promotes oxidation of some chemicals present naturally in apple, those chemicals turn brown. So need something to trap metal to prevent it from intreacting with food. -Citric acid: structure like a bridge, traps metal ion (chelate). Chelating agent. -EDTA (calcium disodium): effective in tying up metal. -Sodium sulphite /bisulphite: antioxidant used as additive, prevents food from going brown. Some people are allergic to sulphite and before this was realised 20 people died. It was common in salad bars. Today its rarely used. Sometimes in grapes , keeps the crunchiness. Also used in pre-cut french fries to prevent browning. Antimicrobial agent in wine. -BHA/BHT: prevent oxidation of fat. Used in cereals. Trap free radicals , free radicals promote oxidation of fat. Free radical pick up hydrogen in BHT, leave behind another free radical but its stable. -Theory: antioxidant prevent oxidation in body, make us live longer. Ice cream have carboxymethylcellulose in it, prevent formation of ice crystalls, absorb moisture. 8
NON-NUTRITIVE SWEETNERS -Concerns with sugar has brought different types of substitutes called non-nutritive sweetners. 1) Saccharin : discovered by Constantin Fahlberg (partnerini Remsen satti). Gave some sweetness as saccharose (chemical name for sugar). Fahlberg patented, establised factory to produce saccharin. John Francis Queeny produced saccharin in US in Monsanto company . 300X SWEETER THAN SUGAR, 0 CALORIES. Have a bitter after taste. Studies showed increse incidence of bladder cancer among male rats. Rats fed high liftime amounts of saccharin and whose parent had also been fed high lifetime amounts of saccharin. A human would have to drink 800 cans of diet drinks sweetened with saccharin in order to equal the amount of saccharin that caused cancer in those test animals. In Canada, saccharin is not allowed as food additive, only tabletop sweetner . In US, saccharin was allowed but had a warning label, now they can sell without a warning label. Sweet'n low contain saccharin and warning label says its hazardous. Saccharin causes cancer in male rats by a mechanism not found in humans so not really hazardous to human. -Delaney clause: any substance that has been shown to cause cancer either in human/test animal regardless of dosage, cannot be allowed on market. But saccharine was allowed because many people were using it. -Risk=hazard x exposure x sesceptibility . If exposed to very small amount of chemical that is hazardous, the risk is very small. With saccharin there is hazard but not too much risk. 2) SWEETNERS FROM NATURALLY OCURRING ALCOHOL -Sorbitol : RELATIVE SWEETNES X0.6, 2.6 CALORIES. Used in diet products , very slowly metabolized by body. Cause exploding diarrhea. -Xylitol : RELATIVE SWEETNESS X1, 2.4 CALORIES. Present in sugarless gum because it doesnt promote tooth decay . By chewing sugarless gum, increases salivation and dilute the acid that cause tooth decay. Have laxative effect in excessive use. Bacteria cannot break down xylitol as food.
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