Biochemical Properties Affecting the Nutritional Quality, Safety, and Aroma of Dry-Cured Products Manufactured from Meat of Rare Native Pig Breeds.

The aim of study was to compare the biochemical properties affecting the nutritional quality, safety, and aroma of dry-cured products manufactured from valuable meat of rare native pig breeds: Pulawska (Pul) and Zlotnicka Spotted (ZS). The count of lactic acid bacteria (4.4 log cfu/g) and the release of palmitic (23.1% and 25.9%), oleic (44.1% and 42.2%), and linoleic acids (8.3% and 7.8%), as well as arginine (30.0 and 44.3 mg/kg), histidine (25.8 and 20.6 mg/kg), and lysine (26.8-22.9 mg/kg), shaped the final pH (5.3 and 5.4) in Pul and ZS products during the 4 week maturing, respectively. Lastly, Pul and ZS meat differed in the proportion of decanoic, lauric, stearic, arachidic, and conjugated linoleic acids. The high content of putrescine (23.7 mg/kg), cadaverine (54.3 mg/kg), and tyramine (57.2 mg/kg), as well as a twofold greater share of histamine (163.2 mg/kg) and tryptamine (9.1 mg/kg), indicated a more advanced decarboxylation of ZS meat. Volatile compounds differentiating Pul and ZS meat were primarily hexanal, 3-hydroxybutan-2-one, phenylacetalaldehyde, 2,3-dimethyl-2-cyclopenten-1-one, 2-cyclopenten-1-one, and 3-methyl- and 2-cyclopenten-1-one. Most marked volatile compounds were obtained as a result of microbial activity (acetic acid, 3-methylbutan-1-ol, ethanol, acetone, and 3-hydroxybutan-2-one), advanced lipid oxidation, and decomposition of secondary oxidation products (hexanal, phenylacetaldehyde, and 2-cyclopenten-1-one).

Changes in the physicochemical properties of barley and oat starches upon the use of environmentally friendly oxidation methods.

In this work, two environmentally friendly modification methods, UV irradiation and thermal treatment, were applied for the first time for modifications of oat and barley starches. Their impacts on starch properties were compared with those observed for starch oxidation with NaClO. XRD, EPR, FTIR, SEM and SEC methods were used to characterize the effects of modifications on starch structures. The decreases in molecular weight and crystallinity degree showed the destruction of starch structures upon prolonged UV irradiation and thermal treatment, more advanced in barley starch. The process of radical formation, studied by EPR, occurring to a larger extent in this starch, confirmed lower stability of barley starch structure. The alterations of starch structures correlated well with changes in its functional properties. It was found that UV irradiation was an effective oxidizing agent, whereas heating led mainly to the depolymerization of starch chains.