Effects of operating conditions on oil loss and structure of almond snacks

Novel Gluten-Free Breakfast Cereals Produced by Extrusion Cooking from Rice and Teff: Effects on Microstructural, Physical and Nutritional Properties

Current gluten-free products often have nutritional inadequacies. Teff is generating a growing interest for its excellent nutritional value. In this study, the effects of teff enrichment of extruded gluten-free breakfast cereals based on rice flour and two process parameters-feed moisture and temperature-were investigated based on their physical, microstructural and nutritional properties. The independent variables were modulated and examined by a Box-Behnken design. The incorporation of teff flour affected the sensory properties of extruded cereals, particularly lightness and crispness, with estimated linear effects of -6.91 and -8.49, respectively. The enrichment of breakfast cereals with teff flour also increased the total phenolic content and antioxidant capacity in both free and bound fractions, as well as the amount of insoluble dietary fibre. By varying all independent variables, the microstructural and physical properties of samples changed considerably. At the lowest feed moisture, wall thickness was small while showing the highest expansion. Samples with the highest teff flour addition exhibited an increased number of small pores which decreased crispness. These findings suggest that, by optimized extrusion cooking, the use of teff flour seems to be promising for the preparation of gluten-free breakfast cereals with superior nutritional properties and good structural characteristics.

Effect of soy flour addition and heat-processing method on nutritional quality and consumer acceptability of cassava complementary porridges

BACKGROUND

The nutritional quality of cassava complementary porridge was improved through extrusion cooking and compositing with either defatted or full fat soy flour (65:35 w/w), and product acceptability by mothers with children of the target population was evaluated.

RESULTS

The protein digestibility-corrected amino acid score (PDCAAS) of extrusion- and conventionally cooked composite porridges was within the recommendations for complementary foods. The kinetics of starch digestibility showed that all porridges had a rapid rate of starch digestibility, but the rate was lower when defatted soy flour was added and lowest when full fat soy flour was added. The formation of amylase-lipid complexes as shown by X-ray diffraction and differential scanning calorimetry can be attributed to the lower digestibility of extrusion-cooked porridge with full fat soy flour. If fed thrice per day, extrusion-cooked porridge with defatted or full fat soy flour would meet the energy, protein and available lysine requirements of a child aged 6-8 months receiving low or average nutrients from breast milk. All porridges were well received by Mozambican mothers who use cassava as a staple food. The mean scores for sensory liking of all porridges were 3 and above on a five-point hedonic scale.

CONCLUSION

Extrusion-cooked cassava/soy flour porridges have good potential for use as high-energy/high-protein complementary foods and have acceptable sensory properties.