#Food processing methods techniques free

Conventional cooking of vegetables generally reduces total phenolic content and antioxidant activity. The contents of antioxidant compounds such as phenolics and their biological activities in foods may be affected by certain thermal techniques (Oms-Oliu et al. Conventional heat treatment is routinely used to extend shelf life and preserve fruits and vegetables and their products (Chipurura and Muchuweti 2010). For example, thermal and nonthermal processes are usually carried out to ensure the safety of processed juice, and heat-assisted processing is generally given to ensure microbial food safety (Noranizan and Benchamaporn 2007). However, processing may also trigger side reactions that cause unwanted changes in the physicochemical, sensory, and nutritional characteristics of foods (Boekel et al.

Some of the changes induced by processing in foods are desired such as increased shelf life through microbial inactivation, increased digestibility, and improved texture, flavor, and edibility. These procedures influence the shelf life, safety, sensory, physical, and chemical properties of foods. 2000).Ī variety of procedures are used during the handling of food from raw ingredients to finished or ready-to-eat products. Aside from their direct addition to food items, antioxidants can be used to prevent degradation during food processing, transportation, and storage (Williamson et al. The addition of antioxidants to such food items as preservatives occurs in many stages of food production (Morton et al. Antioxidants are also used as preservatives in vegetables and vegetable products fruits and fruit products cereals and bakery products milk and milk products such as cheese meat, fish, and their products and spices and other dry foods such as sugars, honey, beverages, and chewing gum (Williamson et al. The use of antioxidants in food preperations is aimed at maintaining the freshness and prevent browning and rancidity, particularly in case of foods containing large quantities of fats or oils, which are most vulnerable to oxidative rancidity. Natural antioxidants play important roles in both plant physiological systems and human health improvement (Shahidi and Ho 2005).

Vitamins C, E, and A, polyphenols, lycopene, coenzyme Q10, and certain proteins are common natural antioxidants (Shahidi and Ho 2005). Natural antioxidants exist in many foods, particularly fruits and vegetables are their rich sources. The detrimental effects of conventional processing on the quality of natural antioxidants have been compared to the effects of innovative nonthermal food treatments such as gamma and ultraviolet irradiation, ultraviolet light, pulsed electric fields, and high hydrostatic pressure. Thermal processing can be detrimental to bioactive compounds while nonthermal procedures may not cause significant deterioration of important health-promoting phytochemicals and in some cases can improve their bio-activity and bio-availability. These techniques have varying effects on bioactive compounds and their activities, and the magnitude of these effects depends on process parameters such as temperature, time, and the food matrix. Most of these methods involve thermal treatments of fruits, stems, leaves, and roots. Plant-based foods rich in phenolics, vitamin C, carotenoids, and other compounds undergo a range of processing operations before they are consumed. Herein, a comprehensive and comparative review are presented about the effects of conventional (thermal and mechanical) and relatively new (non-thermal) processing methods on phytochemicals and discussed the importance of implementing the use of those methods that could be of very helpful retaining the quality of the bioactive compounds in plant-based foods.

#Food processing methods techniques free

The health-promoting characteristics of natural antioxidants include anti-inflammatory, anti-diabetic, and hepatic effects as well as free radical scavenging.

Bioactive compounds from plant sources are generally categorized as natural antioxidants with well-known health benefits.