In the context of current global challenges in wheat production with declining grain protein contents, the aim has been to investigate the use of low protein wheat flour in the processing of instant Asian noodles. For this study, Australian Soft (AS) flour was selected as it is of low protein content and low gluten strength and for comparative purposes, a high protein flour (Baker’s) was used as a control to reflect current commercial practice. A preliminary investigation was carried out to compare commercial instant noodles and samples prepared under laboratory conditions. The noodles made from AS flour had acceptable but slightly higher hardness and stickiness values, less appealing appearance as well as higher fat uptakes compared to a series of commercial instant noodles. Several ingredients were added into the noodle formulation in order to enhance the quality of instant noodles made from AS flour. The ingredients selected were the enzyme microbial transglutaminase (MTGase), emulsifier (sodium stearoyl lactylate, SSL), modified starch (acetylated potato starch, APS) and gum (sodium carboxymethyl cellulose, CMC). The addition of the ingredients enhanced the textural properties of noodles prepared from AS flour. Electron microscopy confirmed the enhanced development of structure within the noodles when MTGase and SSL were incorporated. In terms of colour, marginal visual difference was observed when combinations of APS and CMC were used, with samples showing a slightly dull appearance compared with the control. An inverse relationship was found between fat uptake and the incorporation of MTGase, water and APS. The impact of varying conditions during instant noodle processing was also studied, particularly mixing, resting, number of folds and the parameters of frying. The combination of mixing and resting time had a major impact on hardness while the yellowness ( b * value) of the product was enhanced when the mixing time and frying temperature were increased. Combinations of short frying times and low frying temperatures produced noodles with lower fat contents. The feasibility of incorporating common buckwheat (Fagopyrum esculentum Moench) into instant noodle formulations to improve the antioxidant properties was investigated. With increased addition of buckwheat flour, noodles made using AS flour produced softer texture. Furthermore whiteness ( L * values) decreased and fat uptake was marginally affected. The levels of the antioxidant rutin were measured in the noodles and were found to increase when additional buckwheat flour was added although losses did occur during the last stage of processing. The results of these trials show that various options are available which will enhance the quality attributes of instant Asian noodles made from AS flour. Product formulation and processing variables can be manipulated to enhance texture and colour appeal as well as reduce fat uptake. Common buckwheat flour can also be incorporated at moderate levels. In summary, these findings provide strategies for utilising low protein flour (AS) for making instant noodles. The results represent a sound scientific basis upon which processors can modify noodle formulations or vary processing conditions in order to meet the preferences of particular consumers for instant Asian noodles.
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