Aromatic and Nutritional Composition of Edible Flowers of Garden Garlic and Wild Leek

Abstract

Many of the flowers of ornamental and wild plants are edible. Flowers provide colors, flavors and textures to foods and serve as a potential source of bioactive compounds such as polyphenols, flavonoids and pigments, which exert a very high antioxidant activity. The cultivation of edible flowers is a production alternative that is on the rise. The main objective of this work has been to study the nutritional and aromatic value of garden garlic (Tulbaghia violacea) and wild leek (Allium ampeloprasum). The crops were carried out in the region of L’Horta Nord (Valencia, Spain), using organic production techniques. The proximate composition, antioxidant capacity, metal content and volatile fraction of the flowers were determined. The flowers of ornamental garlic and wild leek have been shown to be a source of fiber and even protein, with very low lipid content. There is no accumulation of heavy metals in these flowers. Organosulfur compounds are the chemical family of volatile components that predominate in these flowers, representing 98% of the volatile fraction of garden garlic flowers and 68.5% in wild leek flowers. The powerful antioxidant activity of the flowers studied and their relationship with a very significant aromatic fraction of sulfur components is well suited to the current trend of searching for natural and healthy foods with nutraceutical properties. It is recommended to continue studying the bioavailability of floral components and understand their effect on health, as well as organosulfur compounds for physiological functions.

1. Introduction

The diversity of shapes, sizes, aromas and colors of flowers are attributes that contribute to their good positioning as elements of high ornamental value, being admired by humans for their showy characteristics. There are flowers that, without having much value for ornamentation, have a high potential to be used for their active ingredients in medicine, industry and food [1].

Edible flowers have mainly contributed to improving the aesthetic appearance of food. For this purpose, flowers have been used during the preparation of some recipes, but recently, the use of edible flowers responds to the benefits of their consumption due to the set of biologically active substances, such as phenolic compounds, carotenoids, vitamins, minerals, etc. [2,3]. For this reason, they are considered functional foods, additionally contributing to an outstanding aesthetic and freshness; clearly due to their striking colors, which attract the sense of sight, while the different flavors stimulate the sense of taste.

The consumption of flowers as food is recognized in various cultures around the world as part of traditional cuisine or alternative medicine, in addition to its wide use as an ornamental item [4]. However, many species of edible flowers can be considered more than a delicacy or a garnish due to their nutritional value as a source of proteins and essential amino acids. In this scenario, flowers represent an important segment for expanding the food market due to their adequate sensorial and nutritional characteristics, as well as the presence of bioactive compounds beneficial to human health [5]. The sociocultural factors involved in the consumption of edible flowers have been the subject of several studies [6,7] with the aim of popularizing and expanding this growing productive sector and encouraging the local use of traditional flowers, which is important to preserve traditions in danger of extinction.

Edible flowers have very diverse culinary uses [8]. They can be used as garnishes for various meals and cold buffets, scrambled eggs, salads, sauces, jams, jellies, syrups, vinegar, infusions, in ice creams, sweets, as candied flowers, in wine and liqueurs, and some flowers can even be dried and used as dried herbs. Additionally, the petals are used to decorate salads, sweet dishes, fruits, ice creams, drinks, etc.

Nutritional properties, pharmacological benefits, chemical composition and preparation methods of edible species have been increasingly studied with the growing search for natural and healthy foods [9]. The development of modern and effective methods for the extraction of bioactive compounds from flowers is also contributing to the exploration of their components [10], allowing the development of functional ingredients for the food industry [11,12]. Key information such as the appropriate taxonomy and toxicological profile is still needed to stimulate the consumption of edible flowers, as well as the creation of a manual of good practices for the proper handling (cultivation, handling and preparation) of flowers for marketing.

In addition to the aesthetic contribution, exotic aroma and delicate flavor of flowers in gastronomy, their phytochemical potential and, thus, the numerous health benefits should be highlighted [13,14,15]. Recent studies have revealed that flowers also possess several nutritional properties [16] such as antimicrobial, anti-inflammatory, antiviral, antimutagenic, antitumor and hypoglycemic activities. Allium is an important genus of flowering plants and traditional wild food species. They are characterized by a specific flavor making them an excellent cooking ingredient and for their use as future food [17].

Plants belonging to the liliaceae family include a wide group of species. Tulbaghia violacea Harv. is a perennial herbaceous bulbous plant native to Africa. It is known as sweet garlic, garden garlic, ornamental garlic or wild garlic, due to the garlic-like smell produced by the sulfur compounds derived from cysteine that are released from tissues and organs, such as flowers, leaves and rhizomes [18]. Garden garlic plants grow well in different habitats. They are fast-growing plants, 40–50 cm tall, reaching 70 cm during flowering and 30–40 cm wide. Their leaves are elongated and thin, slightly fleshy, greyish green and ribbon-shaped. They grow erect or curved from the base of the plant (Figure 1a). Allium ampeloprasum L. includes both wild and horticultural varieties, characterized by different ploidy levels. The wild plant is commonly known as wild leek. It is native to the Mediterranean region where it grows in different soil conditions [19]. The plant is vigorous and can reach up to 1 m in height, with a stem of circular section and leaves arranged along the lower half of the stem, 1–2 cm wide, flat and drooping. The inflorescence (globular umbel) is spherical or hemispherical, with many flowers (about 32–360 ovoid flowers). The tepals are ovate, 4–5 mm long, and white to light pink (Figure 1b).

Edible flowers are gaining significant recognition in global cuisine. Many chefs employ flowers such as pansies and roses to add fragrance and flavor to food and drinks, or simply to make visually simple dishes more appealing [1,20]. The edible potential of some species has been thoroughly evaluated in knapweed (Centaurea cyanus L.) [21], chrysanthemum (Chrysanthemum morifolium Ramat.) [22,23], hibiscus (Hibiscus rosa-sinensis L.) [24], lavender (Lavandula pedunculata Cav.) [25], pansies (Viola × wittrockiana Gams) [26] and pink species (Rosa spp.) [27]. They are even in the flowers of horticultural species such as pumpkin (Cucurbita moschata Duchesne cv ‘Tromboncino’) [28] or onion (Allium cepa L.) [17]; however, they have not been described from wild species belonging to the genus Allium. The study of these wild species and specifically of their flowers holds significant relevance for the fields of nutrition, gastronomy and food science.

