Nathália Ramos de Melo

Assessment of the efficiency of essential oils in the preservation of postharvest papaya in an antimicrobial packaging system

Summary Rot and damage caused by post-harvest phytopathogenic fungi affect fruit quality. Essential oils (EO) are considered as an alternative to fungicides. Postharvest diseases of fruits may also be controlled by the bagging approach and the use of antimicrobial packaging. Based on the beneficial properties of EO and the concepts of bagging and antimicrobial packaging, this study aimed to develop sachets containing EO to be used as part of an antimicrobial packaging system. The activities of oregano, cinnamon and lemon grass EO were evaluated testing the sachets in vitro against the phytopathogenic fungi Alternaria alternata, Fusarium semitectum, Lasiodiplodia theobromae and Rhizopus stolonifer. The effects of the sachets on the microbiological and physicochemical parameters of post-harvest papaya were also evaluated. Both pure and sachet-incorporated EO showed antifungal activity in vitro against all tested fungi. For papaya, sachets containing cinnamon, oregano and lemon grass showed a significant reduction in the growth of mesophilic aerobic bacteria, yeasts and mould, with the cinnamon sachet causing the greatest reduction in microorganisms at the end of the storage time. Physicochemical parameters of papaya, such as weight loss, colour, firmness, total soluble solids/titratable acidity ratio and pH were not significantly altered by the presence of EO sachets, thus not affecting the natural ripening process of the papaya.

Desenvolvimento e avaliação de filme antimicrobiano aromatizado para aplicação em massa de pastel

The food industry, trying to meet growing consumer demand, is developing active packaging to provide quality and safety for packed food. This research aimed to develop and evaluate the implementation of active flavored films in contact with pastry dough. The active films were evaluated for in vitro antimicrobial activity against Penicillium sp. The mechanical properties of the films, the sorbic acid migration, sensory and in vivo microbiological analyses were also tested. The active films showed better results for in vitro and in vivo microbiological analyses when compared with the film with the sorbic acid incorporated directly on the pastry dough. The incorporation of sorbic acid and flavor affected the mechanical properties of the active films compared to the control film. The flavor addition provided a larger migration of sorbic acid from the film to the pastry dough. Besides the pastry dough packed in the active films showed better sensory results.

Essential Oils for Food Application: Natural Substances with Established Biological Activities

Essential oils (EOs) are natural products obtained from aromatic plants. Steam distillation and hydrodistillation are the most commonly used methods for the extraction of EOs at laboratory scale. They have been widely studied due to their potential in the food industry. EO can be used in food in order to prolong the shelf-life, and additionally, they can reduce or replace synthetics additives. Their effectiveness can be confirmed in antimicrobial and antioxidant tests performed, in general, by diffusion test in agar and DPPH• assay, respectively. Volatile compounds are present in EOs, a role in their biological activities. In this line of thought, chromatography techniques can be applied to identify the main volatile compounds present in EOs. In general, EOs extend food stability during storage, inhibiting the growth of spoilage or pathogenic microorganisms and protecting against oxidation. It is important to evaluate the responsible compounds for the biological activities of EOs and determine their utilization limits, including their safety. Highly variable composition with source species, plant parts, and/or extraction methods appears to play important roles in the variability of EO biological activities. This review provides a concise and critical insight in the use of EOs with emphasis in food applications.

Sustentabilidade quanto às embalagens de alimentos no Brasil

Change of habits and increasing consumerism observed in the recent decades have widely influenced technological innovations, as well as the growth of consumer goods production, which has consequently required a crescent packaging production. Packages are used in diverse sectors, among them the food industry stand out, in which their main functions are to contribute to food conservation and selling the product. Different materials, such as plastics, metals, glass and paper, have been used in the food packaging production. Each material has different attributes that help to conserve the product: gas, aroma, light, water barrier, microorganisms and mechanical strength are the main ones. Despite the several advantages of its application, its uncontrolled use and disposal result in a large volume of solid residues and environmental impact. Concerning this situation, alternative practices, such as reuse and development of biodegradable and green polymers, have been considered in order to reduce the impacts.