Nitrite-free implications on consumer acceptance and the behavior of pathogens in cured pork loins

Research Areas Food Science & TechnologyCured pork loins are valued products due to their particular sensory characteristics. These products are usually prepared with nitrite to guarantee adequate color and pathogen control. The use of nitrite in meat products has been criticized due to its potential contribution to carcinogenic N-nitroso-compound formation. The present work aimed to evaluate the effect of eliminating nitrite from the manufacturing of cured loins made with wine- and water-based marinades on the color evaluation of consumers and on the behavior of Clostridium sporogenes, Listeria monocytogenes, and Salmonella. The use of nitrite in processing cured loins resulted in a color considered adequate by more than 50% of the consumers. When nitrite was not used, the color was described mainly as weak. The hedonic evaluation of cured loins did not reflect the color evaluation. The samples with a weak and an adequate color had similar hedonic evaluations. The present work did not allow us to infer the potential interest in injecting S. xylosus into meat to prepare cured loins. The use of nitrite did not affect the survival of Cl. sporogenes, L. monocytogenes, or Salmonella. The reduction in the aw was the primary determinant influencing pathogen survival. The production of nitrite-free cured loins seems possible once the control of pathogens can be achieved. However, the product will have a weaker color. Consumers appreciate sensory aspects other than color, which, combined with the positive impact of the “additive-free” claim, can support the possibility of producing cured loins without nitriteinfo:eu-repo/semantics/publishedVersio

Sensory changes and listeria monocytogenes behavior in sliced cured pork loins during extended storage

Cured pork loins are sausages with a production tradition in several regions worldwide. They are made from one of the noblest cuts of pork, and for this reason cured loins are one of the most expensive pork meat products. Establishing the correct shelf life allows products to be accepted by the consumer, and to avoid the costs associated with shorter shelf lives. The aim of this study is: (1) to establish proper shelf life by evaluating the willingness of participants to consume and the sensory modifications that occur during prolonged storage via Check All That Apply (CATA) questions; and (2) to study the behavior of Listeria monocytogenes through a microbial challenge test. Sliced cured pork loins can be stored at 6 ± 1 °C for 105 days while maintaining a consumer acceptance of more than 75%. The freshness loss was associated mainly with a decrease in aromatic notes (particularly the smoke and cured aroma), and with the appearance of spoiled characteristics, specifically a sour/vinegar aroma and acidic taste that were detected by a reduced proportion of participants. The freshness evaluation was positively influenced by the typical characteristics of cured products, such as color and a garlic and wine aroma. Sour/vinegar aroma and acidic taste were the attributes most associated with higher freshness penalization. During the period of the test, Listeria monocytogenes inoculated onto the cured loin slices did not grow.FCT: GO77 PDR2020-1.0.1-FEADER-0313/ UIDB/CVT/00772/2020.info:eu-repo/semantics/publishedVersio

Constraints of HACCP Application on Edible Insect for Food and Feed

In a near future there is a need to guaranty food security for approximately more than one billion people worldwide. Beyond the population increase other factors contribute to food and feed insecurity such as climate changes, rising costs of animal protein and consumer demands for protein. Edible insects are pointed out as one alternative as they have always been a part of human diets. The concern to guaranty food security cannot be dissociated from food safety and under the Codex Alimentarius principles of food hygiene, insects would be comparable to other types of foods of animal origin. The processing and storage of insects and their products should follow the same health and sanitation regulations as for any other food or feed in order to ensure their microbiological and chemical safety. Allergies induced through insects’ ingestion should also be considered. This review aims to identify potential hazards related to edible insects’ production and transformation. Preventive measures to their control will be presented considering pre-requirements in their production and transformation. An HACCP plan will be described as a study case in insects’ transformation, being discussed all constraints regarding implementation

The risk of salt reduction in dry-cured sausage assessed by the influence on water activity and the survival of salmonella

Research Areas: Food Science & TechnologyWater activity (aw) is the main hurdle for microbial control in dry-cured sausages. The aw can be influenced by drying or adding electrolytes or humectants. Dry-cured meat products are partially dried, which, together with added salt, results in safe aw values. Currently, there is a trend to reduce salt in meat products, which can compromise the preservation process. The present work aims to evaluate the influences of added salt levels (1% or 3%) and the use or omission of phosphates and wine on the aw of a dry-cured sausage, and to evaluate the possibility of estimating the aw from the moisture loss and the behavior of Salmonella during dry-cured sausage (chouriço) processing. There was a strong relationship between moisture and aw, regardless of the salt level and the presence of phosphates or wine. Predicting aw from moisture loss is possible using the Boltzmann sigmoid function. The salt level strongly influences Salmonella behavior, mainly through aw reduction. An increase in aw by 0.01 units reduced the odds of achieving a 5-log reduction in Salmonella counts to half. Increasing added salt from 1% to 3% increased the odds of achieving a 5-log Salmonella reduction 7.5-fold. The current trend to reduce salt in foods must be carefully approached if applied to cured meat products, as it has substantial consequences on aw evolution and Salmonella survivalinfo:eu-repo/semantics/publishedVersio