In this context, the main objective of this work is to evaluate the nutritional composition major, volatile fraction, mineral content—including heavy metals—and antiradical activity using a DPPH assay and the total polyphenolic content of flowers from two plants belonging to the liliaceae family, the garden garlic (Tulbaghia violacea Harv.) and wild leek (Allium ampeloprasum L.), under organic cultivation and Mediterranean climate conditions. This aims to present data to promote the inclusion of flowers in food, thereby establishing new sustainable cultivation alternatives.

2. Materials and Methods

2.1. Experimental Materials

Growth of both species was carried out on a plot located in Alboraia (Valencia, Spain) (latitude: 39°29′45.29″ N, length: 0°20′42.23″ W coordinates), during 2020–2021. Organic cultivation methods were carried out on the plot, which was organic-certified 12 years ago. The cultivation design was carried out using organic farming techniques to avoid the risk of the presence of phytosanitary substances, since the final objective is the production of flowers for human consumption. Fertilization consisted of the contribution of 40 tons of sheep manure per hectare every two years, applied between the months of March and April, alternating with green manure from a mixture of vetch (100 kg ha⁻¹) and oats (80 kg ha⁻¹). Irrigation was carried out using traditional methods (Arabic irrigation system), through the historical irrigation ditch systems present in Huerta of Valencia area. Four irrigations were carried out throughout the crop cycle, with a flow rate of 5000–6000 L min⁻¹. During the growth and flowering stage no, biological control treatment was carried out.

Flowers were collected during the full flowering period of plants, approximately mid-June. Garden garlic flowers were collected from the plants cultivated for this purpose, and wild leek flowers from the wild plants existing in the plot.

2.2. Experimental Methods

For the analysis, the floral axes of 15 plants were collected. The plant material was vacuum-packed and frozen until processing and analysis, except for volatile components determination, in which case fresh flowers were used. In all cases, the entire corolla of the flowers was analyzed, once separated from the peduncle and sepals.

Proximal composition in the flowers was determined using official methods [29]: first, moisture and dry matter readings were taken using the stove J.P. Selectam (Barcelona, Spain) at 70 ± 0.1 °C until a constant weight (AOAC 984.25 method) was achieved; next, proteins were determined using the Kjeldahl method (AOAC 984.13) with the Foss Tecator 2100 Kjeltec distillation unit (Hillerød, Denmark); fat was determined using a Foss Soxhlet model ST243 SoxtecTM from LabtecTM line (Hillerød, Denmark) (AOAC 983.23 method); fiber was determined by quantifying the residue that persists after two successive hydrolyses, one acidic and the other alkaline (AOAC 991.43 method); and ashes were determined via calcination in a Carbolite CWF 1100 chamber furnace at 550 °C (AOAC 923.03 method). The carbohydrate content was calculated using difference. The total energy was calculated by multiplying by 9 kcal the grams of fat, by 4 kcal the grams of protein and carbohydrates, and by 2 kcal the grams of fiber, each for 100 g of fresh flowers. The results are expressed as g·100 g⁻¹ of dry weight (dw).

The individual mineral composition in the flowers was carried out using inductively coupled plasma emission spectroscopy (ICP-EOS), from ashes dissolved and settled with concentrated HCl until a 2% HCl solution. The equipment used was Agilent ICP-EOS 710 (700 series ICP-OES), made in Mulgrave, Victoria, Australia. The wavelengths selected for each element were the following: 177.434 nm for P, 184.887 for Hg, 196.026 nm for Se, 213.857 nm for Zn, 228.802 nm for Cd, 238.204 nm for Fe, 249.678 nm for B, 257.610 nm for Mn, 267.716 nm for Cr, 281.615 nm for Mo, 285.213 nm for Mg, 317.933 nm for Ca, 324.754 nm for Cu, 405.781 nm for Pb, 589.592 nm for Na, and 769.897 nm for K. Results are expressed in mg of the mineral element per 100 g of dry flower.

Antiradical activity via DPPH assay determination in flowers was performed according to the method described by Brand-Williams et al. [30] based on the capture of the free radical DPPH. A methanolic extract was obtained by mixing 0.8 g of flowers in 5 mL methanol solution (80% v/v); it was stirred for 1 h at room temperature, using an orbital shaker (Stuart Scientific, Chelmsford Essex, UK). The DPPH solution (25 ppm in methanol 80% v/v) was prepared, mixing 3.9 mL of this solution with 0.1 mL methanolic extract. Absorbance was measured at 515 nm after 45 min of incubation with DPPH solution in the dark using a spectrophotometer (Schott UV line 9400, Essex, UK). The antioxidant Trolox was used as standard, and the results were expressed as micromoles of Trolox equivalents in each 100 g of dry weight (µmol TE·100 g⁻¹ dw).

Total polyphenols were determined according to the Folin–Ciocalteu procedure modified by Arnous et al. [31]. An aliquot (50 µL) of aqueous extract obtained by grinding the fresh flowers with distilled water in a ratio of 2:1 (solvent:flower) was mixed with 500 µL of the Folin–Ciocalteu reagent (previously diluted with water 1:10 v/v) and 500 µL of 6% (w/v) Na₂CO₃ solution. The mixture was agitated for 10 s and allowed to stand for 1 h at room temperature for color development. The absorbance at 750 nm was measured using a spectrophotometer (Jenway 6715/UV-V, Stone, Staffordshire, UK), using gallic acid as standard. The results were expressed as mg gallic acid equivalents per 100 g of dry weight (mg EAG 100 g⁻¹ dw).

2.3. Volatile Profile Analysis

The determination of the volatile fraction from flowers was carried out using gas chromatography–mass spectrometry (GC–MS), model 6890 N Network GC System, coupled directly through a Life-T-effluent connector (1:1) to a model 5973 inert Mass selective detector mass spectrophotometer (Agilent Technologies, Santa Clara, CA, USA). The determination was carried out in two phases: the first involves the isolation of volatile constituents using the head-space solid-phase microextraction (HS/SPME) technique and the second phase involves the determination and quantification of the components.

