The influence of electron beam radiation in the nutritional value, chemical composition and bioactivities of edible flowers of Bauhinia variegata L. var. candida alba Buch.-Ham from Brazil

Novel strategies for enhancing quality stability of edible flower during processing using efficient physical fields: A review

Edible flowers are an exotic part of the human diet due to their distinct sensorial properties and health benefits. Due to consumers demand edible flowers and their products with natural freshness and high nutritional value, there is increasing research on the application of green and efficient edible flower processing technologies. This paper reviews the application of a number of physical fields including ultrasound, microwave, infrared, ultraviolet, ionizing radiation, pulse electric field, high hydrostatic pressure, and reduced pressure aiming to improve the processing and product quality of edible flowers. The mechanism of action, influencing factors, and status on application of each physical energy field are critically evaluated. In addition, the advantages and disadvantages of each of these energy fields are evaluated, and trends on their future prospects are highlighted. Future research is expected to focus on gaining greater understanding of the mechanism action of physical field-based technologies when applied to processing of edible flowers and to provide the basis for broaden the application of physical field-based technologies in industrial realm.

Gamma irradiation and ozone application as preservation methods for longer-term storage of bee pollen

Bee pollen is a healthy product with a good nutritional profile and therapeutic properties. Its high moisture content, however, promotes the growth of bacteria, molds, and yeast during storage commonly result in product degradation. Therefore, the aim of this study is to assess the effectiveness of gamma irradiation (GI) and ozone (OZ) as bee pollen preservation methods for longer storage time, as well as whether they are influenced by pollen species. To do that, GI at a dosage of 2.5, 5.0, and 7.5 kGy was applied at a rate of 0.68 kGy/h and OZ application at a concentration of 0.01, 0.02, and 0.03 g/m3 was applied for one time for 6 h, to Egyptian clover and maize bee pollen, then stored at ambient temperature for 6 months. We then determined the total phenolic content (TPC) and antioxidant activity of treated and non-treated pollen samples at 0, 3, and 6 months of storage. Total bacteria, mold, and yeast count were also evaluated at 0, 2, 4, and 6 months. Statistical analyses revealed that, TPC, antioxidant, and microbial load of both clover and maize pollen samples were significantly (p < 0.05) affected by both treatment and storage time and their interaction. Both methods were extremely effective at preserving the antioxidant properties of pollen samples after 6 months of storage at room temperature. Furthermore, the highest concentrations of both GI and OZ applications completely protected pollen samples from mold and yeast while decreasing bacterial contamination. GI at the highest dose (7.5 KGy) was found to be more effective than other GI doses and OZ application in preserving biologically active compounds and lowering the microbial count of pollen samples for 6 months. As a result, we advise beekeepers to use GI at this dose for longer-term storage.

Wild Edible Flowers of Western Himalayas: Nutritional Characterization, UHPLC-QTOF-IMS-Based Phytochemical Profiling, Antioxidant Properties, and In Vitro Bioaccessibility of Polyphenols

Four edible flowers commonly consumed in the Western Himalayan region, namely, Bauhinia variegata (Kachnar), Tropaeolum majus (Nasturtium), Matricaria chamomilla (Chamomile), and Tagetes erecta (Marigold), were characterized for their nutritional and phytochemical composition. Through the UHPLC-QTOF-IMS-based metabolomics approach, 131 compounds were tentatively identified consisting of phenolic acids, flavonoid glycosides, terpenoids, amino acids, and fatty acid derivatives. Kaempferol and quercetin glycosides for Kachnar, apigenin glycosides and caffeoylquinic acid derivatives for Chamomile, patulin and quercetin derivatives for Marigold, cyanidin and delphinidin glycosides for Nasturtium were the predicted marker metabolites identified through non-targeted metabolomics. Kachnar and Chamomile scored best in terms of macronutrients and essential micronutrients, respectively. Nasturtium contained high concentrations of α-linolenic acid, anthocyanins, and lutein. Kachnar contained the highest total phenolic acids (63.36 ± 0.38 mg GAE g-1), while Marigold contained the highest total flavonoids (118.90 ± 1.30 mg QUE g-1). Marigolds possessed excellent free radical scavenging and metal chelation activities. Chamomile exhibited strong α-glucosidase inhibition activity, followed by Nasturtium. The in vitro gastrointestinal digestibility of flower extracts indicated that the bioaccessibility of phenolic acids was higher than that of flavonoids. Polyphenols from Nasturtium and Chamomile showed the highest bioaccessibility. The study is an attempt to characterize traditionally consumed edible flowers and promote their wider utilization in gastronomy and nutraceuticals.

