Effects of successive harvesting in the same year on quality and bioactive compounds of grapes and juices in semi-arid tropical viticulture

Phenolic composition and encapsulation of Brazilian grape seed extracts: evaluating color stabilizing capacity in grape juices

The color of grape juice is an important acceptance attribute by consumers, but it suffers losses during storage. The use of commercial antioxidants has limitations because the concept of a "100% natural drink" of Brazilian legislation. This work characterized Brazilian grape seeds, and the cultivar extract with the greatest potential was encapsulated in arabic-gum (encapsulated extract-EE) to evaluate the color stabilizing capacity. The EE used in the grape juice was compared with the commercial antioxidants sulphite and enological tannin during storage (150 days). The BRS Magna and BRS Violeta grape seeds had the highest phenolic content, and the EE showed high catechin (4108 mg/kg), epicatechin (1161 mg/kg) and procyanidin-B2 (905 mg/kg) values. Sulfite was found to be the best color stabilizer. The use of EE (0.5 g/L) in grape juice improved color stability and anthocyanin stability. It was demonstrated that encapsulated grape seed extract has color stabilizing potential and that Brazilian grape seeds are a raw material of high technological value.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-024-05956-8.

Chemical typicity of tropical tannat red wines from sub-middle São Francisco Valley, Brazil

Tannat is a Vitis vinifera cultivar with typically high phenolic compound contents, showing intense coloration, well-bodied, and great aging potential. However, even with this great potential, this variety is still commercially underexplored in the Sub-middle São Francisco Valley (SSFV). This work aimed to characterize the typicity of Tannat red wines from Sub-middle São Francisco Valley (SSFV), Brazil. In addition, the present work represents the first study featuring phenolic compounds quantification and antioxidant activity of Tannat in tropical climate wine-producing regions. Considering the condition of a short-applied maceration time during the winemaking, the tropical Tannat wine showed significant antioxidant activity and high phenolic contents. Trans-caftaric, malvidin-3-O-glucoside, and procyanidin B1 stood out among the phenolic compounds quantified, presenting Tannat with the potential to be an important grape variety to tropical wine-producing regions in Brazil, containing high contents of bioactive compounds. Previously results to compounds (-)-epigallocatechin gallate, procyanidin B2, quercetin-3-β-D-glucoside, pelargonidin-3-O-glucoside, chlorogenic acid, and piceatannol were not found in Tannat wines. Further studies are necessary to make the Tannat grape's adaptation better in tropical climate conditions, including investigating the phenolic profile and antioxidant activity of Tannat red wines with longer maceration times during the winemaking.

Graphical abstract

Incorporation of phenolic-rich ingredients from integral valorization of Isabel grape improves the nutritional, functional and sensory characteristics of probiotic goat milk yogurt

This study elaborated different probiotic goat milk yogurt formulations with addition of a low-calorie Isabel "Precoce" grape preparation and flour from derived solid by-products. Physicochemical characteristics, probiotic counts, phenolic and protein/peptide molecular weight profile, antioxidant capacity (AC) and sensory acceptance of different yogurt formulations were evaluated. Yogurts with Isabel grape ingredients (IGI) had high nutritional value, distinct phenolic profile and high AC. High counts of probiotic Lactobacillus acidophilus La-05 were found in yogurts during storage. AC of yogurts with IGI increased during a simulated gastrointestinal digestion with breakdown of high molecular weight proteins and release of protein-bound phenolics. AC of yogurts with IGI should be linked to goat milk peptides and Isabel grape phenolics. Yogurts with IGI had enhanced sensory acceptance. Incorporation of Isabel grape preparation and derived by-product flour into probiotic goat milk yogurt resulted in an added-value product with multifunctional characteristics and improved sensory characteristics.

Assessment of the Multiannual Impact of the Grape Training System on GHG Emissions in North Tajikistan

The overarching goal of agricultural sciences is to optimize production technology to rationalize the use of production resources, energy, and space. Due to its high fertilization and water requirements, the vine is a plant with a high potential for greenhouse gas (GHG) emissions. The modifying factor in the production technology is plantation management. To reach the assumed goal, a field experiment was conducted in the years 2001–2020, and the following training systems were used: multi-arm fan system (A) trunk height <30 cm, (B) 80 cm, (C) 120 cm, one-side multi-arm, paired planting (D) 120 cm, (E) 140 cm. The total amount of GHGs emitted in vine cultivation was calculated according to ISO 14040 and ISO 14044 standards. The system boundaries were: establishing the plantation, the production and use of fertilizers and pesticides, energy consumption for agricultural treatments, and gas emissions from the soil. The amount of GHG emissions for cultivation using the systems A, B, C ranged from 426.77 to 556.34 kg of CO2-eq Mg of yield−1, while in the case of D and E systems, the value was approx. 304.37 to 306.23 CO2-eq Mg of yield−1. When comparing this stage with total annual emissions related to cultivation (for 1 ha), the amount of emitted GHGs at this stage is from approx. 42% to 58% higher than from annual emission related to cultivation. Concrete poles are the main element related with GHG emission during stage of plantation establishment, from 97 to 98% of emission. In the case of annual production, nitrogen fertilizers are responsible for approx. 36%. Moreover, the results show that systems D and E increased the average annual fruit yield (per 19 years of research) by approx. 68% compared to the A, B, C systems. There was no difference in the yield of plants with different height of shoots in the D and E systems. The “one-side, multi-arm, paired planting system” was characterized by the highest production and environmental efficiency.