In SPME, a fiber assembly, 65 μm PDMS/DVB Stable-flex (Supelco, Bellefonte, PA, USA), was used to collect and concentrate the aroma compounds. Before the samples were loaded, the fiber was inserted into a GC injector (250 °C) and held for 1 h, according to Moreno et al. [32]. After a 40 min equilibration period at 40 °C, the fiber was inserted into the incubated vial split less mode at 250 °C for 30 s in the gas chromatograph injection port. The analytical conditions were as follows: stationary phase HP-5MS J and W silica capillary column (30 m × 0.25 mm i.d. × 0.25 μm thickness film; 5%-phenyl-95% methylpolysiloxane), helium carried gas at a constant flow of 1 μL·min⁻¹, and the transfer line maintained at 250 °C. Initial temperature (40 °C) was maintained for 1 min, Ramp 1 from 5 °C min⁻¹ up to 200 °C for 1 min⁻¹, and Ramp 2 from 15 °C min⁻¹ up to 250 °C for 3 min. The electron impact mode with an ionization energy of 70 eV (source temperature 225 °C) was used for detection via the mass spectrometer, and the acquisition was performed in scan mode (mass range m/z 35–350 amu). MSD ChemStation E.02.02.1431 (Agilent Technologies) was used to perform chromatograms and mass spectra. Fiber cleaning between samples was 5 min at 250 °C.

The identification of volatiles took place by combining two different aspects: a comparison of their mass spectra and GC retention time with commercial standards (RS, Sigma-Aldrich Co., Taufkirchen, Germany) and the matching degree in the NIST 2017 Mass Spectral library. Finally, for quantification, a total ion current chromatogram was employed to integrate the peak area of each compound [33]. The relative proportions of each compound were calculated from the peak area of the total ion current signal on the mass spectrometer. In this work, the compounds considered as identified are those whose mass spectrum shows a height matching the NIST library (>80%), or according to the available standards.

2.4. Data Analysis

Three replicates were used to obtain the mean values for nutritional, antiradical activity via a DPPH assay, total polyphenolic, minerals and volatile parameters analyzed in the composition of garden garlic and wild leek flowers. Datasets were processed using Statgraphics Plus version 5.1 (Manugistics Inc., Rockville, MD, USA) for means, standard errors and correlations. The analysis of variance (ANOVA; at a significant level of p < 0.05) was performed according to a completely randomized design. Differences between types were identified with the F-test and the Kruskal–Wallis test to determine the relationship between the various qualitative parameters.

3. Results

3.1. Nutritional Compositions, Minerals and Bioactive Components

Table 1. Nutritional, bioactive and minerals parameters of garden garlic and wild leek flowers *.

Parameter	Garden Garlic Flowers		Wild Leek Flowers
	Mean ± SD	CV (%)	Mean ± SD	CV (%)	p-Value
Nutritional value (g 100 g−1 dw)
Moisture	82.192 a ± 0.697	0.848	77.317 b ± 0.067	0.087	0.0003
Dry matter	17.808 b ± 0.697	3.913	22.683 a ± 0.067	0.297	0.0003
Ash	6.607 a ± 0.161	2.441	3.056 b ± 0.433	14.181	0.0002
Crude protein	10.915 b ± 0.476	4.366	19.280 a ± 0.703	3.646	0.0001
Fat	1.398 a ± 0.170	12.156	1.773 a ± 0.201	11.322	0.0688
Crude fiber	16.237 a ± 0.609	3.753	10.058 b± 0.804	7.990	0.0004
Carbohydrates	64.843 a ± 1.263	1.948	65.833 a ± 1.626	2.470	0.4518
Energy value (kcal 100 g−1)	348.084 b ± 1.030	0.296	376.522 a ± 3.298	0.876	0.0001
Bioactive components
Total polyphenols (mg EAG·100 g−1 dw)	1258.400 b ± 8.547	0.679	1850.320 a ± 225.664	12.196	0.0105
Antiradical activity by DPPH assay (μmol TE·100 g−1 dw)	4333.86 a ± 184.327	4.253	2407.22 b ± 194.04	8.061	0.0002
Macrominerals (mg 100 g−1 dw)
K	330.004 a ± 49.876	15.114	370.815 a ± 22.743	6.133	0.2667
P	327.733 b ± 9.135	2.787	305.904 a ± 5.725	1.871	0.0247
Ca	590.033 a ± 84.538	14.328	305.663 b ± 7.051	2.307	0.0044
Mg	157.246 a ± 23.442	14.908	156.545 a ± 3.424	2.187	0.9616
Na	53.043 a ± 7.042	13.276	25.143 b ± 4.894	19.466	0.0049
Microminerals (mg 100 g−1 dw)
Fe	32.786 a ± 5.731	17.479	3.396 b ± 0.432	12.738	0.0009
Cu	0.773 a ± 0.143	18.531	0.413 b ± 0.024	5.815	0.0127
Zn	1.952 b ± 0.346	17.741	2.895 a ± 0.035	1.226	0.0094
Mn	1.245 a ± 0.208	16.685	0.753 b ± 0.039	5.144	0.0157
B	1.853 a ± 0.319	17.224	1.542 a ± 0.041	2.673	0.1699
Cr	0.061 a ± 0.012	20.651	0.023 b ± 0.006	25.082	0.0096
Mo	0.069 a ± 0.019	27.964	0.011 b ± 0.002	19.735	0.0066
Se	0.0099	-	0.000	-	-
Heavy metals (mg 100 g−1 dw)
Cd	0.009 b ± 0.001	15.629	0.025 a ± 0.001	6.073	0.0002
Pb	0.215 a ± 0.034	15.704	0.133 b ± 0.018	13.701	0.0208
Hg	0.0030	-	0.000	-	-

* Data are expressed as mean value ± standard error (SD), coefficient of variability (CV) and probability (p-value) for each parameter analyzed (n = 3). Mean values followed by different letters indicated a significant difference between the garden garlic flower and wild leek flower (p < 0.05) according to the ANOVA.

shows the proximate nutritional compositions of the flowers of garden garlic and wild leek, and this also included the most representative macrominerals, microminerals and heavy metals, in addition to the bioactive (total polyphenols and antiradical activity via a DPPH assay) components. The results are reported as the mean of replicates, alongside the coefficients of variability (CV) of each value and p-value, which test the statistical significance of the estimated effect of both types of flowers.

T. violacea was the species with higher moisture in the flowers, which oscillated between 81.40% and 82.71%; in the case of A. ampeloprasum, its moisture ranged between 77.25% and 77.38%. On average, garden garlic flowers contain 5.93% more moisture. The dry matter content in the flowers tested ranged from 17.81 g·100 g⁻¹ (T. violacea) to 22.68 g·100 g⁻¹ (A. ampeloprasum); the values of moisture and dry matter were significantly different between the two types of flowers. The ash level was significantly (p = 0.0002) lower in flowers from wild leek. The amount of ash was high in garden garlic flowers, which oscillated between 6.46% and 6.78%.

