Effect of addition of thermally modified cowpea protein on sensory acceptability and textural properties of wheat bread and sponge cake.
This paper investigates the sensory acceptability and textural properties of leavened wheat bread and sponge cake fortified with cow protein isolates that had been denatured and glycated by thermal treatment. Defatted cowpea flour was prepared from cow pea beans and the protein isolate was prepared (CPI) and thermally denatured (DCPI). To prepare glycated cowpea protein isolate (GCPI) the cowpea flour slurry was heat treated before isolation of the protein. CPI was more susceptible to thermal denaturation than GCPI as determined by turbidity and sulphydryl groups resulting in greater loss of solubility. This is attributed to the higher glycation degree and higher carbohydrate content of GCPI as demonstrated by glycoprotein staining of SDS PAGE gels. Water absorption of bread dough was significantly enhanced by DCPI and to a larger extent GCPI compared to the control, resulting in softer texture. CPI resulted in significantly increased crumb hardness in baked bread than the control whereas DCPI or GCPI resulted in significantly softer crumb. Bread fortified with 4% DCPI or GCPI was similar to control as regards sensory and textural properties whereas 4% CPI was significantly different, limiting its inclusion level to 2%. There was a trend for higher sensory acceptability scores for GCPI containing bread compared DCPI. Whole egg was replaced by 20% by GCPI (3.5%) in sponge cake without affecting the sensory acceptability, whereas CPI and DCPI supplemented cakes were significantly different than the control.
Implications of Blending Pulse and Wheat Flours on Rheology and Quality Characteristics of Baked Goods: A Review
Bread is one of the most widely consumed foods in all regions of the world. Wheat flour being its principal ingredient is a cereal crop low in protein. The protein content of a whole grain of wheat is about 12–15% and is deficit in some essential amino acids, for example, lysine. Conversely, the protein and fibre contents of legume crops are between 20 and 35% and 15 and 35%, respectively, depending on the type and cultivar of the legume. The importance of protein-rich diets for the growth and development of body organs and tissues as well as the overall functionality of the body is significant. Thus, in the last two decades, there has been a greater interest in the studies on the utilization of legumes in bread production and how the incorporation impacts the quality characteristics of the bread and the breadmaking process. The addition of plant-based protein flours has been shown to produce an improved quality characteristic, especially the nutritional quality aspect of bread. The objective of this review is to synthesize and critically investigate the body of research on the impact of adding legume flours on the rheological attributes of dough and the quality and baking characteristics of bread.
Application of resource allocation optimisation to provide profitable options for dairy production systems
A linear program (LP) model analysed resource use on a 100 ha dairy farm. A single optimum-profit combination was established for resources which were either optimised or constrained. It was found that, with a fixed herd of 320 milking cows, when production increased from 305 kg milksolids per cow (kg MS/cow) to 415 kg MS/cow, cash profit increased by 65%. This required additional supplements. If, however, feed demand and supply were optimised at 415 kg MS/cow, the LP reduced milking cow number rather than buy in feed to meet the increased feed demand from higher production per cow. At all production levels chosen between 305 and 415 kgMS/cow, it was most economic to dry off and cull cows early in dry summers to optimise feed demand vs. feed grown; use nitrogen (N) fertiliser to avoid a feed deficit only when response rates of better than 10 kgDM to 1 kg N could be expected; not use N for growing supplements to harvest. Pasture cover, within defined constraint levels, provided a buffer for feed demand and supply fluctuations. The study highlights the importance of assessing production, income and cost in an integrated framework to identify the point at which individual resources become limiting.