Effect of processing on composition changes of selected spices

Area of Science:

• Nutritional Science
• Food Chemistry
• Agricultural Science

Background:

• Vitamins like alpha-tocopherol (a form of Vitamin E) and beta-carotene are crucial antioxidants found in various vegetables.
• Domestic cooking methods can alter the nutritional content of foods, affecting the bioavailability of essential micronutrients.

Purpose of the Study:

• To investigate the true retention rates of alpha-tocopherol, tocotrienols, and beta-carotene in selected vegetables.
• To evaluate the impact of diverse domestic cooking methods on these nutrient retentions.

Main Methods:

• Vegetables including crown daisy, unripe hot pepper, onion, garlic, and red pepper were subjected to boiling, baking, stir-frying, deep-frying, steaming, roasting, and microwaving.
• Fatty acid compositions were analyzed using Gas Chromatography (GC).
• Alpha-tocopherol, tocotrienols, and beta-carotene levels were quantified using High-Performance Liquid Chromatography (HPLC).

Main Results:

• True retention of alpha-tocopherol varied significantly, with deep-frying showing the highest percentages (162.48-4214.53%) and microwaving the lowest (44.67-230.13%).
• True retention of beta-carotene also showed wide ranges, with deep-frying yielding high percentages (178.22-529.16%) and steaming the lowest (50.39-240.92%).
• Tocotrienol retention data was not detailed in the provided abstract.

Conclusions:

• The cooking method profoundly influences the retention of alpha-tocopherol and beta-carotene in vegetables.
• Deep-frying appears to preserve these specific fat-soluble vitamins more effectively compared to other methods, although further research on potential negative impacts is warranted.