The characterization of Listeria spp. isolated from food products and the food-processing environment

During processing of cereal-based food products, starch undergoes dramatic changes. The objective of this work was to evaluate the impact of food processing on the starch digestibility profile of cereal-based foods using advanced imaging techniques, and to determine the effect of preserving starch in its native, slowly digestible form on its in vivo metabolic fate. Four different food products using different processing technologies were evaluated: extruded products, rusks, soft-baked cakes, and rotary-molded biscuits. Imaging techniques (X-ray diffraction, micro-X-ray microtomography, and electronic microscopy) were used to investigate changes in slowly digestible starch (SDS) structure that occurred during these different food processing technologies. For in vivo evaluation, International Standards for glycemic index (GI) methodology were applied on 12 healthy subjects. Rotary molding preserved starch in its intact form and resulted in the highest SDS content (28 g/100 g) and a significantly lower glycemic and insulinemic response, while the three other technologies resulted in SDS contents below 3 g/100 g. These low SDS values were due to greater disruption of the starch structure, which translated to a shift from a crystalline structure to an amorphous one. Modulation of postprandial glycemia, through starch digestibility modulation, is a meaningful target for the prevention of metabolic diseases.

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Allergens from Edible Insects: Cross-reactivity and Effects of Processing

Current Allergy and Asthma Reports ◽

10.1007/s11882-021-01012-z ◽

2021 ◽

Vol 21 (5) ◽

Author(s):

Laura De Marchi ◽

Andrea Wangorsch ◽

Gianni Zoccatelli

Keyword(s):

Food Processing ◽

Cross Reactivity ◽

Allergic Reactions ◽

Edible Insects ◽

Insect Allergy ◽

Crucial Information ◽

Inhalant Allergens ◽

Minor Allergens

Abstract Purpose of Review The recent introduction of edible insects in Western countries has raised concerns about their safety in terms of allergenic reactions. The characterization of insect allergens, the sensitization and cross-reactivity mechanisms, and the effects of food processing represent crucial information for risk assessment. Recent Findings Allergic reactions to different insects and cross-reactivity with crustacean and inhalant allergens have been described, with the identification of new IgE-binding proteins besides well-known pan-allergens. Depending on the route of sensitization, different potential allergens seem to be involved. Food processing may affect the solubility and the immunoreactivity of insect allergens, with results depending on species and type of proteins. Chemical/enzymatic hydrolysis, in some cases, abolishes immunoreactivity. Summary More studies based on subjects with a confirmed insect allergy are necessary to identify major and minor allergens and the role of the route of sensitization. The effects of processing need to be further investigated to assess the risk associated with the ingestion of insect-containing food products.

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Flavor and Metabolite Profiles of Meat, Meat Substitutes, and Traditional Plant-Based High-Protein Food Products Available in Australia

Foods ◽

10.3390/foods10040801 ◽

2021 ◽

Vol 10 (4) ◽

pp. 801

Author(s):

Kornelia Kaczmarska ◽

Matthew Taylor ◽

Udayasika Piyasiri ◽

Damian Frank

Keyword(s):

Mass Spectrometry ◽

Solid Phase ◽

Food Products ◽

High Protein ◽

Gas Chromatography Mass Spectrometry ◽

Protein Food ◽

Volatile Flavor ◽

Orbitrap Mass Spectrometry ◽

Metabolite Profiles

Demand for plant-based proteins and plant-based food products is increasing globally. This trend is driven mainly by global population growth and a consumer shift towards more sustainable and healthier diets. Existing plant-based protein foods and meat mimetics often possess undesirable flavor and sensory properties and there is a need to better understand the formation of desirable meat-like flavors from plant precursors to improve acceptance of novel high-protein plant foods. This study aimed to comprehensively characterize the non-volatile flavor metabolites and the volatiles generated in grilled meat (beef, chicken, and pork) and compare these to commercially available meat substitutes and traditional high-protein plant-based foods (natto, tempeh, and tofu). Solid phase microextraction with gas-chromatography mass-spectrometry was used for elucidation of the flavor volatilome. Untargeted characterization of the non-volatile metabolome was conducted using Orbitrap mass spectrometry and Compound DiscovererTM datamining software. The study revealed greater diversity and higher concentrations of flavor volatiles in plant-based foods in comparison to grilled meat, although the odor activity of specific volatiles was not considered. On average, the total amount of volatiles in plant-based products were higher than in meat. A range of concentrations of free amino acids, dipeptide, tripeptides, tetrapeptides, nucleotides, flavonoids, and other metabolites was identified in meat and plant-based foods.

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Formulation and characterization of β-caryophellene-loaded lipid nanocarriers with different carrier lipids for food processing applications

LWT ◽

10.1016/j.lwt.2021.111805 ◽

2021 ◽

pp. 111805

Author(s):

Min Hyeock Lee ◽

In Young Lee ◽

Yong Gi Chun ◽

Bum-Keun Kim

Keyword(s):

Food Processing ◽

Lipid Nanocarriers

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Characterization of the Low-Salinity Stress in Vibrio vulnificus

Journal of Food Protection ◽

10.4315/0362-028x-71.2.416 ◽

2008 ◽

Vol 71 (2) ◽

pp. 416-419 ◽

Cited By ~ 18

Author(s):

HIN-CHUNG WONG ◽

SHU-HUI LIU

Keyword(s):

Salinity Stress ◽

Food Processing ◽

Vibrio Vulnificus ◽

Exponential Phase ◽

Salinity Adaptation ◽

Significant Protection ◽

Low Salinity ◽

Short Period ◽

Nonculturable State

Vibrio vulnificus is a marine pathogenic bacterium commonly found in seawater or seafood. This organism encounters low-salinity stress in its natural environment and during food processing. This study was designed to investigate the response of V. vulnificus YJ03 to lethal low salinity (0.04% NaCl) and its adaptation to sublethal salinity (0.12% NaCl with 20 amino acids added). A short period in the nonculturable state was induced by lethal low-salinity stress followed by cell death after 30 min of stress. Addition of 1 mM glycine betaine or 0.5 mM sucrose reduced the damage. Low-salinity adaptation was achieved in the exponential-phase cells but not in the stationary-phase cells. Significant protection against lethal low-salinity stress was attained when the cells were adapted for as little as 1.5 min. The adapted cells were significantly protected against lethal low salinity and 2.4% sodium sorbate but sensitized to the challenge of heat (52°C) and acid (pH 3.2). Nonlethal lowsalinity treatment of seafood should be avoided to prevent stress adaptation of V. vulnificus.

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