Physicochemical Properties Of Juice Research Articles

Morphological characteristics, ascorbic acid and antioxidant activity during fruit ripening of four lemon (Citrus limon (L.) Burm. F.) cultivars

Citrus limon (L.) Burm contains many important natural bioactive compounds, such as ascorbic acid, essential oils, and antioxidant substances. An experiment was carried out on four lemon cultivars (Ovale di Sorrento, Sfusato Amalfitano, Femminello Cerza and Femminello Adamo) from Southern Italy to study the changes in physico-chemical properties of juice during fruit ripening. Morphological characteristics of fruits, total soluble solids, pH and titratable acidity, ascorbic acid (AsA), and antioxidant activity (TEAC) of juice were tested.The concentrations of AsA in lemon juice showed significant differences among cultivars and ripening stages, with a steadily decrease along ripening stages: from 31.38 of stage I to 23.71 mg 100 g−1 of stage IV. The juice AsA concentration correlated with the colorimetric parameters of peel: L (r = −0.643), a (r = −0.719) and b (r = −0.654). The cv Ovale di Sorrento showed the highest average AsA concentration (29.91 mg 100 g-1). The level of the total TEAC showed a significant steadily decrease from the first to the fourth ripening stage that on average approached 38 %.Principal component analysis showed that lemon fruits at the ripening stages II and III were highly similar each other and well discriminated from the first and last ripening stages that also performed more distantly each other. The paper provides in-depth knowledge about the trend in AsA content and antioxidant activity of lemon juice across ripening.

Functionally active metabolites in two cultivars of chayote (Sechium edule(Jacq.) Swartz)

Chayote fruits (Sechium edule (Jacq.) Swartz) is a vegetable widely consumed by the Asiatic and Latino-American population, but little is known about the nutraceutical potential of different varieties. This study aimed to determine the chemical compositions and antioxidant activities of fruits from two commercial varieties of chayote cultivated in Mexico. The physicochemical properties of juice from S. edule var. virens levis (VL) and var. nigrum spinosum (NS) were determined using standard methods. Dried fruits were extracted successively with methanol and ethanol for chemical analysis and assessment of antioxidant (2,2-diphenyl-β-picrylhydrazyl test and β-carotene-linoleic acid test) properties. The juice of the two genotypes differed significantly regarding the concentrations of total soluble solids, total sugars, chlorophyll a, pH and colour, but not vitamin C. The total concentration of phenolics in NS extracts was slightly higher than in VL (1005 and 856 mg 100 g‑1 dry-weight, respectively) but the total flavonoid contents were similar (27 and 26 mg 100 g(‑1) dry-weight, respectively). Cucurbitacin D was predominant in both genotypes, while cucurbitacin B was higher in NS than in VL. The radical scavenging capacities of VL and NS extracts varied slightly (IC50=0.45 to 0.65 mg mL(‑1)), while the antioxidant activities were similar (~80%). In conclusion the two cultivars of chayote are chemically distinct, and the NS cultivar is particularly promising regarding nutraceutical application.

Nutraceutic Characteristics of the Extracts and Juice of Chayote (Sechium edule (Jacq.) Sw.) Fruits

Fruits of chayote [Sechium edule (Jacq.) Swartz] are a non-traditional vegetable widely consumed in Latin America, with the state of Veracruz, México being the world’s main producer, but little is known about the nutraceutical potential. This study aimed to determine the chemical compositions and antioxidant activities from the juice fruits from two commercial varieties of chayote cultivated in Mexico, as well as a proposal for the elaboration of chayote juices with stevia leaves and pineapple juice. The physicochemical properties of juice from virens levis (VL) and nigrum spinosum (NS) varieties were determined using standard methods. The juice of the two varieties differ significantly regarding the concentrations of total soluble solids and total sugars, but not vitamin C. The total concentration of phenolics in NS extracts was slightly higher than in VL (1005 and 856 mg 100 g−1 dry-weight, respectively), but the total flavonoid contents were similar (27 and 26 mg 100 g−1 dry-weight, respectively). Cucurbitacin D was predominant in both varieties. The radical scavenging capacities of VL and NS extracts varied slightly (IC50 = 0.45 to 0.65 mg mL−1), while the antioxidant activities were similar (~80%). The NS variety is particularly promising regarding nutraceutical application. The chayote juice combined with stevia and pineapple maintained the original nutraceutical characteristics of the fruit, but enhanced the organoleptic characteristics like density and sugar/acidity balance.