Crude protein concentration in flowers was found to be significantly (p = 0.0001) higher in wild leek (19.280%) versus the concentration in garden garlic flowers (10.915%), such that the protein levels in wild leek flowers double those in garden garlic flowers. Fat accumulation in the flowers of the species studied was very low and its distribution was not statistically different (0.0688), with a higher concentration for the flowers of wild leek. T. violacea was the species with the highest fiber in the flowers, which oscillated between 15.772% and 16.927%; in the case of A. ampeloprasum, its fiber ranged between 9.269% and 10.876%. On average, garden garlic flowers contained 38.05% more fiber. The carbohydrate level was not significantly different (p = 0.4518). The amount of carbohydrates was slightly lower in wild garlic flowers which oscillated between 63.591% and 66.117%. Flowers of both species studied are characterized by a low energy content. Energy values ranged from 347.003 to 349.054 kcal·100 g⁻¹ dry weight for garden garlic flowers and from 374.004 to 380.256 kcal·100 g⁻¹ dry weight for wild leek flowers, with higher significant levels (p = 0.0001) for A. ampeloprasum flowers.

Coefficients of variability (CV) showed a wide range of values in the nutritional parameters. In general, garden garlic flowers had lower coefficients of variability than those shown by the parameters of wild leek flowers. In particular, A. ampeloprasum flowers had the highest variability for nutritional parameters such as ash (14.18%), fat (11.32%) and fiber (approximately 8%). The remaining parameters for these flowers were less variable, with coefficients of variability oscillating between 0.09% for moisture and 3.65% for protein. The nutritional parameters that showed the highest variability value in garden garlic flowers were fat (12.16%) and crude protein (4.37%).

A. ampeloprasum was the species with a higher content of total polyphenols in the flowers, which oscillated between 1610.24 mg EAG·100 g⁻¹ dw and 2058.09 mg EAG·100 g⁻¹ dw; in the case of T. violacea, its total polyphenols ranged between 1252.21 mg EAG·100 g⁻¹ dw and 1268.15 mg EAG·100 g⁻¹ dw. On average, wild leek flowers contain 32% more total polyphenols. The antiradical activity measured via DPPH assay content in the flowers tested ranged from 2407.22 μmol TE·100 g⁻¹ (A. ampeloprasum) to 4333.86 μmol TE·100 g⁻¹ (T. violacea), with the differences found being statistically significant (p = 0.0002). Variability of the total polyphenolic content is higher for wild leek flowers (12.20%), while the antiradical activity via a DPPH assay also shows a greater coefficient of variability for the flowers of wild leek (approximately equal to 8.06%).

Sixteen mineral elements were analyzed and classified in order of highest to lowest concentrations in macroelements (Ca, K, Mg, P and Na), microelements (Fe, Mn, Zn, Cu, B, Cr, Se and Mo) and the elements characterized as heavy metals (Cd, Hg and Pb). In garden garlic flowers, the most abundant macromineral was calcium, which ranged in these flowers between 492.43 mg 100 g⁻¹ dw and 640.25 mg 100 g⁻¹ dw. In wild leek flowers, the most abundant macromineral was potassium, which ranged in these flowers between 347.68 mg 100 g⁻¹ dw and 393.15 mg 100 g⁻¹ dw. Phosphorus and potassium concentrations in garden garlic flowers were very similar (approximately 330 mg 100 g⁻¹ dw), and for wild leek flowers, the concentrations of phosphorus and calcium were similar (305 mg 100 g⁻¹ dw). On average, the concentration of magnesium in the flowers was 0.5% minor for wild leek, while sodium was present in higher concentrations (52.5%) in garden garlic flowers. Except for K and Mg, all the differences found in the concentrations of the macrominerals in the flowers were statistically significant.

Regarding microminerals, the high concentration of iron in garden garlic flowers stood out, with 32.786 mg 100 g⁻¹ dw compared to 3.396 mg 100 g⁻¹ dw found in wild leek flowers. Zinc was the second most abundant micromineral in both types of flowers, with an average higher concentration (32.57%) in wild leek flowers. Boron was the third most abundant micromineral in both types of flowers, with similar concentrations between both flowers. Manganese is present in the flowers studied with higher concentrations: 1.245 mg 100 g⁻¹ dw for garden garlic, versus 0.753 mg 100 g⁻¹ dw for wild leek. On average, the concentration of copper in the flowers was 46.57% higher for garden garlic, while chrome was present in higher concentrations (65.57%) in garden garlic flowers. The microminerals molybdenum and selenium were found to be the lowest among the flowers studied. Molybdenum was most abundant in garden garlic flowers (0.069 mg 100 g⁻¹ dw), while selenium was not found in wild leek flowers. All the differences found in the concentrations of the microminerals in the flowers were statistically significant, except for boron where the concentrations of this element were statistically similar in the two flowers, and for selenium, where no comparison was made because no concentrations of this mineral element have been detected in the wild leek flowers.

The three heavy metals evaluated in the flowers of the species T. violacea and A. ampeloprasum were lead, cadmium and mercury. Lead was the most abundant heavy metal in both types of flowers, with higher concentrations statistically significant (p = 0.0208) for garden garlic flowers. Cadmium presents statistically higher concentrations (p = 0.0002) in wild leek flowers, while mercury was not found in wild leek flowers and no comparison has been made for this element.

The mineral concentrations with the greatest variability were molybdenum for garden garlic flowers (27.96%), chromium for wild leek flowers (25.08%) and chrome for garden garlic flowers. The rest of the parameters present variability values that range between 13 and 19.70%, except in Cu, Zn, Mn and B, for wild leek flowers where the variability coefficients are low (between 1 and 5.80%).

3.2. Volatile Profile

A total of 28 volatile compounds were found among the two types of flowers, grouped into nine chemical families with quantitative and qualitative differences.

Table 2. List of volatile organic compounds (VOC) identified in garden garlic and wild leek flowers with their retention index (RI).

