ABSTRACT
The notion of fruit and vegetables (FV) in preventing chronic diseases has long been discerned. To meet the recommended FV intake, FV juices have emerged as a convenient and healthy choice. Mixed fruit and vegetable juices (MFVJ) cater the blend of desirable flavor and taste of consumers. This study was carried out to determine the total phenolic content (TPC), antioxidant activities and sugar content of selected MFVJ. Folin-Ciocalteu assay was employed to quantify TPC, whereas DPPH and FRAP assays were used to evaluate the antioxidant activities of MFVJ. The sugar content was determined using phenol-sulfuric acid method. MFVJ extracted from bitter gourd, green apple and orange (BGO) had the highest TPC content (76.4 ± 4.2 mg GAE/100 ml). Celery and green apple (CG) juice showed the highest DPPH value (522.3 ± 7.6 mg TE/100 ml) whereas carrot and starfruit (AS) juice have the highest FRAP value (419.6 ± 21.6 mg TE/100 ml). The sugar content of MFVJ was within the range of 5.7-13.3 g/100 ml. MFVJ can be considered as healthy beverages with considerable amounts of phenolic compounds and low sugar content. This study provides some useful reference for consumers who consume juices with combinations of FV. Future studies need to discover more combinations of FV juices, providing more data pertaining to MFVJ. Identification of individual phenolic compounds should also be part of future research using various instrumental analyses.
ABSTRACT
Aims: To determine the survival rates of bacteria in contaminated fresh fruit juice samples Place and Duration of Study: Biosciences and Biotechnology Department, Babcock University, Ilisan Remo, Ogun State, Nigeria, between November, 2012 and May, 2013. Methodology: Freshly extracted juice samples were obtained from intact pineapple (Ananas comosus Merr.) and watermelon (Citrillus lanatus Thunb.) were pasteurized before being contaminated with Escherichia coli ATCC 25922 and Lactobacillus acidophilus. While the pH and the sugar contents were determined at interval after being contaminated with the bacterial strains, the contaminated juice samples were sampled for 150 min to determine colony forming unit per milliliter (cfu/ml) at different sampling time. Results: In pineapple juice, the log of concentration of E. coli was reduced from 6.452 at 0 min to 5.079 at 150min. In watermelon, the log of concentration of E. coli was reduced from 6.301 at 0min to 5.954 at 150min. While the log of concentration of L. acidophilus in pineapple juice was between 6.204 at 0 min and 6.262 at 150min, its log of concentration in watermelon juice ranged between 6.228 at 0 min and 6.291 at 150min. The pH was reduced to 2.9 and 3.7 by E. coli while L. acidophilus reduced the pH to 2.5 and 3.0 for pineapple and watermelon juices respectively. After 150min, the sugar contents of pineapple and watermelon juices decreased from 1.181 and 1.060mg/ml to 0.011 and 0.004mg/ml by the E. coli while L. acidophilus reduced the sugar contents to 0.003mg/ml for pineapple juice and 0.018mg/ml for watermelon juice. The reduction in the pH values of each of the fruit juices showed that the activities of each bacterial strain resulted in increase in the production of acid in the growth medium. Conclusion: The inability of coli form (E. coli) to survive in the fruit juices suggested that the fruit juices may not harbor and/or disseminate enteric pathogens if allowed to stay for a while before packaging.
ABSTRACT
In our experiment we tried to find out what kind of eventual changes in the environment and in plant chemical composition occurred in response to different fertilizer treatments applied to sweet corn (Zea mays convar. saccharata) grown on sandy soil with low humus content. The ploughed layer contained <1% CaCO3 and around 1% humus. The soil was very well supplied with P, well supplied with K, Mg, Mn and Cu, and weakly supplied with N and Ca. The treatments were planned in accordance with the recommendations, with a planned unhusked ear yield of 16 tons per hectare, of the new environmental friendly advisory system recently elaborated for field vegetable crops in Hungary. The treatments applied included: G1 (blank control) N0P0K0, G2 N222.5 P22.2 K143, G3 N445 P22.5 K143, G4 N222.5 P22.5 K143, G5 N222.5 P22.5 K286, G6 N222.5 P22.5 K143+Mg1.52. According to our findings, of the composition parameters of the grains of the treatments with no fertilizer application, the invert and reducing sugar contents (4.42%, respectively 2.59% relative to fresh weight-1) in grains were the highest among the treatments. The same conclusion was drawn on the K 120.2, Mg 13.3, Fe 0.24, Cu 0.66 mg 100 g-1 grain dry weight levels among minerals. In the case of the basic treatment (G2) recommended by the advisory system we obtained favourable results for the measured parameters, including yields. Invert and reducing sugar contents were (3.26% respectively 1.97% relative to fresh weight-1), and mineral contents K 101.9; Mg 11.8; Fe 0.21; Cu 0.56 mg 100 g-1 dry weight. In the grains, no translocation of toxic elements was observed in response to the direct or indirect effect of the treatments.