The Effect of Traditional and Non-Thermal Treatments on the Bioactive Compounds and Sugars Content of Red Bell Pepper

The aim of the study was an investigation of the effect of traditional and non-thermal treatment on the bioactive compounds of red bell pepper. As a thermal process, blanching in water and in steam was studied, while for non-thermal the sonication, pulsed electric field treatment and their combination were used in this experiment. The red bell peppers were evaluated based on quality attributes such as: total carotenoids content; polyphenols; vitamin C; antioxidant activity and sugars content. Vitamin C and sugar content were analyzed using liquid chromatography and other measurements were determined based on the spectrophotometric method. Results showed that the blanching in water or in steam reduced bioactive compounds concentration; whereas non-thermal treatments as pulsed electric field (PEF) applied separately or in combination with ultrasound (US + PEF) let to obtain similar or slightly lower content of bioactive compounds in comparison to untreated peppers. When sonication (US) and combined treatment as PEF + US were applied; in most cases reduction of bioactive compounds concentration occurred. This effect was probably related to the effect of relatively long (30 min) ultrasound treatment. The application of appropriate parameters of non-thermal processing is crucial for the high quality of processed material.

Application of pretreatment methods on agricultural products prior to frying: a review

Frying is one of the methods of processing foods, which imparts flavour, taste, colour and crispness in the fried foods. In spite of an increase in the demand for fried foods by consumers all over the world, the danger posed by consuming too much fat is still a challenge. Many researchers have put forward many ideas on how to reduce the oil uptake and improve the nutritional and organoleptic qualities of foods during frying. Several pretreatment techniques applied to food materials prior to frying have been investigated by researchers in a bid to reduce the oil uptake and improve the quality parameters of fried foods. Therefore, this review focuses on the various pretreatment methods and the recent novel methods like ultrasound, infrared, superheated steam drying, microwave technique and pulsed electric field applied to foods prior to frying and its effects on the qualities of fried foods. © 2017 Society of Chemical Industry.

In vitro assessment of the bioaccessibility of carotenoids from sun-dried chilli peppers

Chilli peppers have been recognized as an excellent source of antioxidants as they are rich in bioactive phytochemicals such as carotenoids which are known to exert various beneficial effects in vivo. Absorption is an important factor in the determination of the potential biological effects of carotenoids. The bioaccessibility of a food constituent such as a carotenoid represents its potential to be absorbed in humans. There is very limited information in the literature regarding the content and bioaccessibility of carotenoids from dried peppers. Therefore, the objectives of the present study were: first, to determine the carotenoid content of 20 varieties of red, orange or yellow coloured sun-dried chilli peppers belonging to either of four Capsicum species (annuum, baccatum, chinense and chacoense); and second, to quantify the carotenoid micellarization (bioaccessibility) following an in vitro digestion procedure. Red peppers had a higher carotenoid content and bioaccessibility than either the orange peppers or yellow pepper. Xanthophylls showed greater bioaccessibility than carotenes. Our findings confirm that dried chilli peppers are a good source of carotenoids.