Browsing by Author "Chove, Lucy M."
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Item Effect of solar drying methods on total phenolic contents and antioxidant activity of commonly consumed fruits and vegetable (mango, banana, pineapple and tomato) in Tanzania(Academic Journals, 2015-05) Mongi, Richard J.; Ndabikunze, Bernadette K.; Wicklund, Trude; Chove, Lucy M.; Chove, Bernard E.The effects of solar drying methods [Cabinet direct (CDD), cabinet mixed mode (CMD) and tunnel (TD) drying] on total phenolic content (TPC) and antioxidant capacities of commonly consumed fruits and vegetable in Tanzania were investigated. The TPC and FRAP in mangoes (Mangifera indica cv. Dodo, Viringe and Kent), bananas (Musa acuminata, cv. Kisukari, Kimalindi and Mtwike), pineapples (Ananas comosuss cv Smooth cayenne) and tomatoes (Lycopersicum esculentum cv. Tanya, Cal J and Onyx) were evaluated using Folin-Ciocalteu reagent and ferric reducing antioxidant power (FRAP) methods, respectively. There were significant (p<0.05) variations in TPC (mg GAE/100 g DM) and FRAP (μmol/100 g DM) among the fresh fruit and vegetable samples. The highest TPC was in tomato (476.6±8.6 - 538.9± 1.4) and lowest in banana (139.3±2.3 - 189.2±2.7). Drying methods had significant (p<0.05) effect on TPC and antioxidant values of the samples. All fresh samples had higher TPC levels but declined significantly in dried samples with the exception of tunnel dried tomatoes. Among the dried samples, the tunnel dried samples had less TPC loss (6-16%) than the cabinet dried samples (17-42%). The cabinet direct and mixed mode samples were not statistically different (p>0.05) from each other. However, tunnel dried samples had less FRAP loss (6-13%) which were statistically different (p<0.05) from the cabinet dried samples (14-56%). Percentage TPC and FRAP recoveries (%) differed significantly (P<0.05) between the varieties within the fruits/vegetable for both drying methods. A strong 2 2 correlations between TPC and FRAP in both fresh (R = 0.970) and dried samples (R =0.8636) suggests that solar drying methods have significant effects on total phenolic contents and antioxidant activities of fruits and vegetables with tunnel drying method giving significantly less effects.Item Effects of Hexanal and Calcium Chloride Post-Harvest Treatments in Management of Fresh Mango (Mangifera indica) Quality(Springer, 2022-07) Baltazari, Anna; Mtui, Hosea D.; Mwatawala, Maulid W.; Chove, Lucy M.; Msogoya, Theodosy; Samwel, Jaspa; Paliyath, Gopinadhan; Subramanian, JayasankarAbstract Experiments were conducted at the Sokoine University of Agriculture to assess the effects of hexanal at (0.02%) (volume/volume) and calcium chloride (2%) (weight/volume), on post-harvest quality of mango (‘Palmer’ and ‘Apple’) under different storage conditions and durations. A three factors factorial experiment was used for each variety and replicated six times. The fruits were stored at ambient temperature (28 ± 2 °C) or reduced temperatures (18 ± 2 °C) storage conditions. Data included physiological weight loss (PWL), fruit firmness, total soluble solids (TSS), titrat- able acidity (TA), TSS/TA ratio, vitamin C, total flavonoids, reducing sugar and total sugars which was collected at 0, 4, 8 and 12 days after harvest. Results indicated that hexanal and calcium chloride significantly (p \ 0.001) reduced mango PWL and improved fruit firmness and TSS of both varieties compared to untreated fruits. Hexanal-treated fruits maintained high vitamin C, total flavonoids, total and reducing sugars irrespective of the storage conditions. Vitamin C and total flavonoids of mango fruits decreased with storage time, whereas total and reducing sugar contents increased with storage time. Both treatments maintained physico-chemical qualities of mango fruits, when stored under reduced temperature storage. Keywords; Physiological weight loss , Fruits firmness , Total soluble solids (TSS) , Titratable acidity (TA) ,TSS/TA ratio , Vitamin C , Flavonoids , Reducing sugar , Total sugarItem Effects of storage conditions, storage duration and post-harvest treatments on nutritional and sensory quality of orange (Citrus sinensis (L) Osbeck) fruits(Taylor & Francis Group, 2019-10-15) Baltazari, Anna; Mtui, Hosea D.; Mwatawala, Maulid W.; Chove, Lucy M.; Msogoya, Theodosy; Samwel, Jaspa; Subramanian, JayasankarThe fruits of Msasa and Jaffa orange varieties were harvested and subjected to post-harvest treatments namely; dipping in hexanal, dipping in calcium chloride and compared with untreated control; and they were stored at ambient (28 ± 2° C) and reduced temperatures (18 ± 2°C) conditions. Data were collected on the 0, 4 th , 8 th , and 12 th days from the date of fruit harvest. Chemical analyses were conducted to determine vita- min C content, total sugars, reducing sugars and total flavo- noids. Post-harvest treatments had a significant effect on vitamin C and total flavonoids of Jaffa orange fruit. Hexanal treated fruit had higher values of total flavonoids, vitamin C, and total sugars compared to calcium chloride treated and control fruit. The storage durations showed significant effects on the vitamin C content of Jaffa, total