RESUMO
Male orchid bees collect volatile and semi-volatile compounds from the environment for storage and accumulation in specialized hind legs. Later, these compounds form a perfume blend used during courtship to lure conspecific females for mating. Male orchid bees perfume has been suggested to play an important role as a sexual signaling trait involved in pre-mating isolation of species, functioning as an indicator of male genetic quality. Eulaema nigrita Lepeletier (Apidae: Euglossini) is a common species in both forested and woody savanna (Cerrado stricto sensu) physiognomies of the Brazilian savanna biome. By identifying the chemical composition of male E. nigrita perfume, we tested for differences in the bouquet chemical profile in populations from remnants of seasonal semideciduous forest and woody savanna. In addition, we assessed the relation between perfume complexity and morphological traits associated with size and age of males. Our analysis showed a low effect of physiognomies on differences in the perfume chemical profile of sampled males. Nevertheless, we observed significant differences in the chemical profile of individuals from two seasonal semideciduous forest remnants, which suggests an environmental effect in individual bouquet. Wing wear measurements were positively related to perfume complexity, consistent with the premise that perfumes from older individuals are indicators of survival capacity in male orchid bees.
Assuntos
Perfumes , Humanos , Feminino , Abelhas , Masculino , Animais , Pradaria , Brasil , Fisiognomia , Florestas , Tamanho CorporalRESUMO
The aim of this work was to study the effect of blanching and ultrasound pretreatments on drying and quality characteristics of apple peel. Blanching was conducted in boiling water, ultrasound in a water bath, and drying in a batch tray dryer. The product obtained was ground into a flour, and assessed for color, water activity, proximate composition, sugars, and bioactive compounds. Results showed that effective moisture diffusivity increases with a decrease in product moisture content, being such dependence well described by a second order polynomial model. Average drying rate was higher and product moisture content was lower for blanched and sonicated flour, especially for the former. Such result suggests that blanching and ultrasound enhance water removal during drying of apple peel. Physical properties were significantly affected by pretreatments, being more intense red color and lower water activity obtained for sonicated flour. Nutritional and bioactive properties were also significantly affected by pretreatments, being lower sugar, higher protein, fiber, catechin and epicatechin content observed for blanched flour. Summarizing, blanching and ultrasound pretreatments improve drying of apple peel, both regarding process efficiency and product quality.
Assuntos
Malus , Farinha , Dessecação/métodos , Frutas , ÁguaRESUMO
BACKGROUND: The importance of pollination is recognized worldwide. This study investigates the influence of biotic pollination on the chemical composition of coffee (Coffea arabica L.) cultivated in the municipalities of Araguari and Monte Carmelo, in Minas Gerais state, Brazil. Twenty samples were analyzed, of which 10 were biotically pollinated (P) and 10 non-biotically pollinated (NP). Analyses of bioactive compounds, antioxidant capacity and centesimal composition of coffees were performed. RESULTS: The results revealed chemical differences between the P and NP samples, with significantly higher levels of the bioactive compounds caffeine, trigonelline, and chlorogenic acids in the P samples. The findings indicated that pollination of the coffee plants assisted germination and made the beans less susceptible to attack by external agents. CONCLUSION: The results demonstrated that pollination services are important mechanisms affecting the chemical composition of coffee beans. Considering that the compounds evaluated are precursors of volatile compounds in coffee, this directly affects the quality of the beans. © 2023 Society of Chemical Industry.
Assuntos
Antioxidantes , Coffea , Antioxidantes/química , Coffea/química , Polinização , Sementes/química , Cafeína/análiseRESUMO
BACKGROUND: Pollination enhances coffee quality at the material level, improves the symbolic attributes of coffee and promotes sustainability. The objective of this work was to quantify the composition of volatile compounds in roasted coffee produced in the presence and absence of biotic pollination, aiming at investigating the effects of pollination on the composition of volatile compounds in coffee beans. This is the first report of its kind in the literature. RESULTS: The analysis of volatile compounds in roasted coffee beans showed that pollination increased the amount of volatile compounds in the beans; there was a significant increase in the amount of the following classes of compounds: pyrazines, pyrroles, pyridines, alcohols and phenols. Considering that most volatile compounds in roasted coffee are derived from reactions involving carbohydrates, proteins, chlorogenic acids and some alkaloids, our hypothesis is that pollinated coffee beans are better prepared for germination and for defense of the crop against attack by external agents. CONCLUSION: The findings of this study point to the important role played by sustainable practices implemented in coffee cultivation. The results obtained in this study pave the way toward the conduct of further investigations, including the analysis of the chemical composition of aroma precursors and volatile compounds in raw coffee beans, and the study of the sensory aspects of roasted coffee. © 2022 Society of Chemical Industry.
Assuntos
Coffea , Coffea/química , Manipulação de Alimentos/métodos , Odorantes/análise , Polinização , Sementes/químicaRESUMO
Glyphosate is the main herbicide used in soybean crops, and Brazil is one of the major soybean producers around the world. GLY and AMPA were evaluated in 124 surface waters samples of twenty one micro basins in Paraná Basin 3 (State of Parana, Brazil) over six subsequent weeks. A simple and economical routine methodology was established, based on lyophilization as a pre-concentration method. The validated method showed a limit of detection of 0.0125 and 0.025 µg L-1 for GLY and AMPA, respectively. In general, water samples presented concentrations ranging from 0.31 to 1.65 µg L-1 for GLY. Those values are below the maximum allowed amounts in Brazilian Law (65 µg L-1). The AMPA values were found in the range from 0.50 to 1.40 µg L-1. In summary, GLY was detected in 19.3% and it was quantified in 17.7% of the samples. AMPA was detected in 21.8% and it was quantified in 1.6% of the samples. Although samples did not present values higher than the established by Brazilian Law, GLY and AMPA appear constantly in the samples, which highlight the importance of monitoring studies in watersheds.
Assuntos
Água Doce/análise , Glicina/análogos & derivados , Herbicidas/análise , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico/análise , Brasil , Cromatografia Líquida de Alta Pressão , Fluorescência , Liofilização , Glicina/análise , GlifosatoRESUMO
With globalization, it has become necessary to adopt policies to regulate the coffee market, addressing problems including the authenticity and traceability of products. It is therefore important to establish methodologies that can help to safeguard the interests of producer countries and add value to products. For this purpose, the use of NMR combined with multivariate statistical procedures can be an attractive option. The aim of this study was to develop a fast and effective technique, using 1H NMR coupled with multivariate statistics, to create a fingerprint of roasted coffees, distinguishing them according to the main Brazilian producer regions. Several compounds suitable for differentiating roasted coffees were identified in the fingerprint. Discriminant analysis revealed good distinction among the samples. The compounds catechol, trigonelline, caffeine, and n-methylpyridine were most important for the differentiation. The findings should assist coffee-producing countries in adopting measures to protect their markets and to add value to coffee products.
RESUMO
Coffee is a ubiquitous food product of considerable economic importance to the countries that produce and export it. The adulteration of roasted coffee is a strategy used to reduce costs. Conventional methods employed to identify adulteration in roasted and ground coffee involve optical and electron microscopy, which require pretreatment of samples and are time-consuming and subjective. Other analytical techniques have been studied that might be more reliable, reproducible, and widely applicable. The present review provides an overview of three analytical approaches (physical, chemical, and biological) to the identification of coffee adulteration. A total of 30 published articles are considered. It is concluded that despite the existence of a number of excellent studies in this area, there still remains a lack of a suitably sensitive and widely applicable methodology able to take into account the various different aspects of adulteration, considering coffee varieties, defective beans, and external agents.