Analysis of Chemical Constituents of Chrysanthemum morifolium Extract and Its Effect on Postprandial Lipid Metabolism in Healthy Adults

Chrysanthemum extract possesses antioxidant potential and carbohydrate and fat digestive enzyme inhibitory in vitro. However, no evidence supporting chrysanthemum in modulation of postprandial lipemia and antioxidant status in humans presently exists. This study was to analyze the composition of Imperial Chrysanthemum (IC) extract and determine the effect on changes in postprandial glycemic and lipemic response and antioxidant status in adults after consumption of a high-fat (HF) meal. UHPLC-MS method was used to analyze the components of two kinds of IC extracts (IC-P/IC-E) and in vitro antioxidant activities were evaluated using 1,1-diphenyl-2-picrylhydraxyl (DPPH), 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and Hydroxyl radical (HR) radical scavenging assays. Following a randomized design, 37 healthy adults (age, 25.2 ± 2.6 years, and BMI, 20.9 ± 1.5 kg/m2) were assigned to two groups that consumed the HF meal, or HF meal supplemented by IC extract. Blood samples were collected at fasting state and then at 0.5, 1, 2, 4, 6 and 8 h after the meal consumption. There were 12 compounds with relative content of more than 1% of the extracts, of which amino acid and derivatives, flavonoids, carboxylic acids and derivatives were the main components. Compared with IC-E, the contents of flavonoids in IC-P increased significantly (p < 0.05), and the cynaroside content exceeded 30%. In addition, IC-P showed strong free radical scavenging activity against DPPH, ABTS and HR radicals. Furthermore, according to repeated−measures ANOVA, significant differences were observed in the maximal changes for postprandial glucose, TG, T-AOC and MDA among the two groups. Postprandial glucose has significant difference between the two groups at 1 h after meal and the level in IC group was significantly lower than that in control group. No significant differences were observed in the incremental area under the curve (iAUC) among the two groups. IC significantly improved the serum antioxidant status, as characterized by increased postprandial serum T-AOC, SOD, GSH and decreased MDA. This finding suggests that IC can be used as a natural ingredient for reducing postprandial lipemia and improving the antioxidant status after consuming a HF meal.

The use of alternative food sources to improve health and guarantee access and food intake

To feed and provide Food Security to all people in the world is a big challenge to be achieved with the 2030 Agenda. Undernutrition and obesity are to the opposite of a healthy nutritional status. Both conditions are associated with unbalanced nutrition, absence of food or excess of non-nutritive foods intake. These two nutritional conditions associated with food production are closely related to some goals highlighted by the United Nations in the 2030 Agenda to achieve sustainable world development. In this context, the search for alternative foods whose sustainable production and high nutritional quality guarantee regular access to food for the population must be encouraged. Alternative foods can contribute to Food Security in many ways as they contribute to the local economy and income generation. Popularizing and demystifying the uses of unconventional food plants, ancestral grains, flowers, meliponiculture products, and edible insects as sources of nutrients and non-nutrients is another challenge. Herein, we present an overview of alternative foods - some of them cultivated mostly in Brazil - that can be explored as sources of nutrients to fight hunger and malnutrition, improve food production and the economic growth of nations.

