Assessment of Osmotic Pre-Drying Treatment on Drying Rates of Fresh Tomato Fruits

The aim of this work is to investigate the influence of osmotic pre-drying treatments on drying rates of tomato (Lycopersiconesculentum) at various drying temperatures. Fresh Roma tomato fruit samples were sliced to a thickness of 5 mm and the seeds were removed. Weight of 300 g was measured for each of the three replicates and immersed in a hypertonic solution of sucrose of different concentrations 40 and 60 oBrix each held for osmotic duration of 1 and 2 hours, drained for 10 min and then dried at 50, 60, and 70 oC in a mechanical dryer. Control samples were also weighed 300 g per replicate and dried at 50, 60, and 70 oC without pre-drying treatment. The initial moisture content of fresh tomato used was 94.5% (wb). Moisture loss of each sample was monitored and recorded hourly until the product has reached the desired final moisture content (≤ 7%).The data collected were subjected to statistical analysis of variance (ANOVA) and Duncan New Multiple range tests (DNMRT) to ascertain the level of significance differences between the individual treatments and their interaction at p ≤ 0.05.The results show that at all the drying temperatures used, the control tomato samples exhibited the fastest drying rate with an average of 35.2 g/hr, samples pre-treated at 40 oBrix has an average drying rate of 26.6 g/hr, while samples pre-treated at 60 oBrix has the slowest drying rate of 25.2 g/hr. It was also revealed that samples subjected to 1 hour osmotic time have faster drying rates than those treated for 2 hours osmotic time.KEYWORDS: Tomato; Osmotic duration; Brix concentration; Drying temperature; Drying rat

Effects Of Temperature And Time On The Moisture Content Colour And Texture Of Okra

The effects of drying temperature and time on okra (Hibiscus esculentis) was investigated. The moisture content, colour and texture of the okra were estimated. A model was developed to meet the required safe storagemoisture content, using data drawn from 22 factorial conducted in triplicates. The colour and texture parameters were statistically evaluated using chi-square. The results showed that a temperature of 650c and a drying time of 5 hours are most appropriate for drying okra to safe storagemoisture content of 3.2% dry basis (0.032 db). At P< 0.05 results showed that there was significant deference in colour and no significant differences in the texture of freshokra samples and dried samples

Palm kernel shell as aggregate for light weight concrete

In this study, the effect of replacing the conventional gravel with palm. kernel shell as aggregates in making concrete was inquired into. Several . volumes of palm kernel shells were used in two (4) different proportions with the other constituents and the strength of the concretes produced were tested to ascertain the effect of the replacement on the concrete produced. The palm kernel, cement, sand and gravel were mixed and cast in steel or cast iron moulds of 150mm2 cubes. The results show that the PK1 with ratio of 1 :2:3: 1· of cement, sand, gravel. and palm kernel shells respectively gave the highest compressive strength of 8.03N/mm2 after 28 days of curing. Comparing the results of the tests with some standards, it was observed that 64% of the samples of the concretes produced with this partial replacement conform to the standard after 7 days of curing.Keywords: Aggregate, Cement, Concrete, Sand, Palm Kernel Shell