Influence of vacuum packaging and long term storage on quality of whole chilli (Capsicum annuum L.)

Effects of different hot-air drying methods on the dynamic changes in color, nutrient and aroma quality of three chili pepper (Capsicum annuum L.) varieties

The effects of constant and variable temperature hot-air drying methods on drying time, colors, nutrients, and volatile compounds of three chili pepper varieties were investigated in this study. Overall, the variable temperature drying could facilitate the removal of water, preserve surface color, and reduce the loss of total sugar, total acid, fat and capsaicin contents. Electronic-nose (E-nose) and gas chromatography-ion mobility spectroscopy (GC-IMS) analyses found that aldehydes, ketones, alcohols and esters contributed to the aroma of chili peppers. The drying process led to an increase in acids, furans and sulfides contents, while decreasing alcohols, esters and olefins levels. In addition, the three chili pepper varieties displayed distinct physical characteristics, drying times, chromatic values, nutrients levels and volatile profiles during dehydration. This study suggests variable temperature drying is a practical approach to reduce drying time, save costs, and maintain the commercial appeal of chili peppers.

Post-harvest profile, processing and value addition of dried red chillies (Capsicum annum L.)

Chilli has dominated and retained an important place amongst the spices worldwide. They are dried ripe fruits intuitively consumed as a spice, condiment, culinary, and medicinal purposes. The global consumption pattern is intriguing because of the inherent pungency, aroma, taste, spicy flavour, and therapeutic properties. Predominantly, the colour and pungency decide the quality features and are actively responsible for organized marketing and trade of the dried chillies. India is one of the leading producers and exporters of chilli. The chemical composition of the chillies varies substantially with agro-climatic zones and post-harvest management strategies. The quantum of post-harvest loss of 25-35% hampers the farmer's income and affects the wholesale/retail marketing. This review paper is intended to provide a deep insight into the advancements in various post-harvest unit operations of dried red chillies. A detailed overview of post-harvest operations (drying, grading, destalking, packaging, storage) and processing techniques for value-added products (chilli powder, dried flakes, seeds, oleoresin) is discussed in this paper. The presented information will help the researchers and the industry personnel engaged in the post-harvest processing and value addition of dried red chillies.

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Destalking of dry red chillies (Capsicum annum L.) and its characterization

Abstract

The prevalent manual destalking of dried red chillies is a labour-intensive, tedious, and unhealthy practice that can cause severe health ailments to the labourers. This study focuses on the design and fabrication of a mechanized system for removing stalks from dried chillies to reduce the drudgery involved in manual operation. The machine's primary components including hopper, rotating cylinder, triangular bridges, cutting blades, destalked chilli outlet, and stalk outlet were fabricated based on the design considerations and ease of operation. The machine was evaluated considering the independent parameters viz. feed rate, cylinder speed, and cylinder inclination for optimization of its performance using one-factor-at-a-time statistical design. Physical properties of chillies, destalking efficiency of the machine, and the effect of destalking on powder characteristics were determined. Optimal performance of the machine was achieved with the chillies having 8-10% (moisture), 6.5 kg/h (feed rate), 20 rpm (cylinder's speed), and 3° (cylinder's inclination) with destalking efficiency of 85-87%. The evaluation of powder characteristics also revealed the prominence of destalking with enhanced colour attributes. The developed machine is compact, efficient, economical, requires less labour and thereby it may encourage its adoption at the farmer's level and strengthening of the value chain of dried chillies.

Graphical abstract

The Vacuum and Light-Avoided Packaging Ameliorate the Decline in Quality of Whole Chili during Storage

Vacuum packaging is a superior procedure that could maintain the quality of dried red peppers for a relatively longer period, while the effect of light avoidance was inconsistent. Therefore, this study was to evaluate the effect of vacuum in combination with light avoidance on the storage quality of peppers and to investigate vacuum packaging and vacuum and light-avoided packaging influence the quality characteristics of dried chili peppers during storage. The results indicated that the quality characteristics of peppers gradually deteriorated: redness, extractable color, capsanthin, capsaicinoids, pungency, total phenolic content, and antioxidant capacity decreased, whereas moisture, water activity, and browning index increased as storage progressed. Vacuum packaging inhibited these changes compared with the control. Vacuum and light-avoided packaging further decelerated the quality loss of dried peppers, with the minimum changes in color, pungency, and antioxidant capacity of dried peppers during storage, and these could be due to lower water activity by light avoidance. Therefore, light avoidance may be necessary to further delay the deterioration of dried peppers under vacuum, and vacuum and light-avoided packaging could better retain the quality of dried chili peppers.