Digestibility and Nitrogen Balance in Rats Given Dried or Toasted Peas (Pisum sativum) of Different Years of Harvest

Experiments with Wistar rats were performed to study the digestibility of nutrients and nitrogen (N) utilization of dried and toasted (130°C, 3–4 min) peas (Pisum sativum spp hortense) cultivar Solara, harvested in two different years. Diets were formulated containing 111–128 g kg‐1 dietary fibre and ∽170 g kg‐1 crude protein with peas as the sole source of polysaccharides and N, and unsupplemented or supplemented with antibiotics (Nebacitin) to reduce the gastrointestinal microflora. In one of the harvests, the digestibility of starch was almost complete and unaffected by addition of Nebacitin. In the other harvest of peas, starch digestibility was very high (98·6–99·3%) in the rats with normal microflora, and reduced to 96% by addition of the antibiotics. The digestibility of non‐starch polysaccharides (NSP) was 71·2–72·8% in one harvest and 73·6–76·4% in the other. The digestibilities decreased by addition of Nebacitin (25·7–38·5%). Toasting affected the digestibility of some NSP monomers, but with different tendencies in the two harvests. The N metabolism was affected by toasting in one harvest, while there was no effect in the other. The effect of toasting on BV of peas and the availability of lysine were studied in one of the pea harvests. No effect was observed. © 1997 SCI.