Effect of Combined Processing Methods on the Functional and Pasting Properties of Pigeon Pea (<i>Cajanus Cajan</i>) Flour

Abstract

Abstract:The study investigated the combined effects of different processing methods of pigeon pea on the functional and pasting properties. Soaked pigeon pea seeds (control) were subjected to sprouting, boiling, fermentation and combinations of these operations and the seeds were dried and milled into flour. The functional and pasting properties of the flour samples were analyzed using standard methods. The result of the functional properties showed that combined sprouting/fermentation reduced bulk density (0.647 -0.599g/cm 3 ), increased water absorption capacity (1.683 -1.803%), increased oil absorption capacity (1.623 -1.634%), increased swelling capacity (2.077 -2.1625) and decreased foam capacity (13.213 -12.232%). The pasting results recorded low values for sprouted and combined processes and high values for fermented processes in peak viscosity, trough viscosity, pasting temperature and peak time.

Effect of Germination Time on the Properties of Flours from Red and Brown Varieties of Pigeon Pea (Cajanus cajan) Seeds

“…The reduction in the bulk density observed in all the germinated samples could be due to solubilization of starch polymers during processing as a result of steeping and germination treatments [26]. The observation is in agreement with the report of Arukwe et al [3] who stated that germination resulted in the reduction of the bulk density of the flours and other flour products. The bulk density is important in the selection of packaging materials and proper handling of food materials during processing and preparation of foods [27].…”

“…There were significant differences (p<0.05) in the peak viscosity of the flour samples. The increase in the peak viscosity of the germinated samples could be attributed to the increase in the activities of hydrolytic enzymes which degraded the starch molecules into simpler sugars during processing as a result of steeping and germination treatments [3]. Germination has been reported to increase the peak viscosity of food materials [26].…”

“…There were significant differences (p<0.05) in the setback viscosity of the flour samples. The reduction in the setback viscosity of the germinated samples could be attributed to the increase in the activities of hydrolytic enzymes which degraded the starch molecules into simpler sugars as a result of steeping and germination treatments during processing [3]. The reduction in setback viscosity of the flour samples is an indication of low rate of retrogradation and syneresis tendency of the pastes prepared from the flours.…”

“…Although it is a perennial herbaceous leguminous plant, it is cultivated at subsistence level in Nigeria with the existence of different varieties. Pigeon pea is mainly classified and consumed as lesser known and underutilized legume in Nigeria and other sub-Sahara African countries compared to other legumes like cowpea, soybean and kidney bean despite its numerous nutritional benefits which include the improvement of the level of malnutrition and boosting of food security [3,4]. It can also serve as one of the good sources of plant protein, vitamins, minerals and plant sterols.…”

“…Pasting properties are among the rheological characteristics of starch that are used to determine the behaviour of starch in a food system especially when an aqueous suspension of starch is heated above a critical temperature during processing [3]. Some of the important pasting properties that are commonly determined during the processing of starchy and leguminous food products are peak, trough, setback, breakdown and final viscosities, in addition to other parameters which include peak time and pasting temperature.…”