In addition to their household uses, they are used in virtually all categories of the food industry. Spices and herbs are used in foods to impart flavour, pungency and color. They also have antioxidant, antimicrobials, pharmaceutical and nutritional properties.
Because of their antioxidant and antimicrobial properties, spices have dual function – in addition to imparting flavor and taste, they play a major role in food preservation by delaying the spoilage of food.
Spices which have strong antimicrobial activity include all-spice, cinnamon, clove, mustard and vanilla. Among herbs the higher antimicrobial activities were found in basil, oregano, rosemary, sage and thyme.
Some spices have stronger antimicrobial activity than others. Generally, spices, herbs and their essential oils are used in food systems within the range of 0.05 – 0.1 % (500-1000 ppm).
Essential oils extracted from spices and herbs are generally recognized as containing the active antimicrobial compounds. For example:
*Allyl isothiocyanate (mustard)
*Cinnamaldehyde, Eugenol (cinnamon)
*Thymol, Eugenol (sage)
*Thymol, Cravacrol (oregano)
Antimicrobial effects of spices and herbs