Open Access Original Research Article

Effect of Frying Temperature and Time on Thermophysical Properties and Quality Attributes of Deep-Fat Fried Plantain (Dodo)

J. A. Adeyanju, B. E. Alabi, A. O. Abioye, A. A. Adekunle, A. A. Oloyede

Asian Food Science Journal, Page 1-6
DOI: 10.9734/afsj/2021/v20i1230386

This study investigated the effect of the processing conditions (frying temperature and time) on the thermophysical properties and product quality attributes of deep-fat fried plantain (dodo). The plantain were deep-fried at various frying temperatures (150-190 °C) and time intervals (120-240 sec). The thermophysical properties determined include specific heat, thermal conductivity, thermal diffusivity and density. The product quality attributes were moisture content, oil content and colour. The specific heat, thermal conductivity, thermal diffusivity and density of the deep-fat fried plantain ranged from 2.68 to 2.33 kJ/kgK, 0.37 to 0.33 W/mK, 1.12 to 1.36 x10-7 m2/s and 1049.50 to 1257.00 kg/m3, respectively. The quality attributes of dodo varied from 0.24 to 0.65 abs, 30.37 to 43.40% and 9.96 to 14.25% for colour, It was observed that the specific heat, thermal conductivity, thermal diffusivity and moisture content of the deep-fat fried plantain were significantly reduced as frying temperature and time increased. The colour and fat content of dodo were found to increase with increased temperature and time of frying. Outcome of the study resulted in the development of dodo with high acceptable quality characteristics. Therefore, generated data will be useful in choice of processing conditions for plantain and development of fryer.

Open Access Original Research Article

Effects of Different Extracting Solvents on Non-Phenolic Phytochemical Profiles of Selected Nigerian Spices and Spice-treated Foods

F. U. Ugwuona, O. E. Agwo, A. N. Ukom, B. N. Iguh

Asian Food Science Journal, Page 7-17
DOI: 10.9734/afsj/2021/v20i1230387

The aim of this research was to investigate the impact of extraction solvents on the non-phenolic phytochemical profiles of selected spices (Ocimum viride, Monodora myristica, Monodora tenuifolia and Tetrapleura tetraptera) and spice-treated foods in southern part of Nigeria. The spice samples were processed into powder for antioxidant screening. The spice extracts were obtained from the samples using 5 extracting solvents [distilled water, 95 % methanol, acetone / hexane (1:1 v/v), n-hexane / methanol / acetone (2:1:1, v/v/v) and acetone / water / acetic acid (70:29.5:0.5, v/v/v)]. Water extracts were obtained from beef, pork and fluted pumpkin leaves. The alkaloid, saponin, oxalate and phytate components of the spice extracts and the spice-treated foods were evaluated using standard methods. The laboratory analyses were performed at analytical laboratory, National Centre for Energy Research and Development, University of Nigeria, Nsukka during the 3rd quarter of 2020. The percentage yield of the extracts were low (0.32 - 0.96 %) and varied widely among extracting solvents, spices and spice-treated foods. M. myristica and T. tetrpleura had the highest yield, 0.96, in methanol extracts. Phytochemical contents differed significantly (p < 0.05) among spices, extracts of the same spice and among spice-treated foods. Spices had high contents of oxalate (2.0 – 7.0 mg/100 g), alkaloid (0.8 – 5.76 mg/100 g) and phytate (2.14 – 3.88 mg/100 g) but relatively low content of saponin (0.03 – 0.736 mg/100g). Methanol alone or in combination with other solvents extracted higher amounts of phytochemicals (0.96 %) than other solvent mixtures from the spices. Phytochemical contents of spice-treated foods were in the order: vegetable > rice > pork > beef.

Open Access Original Research Article

Physicochemical, Functional and Pasting Properties of Garri Fortified with Soybean Flour

P. C. Obinna-Echem, P. A. Amgbeye

Asian Food Science Journal, Page 18-27
DOI: 10.9734/afsj/2021/v20i1230388

Aim: This study evaluated the physicochemical, functional and pasting properties of garri fortified with soybean flour.

