RESUMO
The addition of edible fiber could affect the shelf life of cookies, which can have a positive or negative impact depending on the source of fiber. This study is in continuation of two previously published papers to investigate the storage stability of cookies incorporated with 4.5% beetroot leaf powder (BLP), with 7% sapota fiber powder (SFP) and reference cookies during 15 months at ambient temperature by analyses of physicochemical, microbial and sensory properties on each specified month using international standard methods. It was found that with increasing storage period, there was an increment in moisture content, peroxide value, free fatty acids and microbial population including total aerobic bacteria and yeast and mold colonies of all cookies; the lowest values being for cookies with 7% SFP (5.70%, 4.12 mEqO2/1000 g cookie's fat, 1.47%, 2.73 and 2.36 log CFU/g dried cookie, respectively). In contrast, the reverse trend was found in pH value. At the end of storage, a significant difference (p ≤ 0.05) was observed between reference cookies and other cookies regarding moisture content, peroxide value, free fatty acids and overall sensory acceptability; the quality of cookies supplemented with 7% SFP being desirable, followed by cookies with 4.5% BLP, and then reference cookies.
RESUMO
The aim of this study was to investigate the physicochemical, textural and organoleptic attributes of developed cookies containing concentrated chiku fiber powder (CChFP) (Manilkara zapota L.) at different levels (0, 4.5, 7, 9.5, 12%). The results revealed that the addition of CChFP led to a noticeable improvement in dietary fiber, crude fiber and antioxidant activity of cookies. However, the protein content and the hardness of cookies were decreased. The effect of added CChFP up to 7% in texture, taste and aroma of cookies was negligible. The cookie supplemented with 7% CChFP established a superior overall acceptability score among other cookies containing CChFP, with an improved crude fiber (3.41 ± 0.26%), total dietary fiber (14.03 ± 0.57%) and radical scavenging activity (6.20 ± 0.48%).
RESUMO
Arachidonic acid (ARA) and eicosapentaenoic acid (EPA) are important for human health and are produced by the fungus Mortierella alpina. Fermentation conditions may affect fatty acid profile of produced oil. Substrates in solid-state fermentation are usually renewable and low-cost agro-industrial waste. The aim of this research is to study simultaneous production of ARA and EPA by M. alpina CBS 528.72 in solid-state fermentation. Date waste and soybean meal served as carbon and nitrogen sources, respectively. Plackett-Burman design was used to evaluate the impact of eleven process variables on ARA and EPA production. Analysis of the results showed that the main variables with significant impact on production include seed age, and supplementation of linseed oil and nitrogen. These three variables were then studied in a central composite design for the optimization of production of both fatty acids. Finally, reconfirmation test was conducted to obtain experimental results from predicted optimum conditions. This report showed that simultaneous optimization of the production of ARA and EPA by M. alpina CBS 528.72 on date waste can be achieved by modification of process variables in solid-state fermentation.
RESUMO
This article reviews some of the aspects of single cell oil (SCO) production using solid-state fermentation (SSF) by fungi of the genus Mortierella. This article provides an overview of the advantages of SSF for SCO formation by the aforementioned fungus and demonstrates that the content of the polyunsaturated fatty acids (PUFA) depend on the type of fermentation media and culture conditions. Process variables that influence lipid accumulation by Mortierella spp. and the profile of the fatty acids are discussed, including incubation temperature, time, aeration, growth phase of the mycelium, particle size of the substrate, carbon to nitrogen ratio, initial moisture content and pH as well as supplementation of the substrate with nitrogen and oil. Finally, the article highlights future research trends for the scaled-up production of PUFAs in SSF.
