Drying temperature, endogenous antioxidants and capsaicinoids affect carotenoid stability in paprika (red pepper spice)

Abstract

The major carotenoids and carotenoid esters in Capsicum annuum L. during thermal dehydration of pepper and storage of the ground product (paprika) were examined with special focus on the role of endogenous antioxidants such as vitamins E and C and capsaicinoids, the pungent materials in hot spice red pepper. A high-performance liquid chromatographic (HPLC) method was developed to achieve excellent separation and accurate detection of different carotenoid classes including free xanthophylls, monoesters, carotenes and di-esters. The newly developed method included gradient elution on a reversed-phase column with increasing proportions of isopropanol. The results indicated that presence of capsaicinoids in pungent pepper had a favourable effect on the stability of carotenoids during thermal drying. Among various di-esters those of lutein and zeaxanthine, as well as the mono-ester of β-cryptoxanthin were more stable than those of capsorubin and capsanthin, pointing to the possible role of epoxide and carbonyl groups in the susceptibility of carotenoids. An Arrhenius plot for degradation of carotenoids, tocopherols and ascorbic acid as a function of drying temperature showed linear relationships for all components, with ascorbic acid being the most sensitive. During storage in a refrigerator for 3 months the paprika showed high degradation of all the examined carotenoids particularly in samples prepared from pods dried at high temperatures (90 and 100 • C). An exception was for β-cryptoxanthin mono-ester and violaxanthin di-esters in a non-pungent variety. The amounts of these carotenoids lost during storage were slightly affected by the change in drying temperature. Strong correlation was found between retention of colour in stored paprika and the initial content of ascorbic acid, but not with that of tocopherols or capsaicinoids.

Evaluation of carotenoid and capsaicinoid contents in powder of red chili peppers during one year of storage

“…The report by Daood et al (2006) provided a preliminary but not conclusive investigation on the interaction between capsaicinoid and carotenoids and concluded that to highlight such interactions further studies were needed.…”

“…10 composition of the molecules of interest (Cervantes-Paz et al, 2014;Daood et al, 2006;Topuz, Dincer, Ozdemir, Feng & Kushad, 2011).…”

Recovery and Isomerization of Carotenoids from Tomato Processing By-products

“…Tai and Chen [14] reported that oven drying resulted in concentration decreases of 42 % for lutein and 48 % for b-carotene when compared with freeze drying. Daood et al [24] did not report any changes in lutein when red peppers (Capsicum annuum L.) were dried at temperatures less than 50°C. Additionally, the concentrations of lutein and b-carotene extracted from spinach and kale leaf tissues decreased &70 % as the drying temperature increased from -25 to ?75°C [25].…”

Effect of drying temperature on the nutritional and antioxidant qualities of cumari peppers from Pará (Capsicum chinense Jacqui)

“…Materska and Perucka (2005), in evaluating the antioxidant activity of capsaicin and dihydrocapsaicin extracted from C. annuum L., verified by the DPPH method that the antioxidant action of capsaicin was greater than that of dihydrocapsaicin, indicating that the double bond in the lipid chain of capsaicin influenced antioxidant activity. However, Daood et al (2006) found that capsaicinoids have a different impact on the stability of carotenoids depending on maturation and processing conditions. Thus, the higher level of capsaicin in the fresh pepper justifies its higher antioxidant activity compared to peppers subjected to heat treatments.…”