Evaluation of the effect of storage time and temperature on some physicochemical properties of juice and jam developed from two varieties of monkey kola (Cola parchycarpa, Cola lepidota)

This study was aimed at evaluating the effect of storage time and temperature on some physicochemical properties of juice and jam developed from two varieties of monkey kola (Cola parchycarpa, Cola lepidota). Two varieties of monkey kola (white and yellow) were purchased from Umuahia Main Market Abia State Nigeria from five randomly selected vendors and pooled to obtain the samples for the jam and juice production. The pH, total solid, soluble solid, titratable acidity, and total plate counts varied with storage time and temperature; the parameters studied were more stable in samples stored at refrigeration temperature (12oC) than those stored at ambient temperature (29-32oC). There was no significant change in specific gravity throughout storage period. Under ambient storage at week 4 C.parchycarpa jam had the least total plate count (42.5Cfu/g). Under refrigeration (12oC) Cola lepidota jam had the least (22.5Cfu/g) plate. C.parchycarpa juice was more stable than Cola lepidota juice at both ambient and refrigeration temperatures. From the result of this study, it can be concluded that the shelf-life of the products (jam and juice) can be extended by storing them in the refrigerator. Further investigation on how to keep the products longer is however recommended.

Development and Analysis of Blended Pineapple-Watermelon Ready To Drink (RTD) Juice.

The physicochemical properties of juice from pineapple and watermelon and their ready to drink (RTD) blends were carried out. The % watermelon juice and pineapple juice of each formulation (v/v) were BL1 (70:30), BL2 (60:40), BL3 (50:50), BL4 (30:70) and BL5 (40:60). The standards were done without blending the two juices SPJ (100% standard pineapple juice) and SWJ (100% standard watermelon juice). The results of the analysis of Vitamin C content (mg/g) gave 125.26 in SWJ, 38.90 in SPJ, 111.58 in BL1, 98.94 BL2, 86.31 BL3, 72.63 BL4 and 84.21 BL5 respectively. The vitamin C content of the RTD blends increase with high proportion of SWJ. The results revealed that all the blends especially 70:30 (watermelon: pineapple) gave an improved composition in terms of the physicochemical properties determined. Keywords: Physicochemical, blends, ready to drink, pineapple, watermelon, juice, vitamin C

Determination of organic acids, total phenolic content, and antioxidant capacity of sour Citrus aurantium fruits

Much attention recently has been paid to the possible he alth benefits of dietary phenolics that have antioxidant activities stronger than that of vitamin C. However, information concerning the antioxidant capacities of sour orange peel and juice is not available. So, the purpose of this research is to determine the organic acids, total phenolic content, total flavonoid cont ent, and antioxidant capacity of sour orange (peel and juice), which is grown in Turkey. Some physicochemical properties of juice and peel are given in Table 1. Since the predominant acid was found as citric for juice, and oxalic for peel (HPLC assay), total titratable acidity (TTA) of samples were calcu lated on the basis of the predominant acid. Karadeniz [5] reported pH as 2.6, TTA as 4.9 g/100g, and Brix as 10.0 in sour orange juice, which is similar to our results. 4 organic acids in juice and 3 organic acids in peel were detected and quantified. The predominant organic acid was found as citric (97% of total acids) in juice and oxalic in peel (54 % of total acids), respectively. The other acids were oxal ic, malic, and ascorbic in juice, and quinic and ascorbic in peel (Table 2). The recoveries of organic acids from the BondElut cartridges were within 87‐105%. In the calculation of final results, recovery rates were not taken into consideration. The sum of all quantified acids by HPLC in juice and peel were 3.9 g/100 mL and 0.5 g/100 g, respectively. Citric and malic acids of so ur orange juice from Antalya (Turkey) were reported by Karadeniz as 48.8 and 2.2 g/L, respectively [5]. Slight differences between the two studies are attributable to the fruit sources, ripeness, and analytical conditions used. The presence of ascorbic acid (only qualitative) in sour orange juice has been previously reported [6]. The total phenolic content, total flavonoid content, and EC 50 values of the samples are given in Table 3. In the literature, there are no published results for sour orange, so the total phenolic content of sour orange peel and juice was compared with the total phenolic content of different citrus fruits analyzed with the same method. Gorinstein et al. reported that peeled lemons, oranges, and grapefruit contain 164±10.3, 154±10.2, and 135±10.1 and their peels 190±10.6, 179±10.5, and 155±10.3 mg gallic acid equivalent/100 g of total polyphenols, respectively [7]. The total flavonoid content of grapefruit peels was found between the ranges 74.4‐95.2 mg /100 g fresh weight [8]. In our study, both total phenolic content and total flavonoid content of sour orange peel were higher than literature values of different citrus f ruit peel such as lemon, orange, and grapefruit. It can be seen with increasing total phenolic content, the EC 50 value decreases, so the necessary amount of sample needed to decrease the initial DPPH· concentration (EC 50 ) by 50% becomes lower [9, 10]. Another term for antioxidant capacity is antiradical efficiency (AE), which is widely used to compare the results. Higher AE means higher antioxidant activity. As can be seen in Table 3, the total flavonoid content of peel was approximately 50-fold higher than juice where the total phenoli c content was 8-fold higher. Also the percentage of total flavonoid content to total phenolic content was higher in peel (~80 %) than juice (~14 %).