flavonoids, the total and reducing sugars of both fruit varieties. Vitamin C and total flavonoids decreased with increasing storage duration of fruit. The significant interactions of factors were observed on total sugar which was increasing with increasing storage duration, but higher in hexanal treated and ambient stored fruit. Based on consumer acceptance test, the hexanal treated fruits were the most liked followed by calcium chloride treated and untreated fruits based on the appearance, taste, texture and overall acceptability.Item Microbiological quality of stream and borehole water in Lushoto district, Tanzania(African Journal of Environmental Science and Technology, 2023-03-14) Chove, Lucy M.; Athumani, HadijaA study was conducted to assess the microbiological quality of water in two streams and three boreholes from Sunga and Mbaru wards in Lushoto district, Tanzania. Water samples were collected in duplicate from the streams and boreholes. Three locations were selected along the stream including unpopulated forest areas, highly populated and less populated areas both with agricultural activities. Analysis of data was done by R-Software and means separated by Turkey‘s honest significance test at p<0.05. Significant differences (p<0.05) in Escherichia coli and Salmonella contamination were observed along the three locations of the streams. Although the unpopulated forest areas were not contaminated by either microorganism except for one sample, the rest of the areas were contaminated. Highly populated agricultural areas were found to be contaminated by E. coli and Salmonella, followed by the less populated agricultural areas. Generally, water samples from the streams failed to meet the TZS 789 Standard and WHO 2011 water guidelines, a risk to water borne disease outbreaks. With the exception of E. coli from boreholes in Madukani, all other borehole water samples were within the limits stipulated in both the TZS 789 Standard and WHO 2011 Guidelines. Communities should be warned about the dangers of water contamination especially at the sources. In addition, water should be treated regardless of its source to improve its safety and quality for human consumption.Item Reduction of preharvest and postharvest losses of sweet orange (citrus sinensis l. osberck) using hexanal in Eastern Tanzania(John Wiley & Sons, Inc., 2019) Mwatawala, Maulid W.; Baltazari, Anna; Msogoya, Theodosy J.; Mtui, Hosea D.; Samwel, Jaspa; Chove, Lucy M.Fruits are rich in phytochemicals that protect human populations against diseases (Hung et al. 2004; Dauchet et al. 2006; Bellavia et al. 2013). Nutrients contained in fruits include essential vitamins, minerals, antioxidants, fibers, and carbohydrates that improve the quality of the human diet (Barrett 2007). For example, sufficient daily consumption of fruits can reduce the risks of diabetes, hypertension, heart diseases, and certain types of cancer (Bazzano et al. 2002; Yao et al. 2004). According to FAO/WHO (2003), up to 2.7million lives could potentially be saved each year with sufficient intake of fruits and vegetables. Much of the world’s population, however, does not consume the recommended intake of at least 100g per day of fruits daily. Global production of citrus fruits increased from 144 876 944 tonnes in 2015 to 146 429 018 tonnes in 2016 (FAO 2017). This was coupled with increased global demand for fresh fruits (Weinberger and Lumpkin 2007). Sweet orange (Citrus sinensis L. Osberck) is an important tropical fruit with high global demand. Sweet oranges are consumed fresh or processed as juice. Although citrus production increased moderately in several countries in the last decade, it fell in the USA. However, citrus fruit continues to be an important crop for satisfying food and nutrition needs (United States Department of Agriculture 2018). Sweet orange is a good source of potassium, folate, and vitamin C (Turner and Burri 2013). Vitamin C is an antioxidant that lowers risks of cancer, cataract formation, and heart‐related diseases (Harats et al. 1998; Jacques et al. 1997). Folate is necessary for DNA and protein synthesis (Turner and Burri 2013), while potassium helps to maintain normal blood pressure. Sweet orange also contains phenolic compounds that are important antioxidants (Rapisarda et al. 1999; Turner and Burri 2013). Production of sweet orange is a source of employment, income, and livelihood to large, medium, and smallholder farmers in various parts of the globe. Global production of sweet orange increased from 116 million tonnes in 2008 to 124 million tonnes in 2017 (FAO 2017). However, despite the demand due to the nutritional and health benefits, many fruits are highly seasonal and perishable with high preharvest and postharvest losses and wastages (Idah and Aderibigbe 2007). Postharvest losses in fruits and vegetables were estimated to be 30–40% in developing countries (Karim and Hawlader 2005). This chapter presents findings from trials on the effectiveness of different preharvest and postharvest treatments on orange fruit quality. The chapter also provides background information on production, socioeconomic importance, and constraints to orange production in Tanzania.