HPLC-DAD-MS Determination of Colored and Colorless Phenolic Compounds in Kalecik Karasi Wines: Effect of Different Vineyard Locations

Flavor Characteristics of Ten Peanut Varieties from China

To investigate the flavor characteristics of peanuts grown in Jiangsu, China, ten local varieties were selected. The amino acids, 5'-nucleotides and volatile substances were detected, and the flavor and odor characteristics of these varieties were estimated using an electronic tongue and nose. The results showed that the fat and protein contents of ten peanut varieties changed significantly (p < 0.05), and may have been negatively correlated with those of the Taihua 6 variety-in particular, having the highest protein content and the lowest fat content. The amino acid contents of the peanuts were 20.08 g/100 g (Taihua 4)-27.18 g/100 g (Taihua 6). Taihua 6 also contained the highest bitter (10.41 g/100 g) and sweet (6.06 g/100 g) amino acids, and Taihua 10 had the highest monosodium glutamate-like amino acids (7.61 g/100 g). The content of 5'-nucleotides ranged from 0.08 mg/g (Taihua 9725) to 0.14 mg/g (Taihua 0122-601). Additionally, 5'-cytidylate monophosphate (5'-CMP) and 5'-adenosine monophosphate (5'-AMP) were the major 5'-nucleotides detected in the peanuts. A total of 42 kinds of volatile flavor compounds were detected, with both Taihua 4 and 6 showing the most (18 kinds) and the highest content being in Taihua 4 (7.46%). Both Taihua 9725 and 9922 exhibited the fewest kinds (nine kinds) of volatile components, and the lowest content was in Taihua 9725 (3.15%). Formic acid hexyl ester was the most abundant volatile substance in peanuts, and the highest level (3.63%) was detected in Taihua 7506. The electronic tongue and nose indicated that the greatest taste difference among the ten varieties of peanuts was mainly related to sourness, and Taihua 4 and Taihua 9922 had special taste characteristics. On the other hand, the greatest smell difference among the ten varieties of peanuts was mostly for methane and sulfur organic substances, and Taihua 0605-2 had a special and strong smell characteristic. In conclusion, the content and composition differences of the flavor substances of ten peanut varieties were responsible for their divergences in taste and smell. These results will provide guidelines for the further use (freshly consumed or processed) of these ten peanut varieties.

Maturity Assessment of Different Table Grape Cultivars Grown at Six Different Altitudes in Lebanon

Table grapes are harvested based on well-known maturity indices that must be monitored after fruit veraison. The aim of this study was to assess these indices across multiple locations and environmental conditions, encompassing different table grape cultivars such as Black Pearl, Crimson Seedless, Superior Seedless, and Red Globe. For this reason, grape sampling was conducted across six distinct locations characterized by varying altitudes above sea level (m asl) and environmental conditions over the ripening season. The main maturity indices, including pH, sugar content, titratable acidity, berry firmness, and other parameters were monitored over the growing season. Moreover, the quantification of total polyphenols, total anthocyanins, and antioxidant activity was determined using spectrophotometric assays at harvesting. The study has examined the effect of the vineyard's location on grape quality and its interaction with the cultivar and environment. Crimson Seedless maintained a relatively high level of acidity with altitude near harvesting. Black Pearl exhibited a notable decline in both sugar content and berry firmness as elevation increased, whereas Red Globe demonstrated contrasting outcomes. The optimal maturity of Superior Seedless was observed at an elevation of 1000 m asl. Black Pearl and Crimson Seedless exhibited better adaptability to intermediate elevations (650 and 950 m asl), while Red Globe and Superior Seedless showed better adaptability to higher elevations (1000-1150 m asl). Among the studied cultivars, Black Pearl exhibited significantly higher levels of total polyphenols and anthocyanins, while close values were noticed between red and green cultivars.

Comparative evaluation of the phenolic content and antioxidant capacity of sun-dried raisins

BACKGROUND

Raisins are one of the favorite dried fruit because of their high healthful and nutrimental values. Three white (Besni beyazi-BBR, Hatun parmagi-HPR and Sultaniye-SR) and two red (Antep karasi-AKR and Besni karasi-BKR) grape varieties were used in the present study. The aim of this study was to determine and compare the phenolic composition and antioxidant properties of Turkish raisins.

RESULTS

Four flavan-3-ols, six phenolic acids, four flavonols and 13 anthocyanins were identified and quantified in raisins. (+)-Catechin (range, 56.3-419 mg kg⁻¹) was the mosst abundant flavanol, trans-caftaric acid (range, 20.48-114 mg kg⁻¹) was the abundant dominannt phenol acid, quercetin-3-O-glucoside (range, 2.79-12.83 mg kg⁻¹) was the dominant flavonoll and malvidin-3-O-(6-O-p-coumaroyl)-glucoside (range, 16.75-22.59 mg kg⁻¹) wass the major anthocyanin in all raisins. Antioxidant capacity were 22.69-63.66, 5.07-40.47, 7.00-17.69 and 40.d 40.74-77.41 mmol Trolox kg⁻¹ as determined bby the ABTS, DPPH, FRAP and ORAC assays, respectively.

CONCLUSIONS

27 phenolic compounds from four phenolic families (i.e. flavan-3-ols, phenolic acids, flavonols and anthocyanins) have been characterised in the raisins of three white and two red grapes. The total phenolic and anthocyanins content vary widely among different raisins. Strong correlations between antioxidative capacity and phenolic content and between antioxidative capacity and flavonol content were noticed.