Chemical Family	Volatile Compound	RI	IM *	Aroma	Flowers **		p-Value
					Garden Garlic	Wild Leek
Alcohols	(Z)-3-hexen-1-ol	857	RS	powerful, fresh, green grass	not detected	116.199 ± 45.975
	1-hexanol	868	RS	freshly cut grass	not detected	20.430 ± 9.981
Aldehydes	hexanal	800	RS	green, fresh, fatty, fruity	not detected	4.381 ± 1.726
	nonanal	1104	RS	waxy, rose	7.476 b ± 1.265	25.984 a ± 6.048	0.0133
	decanal	1206	RS	sweet, waxy	10.801 a ± 1.534	3.930 b ± 1.266	0.0081
Benzenoids	benzaldehyde	893	MS	almond	17.779 ± 5.078	not detected
	benzyl alcohol	1036	MS	green musty	3.607	traces
Carboxylic acids and esters	nonanoic acid	1273	MS	dairy products, fatty	not detected	7.016 ± 5.942
	(Z)-3-hexenyl acetate	1005	MS	green fruity, sweet	9.721 a ± 3.527	5.331 a ± 0.940	0.2750
Furans	2-pentylfuran	993	RS	fruity, green, earthy	not detected	6.890 ± 3.490
Ketones	3-pentanone	688	MS	acetone-like	not detected	10.302 ± 0.227
Monoterpenes	p-cymene	1025	MS	sweet, soft, fresh, lemon,	not detected	4.503 ± 0.692
	limonene	1030	RS	citrus, herbal, floral	6.126 b ± 1.218	83.278 a ± 27.126	0.0159
	(E)-β-ocimene	1049	RS	herbal	5.499 a ± 2.248	14.689 a ± 13.704	0.4023
	(Z)-β-ocimene	1038	RS	floral, sweet, herbal, warm	45.208 a ± 8.541	192.146 a ± 176.494	0.3048
Alkanes	tridecane	1300	MS	green	not detected	1.696
	tetradecane	1400	MS	mild, waxy	not detected	13.418 ± 3.999
Sulphur compounds	dimethyl disulfide	746	MS	garlic	184.875 ± 68.515	not detected
	allyl methyl disulfide	920	MS	pungent, garlic-like	1318.892 ± 163.894	not detected
	methyl propyl disulfide	932	MS	onion, garlic	231.565 a ± 163.894	37.246 b ± 20.600	0.0042
	dimethyl trisulfide	970	MS	cabbage	54.580 ± 7.514	not detected
	diallyl disulfide	1081	RS	garlic	2563.305 ± 649.833	not detected
	dipropyl disulfide	1107	RS	burnt onion, green onion	208.128 a ± 75.650	730.151 a ± 408.425	0.1502
	allyl methyl trisulfide	1142	MS	garlic	305.459 ± 28.413	not detected
	methyl propyl trisulfide	1150	MS	warm, herbaceous, onion	56.361 a ± 3.983	54.502 a ± 43.337	0.9547
	dipropyl trisulfide	1328	MS	garlic-like	not detected	260.442 ± 21.481
	diallyl tetrasulfide	1532	MS	garlic, onion, green, metallic	19.945 ± 2.882	not detected
	dipropyl tetrasulfide	1570	MS	pungent sulfur-like, onion	not detected	6.489 ± 2.829

* Identification method (IM): reference commercial standard (RS) and comparison of mass spectrum with NIST library (MS). ** Mean value ± standard error (SD) for each individual VOC targeted (n = 3), expressed as GC peak area (×10⁶). Mean values followed by different letters indicate a significant difference between garden garlic flowers and wild leek flowers (p < 0.05) according to the ANOVA.

shows the list of volatile compounds names, retention index (RI), identification method (RS: reference commercial standard, MS: comparison of mass spectrum with NIST library and bibliographic data), aroma and GC peak area total mean values. The ANOVA (p-value) analysis was only performed for the nine volatile compounds that showed joint concentration in the two types of flowers.

The volatile profile analysis revealed the presence of five chemical families for Tulbaghia violacea flowers and eight chemical families for Allium ampeloprasum flowers (Figure 2). The majority of volatile components detected in the two flowers belong to the chemical group of sulfur compounds, with different distribution and quantity of the individual components of this group. Components of this chemical family, such as methyl propyl disulfide, dipropyl disulfide and methyl propyl trisulfide were detected in all the flowers studied. In addition, dimethyl disulfide, allyl methyl disulfide, dimethyl trisulfide, diallyl disulfide, allyl methyl trisulfide, and diallyl tetrasulfide were found in garden garlic flowers. The total of these compounds represents 97.94% of all aromatic components present in Tulbaghia violacea flowers (Figure 2a). In addition to the three common sulfur components, dipropyl trisulfide and dipropyl tetrasulfide were also detected in wild leek flowers. These five components represent 68.47% of the total volatile fraction in Allium ampeloprasum flowers (Figure 2b).

The second group of chemical compounds present in the flowers studied were monoterpenes, due to the presence of limonene, (E)-β-ocimene and mainly (Z)-β-ocimene. In addition, p-cymene was detected in wild leek flowers. These aromatic components were present in a higher proportion in wild leek flowers (18.52%) compared to 1.13% in garden garlic flowers. Alcohols (Z)-3-hexen-1-ol and 1-hexanol were only detected in wild leek flowers, representing 8.59% of the total aromatic components of these flowers. The rest of the components were minor, with the aldehydes of wild leek flowers standing out (2.16%) due to the presence of hexanal, nonanal and decanal, and of garden garlic flowers (0.36%) only due to the presence of nonanal and decanal. The ester (Z)-3-hexenyl acetate was found in both types of flowers, whereas nonanoic acid was only detected in wild leek flowers. The total of these compounds represents 0.19% of the volatile components of garden garlic flowers and 0.66% of wild leek flowers. The compounds benzaldehyde and benzyl alcohol belonging to the chemical family of benzenoids are only detected in garden garlic flowers, representing 0.38% of the total aromatic components of these flowers.

Tridecane and tetradecane compounds belonging to the alkanes chemical family are only detected in wild leek flowers, representing 0.88% of the total aromatic components of these flowers. The compounds 3-pentanone belonging to the chemical family of ketones and 2-pentylfuran belonging to the chemical family of furans were only detected in wild leek flowers, with a presence of 0.43% and 0.28%, respectively, compared to the total of all aromatic components of these flowers.

4. Discussion

4.1. Nutritional Compositions

A quality edible flower is known as one that combines three important characteristics, such as its turgor, aroma and color [34]. These characteristics are conditioned to the cultivation technique, the time of harvest and the correct handling in the post-harvest, mainly. It is very difficult to apply correct management in the production of edible flowers, due to the lack of specific regulations on this type of production, which is why the regulations of general edible horticulture and organic production are taken [35], to guarantee that edible flowers must be free of chemical and biological contaminants, such as pesticides and pesticide residues, heavy metals or pathogenic microorganisms, among others.

