Browsing by Author "Samwel, Jaspa"

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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, Jayasankar
Abstract 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 sugar
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, Jayasankar
The 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.
Evaluation of post-harvest losses and shelf life of fresh mango (Mangifera indica L.) in Eastern zone of Tanzania
(Taylor & Francis Group, 2019-12) Baltazari, Anna; Mtui, Hosea; Chove, Lucy; Msogoya, Theodosy; Kudra, Abdul; Tryphone, George; Samwel, Jaspa; Paliyath, Gopinadhan; Sullivan, Alan; Subramanian, Jayasankar; Mwatawala, Maulid
Post-harvest loss negatively impacts food security, nutrition and economic stability of farmers, exporters, traders and consumers. Experiments were conducted to assess the effects of post-harvest techniques on the shelf life of Apple and Palmer mango cultivars under different storage conditions. Post-harvest losses of these fruit along the supply chain were also evaluated. A two-factors factorial experiment with six replications was used for each culti- var. Post-harvest techniques included dipping of fruit in hexanal solution (0.02% v/v), calcium chloride solution (2% w/v), smoke treatments and untreated fruit. The fruit were then stored at two different storage conditions namely: ambient temperature (28 ± 2°C) and cold storage (18 ± 2 ° C). Shelf life data was analyzed by using R-software. Mean separation was done by using Tukey Honestly Significant Difference at (p ≤ 0.05). Results showed that the major sites of post-harvest losses were at harvest, transport, wholesale and retail stages of supply chain. Furthermore, post- harvest treatments of fruit with hexanal and calcium chloride significantly increased shelf life and reduced disease incidences compared to untreated control and smoke-treated fruit. Cold storage significantly increased shelf life of mango fruit compared to ambient storage. Therefore, hexanal, calcium chloride and cold storage are recommended to extend fruit shelf life, maintain fruit firmness and to reduce disease incidences in mango fruit.
Identification Of Drought Torelant Varieties Of Common Bean (Phaseolus Vulgaris L.) In Tanzania
(Sokoine University of Agriculture, 2008) Samwel, Jaspa
The aim of this research was to assess for levels of drought tolerance among common bean (Phaseolus vulgaris L.) lines developed for drought tolerance; grown under non-stress (NS) and drought-stress (DS) water conditions. The research was conducted at Sokoine University of Agriculture (SUA) located at 6 0 5’ latitude south, 37 0 3’ longitude east and 525 m.a.s.l. It was done in a screen house. The experimental design was Completely Randomized Design (CRD), two water regimes and twelve bean lines were combined in split- plot arrangement. Water regimes were the main plots and bean lines were sub-plots. The soil in pots was irrigated to 95 ± 5% field capacity (fc) which was determined by a tensiometers reading. Three seeds were planted in each pot, after germination (7-10 days) thinning was done to leave two (2) uniform bean plants in each pot. Then the NS and DS treatments were initiated at two weeks after germination. For non-stress (NS) treatment, irrigation was done once/day depending on the requirements of the plant and environmental conditions receiving water to make 95 ± 5% field capacity, which kept the plant water-stress free. In drought stress, watering was cut down to mimick a drought condition. Stress was imposed starting at different stages i.e. before flowering, at podding and thereafter stress condition was maintained at 20 ± 5 % fc. Data were collected for plant height, pod length, leaf area, number of seeds per pod, number of pods per plant and seed weight per plant. The results showed that some lines had a high capacity for tolerating DS conditions namely RWR 109, UBR (92) 09, MMS 243, CNF 5547, HHL MD 30-75 and G 4523.
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.