Impact of Ohmic Heating and High Pressure Processing on Qualitative Attributes of Ohmic Treated Peach Cubes in Syrup

Study on the Mechanisms of Flavor Compound Changes During the Lactic Fermentation Process of Peach and Apricot Mixed Juice

This study employed headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) and liquid chromatography-mass spectrometry (LC-MS) for non-targeted metabolomics analyses to examine the impact of mixed fermentation with various lactic acid bacteria (LAB) on the flavor compounds and metabolites of peach and apricot mixed juice (PAMJ), specifically focusing on the alterations of volatile compounds and non-volatile metabolites, as well as their metabolic pathways during the fermentation process. A total of 185 volatiles were identified using HS-SPME-GC-MS analysis, revealing significant differential metabolites, including eugenol, benzaldehyde, and γ-decalactone etc. The results indicated that lactic fermentation significantly enhanced the overall flavor of the juice toward the end of the fermentation process. In the interim, untargeted metabolomics utilizing LC-MS identified 1846 divergent metabolites, with 564 exhibiting up-regulation and 1282 demonstrating down-regulation. The metabolic pathway study performed by the Kyoto Encyclopedia of Genes and Genomes (KEGG) revealed significant changes in the metabolic levels of amino acids and saccharides after the lactic fermentation of PAMJ. Primarily associated with amino acid metabolism and starch and sucrose metabolism pathways. This work establishes a theoretical foundation for advancing fermented fruit juices with superior quality.

A bibliometric analysis of ohmic heating on food processing in the last two decades

Novel food processing technologies have been devised to cater to the specific requirements of consumer products and tackle the challenges associated with conventional food processing technologies. Ohmic heating is a contemporary thermal-process technology with advantages for time efficiency, improved sensory and functional quality, and enhanced energy efficiency. This bibliometric investigation aimed to analyze the level of scholarly research on ohmic heating within the field of food research over the past twenty years (2003-2023). The findings indicate an upward annual growth rate of 11.09 % in the subject of food-related ohmic heating research. A total of 769 publications have been published, involving 1841 authors. Brazil is recognized as the nation with the most research contributions while Sastry, S.K., is the most productive author, and Teixeira, J.A. is the most collaborative author. Review studies examining the impact of ohmic processes on the nutritional composition of fruits, vegetables, and grains have garnered the highest number of citations. Innovative Food Science and Emerging Technologies and the Journal of Food Engineering have emerged as the most influential journals in this field. Keywords such as "ohmic heating," "electroconductive heating," and "joule heating" are commonly used in academic publications on the application of ohmic heating in the food industry. Recent trends in this field focus on aspects such as extraction procedures, pasteurization, physicochemical components, and energy usage. Ohmic heating has a bright future. Rapidly growing research shows strong interest, especially recently, because of attractive advantages such as energy efficiency and sustainability. International collaborations will expand its applications in the food industry. Challenges include high capital costs, maintenance, and unclear regulations. Future research should focus on cost-effective materials, thermal stability, food safety, and broader applications. With a clear path, the food industry can adopt ohmic heating technology as affordable and ecofriendly technology more efficiently.

Impact of High-Pressure Processing on Antioxidant Activity during Storage of Fruits and Fruit Products: A Review

Fruits and fruit products are an essential part of the human diet. Their health benefits are directly related to their content of valuable bioactive compounds, such as polyphenols, anthocyanins, or vitamins. Heat treatments allow the production of stable and safe products; however, their sensory quality and chemical composition are subject to significant negative changes. The use of emerging non-thermal technologies, such as HPP (High Pressure Processing), has the potential to inactivate the microbial load while exerting minimal effects on the nutritional and organoleptic properties of food products. HPP is an adequate alternative to heat treatments and simultaneously achieves the purposes of preservation and maintenance of freshness characteristics and health benefits of the final products. However, compounds responsible for antioxidant activity can be significantly affected during treatment and storage of HPP-processed products. Therefore, this article reviews the effect of HPP treatment and subsequent storage on the antioxidant activity (oxygen radical absorbance capacity (ORAC) assay), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity assay, ferric reducing antioxidant power (FRAP) assay, 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging capacity assay or Trolox equivalent antioxidant capacity (TEAC) assay), and on the total phenolic, flavonoid, carotenoid, anthocyanin and vitamin contents of fruits and different processed fruit-based products.

Ohmic heating increases inactivation and morphological changes of Salmonella sp. and the formation of bioactive compounds in infant formula

The effect of ohmic heating (OH) (50, 55, and 60 °C, 6 V/cm) on the inactivation kinetics (Weibull model) and morphological changes (scanning electron microscopy and flow cytometry) of Salmonella spp. in infant formula (IF) was evaluated. In addition, thermal load indicators (hydroxymethylfurfural and whey protein nitrogen index, HMF, and WPNI) and bioactive compounds (DPPH, total phenolics, ACE, α-amylase, and α-glucosidase inhibitory activities) were also studied. OH presented a more intense inactivation rate than conventional heating, resulting in a reduction of about 5 log CFU per mL at 60 °C in only 2.91 min, being also noted a greater cell membrane deformation, higher formation of bioactive compounds, and lower values for the thermal load parameters. Overall, OH contributed to retaining the nutritional value and improve food safety in IF processing.