Analytical evaluation of carotenoids, apocarotenoids, capsaicinoids, and phenolics to assess the effect of a protective treatment on chili peppers dried at different temperatures

Abstract

The most common preservation process for chili peppers is drying, which inevitably causes oxidative degradation of thermolabile molecules. The aim of this research was to evaluate the potential protective effect exerted by an active ingredient based on grape seed oil, on pepper fruits. Grapeseed oil is rich in antioxidant compounds and was applied to pepper’s surface in form of a sol–gel product, before fruit thermal treatment. In this work, chili peppers samples were preventively treated with an active solution, and controls (untreated peppers), were submitted to a drying process performed at two different temperatures: 45 and 65 °C. Analysis of capsaicinoids, carotenoids, apocarotenoids, and phenolic content was performed to evaluate possible differences between the sets of samples. Oxidative stability of oil enriched with chili pepper powder aliquots was also measured to evaluate the antioxidant power of the samples. Obtained data showed that treated samples retained a higher amount of capsaicinoids and carotenoids. Oxidative stability of pepper powder was also higher for treated samples than for controls. Furthermore, the thermal treatment performed at 45 °C caused milder modifications than the 65 °C treatment. The applied pre-drying treatment can be proposed to prevent bioactive compounds loss and to enhance product stability and shelf-life.

Enzyme-assisted extraction of anti-inflammatory compounds from habanero chili pepper (Capsicum chinense) seeds

“…Liu et al ( 29 ) reported high total phenolic content in CPSs (3.93-6.21 mg GAE/g) using methanol, ethanol, or acetone but no information about the yield was described. Grimaldi et al characterized extracts from Capsicum annum fruits dried at different temperatures (45-65°C) and showed that the TPC decreased meanwhile the temperature increased from 6.9 mg GAE/g (45°C) to 6 mg GAE/g (65°C), in concordance with our results that the TPC equally decreased with the increasing of the temperature of extraction due the oxidation of phenolic compounds ( 30 ). Regarding seeds, Leng et al showed the total phenolic content of Australian growth bell pepper seeds and demonstrated that the variety of bell pepper did not affect the phenolic contents of extracts from the seeds (0.43-0.53 mg GAE/g), in contrast with our results in this research demonstrated that the use of EAE improved significantly the TPC of CPS extracts ( 31 ).…”

Genetic Regulation, Environmental Cues, and Extraction Methods for Higher Yield of Secondary Metabolites in Capsicum

“…Natural preservatives like lemon essential oil preserved total capsaicinoids, phenolics, antioxidant activity, and carotenoids in Habanero pepper paste while thermal processing can affect the color properties . Pretreatment of pepper fruits with grapeseed oil before drying at higher temperatures can prevent oxidative loss of capsaicinoids and carotenoids and can improve shelf life . Ozone-assisted degradation of pesticides at the rate of 5.5 g h –1 did not affect capsaicin content and color in dry chilies .…”

“…192 Pretreatment of pepper fruits with grapeseed oil before drying at higher temperatures can prevent oxidative loss of capsaicinoids and carotenoids and can improve shelf life. 193 Ozone-assisted degradation of pesticides at the rate of 5.5 g h −1 did not affect capsaicin content and color in dry chilies. 194 Chlorine dioxide (30 μL L −1 ) treatment of harvested green chili peppers reduced chlorophyll degradation rate and carotenoid biosynthesis via down regulating chlorophyll breakdown genes and carotenoid pathway genes, respectively.…”