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The presence of several trace elements, heavy metals, and antimony in polyethylene terephthalate-bottled local raw cow milk samples of Iğdır region in Turkey was investigated. The milk samples were analyzed by inductively coupled plasma mass spectrometry after microwave-assisted digestion. Milk samples were categorized into three groups according to the element level intensity in the sample. While 70% of samples showed 2.5 times the maximum Turkish and European permissible level of lead, the lowest lead-contaminated sample exhibited 1.25 times this level. All the examined samples exceeded the maximum permissible limit administrated for arsenic and 35% of samples exhibited 5 times this limit. Results showed 40% of samples contain an antimony level higher than the Turkish maximum allowable concentration. The high antimony content of raw milk samples may be related to the release of antimony from the PET (polyethylene terephthalate) bottles. This study showed high contamination levels of the most toxic trace elements, i.e., lead and arsenic in milk and possible antimony contamination from PET bottles which may cause many health hazards for the consumers.

The use of gases in different food applications has increased in the last decades. The incorporation of hydrogen into yogurt was reported to improve the organoleptic properties of some dairy products. A study is needed to understand the effect of this application on the behavior of yogurt bacteria during the fermentation stage. The effects of H2- and N2-incorporation into milk on the acidification and reducing capacities of Lactobacillus delbrueckii subsp. bulgaricus (LB) and Streptococcus thermophilus (ST) were envisaged. A data acquisition multiparameter interface equipped with pH and redox electrodes was used for continuously measuring and recording values. H2 increased the acidification capacity of ST (+10%) and the reducing capacity of LB (+13.7%), whereas N2 increased the acidification capacity of ST (+13.3%) and decreased the reducing capacity of LB (-21.47%) and ST (-18.88%). H2 increased the coagulation time of LB (+12.96%) and ST (+6.15%). Results could reveal the promotive role of hydrogen on the metabolic activity of yogurt bacteria in single cultures and these bacteria grow better in the presence of hydrogen in milk. These results will allow yogurt manufacturers to better understand the behavior of yogurt bacterial strains when the preparation of gas-incorporated yogurt is envisaged and better control its quality attribute notes. [ABSTRACT FROM AUTHOR]

The acidification and reducing capacities of yoghurt bacteria were evaluated in different plant extract‐enriched milk samples. The milk samples enriched with thyme and grape seed extracts exhibited the highest values of acidification capacity for Lactobacillus delbrueckii subsp. bulgaricus (LB) (0.0065 pH unit/min) and Streptococcus thermophilus (ST) (0.0068 pH unit/min). The highest values of reducing capacity were observed in thyme (−0.98 mV/min), grape (−1.92 mV/min) and green tea (−0.75 mV/min)‐enriched samples for LB, ST and mixed culture of LB + ST, respectively. The fortification of yoghurt with plant extracts modified the acidification and reducing activities of starters, thus changing the fermentation time and quality attributes of the product. [ABSTRACT FROM AUTHOR]

[Display omitted] • HRW affected the profile of minerals, sugars, amino acids, and aroma of rice milk. • HRW rice milk showed a higher increase in some essential minerals. • HRW rice milk had higher levels of desirable aroma profile but not undesirable one. • HRW rice milk had higher levels of some essential amino acids. • Use of HRW enhanced the nutritional and sensorial quality of rice milk. The effect of using hydrogen-rich water (HRW) in the preparation of rice milk on the nutritional and sensorial properties was evaluated. The physicochemical parameters (pH, Eh7, titratable acidity), sensory properties (color), and minerals (ICP-MS), as well as amino acid (UPLC-ESI-MS/MS), sugar (HPLC-RID), and aroma (SPME–GC/MS) profiles, of four varieties of rice and their milk and waste were examined using Principal Component Analysis (PCA). Results showed that the profile of minerals, sugars, amino acids, and aroma was affected by the use of HRW. HRW-treated milk showed an increase in some essential minerals (Na, Mg, K, Ca, and Se) in some rice varieties. While HRW application enhanced the levels of desirable aroma compounds in milk but not the undesirable ones. This use of HRW allowed to increase in some essential amino acids (Ile, Leu, and Met) in HRW-treated rice milk samples. [ABSTRACT FROM AUTHOR]