Date of Award
Doctor of Philosophy (PhD)
Environmental Engineering and Earth Sciences
Dil Thavarajah, Committee Chair
Pulses such as lentil (Lens culinaris Medikus), common bean (Phaseolus vulgaris L.), and chickpea (Cicer arietinum L.) are a rich source of protein, prebiotic carbohydrates, and micronutrients. Prebiotic carbohydrates are utilized by beneficial gut microorganisms and produce short chain fatty acids which is associated with increasing mineral absorption and reducing obesity risk. The objectives of these studies were to 1) identify and quantify prebiotic carbohydrate profiles [simple sugars, sugar alcohols (SA), raffinose family oligosaccharides (RFO), fructooligosaccharides (FOS), resistant starch (RS), cellulose, hemicellulose, and amylose)] in different market classes of lentil, common bean, and chickpea, 2) determine the changes of SA, RFO, FOS, RS, and amylose concentration in common bean and chickpea market classes in response to cooking, cooling, and reheating, and 3) determine the changes of SA, RFO, FOS, RS, and amylose concentration in different market classes of lentil, common bean, chickpea in response to four cooking temperature ranging from 90 to 120 ºC.
The first study results indicated that a 100 g of lentil, common bean, and chickpea had 12, 15, and 12 g of prebiotic carbohydrates respectively. Prebiotic carbohydrate concentrations within the pulse market classes were significantly different. The second study results showed that a 100 g of cooked common bean and chickpea provide 7 – 9 and 8 – 10 g of prebiotic carbohydrates respectively. Cooling and reheating reduced SA and RFO but increased FOS, RS, and amylose concentrations regardless of the pulse market classes. The third study results showed that increasing cooking temperature from 90 ºC to 120 ºC, increased SA, RFO, FOS, and amylose concentration but reduced RS concentration in pulse market classes. Overall, total prebiotic carbohydrates concentration was increased from 7 to 8 g/100 in lentil, 4 to 7 g/100 g in common bean, and 7 to 8 g/100 g in chickpea with increasing processing temperature.
In conclusion, prebiotic carbohydrate profiles are different in pulse market classes and it is possible to breed relevant pulse market classes with higher prebiotic carbohydrates. Further, processing methods change prebiotic carbohydrates concentration and therefore change the nutritional quality of pulses. Increasing cooking temperature up to 120 ºC increase prebiotic carbohydrates concentration in pulses. Thus, manipulation of processing conditions can be used to develop prebiotic carbohydrates rich pulse foods.
Siva, Niroshan, "Prebiotic Carbohydrate Profiles of Lentil, Chickpea, and Common Bean" (2019). All Dissertations. 2442.