Biogenic amines and stable isotopes in the quality and authenticity of honeys from Brazil

The identification of biogenic amines and some precursor amino acids and the adulteration through stable isotopes was carried out in 114 honey from different geographic regions in Brazil (states of São Paulo (SP) and Santa Catarina (SC)) as support for evaluating quality control and food safety. Serotonin was detected in all samples, while melatonin was quantified in 92.2% of honey from SP and in 94% of SC. l-Dopa, dopamine and histamine appeared at higher levels in honey from SP. Cadaverine, putrescine, spermidine and spermine, varied little according to botanical source. Three honey from the metropolitan region of SP were considered adulterated (C4_SUGARS > 7%), 92 were authentic samples (C4_SUGARS - 7 to 7%) and 19 unadulterated (C4_SUGARS less than - 7%), with isotopic values of δ¹³C_H and δ¹³C_P > 7%. The data were important for differentiating quality as a function of biogenic amines and stable isotope technique was important in detecting honey adulteration.

Tryptophan and Biogenic Amines in the Differentiation and Quality of Honey

Honey is a natural product with beneficial properties to health and has different characteristics depending on the region of production and collection, flowering, and climate. The presence of precursor amino acids of- and biogenic amines can be important in metabolomic studies of differentiation and quality of honey. We analyzed 65 honeys from 11 distinct regions of the State of Santa Catarina (Brazil) as to the profile of amino acids and biogenic amines by HPLC. The highest L-tryptophan (Trp), 5-hydroxytryptophan (5-OH-Trp), and tryptamine (Tryp) levels were detected in Cfb climate and harvested in 2019. Although we have found high content of serotonin, dopamine, and L-dopa in Cfb climate, the highest values occurred in honey produced during the summer 2018 and at altitudes above 900 m. Results indicate that the amino acids and biogenic amine levels in honeys are good indicators of origin. These data warrant further investigation on the honey as source of amino acids precursor of serotonin, melatonin, and dopamine, what can guide the choice of food as source of neurotransmitters.

Functional and Nutraceutical Compounds of Tomatoes as Affected by Agronomic Practices, Postharvest Management, and Processing Methods: A Mini Review

Tomatoes and their by-products are indisputable sources of substances with antioxidants properties. Several factors limit the production and influence the nutritional and antioxidant quality of tomato fruit. However, consumers can benefit from the effects of environmental factors, such as water and hydric stress, UV radiation, agronomic practices, among others, which lead to changes in the content of secondary metabolites in tomatoes. Molecules as phenolic compounds, carotenoids, and biogenic amines are often formed in response to environmental adversities. In this way, the consumption of tomato fruits or their by-products with higher levels of antioxidants may be important adjuvants in the prevention or reduction of diseases. In this mini-review, we will present how pre- and postharvest conditions may influence the content of some bioactive compounds in tomatoes. Furthermore, we will present how some heat processing methods may change the antioxidant content, as well as, the functional and nutritional properties of the final product.

Delaying the harvest induces bioactive compounds and maintains the quality of sweet potatoes

We have identified the best harvesting periods, related to higher bioactive compound content and post-harvest quality, for minimally processed sweet potatoes with orange pulp and cream pulp. Quality loss in minimally processed sweet potatoes occurred due to browning in cv. Mãe de Familia and ESAM1 and to whitening in cv. Paraná. Both Mãe de Família and ESAM1 presented higher peroxidase and polyphenol oxidase activities at 120 days, and cv. Paraná contained high levels of provitamin A. β-carotene was the major carotenoid (up to 99%) in orange pulp. All cultivars harvested at 150 and 180 days and minimally processed showed the best visual quality, the highest bioactive compound content, and no microbial infection. Delaying the harvest also increase the antioxidant activity in orange roots, which was associated with a high content of carotenoids and phenolic compounds, resulting in an increase in the nutritional quality of the product. PRACTICAL APPLICATIONS: Postharvest techniques can improve the visual and phytochemical quality of vegetables and extend their shelf life. The present research provides the best harvesting periods for minimally processed cream and orange sweet potato roots with higher postharvest qualities. Delaying the harvest resulted in a product with better visual quality, higher levels of bioactive compounds, which are highly beneficial to health, for example, ß-carotene, and no microbiological contamination. Our results may contribute to improvements in the current knowledge about harvesting times for sweet potato growers who aim to produce high quality, minimally processed products with a longer shelf life.