Modelling the kinetics of Listeria monocytogenes in refrigerated fresh beef under different packaging atmospheres

The objective of this study was to model the fate of Listeria monocytogenes inoculated in beef at two concentrations (2.5 and 4.0 log CFU/g), packaged under air, vacuum and three modified atmospheres MAP: 70%O 2 /20%CO 2 /10%N 2 , 50%O 2 /40%CO 2 /10%N 2 and 30%O 2 /60%CO 2 /10%N 2 , and refrigerated at a normal temperature (4 °C) and at a mild abusive temperature (9 °C). The experimental design produced a total of 20 environmental conditions. An omnibus model based on the Weibull equation proved statistically that L. monocytogenes survives better in vacuum (VP) than in aerobic conditions, although without significant difference in its ability to survive in the temperature range between 4 °C and 9 °C. Furthermore, regardless of the refrigeration temperature, the presence of CO 2 in the package atmosphere exerted a bactericidal effect on L. monocytogenes cells, being approximately 1.5 log of reduction when storage time reached 10 days. Since the pathogen can survive in VP/MAP beef, there is a need of maintaining its numbers below 100 CFU/g before packaging by placing efforts on the implementation of control measures during processing.The authors would like to thank CECAV-UTAD and the research is supported by national funds by FCT- Portuguese Foundation for Science and Technology, under the PEst-OE/AGR/UI0772/2014. Dr. Gonzales–Barron wishes to acknowledge the financial support provided by the Portuguese Foundation for Science and Technology (FCT) through the award of a five-year Investigator Fellowship (IF) in the mode of Development Grants (IF/00570).info:eu-repo/semantics/publishedVersio

Effect of high hydrostatic pressure challenge on biogenic amines, microbiota, and sensory profile in traditional poultry- and pork-based semidried fermented sausage

Research Areas: Food Science & TechnologyThe processing of traditional poultry- and pork-based semidried fermented smoked sausages needs to bemodernized to improve product quality and further extend its shelf life. The aim of the present study was to applydifferent combinations of high pressure (300 to 600 MPa) and time (154 to 1,800 s) on the sausages using an experimentaldesign based on response surface methodology. The chemical, microbial, and sensory characteristics of sausages treatedwith high-pressure processing (HPP) were investigated. HPP application to semidried fermented sausages resulted incolor changes, which could be dependent on the ingredients, formulation, and smoking conditions used. Nevertheless,none of the HPP treatments applied resulted in detectable changes in sensory properties, as tested in a triangle test andconfirmed by the analysis of focus groups assessment. Significant differences were detected for lactic acid bacteria (LAB)counts from 344 MPa and 1,530 s onward, with a marked decrease for the combination of 600 MPa and 960 s (P<0.05).Coagulase-negativestaphylococcishowed higher tolerance to the increase in pressure than LAB. HPP induced a microbialreduction onEnterobacteriaceae, molds, and yeasts, minimizing the production of the main biogenic amines. However,the polyamines (spermine and spermidine) increased since their metabolic use by microorganisms did not occur. Giventhe reduction of the main spoilage microbial indicators with no detectable sensory changes observed with the binomialcondition of 600 MPa and 960 s, this was chosen as the optimal combination to be further applied.info:eu-repo/semantics/publishedVersio

Modelling the fate of Listeria Monocytogenes in Beef Meat Stored at Refrigeration Temperatures under Different Packaging Conditions

