Improvement of Quality Properties and Shelf Life Stability of New Formulated Muffins Based on Black Rice.

Effects of partial (50%) and total replacement of wheat flour with black rice flour on the phytochemical, physico-chemical, sensorial, and textural properties of muffins were studied. Partial or total replacement of wheat flour with black rice flour in muffins improved their nutritional and antioxidative properties with a positive effect on microbiological and color stability during the storage period in accelerated conditions. The low gluten muffins had an anthocyanin content of 27.54 ± 2.22 mg cyanidin-3-glucoside (C3G)/100 g dry weight (DW), whereas the gluten free muffins had 46.11 ± 3.91 mg C3G/100 g DW, with significant antioxidant values. Retention of 60% and 64% for anthocyanins and 72% and 80% for antioxidant activity after baking was found. The fracturability and hardness scores increased with the addition of black rice flour, whereas firmness and chewiness increased for gluten free muffins. The confocal analysis revealed a tendency of glucidic components to aggregate, with gathers of small bunches of black rice starch granules comprising anthocyanin. The results allowed designing two new value added bakery products, low and free gluten muffins, with significant high amounts of bioactive compounds, suggesting the functional potential of black rice flour.

Synthesis and in vitro antimicrobial evaluation of new N-heterocyclic diquaternary pyridinium compounds.

A series of bis-pyridinium quaternary ammonium salts (bis-PyQAs) with different aryl and heteroaryl moieties were synthesized and their antimicrobial activity investigated. The inhibition effect of the compounds was evaluated against bacteria, molds and yeasts; the activities were expressed as the minimum inhibitory concentrations (MIC). The relationships between the structure descriptors (logP, polarizability, polar surface area (2D), van der Waals area (3D)) and the biological activity of the tested bis-PyQAs are discussed.

Production of medium chain saturated fatty acids with enhanced antimicrobial activity from crude coconut fat by solid state cultivation of Yarrowia lipolytica.

Fatty acids profiles and antimicrobial activity of crude coconut fat hydrolysates obtained in solid-state cultivation system with a selected yeast strain Yarrowia lipolytica RO13 were performed. A preliminary step regarding extracellular lipase production and solid state enzymatic hydrolysis of crude fat at different water activity and time intervals up to 7 days was also applied. Gas chromatography-mass spectrometry analysis was used for quantification of medium chain saturated fatty acids (MCSFAs) and the results revealed a higher concentration of about 70% lauric acid from total fatty acids. Further, antimicrobial activity of fatty acids against some food-borne pathogens (Salmonella enteritidis, Escherichia coli, Listeria monocytogenes and Bacillus cereus) was evaluated. The minimum inhibitory concentration of the obtained hydrolysates varied from 12.5 to 1.56 ppm, significantly lower than values reported in literature. The results provide substantial evidence for obtaining biopreservative effects by coconut fat enzymatic hydrolysis.