Colour at harvest and post-harvest behaviour influence paprika and chilli spice quality

Capsicum annuum L. paprika and cayenne chilli pepper fruit were grown for red spice production and harvested at various colour stages on the same day. Fruit of each stage were allowed to change colour at room temperature with or without the addition of 100 μl 1-1 ethylene. Fruit appearance and colour development, and respiration and ethylene production were measured during the colouring period. Ethylene treatment had no effect on colour development or pungency for both cultivars, even though it easily crossed the cuticle, epidermis and flesh tissues into the fruit cavity. Green or deep green harvested fruit failed to fully colour red, while fruit that were harvested at or after the colour break stage visually completed their red colour development within 7-9 days. However, the colour intensity of spice powder was low for all fruit that had not developed a deep red colour prior to harvest. For paprika no difference between deep red fruit that were succulent or that had partially dried on the plant was found, but chilli fruit that had partially dried before harvest produced the most intense colour. American Spice Trade Association (ASTA) extractable red colour was the best measure of spice colour quality, compared to reflected lightness (L*), chroma (C*) and hue angle (h°) colour measurements. Pungency did not change between ripeness stages for chilli and was absent in paprika. Paprika and chilli fruit showed climacteric behaviour as long as they were attached to the plant, but when detached were non-climacteric. (C) 2000 Elsevier Science B.V

Effects of ethephon on fruit yield, colour and pungency of cayenne and paprika peppers

Summary. ‘PS72285’ paprika pepper and ‘Caysan SPS705’ cayenne chilli pepper (Capsicum annuum L.) were treated with ethephon [(2-chloroethyl) phosphonic acid] with the aim of synchronising maturation for once-only machine harvesting. Ethephon solutions of 0, 1000, 3000 or 5000 µL/L were applied once as foliar applications to pot-grown plants in a shadehouse at the Waite Campus, Adelaide. The effects of ethephon on red fruit yield, colour intensity, pungency, abscission and defoliation were determined. Ethephon did accelerate fruit maturation of both cultivars by increasing the percentage of red marketable fruit for chillies and decreasing the percentage of green paprika fruit. The intensity of extractable red colour in chilli fruit was increased by 16% for 1000 µL ethephon/L, while pungency improved by 46 and 48% for 1000 and 3000 µL ethephon/L respectively. However, red marketable fruit yields measured as fresh and dry weight decreased in chillies due to a large number of abscised fruit. Paprika quality and yield were unaffected. Ethephon also induced defoliation and fruit skin damage. Thus, this study found little benefit from using ethephon as a chemical ripening agent.</jats:p

Proteomic analysis during capsicum ripening reveals differential expression of ACC oxidase isoform 4 and other candidates

Capsicum (Capsicum annuum L.) is categorised as a non-climacteric fruit that exhibits limited ethylene production during ripening and the molecular mechanisms associated with this process are poorly understood. A proteomic approach was used to identify the differentially expressed proteins during various ripening stages (Green (G), Breaker Red 1 (BR1) and Light Red (LR)) and the genes associated with their synthesis. From 2D gel electrophoresis (2DGE), seven protein spots were identified as selectively present either in G or BR1 and are involved in carbon metabolism, colour and fruit development, protein synthesis and chaperones or biosynthesis of amino acids and polyamines. One candidate of interest, 1-aminocyclopropane-1-carboxylic acid (ACC) oxidase (ACO) is known to be involved in ethylene biosynthesis and was only present in BR1 and is related to the tomato ACO isoform 4 (LeACO4) and hence named CaACO4. CaACO4 RNA expression as well as total ACO protein expression in multiple stages of ripening (G, Breaker (B), BR1, Breaker Red 2 (BR2), LR and Deep Red (DR)) corresponded to the 2DGE protein spot abundance in breaker stages. Our findings highlight the involvement of the ethylene pathway in non-climacteric fruit ripening.Wan M. Aizat, Jason A. Able, James C. R. Stangoulis and Amanda J. Abl

Oleoresins from Capsicum spp.: Extraction Methods and Bioactivity

Capsicum spp. fruit is one of the most produced vegetables around the world, and it is consumed both as fresh vegetable and as a spice like a food additive for their characteristic red color and, in many cases, its pungency. In addition to its economic importance, the bioactivity of some important compounds such as capsaicinoids and carotenoids has promoted its research. The use of Capsicum oleoresins has been increased due to its advantages comparing with the traditional dry spice. These include obtaining higher quality products with the desired content of bioactive and flavored substances. The wide diversity of extraction methods including water extraction, organic solvent extraction, microwave-assisted extraction, and ultrasound assisted extraction as well as supercritical fluid extraction among others are discussed in the present review. Moreover, pretreatments such as chemical treatments, osmotic dehydration, sun and oven drying, and freeze-drying commonly used before the extraction are also presented. Due to its importance, Capsicum oleoresins produced with “green” solvents and the improvement of fractional extraction techniques that allow to obtain separately the various bioactive fractions will continue under research for further development