The objective of this study was to model the fate of L. monocytogenes inoculated in beef at two concentrations (2.5 and 4.0 log CFU/g), packaged under aerobic, vacuum and three modified atmosphere combinations – 70%O2/20%CO2/10%N2, 50%O2/40%C O2/10%N2 and 30%O2/60%CO2/10%N2, and refrigerated at a normal temperature (4ºC) and at a mild abuse temperature (9ºC). An omnibus model based on the three-parameter Weibull equation proved statistically that L. monocytogenes survives better in vacuum (VP) than in aerobic conditions, although without significant difference in its ability to survive in the temperature range between 4ºC and 9ºC. Furthermore, regardless of the refrigeration temperature, the presence of CO2 in package atmosphere exerted a bactericidal effect on L. monocytogenes cells, being approximately 1.5 log of reduction when storage time reached 10 days. Since the pathogen can survive in VP/MAP beef at refrigerated storage, there is a need of maintaining its numbers below 100 CFU/g before packaging by placing efforts on the implementation of control measures during processing.The authors would like to thank CECAV-UTAD and the research is supported by national funds by Portuguese Foundation for Science and Technology (FCT), under the PEst-OE/AGR/UI0772/2014. Dr. Gonzales-Barron wishes to acknowledge the financial support provided by the FCT through the award of a fiveyear Investigator Fellowship (IF) in the mode of Development Grants (IF/00570).info:eu-repo/semantics/publishedVersio

Multivariate nature of a cooked blood sausage spoilage along aerobic and vacuum package storage

Cooked blood sausages, such as Morcela de Arroz (MA), are ready-to-eat meat products consumed in many countries. The aim of this study was to demonstrate that spoilage of MA is multifactorial, involving microbiological, chemical and sensory modifications, which difficult the use of selected single indicators to establish product shelf life and to establish its shelf life based on consumers' willingness to consume. The experiment was conducted with samples without package (WP) and vacuum packaged (VP), stored at 4 +/- 1 degrees C. Quantitative descriptive analysis, Pseudomonas spp., lactic acid bacteria and Enterobacteriaceae counts, TBA-RS, total basic volatile nitrogen and lactic acid were determined and a consumer test was performed. Based on the consumer test, MA WP has a shelf life of 11.6 days and VP of 27.8 days. The multivariate approach showed a better predictive ability of consumer acceptability than single spoilage indicators.FCT, Fundacao para a Ciencia e a Tecnologia, PortugalPortuguese Foundation for Science and Technology [SFRH/BD/63341/2009]info:eu-repo/semantics/publishedVersio

Red Wine and Garlic as a Possible Alternative to Minimize the Use of Nitrite for Controlling Clostridium Sporogenes and Salmonella in a Cured Sausage: Safety and Sensory Implications

The use of nitrite in meat products has been questioned due to its potential association with colon cancer. This work aimed to evaluate the behavior of Clostridium sporogenes (used as a surrogate for Cl. botulinum) and Salmonella in a dry-cured sausage, chouri&ccedil;o, made with and without nitrite and nitrate or with red wine and garlic, and to study the sensory implications through a consumer test. The survival of Cl. sporogenes and Salmonella was determined mainly by the reduction in water activity (aw), but the use of wine or wine and garlic contributed to the control of Salmonella during processing. The challenge test with Cl. sporogenes revealed no effect of the curing salts, wine, or garlic on the population of this microorganism. The use of curing salts resulted in a more reddish color that was recognized by the consumer as over-cured and artificial when compared with chouri&ccedil;o made with wine or wine and garlic, which were better rated in the hedonic test. In cured sausages of small caliber, the use of nitrite might be reconsidered, as the values of aw necessary to inhibit Clostridium toxinogenesis and growth are achieved rapidly

Antimicrobial Properties of Chestnut Shell Extract as an Ecofriendly Approach for Food Preservation

The chestnut industry generates large quantities of by-products, including the chestnut shell, which is a source of phenolic compounds. In this study, the MIC (minimum inhibitory concentration) of chestnut shell extract was determined using the disk diffusion method. The chestnut shell was freeze-dried and milled. The extract was obtained using an ultrasound-assisted technique using water 70%: ethanol 30% (v/v) and subsequently lyophilized. Muller–Hinton plates were inoculated with ~105 CFU/mL of microorganisms. Sterile paper discs (6 mm) were placed on the inoculated culture medium and impregnated with 10 µL of each extract. Seven concentrations of extract between 0.3% and 2.1% were tested. The plates were incubated for 24 h at 37 °C. The antibacterial efficacy of the extracts was indicated by a halo formed around the paper disk. This work was carried out in triplicate. Halos were found at 1.5%, 1.8%, and 2.1% on Listeria monocytogenes ATCC 7973 (8.32 ± 0.06 mm for 2.1%), Enterococcus faecalis 19433 (8.94 ± 0.41 mm for 2.1%), and Staphylococcus aureus ATCC (10.26 ± 0.19 mm at 2.1%). For the remaining microorganisms, no halos were observed. The tested extract showed antimicrobial activity, demonstrating its potential for the control of pathogens in the food industry