The Biodiversity of Edible Flowers: Discovering New Tastes and New Health Benefits

Floriculture and horticulture have always been two parallel and very distinct agronomic realities. Floriculture is concerned with meeting the ornamental needs of our urban ecosystems, while horticulture is based on meeting food requirements. These two activities have now converged toward a food chain where flowers are conceived of as a sort of "new vegetable" and one of the most promising novelties to satisfy the growing need for food innovation both in terms of an organoleptic and nutraceutical profile. This novelty has rapidly evolved, especially following the growing scientific evidence of the human health benefits of flowers used as food. The typically high pigment concentration of the corollas (especially flavonoids and carotenoids), which have evolved to chromatically attract pollinators, indicates a marked nutraceutical activity especially in terms of antioxidant power. In this review, we first attempted to explore which species are most promising and which should be avoided due to real or suspected toxicity problems. The nutraceutical virtues were therefore highlighted trying to focus attention on those "functional phytochemicals" capable of counteracting some specific human pathologies. Furthermore, the organoleptic profile of edible flowers was investigated since this is one of the least known aspects. The cropping systems suitable for their cultivation were therefore hypothesized and finally the criticalities of edible flowers were addressed in terms of shelf life and marketing opportunities.

Physicochemical, nutritional, bioactive compounds and fatty acid profiling of Pumpkin flower (Cucurbita maxima), as a potential functional food

The edible flowers and its several products gaining its importance as functional food. Pumpkin flower mainly consumed in India and Mexico but due to lack of scientific research there is a neophobia among people. The objective of the paper is to analyse the physicochemical, biochemical properties, proximate analysis, antioxidant activities, anthocyanin content and fatty acid profiling. The fresh pumpkin flower was having an average moisture content of 85% (wb) with a dimension of 90 × 51 x 22 mm (l x w x t). The (L, a*, b*) value signifies the bright yellow color having gumminess (26 g) and chewiness (4.70 mJ). In this study the nutritional properties of the pumpkin flower were also determined and significant amount of Sodium (11.5 mg/100 g), Potassium (18.2 mg/100 g), Calcium (17.6 mg/100 g), phenol (17.39 µg/ml), flavonoid (17.13 µg/ml), antioxidant (51.65%DPPH) and anthocyanin (10.3 mg/100 g) was present. Among several fatty acids’ oleic acid (21%), myristic acid (15.99%) and stearic acid (15.19%) was maximum. The presence of several phytonutrients and fatty acids makes pumpkin flower a potential source of functional food in near future.

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Edible Flowers, Old Tradition or New Gastronomic Trend: A First Look at Consumption in Portugal versus Costa Rica

This study investigated the knowledge and use of edible flowers (EF) in two countries, Portugal, in Europe, and Costa Rica, in Latin America, and aimed to evaluate the similarities and/or differences regarding the utilization of EF in gastronomy. This work consisted of a questionnaire survey, undertaken on a sample of 290 participants. The results indicate that most people surveyed (87%) have heard about EF but believe there is not enough information about them (96%). Only one third of participants consider there are risks associated with the consumption of EF, being those related to toxicity and pesticides. Significant differences (p < 0.05) were found between participants from the two countries but not with different professional areas. About half (48%) of the participants had already consumed EF, mostly for decoration or confection of dishes (77% positive answers) and in salads (75%). The flowers consumed most frequently were chamomile and rose, respectively, in Costa Rica and Portugal. Reasons pointed out to consume EF include decoration, taste, novelty and aroma, while aspects such as nutritional value or antioxidant capacity are prized by fewer consumers. EF were mostly acquired in supermarkets, cultivated at home or collected in the wild. In general, most participants (85%) consider the use of EF in gastronomy interesting, but less than one third (27%) believe we should eat EF more often. Finally, discriminant function analysis revealed that country was the variable for which the differences in the consumption of EF was more pronounced, while education level and age group showed the lowest variability between groups.