The most abundant constituent of the edible flowers studied is water. Most of the fresh weight of plants and their constituents is water. Plants are made up of a large amount of water, located mainly in the protoplasm, with an average of 85–90% water; even lipid-rich organelles, such as mitochondria and chloroplasts, contain around 50% water. Flowers of the wild leek are drier than the flowers of garden garlic, which is significantly more humid. The amount of moisture present in flowers is variable and depends on the species, variety, soil conditions and the amount of irrigation water, among other factors. The higher water content in flowers may be due to the genetic conditions, since the amount of water received and appropriate management during cultivation was identical for both types of plants. The work of Rop et al. [36] provides moisture content values for flowers with dual uses, that is, edible flowers that are also ornamental. The moisture concentrations indicated by these authors range from 58.8% for begonia flowers (Begonia boliviensis) to values of 89.81% for rose (Rosa odorata) petals, 90.14% for chrysanthemums (Chrysanthemum parthenium) and 90.32% for marigolds (Tagetes patula). For flowers from botanical families closer to those studied in the present work, such as chive flowers (Allium schoenoprasum L.), the water content was 79.99% [37], with the contents being close to those detected in this work. Similar results were obtained for the flowers of Allium L. species in the Central Siberian Botanical Garden of the Siberian Branch, where the amount of moisture in the inflorescences of onions was found to vary from 77.5 to 89.3% [38]. High moisture content is associated with low dry matter content and low caloric value. That is, lower water content tends to increase the energy density of edible flowers. In particular, both types of flowers are foods with a high water content and provide a low number of calories, making them attractive from a nutritional point of view, to configure low-calorie and healthy diets. Garden garlic flowers show similar energy values to chive flowers (58 kcal per 100 g fresh weight, fw) [37], and the energy levels of wild chive flowers were according to USDA [39] data for fresh chive leaves (90 kcal per 100 g fw).

Ash is an index of the total mineral content, based on the analysis of inorganic residues remaining after complete ignition of the organic matter in flowers, and its levels in edible flowers suggest the considerable availability of these constituents, which are considered essential for the nutrition of humans. In this study, the flowers of garden garlic had 53.75% more ash than the flowers of wild leek. The values of ash content of the flowers studied are similar to those that other authors present in the case of edible flowers [40] and with the ash concentrations that Sotelo et at. [41] contribute to a collection of wild and edible flowers from Mexico. The obtained ash results of our study for the wild leek flowers agree with [37], which found 0.77% ash in the fresh chive flowers. The ash in wild garlic flowers has similar values to the ash levels of two commercially available edible flowers, the pansy (Viola wittrockiana) and snapdragon (Antirrhinum majus) [42].

Protein content is determined by the total nitrogen concentrations reached in the flowers and, therefore, by the cultivation conditions and the genetic capacity to absorb nitrogen and synthesize protein [43]. The protein concentrations of wild leek flowers double the concentrations of this nutrient present in garden garlic flowers. These protein values are higher than those indicated by other authors in ornamental edible flowers [36], and are also higher than those indicated for edible flowers of cauliflower and hibiscus [44], chive edible flowers [38] and other edible flowers [40], but they coincide with the protein concentrations (approximately 11–27%) that Sotelo et al. [41] report for edible wild flowers from Mexico and with the values that Chensom et al. [45] indicate for the flowers of Diana rosa (Lathyrus odoratus) in their study of edible flowers used in Japan, or with the levels reported in the review by Fernandes et al. [46] for broccoli flowers. The protein values of these flowers are at concentrations similar to those of foods of plant origin such as garlic and onion. Considering that the consumption of the flowers is mainly fresh, it is a protein that does not suffer degradation from thermal treatments.

The fat in the studied flowers presents very low concentrations. It is the lowest macronutrient in the flowers. This reinforces that the flowers can be adequately used in the preparation of low-calorie and healthy diets. The fat values in the wild leek flowers double the concentrations of this nutrient in the garden garlic flowers, which indicates that the wild leek flower has greater potential to transmit flavors, due to the high relationship between fat and flavor [47]. The fat values of the studied flowers coincide with those referenced for some edible flowers, such as agave (Agave salmiana) and taro (Colocasia esculenta) [40] and with the fat concentrations that Sotelo et al. [41] provide in wild and edible flowers from Mexico. Compared with the reported values (3.45 g 100 g⁻¹ dw) for the fat content of edible chive flowers [37], garden garlic and wild leek flowers have lower concentrations of fat.

Fiber present in the edible part of the flowers includes polysaccharides, oligosaccharides, lignin, resistant starch, inulin and substances of hydrocarbon chemical nature. Fiber is one of the most interesting nutrients in edible Allium flowers. Jakubczyk et al. [48] conclude that edible flowers belonging to the Asteraceae family contain fiber levels that can be classified as a rich source of fiber, fulfilling a prebiotic function for intestinal bacteria. The fiber values of the present study are higher than those reported for chives flowers [37]. Carbohydrates are the most abundant macronutrient in edible flowers, reaching up to 90% of the dry weight [46,49]. Carbohydrates are mainly concentrated in the nectar, being an important source of soluble sugars [50].

4.2. Bioactive Components and Minerals

The antiradical activity measured via a DPPH assay is a preliminary test to study the antioxidant effect of plants. The values of antiradical activity found in the consulted literature [51] show variability between the values of this parameter in edible flowers. The values of antiradical activity in the studied flowers are within the ranges of variability published [45,52]. Throughout history, edible flowers have been used primarily for their scent and visual appeal, but increasingly, the capacity of flowers as foods that are innovative natural sources of bioactive compounds is being discovered [25,53,54,55]. For this reason, edible flowers could be considered functional foods, with nutraceutical capacity. The polyphenol levels found in Allium flowers in this study are like those reported in the consulted literature [44] where the contents can vary between 100.87 mg EAG 100 g⁻¹ fw for edible begonia flowers to 1362 mg EAG 100 g⁻¹ fw for marigold flowers. Additionally, a study by Chensom et al. [45] evaluates the polyphenol content, with values ranging from 147 mg EAG 100 g⁻¹ fw for the petunia flower to 1308 mg EAG 100 g⁻¹ fw for the yellow Cosmos flowers. For camelia flowers (Camellia sinensis), other authors [56] find values of total polyphenols similar to those of the present study flowers, and are in agreement with the levels reported for chive flowers [37]. Phenolic compounds are secondary metabolites produced in plants as a reaction to internal and external signals. Internal signals respond to the genetics of the plant, its normal development, and its distribution within the plant, with flowers being one of the vegetative organs that accumulate the most polyphenolic compounds [57]. They can also be synthesized by external signals, as a response to defense mechanisms in stress situations, due to infection, wounds, lack of water, exposure to UV light, organic production conditions, etc. [58], which causes global changes in the biological value of plants. In this sense, flowering, which was the sampling period, as well as some other processes in plant production and physiology, represent a stress for the plant and a greater accumulation of total polyphenolic compounds.

