Cassava (Manihot esculenta Crantz) roots (tubers) are used as staple food. Starch extracted from tubers is widely utilized as raw materials in industries. Dry matter (DM) content, starch and flour extraction and proximate composition were investigated in seven cassava accessions (Coc-A 1, Kh-A 2, Cow-A 3, Sa-A 4, Me-A 5, Va-A 6 and Sy-A 8. ) in 2010-2011. Leaf DM varied from 20.51% in Me-A 5 to 29.01% in Sy-A 8 ; that of stem from 27.24% in Va-A 6 to 32.10% (average of Sy-A 8 , Me-A 5 and Sa-A 4 ); and that of tuber from 37.30% in Kh-A 2 to 45.26% in Sy-A 8 . Starch was extracted by blending chopped tuber followed by decantation. Tubers were sliced, sun dried and milled into flour. Tuber starch content (fresh wt. basis) varied between 15.04% in Sy-A 8 and 24.97% (average of Coc-A 1 and Me-A 5 ); that of peel from 4.54% in Va-A 6 to 5.85% in Coc-A 1 . Crude protein varied from 1.80% (average of Kh-A 2 , Cow-A 3 and Sy-A 8 ) to 4.53% in Va-A 6 . Crude fiber content varied from 1.95% (average of Sa-A 4 and Coc-A 1 ) to 4.27% in Cow-A 3 . Cyanogens present in cassava plant escape as hydrogen cyanide (HCN) during harvesting and processing. Variation for HCN existed and it was 140.95 mg/kg fresh tuber (average of Sy-A 8 and Coc-A 1 ) to 546.0 mg/kg fresh tuber in Va-A 6 . There was no detectable HCN in the extracted flour and starch. It may be concluded that genetic variation for DM, starch, protein and HCN existed in seven cassava accessions, and Coc-A 1 may be a better one due to its lower HCN, higher DM and starch content.

This experiment was conducted to evaluate the effect of chitosan coating on physiological responses and nutritional qualities of tomato fruits at postharvest storage. There were four treatments of chitosan viz. T0 (control), T1 (0.10%), T2 (0.20%) and T3 (0.30%), and two storage conditions viz. in refrigerator (4°C) and room temperature (≈23-25°C). The matured light yellow tomato fruit samples were collected at 10, 20, 30 and 50 days after postharvest storage to assess physiological parameters viz. shelf life and weight loss as well as to determine lycopene and mineral constituents viz. Ca, Mg, P, S, Na and K. The mean weight loss of tomato fruits were 0.64, 1.28, 1.59 and 2.28% at 4°C, while it was 0.88, 1.84, 2.60 and 4.80% at room temperature at 10, 20, 30 and 50 days after postharvest storage, respectively. The shelf life of tomato fruits ranged between 58.3-100.0, 50.0-100.0, 33.3-75.0 and 16.7-66.8% at 4°C, while the ranges were 66.8-100.0, 50.0-100.0, 33.3-75.0 and 0.0-41.8% at room temperature at 10, 20, 30 and 50 days after postharvest storage, respectively. As regards to weight loss and shelf life, the study results inferred that chitosan coating with 0.2% solution is useful at postharvest storage of fruits. The study results revealed that storage temperatures (4°C and ≈23-25°C) had no effect on the total contents of different mineral element of tomato fruits but lycopene content reduced almost twice at refrigerated condition. On the other hand, the effect of chitosan coating on Ca, Mg, P, S, Na and K contents of tomato fruits at different days after postharvest storage were highly significant at both conditions. Finally, the study results concluded that 0.2% chitosan based coatings in tomato fruits proved to extend the shelf life by decreasing the decay incidence and weight loss, and refrigerated condition is better than that of room temperature.

Black pepper (Piper nigrum) is a spice vine crop which is used as a food preservative and as an essential component in traditional medicines. The aim of this study was to extract, isolate and characterize the structure of piperine. The fruits of black pepper were extracted in ethanol and compounds present identified by TLC under iodine vapour. A compound (A 2 ) having R f value 0.54 was isolated by column chromatography which may be responsible for the pungency of black pepper. After recrystallization of the isolate with benzene and chloroform mixture (7:1) gave pale yellow crystals of m.p. 128~129 o C (reported 130 o C). The IR, 1 H NMR and mass spectra of the pure crystalline compound (A 2 ) were recorded. The mass spectra of the compound (A 2 ) showed molecular ion peak M +· at 284.5 which was similar to that of piperine (mol. wt. 285).

A pot experiment was conducted to study the effect of different application methods of chitosan on growth, yield and quality of tomato (Lycopersicon esculentum Mill.). The experiment was laid out in completely randomized design (CRD) with four replications and twelve treatments combinations viz.

An experiment was conducted to study the nutritional qualities of industrially processed tomato ketchups compared to homemade one and to assess metallic heath risk due to consumption of those ketchups. Eight different types of industrially processed tomato ketchups available in the markets of Bangladesh from dissimilar producers and one homemade sauce were analysed in this study. Dry matter content in industrially processed tomato ketchups ranged between 32.52-38.41% while it was only 7.90% in case of homemade sauce. The average lycopene content of industrially processed tomato ketchups was 20.02 mg 100g-1 sample while it was 29.10 mg 100g-1 sample for homemade tomato sauce. Among the mineral nutrients- Ca, Mg, P and K contents in homemade tomato sauce were higher compared to industrially processed one. But Na content was higher in different industrially processed ketchups. Concentrations of Cu, Zn, Cr, Pb, Ni, Cd and Mn in industrially processed tomato ketchups ranged between 5.29-6.82, 2.14-34.08, 6.48-9.05, 7.56-11.51, 0.12-0.95, 0.36-0.46 and trace µg g-1 (fresh wt. basis), respectively while in case of homemade tomato sauce the mean concentrations were 2.12, 3.33, 1.66, 2.08, 0.13, 0.09 and 1.73 µg g-1 (fresh wt. basis), respectively. Thus, present study results inferred that higher amount of different heavy metals might be contributed by the addition of spices and other ingredients to industrially processed tomato ketchups. Target hazard quotients (THQ) values for Pb and Cr for industrially processed tomato ketchups approached or surpassed 1 for female. The cumulative target hazard quotients (CTHQ) values for the same tomato ketchups were also greater than one (>1) for both male and female, which indicate that the exposed populations are in a level of concern interval. On the other hand, individual THQ and CTHQ values for homemade sauce were less than 1 for both male and female, which indicate that dietary intake of this sauce is assumed to be safe.