Methodology: Soybean flour was incorporated into the garri prior to garrification at a ratio of 10, 20, 30, 40 and 50% for samples A, B, C, D and E respectively. Sample without soybean flour served as control. Standard analytical procedure was used in the evaluation of all six samples.

Results: The pH and titratable acidity (TTA) of the samples varied respectively, from 4.59 - 6.48 and 0.08 - 0.17 % lactic acid. There was significant (P<0.05) decrease in pH with increase in soybean flour, while the reverse was the case for TTA. Swelling power, bulk density and water absorption capacity of the soybean fortified garri ranged from 8.74 - 17.81%, 0.60 - 0.80 g/ml and 13.44 – 19.43 % respectively. Control sample (100% garri) had hydrogen cyanide (HCN) content of 1.50 mg HCN/100g while samples with soybean flour had no detectable levels. Peak viscosity, trough, breakdown, final viscosity and setback varied significantly (P<0.05) from 101.19 - 399.44, 90.92 - 320.19, 10.28 - 79.25, 123.19 - 451.50 and 32.28 - 131.31 RVU respectively. Peak time and pasting temperatures ranged from 5.18 – 6.34 min and 74.28 – 92.88 oC.

Conclusion: The study revealed that a good quality garri can be produced with the incorporation of soybean flour up to 50%, the garri is safe for consumption as there was no HCN detected, and the decrease in viscosity provides for a soft textured, mouldable garri that is convenient for swallow.

Open Access Original Research Article

Physicochemical, Anti-Oxidant and Sensory Characteristics of Spiced Jam from Blends of Selected Tropical Fruits

O. A. Adeoti, A. O. Alabi, O. O. Elutilo

Asian Food Science Journal, Page 28-40
DOI: 10.9734/afsj/2021/v20i1230389

Jams are preserved fruits and sugars which are packaged in cans or bottles for long-term preservation. The processing involves the disruption of the fruit tissue followed by heating with water and sugar to activate the pectin prior being put into containers. Jams were processed from two selected tropical fruits namely, pineapple and watermelon. The jam produced was spiced with ginger and turmeric at 5% level using a standard methods. The treatments are WA (watermelon 100%), WAG (watermelon 95% + ginger 5%), WAT (Watermelon 95% + turmeric 5%), WAGT (watermelon 95% + ginger 5% + turmeric 5%), PI (pineapple 100%), PIG (pineapple 95 % + ginger 5%), PIT (pineapple 95% + turmeric 5%) and PIGT (pineapple 95% + ginger 5% + 5% turmeric). The proximate, physiochemical, antioxidant, total phenolic, color and sensory characteristics of the spiced jams were determined using standard analytical procedures. The proximate result showed that the moisture content of the samples ranged from 3.61-20.55% for Watermelon jam (WA) and reference sample (CNTP); protein 0.50-5.16% for (CNTP) and watermelon-ginger jam (WAG); fat and ash contents were 0.21-2.55% and 0.38-1.53% for (CNTP) and pineapple jam (PI) respectively. The pH of the spiced jam ranged from 3.10-3.40 for (CNTP) and (WAG) while the sugar brix ranged from 69.80-79.50° brix. The titratable acidity of the samples ranged from 1.03-1.06 g/ml for pineapple-turmeric jam (PIT) and (CNTP).The TSS/TTA ratio was 52.88 and 5.39 for (CNTP) and (WA) respectively. The antioxidant properties of the sample ranged between 31.39-50.67% for (WA) and (PIG). Total phenolic content was 0.14-0.25 MM GAE/ 100 ml for watermelon jam (WA) and (PIT). The L*, a* and b* values for the samples ranged from 23.23-33.16, 1.05-6.69 and 3.35-13.55. The result for sensory scores of the spiced jams ranged from 5.66-7.98 and 6.20-7.88 for color and taste respectively while the mouth feel was 5.05-7.46. The overall acceptability scores ranged from 6.40-7.90. Conclusively, pineapple and watermelon jams spiced with ginger and turmeric were nutritious and acceptable, however, pineapple-ginger jam was most nutritious and acceptable, hence, pineapple-ginger jam can be utilized as a functional food and can also contribute to the improvement of Nigeria food composition database.