Polyphenols are widely distributed, providing color, flavor and bitterness to foods, contributing significantly to their organoleptic properties. They present more than 8000 known structures [59]. The high diversity existing in the flowers and the variability in pigments are responsible for this high plurality in the total polyphenolic content. Free radical scavenging by phenolic compounds is an important property underlying their diverse biological and pharmacological activities [60]. Some authors have observed positive relationships between polyphenol content and antioxidant activity, even in work carried out with flowers [56]. These positive relationships would indicate that total polyphenols are the main compounds contributing to antioxidant activity, mainly due to flavonoids. It is known that only flavonoids of a certain structure, and in particular the hydroxyl position in the molecule, determine antioxidant properties [61]. In general, these properties depend on the ability to donate hydrogen or electrons to a free radical, which requires a detailed study of the phenolic composition of Allium flowers for the complete evaluation of individual compounds exhibiting antioxidant activity. Furthermore, the redox properties of polyphenolic compounds, especially flavonoids, play an important role in the absorption and neutralization of free radicals [60].

On the other hand, different antioxidants respond differently to measurement methods involving specific reaction conditions and mechanisms of action. A specific polyphenolic compound, or an association of them, may have different actions as antioxidants against various free radicals. The determination of total polyphenol content via the Folin–Ciocalteu method used in this study is basically based on an electron transfer reaction, which partly explains the correlation generally found between total phenolic content and antiradical activity, but does not provide a complete idea of the nature of phenolic components in the extracts [62]. These theories could explain why antioxidant activity is not strictly positively correlated with the amounts of phenolic compounds (Figure 3), possibly because in addition to polyphenols, there may be other effective chelating agents, which can also contribute to antioxidant activity.

The content of mineral elements is one of the interesting aspects that can be considered to include edible flowers in human nutrition [36]. Each of the mineral elements fulfils a vital function in the flowers, also playing a crucial role in the formation of secondary metabolites [63], which are responsible for the pharmacological effects of the plant.

Lara-Cortes et al. [3] in a study of the composition of dahlia flowers with different petal colors, indicates that calcium and potassium are the majority elements, and the composition is higher when the petal color is orange and pink. In the available literature, several authors show values of the mineral composition of edible flowers [36,51,64,65]. Few works show concentrations related to the flowers of aromatic plants, such as calendula, lavender, echinacea or chamomile [66,67,68,69]. Some works even provide data on the mineral composition of edible flowers from legume plants [70] and from apple flowers [53].

According to Rop et al. [36], phosphorus is the second most important mineral element in edible flowers. Grzeszczuk et al. [71] indicate that the average potassium content in different flowers of ornamental plants is 300.3 mg per 100 g of dry flowers, values slightly similar to those found in this study. These authors report a high variability in potassium concentrations, thus, the flowers of Paeonia officinalis L. concentrate less of this element than the flowers of the Allium species studied. The different contributions of potassium as a fertilizer and the composition of the soil are the factors that mainly influence these differences. In general, the results of macrominerals in the studied flowers are in line with a previous study which indicated that those five elements were the most abundant in a high matrix of aromatic and ornamental species of edible flowers [36,72].

Studies on the mineral composition of flowers [36,72] indicate that the iron contents for various edible flowers range between 0.60 and 2.00 mg 100 g⁻¹ of fresh flower, while Grzeszczuk et al. [71] report average concentrations of 15.49 mg Fe per 100 g of dry flower. The results of Bulduk [70] on broad bean flowers report iron concentrations of 5.59 mg per 100 g of fresh flower. Iron concentrations in the present study can be considered high and position these edible flowers as a source of iron, especially for garden garlic flowers. The recommended nutritional intake (RNI) for iron varies according to age and gender, and on average it can be set at 14 mg. This amount of iron could be reached by consuming flowers, in this sense, 100 g of garden garlic flowers provide 41.5% of the RNI, and considering that it is mainly consumed unprocessed, the bioavailability of these elements would be very high. The rest of the microminerals evaluated in the flowers of garden garlic and wild leek show concentrations similar to those reported in the literature [70,71,72], with some exceptions of variability in relation to the concentration, for example in manganese, or due to the inability to contrast the data, for example in boron. In the case of heavy metals, the discussion is similar; the concentrations are low and similar to those detected for some elements by other authors [70]. The concentrations of these heavy metals are very low and do not cause health problems.

Figure 4 shows the comparison of six mineral elements (phosphorus and potassium: Figure 4a; calcium and magnesium: Figure 4b; zinc and iron: Figure 4c) between the contents obtained for garden garlic flowers (1), wild leek flowers (2) and four common foods, lettuce (3), leek (4), garlic (5) and apple (6). Garlic and leek have been selected for their proximity to the flowers studied, and lettuce and apple for being two highly consumed foods. The reference concentrations have been taken from the Spanish food composition database [73]. For the same amount of food, garden garlic flowers contain about four times less potassium than lettuce and leeks, almost eight times less than garlic, and almost half as much as apples. Wild leek flowers contain about three times less potassium than lettuce and leeks, almost five times less than garlic, and almost one serving less than apples. For the same amount of food, garden garlic and wild leek flowers contain about two times more phosphorus than lettuce and leeks, almost two times less than garlic, and seven times more than apples.

For the same amount of food, garden garlic flowers contain about three times more calcium than lettuce and leeks, almost six times more than garlic, and almost seventeen times more calcium than apples. Wild leek flowers contain about two times more calcium than lettuce and leeks, almost four times more than garlic, and almost eleven servings more than apples. For the same amount of food, garden garlic flowers contain about three times more magnesium than lettuce and two and a half times more than leeks, almost the same content as garlic, and five and a half times more than apples. Wild leek flowers contain about four times more magnesium than lettuce and three times more than leeks, almost one and a half times more than garlic, and almost seven times more than apples. For the same amount of food, garden garlic flowers contain about six times more iron than lettuce and leeks, almost five times more than garlic, and fourteen times more than apples. Wild leek flowers contain about the same iron content as garlic, leeks and lettuce, and almost two times more than apples. For the same amount of food, garden garlic flowers contain about one and a half more zinc than lettuce and leeks, almost three times less than garlic, and three times more than apples. Wild leek flowers contain about three times more zinc content than lettuce and leeks, two times less than garlic, and almost seven times more than apples. All this confirms that, except for potassium, the flowers of Tulbaghia violacea and Allium ampeloprasum can be considered foods with a high mineral density [36].

