Mediterranean countries are known for their high-quality olives and the production and consumption of olive oil. Olive pomace (OP), the major by-product of olive oil extraction, is receiving attention for its potential as a functional compound in food products, reflecting its physiology- and health-promoting attributes. This study assessed the physico-chemical characteristics of OP obtained from two Sardinian olive cultivars, Bosana and Semidana, and the effect of OP incorporation on the baking performance of wheat dough. We assessed the rheological parameters, pasting profile, and fermentation of doughs obtained through the partial substitution of wheat flour with OP at 0 (control), 1, 2, 3, and 5%. OP inclusion resulted in significant differences in the studied parameters compared with control samples. Positive effects included a decrease in development time, improved dough stability and storage, and superior loss modulus and gas retention capacity. Negative effects comprised an increase in dough resistance and a decrease in dough development height, gas production, gas retention, pasting profile, stickiness, and elasticity. These differences in the OP dough were due to the interactions between polyphenols and fibre with water and the starch–gluten matrix. This study found improvements in dough characteristics following the substitution of wheat flour with low percentages of OP, especially Semidana at 1%. Although higher percentages of OP would be associated with greater nutritional and health benefits, they resulted in a degradation of the dough’s attributes, producing a gluten-free-like matrix in the final product.
2 July 2024 in Frontiers in Sustainable Food Systems
In the last years, olive pomace, a by-product of olive oil extraction, has shown great interest. The work aims to valorize the olive pomace of two Sardinian olive cultivars, Bosana and Semidana, by incorporating them into the formulation of functional baked products to improve their nutritional value. The freeze-dried pomace of the two varieties has been used to substitute the type 00 flour in percentages of 1, 2, and 3% (w/w). The olive pomace was characterized by macro-composition analysis, while the bread samples were characterized for their proximate, physical, technological, sensory characteristics and shelf life. The specific volume of fortified samples decreased significantly compared to the control, while antioxidant activity, and nutritional parameters were significantly improved using olive pomace. Moreover, fortified samples showed a reduction of browning and whiteness indices with respect to control. Textural profile analysis showed a firmer product, compared to the control, with higher levels of olive pomace which also positively affected the cell size distribution in the crumb. Sensorially, consumers were mostly appealed by the 1% levels of substitution of olive pomace, in particular that of the Bosana. Hardness of all samples increased significantly along 7 days of storage thus resulting in a shelf life of less than 3 days. Therefore, it can be concluded that the incorporation of olive pomace, especially at low levels (1%), into white bread significantly improves the nutritional and sensorial quality of bread without significantly affecting its technological properties.
Red yeasts grow on food wastes, show antagonistic activity against food-spoilage microorganisms, produce food supplements, and may be utilized as feed-supplements themselves to positively modulate the quali-quantitative composition of intestinal microbiota. Therefore, they show a variety of possible biotechnological applications in agri-food-related processes. Here, to further explore the biotechnological potential of red yeasts, eleven strains ascribed to different species of the genera Rhodotorula and Sporobolomyces, differing for biomass and carotenoids production, were characterized in vitro for biofilm formation, invasive growth, and growth at the temperature range of 20–40 °C and in vivo for their antagonistic activity against the fungal pathogen and patulin producer Penicillium expansum. Most of them formed cellular MAT and showed invasive growth as well as adhesion to plastic materials. Four strains determined a significant reduction of fruit decay caused by P. expansum on apple fruit while the remaining seven showed different degrees of biocontrol activity. Finally, none of them grew at body temperature (>37 °C). Statistical analyses of both qualitative and quantitative phenotypic data, including biomass and carotenoids production, gathered further information on the most interesting strains for the biotechnological exploitation of red yeasts in agri-food-related process.
About Me
Microbiologist, PhD
Università degli Studi di Sassari
Dipartimento di Agraria
Scienze e tecnologie ambientali e alimentari
Microbiologist, PhD
Università degli Studi di Sassari
Dipartimento di Agraria
Scienze e tecnologie ambientali e alimentari