Brazilian varieties of acerola (Malpighia emarginata DC.) produced under tropical semi-arid conditions: Bioactive phenolic compounds, sugars, organic acids, and antioxidant capacity

Acerola fruit has gained prominence for its high nutraceutical value, associated with high levels of ascorbic acid and phenolic compounds. The objectives of this study were to analyze the chemistry composition and antioxidant capacity in seven Brazilian varieties of acerola. All acerola genotypes were harvested at the red ripe maturity stage, and the fruit were subjected to metabolite analyses by High-Performance Liquid Chromatography. The varieties presented high levels of ascorbic acid and malic acid. The main sugars observed in acerola were glucose and fructose. Cyanidin-3-rhamnoside was the main phenolic compound in the fruit (149-682 mg/kg FW), which had higher concentration in the varieties BRS 235-Apodi, BRS 236-Cereja, and BRS 237-Roxinha. Other phenolic compounds also observed in the fruit were quercetin-3-glucoside, isorhamnetin, catechin, procyanidin A2, naringenin, hesperidin, chlorogenic acid, and trans-resveratrol. In conclusion, the observed wide range of acerola nutraceutical properties was related to the high genetic variability among genotypes. PRACTICAL APPLICATIONS: Brazil is the world's largest producer, consumer and exporter of acerola, with commercial orchards distributed all over the country. According to the Brazilian Ministry of Agriculture, Livestock and Supply, about eighteen registered varieties of acerola have been produced in the country. Among them are the varieties developed by Breeding Programs at the Brazilian Agricultural Research Corporation (Embrapa). Despite the great diversity of studies about acerola composition, only a few studies have focused on analyzing specific varieties. Therefore, limited information is currently available on the profile of metabolites of commercial interest in acerola varieties, such as sugars, organic acids and some phenolics. This study showed that acerola nutraceutical properties was highly dependent on the genotype.

New trends in the use of enzymes for the recovery of polyphenols in grape byproducts

Residues from wine and juice processing still contain about 70% of the phenolic compounds in grapes. These compounds are valued for having several bioactive properties that are explored in the pharmaceutical and food sectors. This paper aims to summarize the most recent advances in the use of enzymatic techniques for the recovery of bioactive compounds from GP for industrial application. For this, we analyzed scientific articles and patent applications from the last 20 years in the main indexed and patent databases. Among the most used enzymes in the recovery of bioactive compounds in wastes, cellulases, pectinases, tannases, glucoamylases, and proteases such as trypsin and chymotrypsin, are the most important. As a result, extracts are obtained with greater retrieval of compounds such as anthocyanins, gallic acid, catechins, epicatechins, and trans-resveratrol and the improvement of coloring, anti-inflammatory, antioxidant and vasoprotective properties. Although the use of enzymes for the recovery of phenolics is an old strategy, the number of studies focusing on the functional characteristics and industrial applicability of the extracts obtained has been recently growing. PRACTICAL APPLICATIONS: Phenolic compounds have acted as anti-inflammatories, antioxidants, anticarcinogens, and antimicrobials, being additives or relevant ingredients for various products in the food and pharmaceutical industry. Although there are several techniques for extracting/recovering phenolics from grape pomace, there is still no agreement on which method is ideal. In recent years, several extractions methods have been applied in seeking optimized conditions to recover phenolics from grape residues. Among them, the use of enzymes has been gaining attention for being considered a green and promising technology. The present study aims to carry out a review that would bring a new perspective to the recovery of bioactive compounds from grape residues by enzymatic techniques, with a view to industrial purpose.

Effects of Production Region, Production Systems and Grape Type/Variety on Nutritional Quality Parameters of Table Grapes; Results from a UK Retail Survey

Grapes contain high concentrations of secondary metabolites and antioxidants that have been linked to a reduction of several chronic diseases. Here, we report results of a UK retail survey, which investigated the effect of the production region (Mediterranean vs. South Africa), grape type (white vs. red vs. black) and variety, and production system (organic vs. conventional) on antioxidant activity and concentrations of phenolic compounds in table grapes. Black grapes had ~180% total antioxidant activity (TAA), ~60% higher total phenolic content (TPC) and ~40 times higher anthocyanin concentrations (TAC) than white grapes, while red grapes had intermediate levels of TAA, TPC and TAC. The effects of season and production system and differences between varieties of the same grape type were substantially smaller. Grapes imported from Mediterranean countries in summer had a 14% higher TPC and ~20% higher TAA than grapes imported from South Africa in winter, and organic grapes had a 16% higher TPC and 22% higher TAA, but ~30% lower TAC than conventional grapes. Significant differences in TPC, TAA and/or TAC between organic and conventional grapes could only be detected for specific grape types, varieties and/or sampling years.