4.3. Volatile Fraction

Of the aromatic components, alcohols have only been detected in wild leek flowers. The alcohol (Z)-3-hexen-1-ol, known as leaf alcohol, is characterized by an intense smell of grass and freshly cut green leaves. It is produced in small quantities by most plants and acts as an attractant for many predatory insects. 1-hexanol is also characterized by the smell of freshly cut grass. These alcohols have been found in the aromas of edible carnation flowers [74], mallow [75] and camellia [76], but there are no references to their presence in the studies consulted on the aromas of Allium flowers.

Aldehydes are a major chemical family in other types of flowers [77]. In the aromas of the Allium flowers studied, aldehydes are a minor fraction and represented by hexanal (only for wild leek flowers), nonanal and decanal. Hexanal has fresh notes and is reminiscent of fruits (sweet green apple and citrus) and freshly cut grass. This component has been detected in camellia oils [76], in edible marigold flowers [78] and in flowers of the Allium genus, specifically in the flowers of A. tenuissimum [79,80]. Nonanal is a saturated fatty aldehyde that formally arises from the reduction of the carboxylic group of nonanoic acid. It is an aromatic component that recalls the fresh smell of floral compositions such as rose and jasmine. The flavor is reminiscent of citrus peel and green floral notes. In the consulted literature, it has been detected in camellia oils [76], in edible carnation flowers [74], sage [81], marigolds, cosmos and pansies [78]. Zhang et al. [79] also indicate the presence of this aromatic component in four wild onion flowers (A. tenuissimum L.) from different locations.

Of the family of benzenoids detected only in the flowers of garden garlic, benzaldehyde has been the major component. This substance is found in some nuts, such as bitter almonds, and is responsible for the characteristic taste and smell of these fruits. This component has been detected in edible carnation flowers [74] and in a type of Johnny Jump pansy flowers [78]. Zhang et al. [79] found this component in the characterization of the volatile components of Allium tenuissimum L. Furthermore, the benzyl alcohol that has been detected slightly in garden garlic flowers is remarkable because it gives the flower a pleasant smell and is found as part of the aromas of many fruits and roses [78].

Nonanoic acid or pelargonic acid is the only fatty acid detected and only in wild leek flowers. This organic acid produces oily, rancid and unpleasant aromas. These are components that can appear in the rancidity of essential oils in plants, but they are not usually common in fresh flowers. In the specific case of wild leek flowers, the concentrations found are low. The esterified component detected in both flowers is (Z)-3-hexenyl acetate, which has a fruity, sweet, green, banana-and pear-like aromatic description, adding natural freshness to delicate flowers, such as daffodils [82]. These components have been found as part of the aroma of fruits and in jasmine flowers [83] and roses [84].

2-Pentylfuran, detected only in wild leek flowers, is a volatile heterocyclic compound formed by the auto-oxidation of linolenic acid and is mainly associated with the flavor of soybean oil, which has fruity and green aromas. Some authors [76] have found it in the essential oils of camellia species and it shows antioxidant and antibacterial activity. Zhang et al. [79] have also found it in four wild onion flowers (A. tenuissimum L.).

3-Pentanone has only been found in a small amount in wild leek flowers. This ketone component has been found in aloe vera flowers [85]. In the work of Zhang et al. [80] on aromatic components of wild onion flowers (A. tenuissimum L.), the presence of other ketone components different from those detected in this study is reported.

The monoterpene family has been identified by four components, although p-cymene only in wild leek flowers. In general, these monoterpene compounds are characterized by a pleasant sweet and herbal smell, and menthol and citrus aromas. They are compounds with anti-inflammatory action [86] and have been found in many edible flowers [50,75,81], in particular, the isomers of β-ocimene act as a defense for plants thanks, in part, to their antifungal activity.

Alkanes detected in the wild leek flower were tridecane and tetradecane. Both are saturated single-chain hydrocarbons. These compounds have a role as a plant metabolite and are aromatically an oily component. They have been reported in greater or lesser concentrations in some edible flowers [81]. Ivanova et al. [87] detected the two alkanes in the flowers of A. ursinum, while Zhang et al. [79] found tridecane in two of the flowers of wild onion (A. tenuissimum L.).

Sulfur components, mainly sulfides, disulfides, trisulfides and tetrasulfides, with methyl, propyl or allyl radicals are found in the highest concentration in garden garlic flowers. In general, these are molecules with low molecular weight, that are very volatile and mainly contribute to the pungent and acrid taste and smell of the edible parts of lily species, some of them presenting allergenic properties. These compounds have been linked to different beneficial and protective effects on the body, mainly due to antimicrobial, antithrombotic, antitumor, antiarthritic and hypoglycemic activity [88,89], due to the allylic derivatives that inhibit the effects of these diseases. Ivanova et al. [87] detected sixteen organosulfur components in the flowers of A. ursinum, while Zhang et al. [79] found twelve components in the flowers of wild onion (A. tenuissimum L.).

The higher fraction of sulfur compounds in garden garlic flowers makes them attractive substitutes for garlic in culinary preparations, to soften the final flavors. Wild leek flowers provide a higher and more diverse aromatic fraction, incorporating aromas of herbs and fruits, which makes them more versatile in their uses.

5. Conclusions

Demand and consumption of edible flowers worldwide are booming, due to their use in avant-garde gastronomy that offers new experiences and increases added value to the final products. Due to their nutritional composition and organoleptic attributes, garden garlic and wild leek flowers can be an interesting high-value ingredient for the development of culinary recipes, through the formulation of healthy, nutritionally balanced recipes with attractive aromas. Flowers are mainly consumed raw, so as there is no transformation occurring from cooking or other preparations, it can be guaranteed that the high mineral density they present is maintained in the food, without suffering losses.

The cultivation of Tulbaghia violacea and Allium ampeloprasum to produce edible flowers could be incorporated into small organic cultivation plots, as perimeter lines that do not interfere with the main crop, but whose harvesting guarantees a higher income for farmers.

Future studies should focus on evaluating improvements in pre- and post-harvest handling to reduce losses, as well as on raising consumer awareness of the nutritional properties of these floral foods, as well as optimizing cultivation conditions that lead to the highest production of high-quality flowers.