literature review of food sensory evaluation
Sensory evaluation was undertaken to evaluate the micro-constituents of the soluble or insoluble dietary fibre systems, e.g. phenolic acids that could potentially promote the development of unpleasant flavours and therefore off-aromas. It is hypothesized that decarboxylation (removal of a carboxyl group with the of release carbon dioxide) of ferulic acid, a major phenolic acid found in oats, could produce polyvinyl guaiacol (PVG). PVG is a compound known to be responsible for off-flavours in food and can be produced during high temperature processing and subsequent prolonged storage of many food products containing insoluble dietary fibre. Therefore, the acceptability of UHT beverages containing either 5 or 10 % oat fibre stored at 22 and 40 °C, during a shelf life of up to 3 months was carried out by 8 semi-training sensory panellists using the smiling scale protocol. These are data are discussed in chapter four.
Sensory evaluation also performed on the fresh UHT samples at room temperature. It used a hedonic test with a 7-point scale in which a value of 1 referred to the statement “dislike very much” and 7 referred to the statement “like very much”. The seven attributes analysed in this work were the outcome of an earlier consultation with a wide consumer panel that used liquid breakfast products on a weekly basis. The factors they highlighted were smoothness, thickness, overall texture, colour, flavour, sweetness and overall acceptance. Statistical analysis on the data was conducted using one-way variance ANOVA for each attribute…………………………………………………………………..