capecrystalbrands.com/blogs/cape-crystal-brands/whatare-stabilizers-a-comprehensive-guide-to-understanding-food-stabili zers https://www.webstaurantstore.com/guide/604/types-of-food-thickeni ng-agents-for-baking.html https://medlineplus.gov/ency/article/002435.htm ii) Modern and traditional medicines https://www.euyansang.com.my/en_MY/ba-zhen-vitalizing-herbal-sou p-955616073023.html https://typeset.io/questions/what-is-the-difference-between-tradition al-medicine-and-jxlrqrjkxw https://www.healthdirect.gov.au/paracetamol https://hesperian.org/wp-content/uploads/pdf/en_wtnd_2017/en_wtn d_2017_06.pdf https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3031942/ https://www.who.int/news-room/questions-and-answers/item/traditio nal-medicine