The suitability of South African flaxseed oilcake for inclusion in bread

M. Tech. Food Technology.Flaxseed oilcake as produced by a South African local Oil Mill has not been used directly in human food. The research problem was to evaluate the local flaxseed oilcake for its chemical and microbiological quality and shelf-life. Its suitability for incorporation into bread was investigated. Methods and procedures used included proximate analysis, determinations for total dietary fibre, fatty acid profile, mineral composition and water activity (aw); shelf-life studies and microbiological testing for spoilage micro-organisms and possible pathogenic bacteria. The effect of flaxseed oilcake inclusion in brown bread on the sensory quality of the bread was determined using a trained sensory panel and a consumer panel. A texture analyzer was used to measure the staling of the products. The main findings were that the flaxseed oilcake was high in protein and dietary fibre. The oil was rich in alpha linolenic acid. Toxic mineral content was such that it should be safe at suggested inclusion levels. The oilcake had a low microbial count and no pathogenic bacteria were found. The shelf-life study showed the oil to be relatively stable. Sensory analyses revealed that an 11% inclusion level of oilcake in brown bread was acceptable. In conclusion, it can be recommended that the locally produced oilcake is suitable for use in food and an 11% inclusion level will be safe and acceptable with nutritional benefits to the consumer