Biogenic Amines and the Antioxidant Capacity of Juice and Wine from Brazilian Hybrid Grapevines

Some biogenic amines (BAs) are used as quality markers in grape-derived products. The prolife of 9 BAs was determined in juices and wines elaborated from hybrid grapes. Low levels of histamine, tyramine and cadaverine were found. Juices elaborated from 'BRS Rúbea' showed the highest tyramine levels (1.56 mg/L), while no histamine was found in wines elaborated from 'Seleção 34' and its higher content was detected in 'BRS Carmem' (3.55 mg/L). Juices elaborated from 'BRS Violeta' showed elevated content (472.88 mg/L) of total phenolic compounds (TPC) and mono-hydrated serotonin (6.20 mg/L), and wines elaborated from 'Violeta' presented a high serotonin mono-hydrate content (23.63 mg/L) and high antioxidant activity with FRAP test (77.24 mmol FeSO₄/L). Juices elaborated from hybrid grapes 'BRS Violeta' and wines from 'BRS Violeta', 'Seleção 34' and 'Seleção 13' had high levels of bioactive compounds, emphasizing the great potential of these cultivars for winemaking.

Nutritional value and antioxidant compounds during the ripening and after domestic cooking of bananas and plantains

Genotypes of bananas and plantains have been studied for biofortification purposes, mainly due to content of resistant starch (RS) and polyphenols. This study aims to identify banana and plantain genotypes with a high content of resistant starch, phenolic compounds and minerals, and to evaluate the impact of the ripening stage and domestic thermal processing to select superior genotypes with high levels of functional compounds. In this study, it was used bunches of bananas and plantain genotypes. The phenolic compounds profiles were determined by HPLC-DAD in pulps and peels. The resistant starch and the minerals (K, Na, Zn, Cu and Fe) were evaluated in pulps and peels of unripe fruit. The results of phenolic compounds were studied in three ripening stages, and after thermal processing (ripe stage) of two genotypes, which were most promising for biofortification studies. Resistant starch and minerals were analysed in the unripe fruits. The peel biomass showed the highest values of phenolic compounds and minerals. The total starch content in the pulp varied from 42.3% ('FC06-02') to 80.6% ('Pelipita'). Plantains and cooking bananas presented the highest contents of starch and resistant starch (stage 2 - green with yellow traces). The pulps of the dessert genotypes 'Khai' and 'Ouro da Mata', and cooking genotype 'Pacha Nadam' stood out due to their minerals high contents (P, K and Fe; Zn and Fe; Ca, Mg and Zn, respectively). The dessert bananas (e.g., 'Ney Poovan') and cooking bananas (e.g., 'Tiparot') had the highest concentrations of phenolic compounds, mainly in ripe fruit (stage 5 - yellow with green). In addition, the thermal processing of Musa spp. fruit led to increasing these secondary metabolites, mainly the cooking of fruit with peel by boiling, which should be preferred in domestic preparations.

Bioactive amines changes during the ripening and thermal processes of bananas and plantains

Bioactive amines are found in food and can be relevant for the assessment of fruits shelf life and nutritional quality. The pulp and peel of 20 banana and plantain were analyzed and the bioactive amine content varied according to the genotype, ripening stage, fruit tissue and thermal processing. In most of the analyzed genotypes, tyramine, histamine, dopamine, serotonin, spermidine, and spermine were decreased during the ripening process in the pulps. By contrast, there was an increase in putrescine level. In many genotypes of plantains, the serotonin and dopamine contents in pulp decreased until stage 5 and increased at stage 7. Peels contain higher levels of serotonin, dopamine, histamine and tyramine than pulps. Additionally, thermal processing affects the content of amines present in fruit. Boiling with the peel should be preferred in domestic preparations, regardless of the genotype used.