Blanching is a short heat treatment that is typically applied to vegetables prior to further processing with aim of enhancing both safety and quality attributes. It imparts benefits such as the destruction of surface micro flora on vegetables and the enhancement of the color, texture and also the keeping quality of vegetable products.The quality of blanched products depends significantly on the time-temperature combinations of blanching and also on the vegetable type. Under-blanching speeds up the activity of enzymes.
Blanching methods may be employed such as conventional water blanching, microwave, or steam blanching; Conventional water blanching usually imparts more uniform processing. However, prolonged water blanching results in considerable losses in phytochemicals and antioxidant properties.
Steam blanching is generally carried out in steam blancher where the vegetable product is exposed directly to a food-grade steam typically at a temperature close to 100°C. Steam blanching results in minimum losses in phytochemicals and antioxidant capacity furthermore, it requires less time than conventional blanching because the heat transfer coefficient of condensing steam is greater than that of hot water and it is proven to be comparatively economical as it saves energy.
Microwave heating is three-to five- time faster than conventional heating and relies on the application dielectric heating. This is accomplished by using microwave radiation to heat water and other polarized molecules within the food, leading to heat generation in the entire volume at the same rate due to internal thermal dissipation of water molecule vibrations in the food. It has advantages over conventional heating methods such as precision timing, speed, and energy saving.
Thus, if you plan to enhance the color, taste, and freshness of vegetables, blanching will be a good choice, which is a simple cooking process. Blanching is really not a hard skill to learn and it's usually a certain choice for a cooker.