The functional properties, gelation, water and oil absorption, emulsification, foaming and protein solubility of raw and heat processed cowpea flour were determined. The effects of pH and NaCl concentration on some of these functional properties were also investigated. Protein solubility vs pH profile showed minimal solubility at pH 4. Water and oil absorption capacities of raw flour were 2.4 g/g and 2.9 g/g, respectively, while heat processed flour gave 3.6 g/g and 3.2 gl g, respectively. Addition of NaCl up to 0.4% improved the emulsification capacity of raw flour while a decrease was observed in the heat processed flour after 0.2%. Least gelation concentration of raw flour was found to be 16% and heat processed flour, 18%.

The proximate composition and the functional properties of the flour of brown bean (Canal&& rosea DC) were investigated. Brown bean flour had 27.1 g/lOOg dry weight (DW) crude protein and 7.6 g/lOOg DW ether extractives. The brown bean flour had good water and oil absorption but poor gelation properties. Solubility of the brown bean protein was minimal at pH 4.0 but increased at pH 10. Foaming capacity of the flour could be improved by increasing concentration as well as by adding NaCl and was influenced by pH. Emulsion capacity was dependent on pH and salt concentration. Heat processing generally reduced the foamability and emulsification capacity of the brown bean flour.

I . Weanling rats were fed on purified-casein diets containing active and inactive (autoclaved) field bean (Mcia faba L.) proteinase inhibitors (PI) a t levels of 1.25, 25, 5.0 and 10 g/kg. Diets containing raw-and autoclaved-field-bean meal (FBM) were also given. The body-weight gain, protein efficiency ratio (PER); i.e. the ratio of the live weight gain in g/g of protein consumed and apparent nitrogen digestibility were determined 7, 14 and 21 d after the start of the trial. 2.Significant growth depression (P < o.001) was observed in rats given diets containing 2.5 g/kg PI (27-35 %). In rats fed on raw FBM growth depression was severe after 7 d (57 %). 3.Food intake was depressed at PI inclusion levels of 5 g/kg and higher between 14 and 21 d.4. PER was depressed significantly (33-44 %) in rats given diets containing the active PI a t all levels after 7 d. The protein utilization of all casein diets was higher than that of the FBM diets. 5.Apparent N digestibility was depressed in rats fed on diets containing 10 g/kg PI by 9 and 7 % at 14 and 21 d respectively. The N digestibility of both raw and heated FBM was similar a t approximately 84 %. (1973) showed that PI were responsible for 40 % of the growth depression observed when rats were fed on diets containing raw soya-bean meal. Raw FBM has also been found to depress growth of both rats and chicks (Sohonie et a/. 1958; Nitsan, 1971 ;Wilson & McNab, 1972;Marquardt & Campbell, 1973;Kadirvel & Clandinin, 1974) and PI have been implicated in this response.The work reported here was initiated to determine the nutritional and physiological significance of PI by means of incorporating the partially purified FBM inhibitors into diet devoid of other legume proteins. For comparison the nutritive value of FBM was also investigated to ascertain the importance if any, of PI and other anti-nutritional factors. MATERIALS A N D METHODS RatsMale weanling Wistar strain rats bred at the University of Nottingham School of Agriculture were used. The rats were distributed randomly, two per cage, in raised wire mesh bottom cages. A large metal tray covered with Whatman No. I filter paper which was changed daily was used to collect faeces and spilt food. Food pots were weighed daily and replenished.

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I . Male weanling rats were fed casein diets containing 1.25, 2.5, 5.0 and 10 g/kg active or autoclaved proteinase inhibitors (PI) from field bean (Viciu faba L.), and raw-and autoclaved-field-bean meal (FBM) diets. After 7, 14 and 2 1 d on the diets pancreas weights were measured and pancreas and intestinal trypsin (EC 3.4.4.4) and chymotrypsin (EC 3.4.4.5) assayed.2. Pancreas weights increased on the raw FBM and active-PI-supplemented diets. Maximum pancreatic hypertrophy measured as the percentage increase above controls was observed after 14 d in rats fed on raw FBM. The same percentage increase in pancreas size compared with appropriate controls was obtained with rats fed casein diets supplemented with 5 g active PI/kg.3. Pancreas trypsin and chymotrypsin levels decreased with increasing dietary PI level. Similarly, lower pancreas trypsin and chymotrypsin levels were observed in rats given raw FBM.4. Intestinal trypsin and chymotrypsin increased with increasing dietary PI inclusion level. Although the magnitude of this response decreased with the period of feeding the differences in enzyme levels were still significant even after 21 d.5 . It was concluded that the PI alone in raw-FBM diets could not entirely be responsible for theenlargement of the pancreas and the excess secretion of pancreatic enzymes since in synthetic diets PI levels of five times those in FBM were required to produce responses of similar magnitude.