SummaryProduction of wheat bran (WB) for human consumption is estimated to be about 90 million tonnes per year. WB is a cheap and abundant source of dietary fibre which has been linked to improved bowel health and possible prevention of some diseases such as colon cancer. It also contains minerals, vitamins and bioactive compounds such as phenolic acids, arabinoxylans, alkylresorcinol and phytosterols. These compounds have been suggested as an aid in prevention of noncommunicable diseases such as cardiovascular disease. This article discusses WB extraction, its nutritional properties, potential health benefits, effects on quality and sensory properties of some cereal foods, and its application in some baked products as well as in fried cereal snacks, as an additive for oil reduction and fibre enrichment.

The aim of this study was to determine the effect of size reduction of wheat bran (WB) on water holding capacity (WHC), water retention capacity (WRC), swelling capacity (SC); rheological and colour properties. Coarse WB exhibited the highest mean values for WHC (6.49 g/g), WRC (5.76 g/g), SC (7.67 g/g) and DHC (4.23 g/g), while these values were significantly reduced in fine WB. Size reduction increased lightness of WB as indicated by high L* values (62.65 to 75.80), Hue angle of 74.63 and whiteness index value of 81.42. Increasing WB additions increased water absorption of dough from 63 to 70.2%, while dough stability decreased from 12.5 min to 6.80 min. As coarse WB addition increased from 1 to 15 g extensibility decreased from 419 BU to 283 BU (highest level of addition). A negative correlation (r 2 = -0.992) was found between farinograph water absorption and all extensograph indices measured; implying that an increase in water absorption of dough led to a significant decrease in extensibility, maximum resistance and energy recorded for the dough. WB can be used as potential additive in foods like bread/ doughnut with the aim of optimizing their quality parameters such as nutritional and textural properties.Keywords: wheat bran; rheology; colour profile; hydration properties; mixing tolerance; particle size.Practical Application: Impact of size reduction of wheat bran on colour and rheological attributes is potentially applicable in development of existing and new cereal products.

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Fruits and vegetables are plant derived products which can be consumed in its raw form without undergoing processing or conversion. Fresh-cut fruits and vegetables (FFV) are products that have been cleaned, peeled, sliced, cubed or prepared for convenience or ready-to-eat consumption but remains in a living and respiring physiological condition. Methods of preserving FFV to retain its wholesomeness includes washing with hypochlorite, hydrogen peroxide, organic acids, warm water and ozone for disinfestation and sanitization; use of antimicrobial edible films and coatings; and controlled atmosphere storage and modified atmosphere packaging of fruits and vegetables. Exposure of intact or FFV to abiotic stress and some processing methods, induces biosynthesis of phenolic compounds and antioxidant capacity of the produce. Conversely, loss of vitamins and other nutrients has been reported during processing and storage of FFV, hence the need for appropriate processing techniques to retain their nutritional and organoleptic properties. FFV are still faced with the challenge of quality retention and shelf life preservation mostly during transportation and handling, without impacting on the microbiological safety of the product. Hence, food processors are continually investigating processes of retaining the nutritional, organoleptic and shelf stability of FFV.

The established use of wheat bran (WB) as a food ingredient is related to the nutritional components locked in its dietary fibre. Concurrently, the technological impairment it poses has impeded its use in product formulations. For over two decades, several modifications have been investigated to combat this problem. Ninety-three (93) studies (review and original research) published in English between January 1997 and April 2021 reporting WB modifications for improved nutritional, structural, and functional properties and prospective utilisation in food formulations were included in this paper. The modification methods include mechanical (milling), bioprocessing (enzymatic hydrolysis and fermentation with yeasts and bacteria), and thermal (dry heat, extrusion, autoclaving), treatments. This review condenses the current knowledge on the single and combined impact of various WB pre-treatments on its antioxidant profile, fibre solubilisation, hydration properties, microstructure, chemical properties, and technological properties. The use of modified WB in gluten-free, baked, and other food products was reviewed and possible gaps for future research are proposed. The application of modified WB will have broader application prospects in food formulations.

Oat bran (OB) and psyllium husk fibre (PF) were incorporated into magwinya (fat cake) – a cereal fried dough with the aim of reducing oil content and evaluating some of its physicochemical properties using one-factor of the response surface methodology. Two methods of magwinya processing were employed: traditional (TM) and modified (MM) methods. Addition of PF and OB significantly (p < 0.05) reduced oil in MM compared to TM. Lowest oil content for PF and OB magwinya were 3.10 and 4.35% using MM and 6.00 and 6.25% for TM. Addition of PF up to 3% and OB up to 2% significantly improved textural properties. Comparing the additives and the method of production, optimum conditions with highest desirability of 0.83 was obtained for OB modified magwinya with 35.08% moisture, 2.31% ash and 4.74% oil. Hence, the use of MM and OB reduced oil absorption.

The influence of fine and medium wheat bran (WB) particle sizes on process and quality parameters of a cereal fried dough (magwinya) was investigated. Magwinya is a snack that resembles, but different from doughnut and it is commonly consumed in most Sub-Saharan African countries. The effect of WB, fermentation and frying time was investigated on weight, diameter, volume, colour, hardness, fat, ash, and moisture, contents of magwinya. Further investigation on mineral and fibre contents as well as the consumer acceptance of optimised samples was also carried out. Predictive models were generated from responses with all lack of fit values >0.1, R2 values ≤0.99 and desirability function of 0.82 and 0.78 for fine and medium WB, respectively. Close agreement between experimental and predicted values for fat and ash was found. The linear, quadratic and interaction effects of process variables significantly (p < 0.05) increased ash, hardness, lightness and moisture and reduced volume and fat content of magwinya. incorporation of 15 g WB, dough fermentation time of 71.66 min (fine WB) and 76.43 min (medium WB) and 3 min frying time significantly (p < 0.05) reduced fat content of magwinya by 44.96% and 22.92%, respectively, and increased ash by 50.41% and 54.20%, respectively. Fine WB resulted in the least fat content while medium WB increased the ash and minerals.

This study investigated the effect of wheat bran (WB) supplementation on the physical and sensory properties of a South African cereal fried dough (magwinya). The physical properties, instrumental texture, and sensory profile were determined for magwinya (100:0, control) and for wheat flour to wheat-bran ratios of 95:5 (MWB5), 90:10 (MWB10), 85:15 (MWB15), and 80:20 (MWB20). An increase in the proportion of WB in the fried dough showed no significant difference on the specific volume (1.47–1.54) of samples. The chroma value (30.19–22.29), lightness (35.92–28.98), and hue angle (55.03–47.77) decreased, while ∆E increased distinctly with the addition of WB. Magwinya supplemented with WB was less cohesive and easy to chew. Significant correlations were found between instrumental hardness and sensory springiness (r = −0.63; p < 0.05), as well as between instrumental cohesiveness and sensory springiness (r = −0.71; p < 0.01). Two principal components were identified, which accounted for 85.1% of the variance in the instrumental data. A substitution level of 5 and 10% WB was similar to the sensory properties of the control in taste, texture, and overall acceptability and can replace part of the wheat flour in the cereal fried dough production.