Impact of high-pressure and microwave-assisted thermal pasteurization on inactivation of Listeria innocua and quality attributes of green beans

The cycloaddition strategy was employed in order to obtain a 7-oxanorbornene framework substituted with a guanidine moiety or its precursor functional groups: protected amine or thiourea. In order to optimize the conditions for the cycloaddition, several environmentally-friendly methods—microwave assisted organic synthesis, high pressure synthesis, high speed vibrational milling, and ultrasound assisted synthesis—were employed. The outcomes of the cycloaddition reactions were interpreted in terms of endo/exo selectivity, the conversion of the reactants to the product, and the isolated yields. In general, our results indicated the HP and HSVM approaches as the methods of choice to give good yields and conversions.

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Inactivation of Bacterial Pathogens in Human Milk by High-Pressure Processing†

Journal of Food Protection ◽

10.4315/0362-028x-71.1.109 ◽

2008 ◽

Vol 71 (1) ◽

pp. 109-118 ◽

Cited By ~ 39

Author(s):

S. VIAZIS ◽

B. E. FARKAS ◽

L. A. JAYKUS

Keyword(s):

High Pressure ◽

Human Milk ◽

Capillary Tube ◽

Bacterial Pathogens ◽

High Pressure Processing ◽

Viral Pathogens ◽

Promising Alternative ◽

Log Reduction ◽

Long Time ◽

Thermal Pasteurization

Low-temperature, long-time (LTLT) pasteurization assures the safety of banked human milk; however, heat can destroy important nutritional biomolecules. High-pressure processing (HPP) shows promise as an alternative for pasteurization of breast milk. The purpose of this study was to investigate the efficacy of HPP for inactivation of selected bacterial pathogens in human milk. Human milk was inoculated with one of five pathogens (108 to 109 CFU/ml), while 0.1% peptone solution solutions with the same levels of each organism were used as controls. The samples were subjected to 400 MPa at 21 to 31°C for 0 to 50 min or to 62.5°C for 0 to 30 min (capillary tube method) to simulate LTLT pasteurization. Tryptic soy agar and selective media were used for enumeration. Traditional thermal pasteurization resulted in inactivation (>7 log) of all pathogens within 10 min. In human milk and in peptone solution, a 6-log reduction was achieved after 30 min of HPP for Staphylococcus aureus ATCC 6538. After 30 min, S. aureus ATCC 25923 was reduced by 8 log and 6 log in human milk and peptone solution, respectively. Treatments of 4 and 7 min resulted in an 8-log inactivation of Streptococcus agalactiae ATCC 12927 in human milk and peptone solution, respectively, while Listeria monocytogenes ATCC 19115 required 2 min for an 8-log inactivation in human milk. Escherichia coli ATCC 25922 was inactivated by 8 log after 10 min in peptone solution and by 6 log after 30 min in human milk. These data suggest that HPP may be a promising alternative for pasteurization of human milk. Further research should evaluate the efficacy of HPP in the inactivation of relevant viral pathogens.

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Inactivation of Listeria monocytogenes and Listeria innocua in yogurt drink applying combination of high pressure processing and mint essential oils

Food Control ◽

10.1016/j.foodcont.2011.03.005 ◽

2011 ◽

Vol 22 (8) ◽

pp. 1435-1441 ◽

Cited By ~ 31

Author(s):

Gulsun Akdemir Evrendilek ◽

V.M. Balasubramaniam

Keyword(s):

High Pressure ◽

Listeria Monocytogenes ◽

Essential Oils ◽

High Pressure Processing ◽

Listeria Innocua ◽

Yogurt Drink

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A Chemometrics Approach Comparing Volatile Changes during the Shelf Life of Apple Juice Processed by Pulsed Electric Fields, High Pressure and Thermal Pasteurization

Foods ◽

10.3390/foods7100169 ◽

2018 ◽

Vol 7 (10) ◽

pp. 169 ◽

Cited By ~ 3

Author(s):

Biniam Kebede ◽

Pui Lee ◽

Sze Leong ◽

Vidya Kethireddy ◽

Qianli Ma ◽

...

Keyword(s):

High Pressure ◽

Shelf Life ◽

Electric Fields ◽

Pulsed Electric Fields ◽

High Pressure Processing ◽

Life Changes ◽

Processing Technologies ◽

Promotion Strategies ◽

Thermal Pasteurization ◽

Insight Into

High-Pressure Processing (HPP) and Pulsed Electric Fields (PEF) processing technologies are being used increasingly on a commercial basis, with high-quality labelled fruit juices being one of the most important promotion strategies. Quality-related enzymes, which might still be active after HPP and PEF pasteurization, can cause undesirable aroma changes during storage. This study investigated volatile changes during the shelf life of PEF (15.5 kV/cm and specific energy of 158 kJ/L), HPP (600 MPa for 3 min), and thermally (72 °C for 15 s) pasteurized Jazz apple juices—up to five weeks. To have an increased insight into the volatile changes, an integrated instrumental (GC-MS) and data analysis (chemometrics) approach was implemented. Immediately after pasteurization, PEF processing resulted a better retention of odor-active volatiles, such as (E)-2-hexenal and hexyl acetate, whereas thermal processing lowered their amount. During refrigerated storage, these volatiles have gradually decreased in all processed juices. By the end of storage, the amount of these aroma relevant volatiles appears to still be higher in PEF and HPP pasteurized juices compared to their conventional counterparts. This study demonstrated the potential of advanced chemometric approaches to obtain increased insight into complex shelf life changes.

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