scholarly journals Effects of Traditional Processing Techniques on the Nutritional and Microbiological Quality of Four Edible Insect Species Used for Food and Feed in East Africa

Foods ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 574 ◽  
Author(s):  
Dorothy N. Nyangena ◽  
Christopher Mutungi ◽  
Samuel Imathiu ◽  
John Kinyuru ◽  
Hippolyte Affognon ◽  
...  
Keyword(s):  
Microbiological Quality ◽  
Enteric Bacteria ◽  
Solar Drying ◽  
Bacterial Populations ◽  
Oven Drying ◽  
Edible Insect ◽  
Food And Feed ◽  
Traditional Processing ◽  
Processing Techniques

Edible insects are increasingly being considered as food and feed ingredients because of their rich nutrient content. Already, edible insect farming has taken-off in Africa, but quality and safety concerns call for simple, actionable hazard control mechanisms. We examined the effects of traditional processing techniques—boiling, toasting, solar-drying, oven-drying, boiling + oven-drying, boiling + solar-drying, toasting + oven-drying, toasting + solar-drying—on the proximate composition and microbiological quality of adult Acheta domesticus and Ruspolia differens, the prepupae of Hermetia illucens and 5th instar larvae of Spodoptera littoralis. Boiling, toasting, and drying decreased the dry matter crude fat by 0.8–51% in the order: toasting > boiling > oven-drying > solar-drying, whereas the protein contents increased by 1.2–22% following the same order. Boiling and toasting decreased aerobic mesophilic bacterial populations, lowered Staphylococcus aureus, and eliminated the yeasts and moulds, Lac+ enteric bacteria, and Salmonella. Oven-drying alone marginally lowered bacterial populations as well as yeast and moulds, whereas solar-drying alone had no effect on these parameters. Oven-drying of the boiled or toasted products increased the aerobic mesophilic bacteria counts but the products remained negative on Lac+ enteric bacteria and Salmonella. Traditional processing improves microbial safety but alters the nutritional value. Species- and treatment-specific patterns exist.

Impact of Raw Materials and Processing Techniques on The Microbiological Quality of Egyptian Domiati Cheese

2020 ◽  
Keyword(s):  
Raw Materials ◽  
Microbiological Quality ◽  
Raw Milk ◽  
Plate Count ◽  
E Coli ◽  
Fresh Cheese ◽  
Processing Techniques ◽  
The Impact ◽  
Total Yeast

Domiati cheese is the most popular brand of cheese ripened in brine in the Middle East in terms of consumed quantities. This study was performed to investigate the impact of the microbiological quality of the used raw materials, the applied traditional processing techniques and ripening period on the quality and safety of the produced cheese. Three hundred random composite samples were collected from three factories at Fayoum Governorate, Egypt. Collected samples represent twenty-five each of: raw milk, table salt, calf rennet, microbial rennet, water, environmental air, whey, fresh cheese, ripened cheese & swabs from: worker hands; cheese molds and utensils; tanks. All samples were examined microbiologically for Standard Plate Count (SPC), coliforms count, Staphylococcus aureus (S. aureus) count, total yeast & mould count, presence of E. coli, Salmonellae and Listeria monocytogenes (L. monocytogenes). The mean value of SPC, coliforms, S. aureus and total yeast & mould counts ranged from (79×102 CFU/m3 for air to 13×108 CFU/g for fresh cheese), (7×102 MPN/ cm2 for tank swabs to 80×106 MPN/ml for raw milk), (9×102 CFU/g for salt to 69×106 CFU/g for fresh cheese) and (2×102 CFU/cm2 for hand swabs to 60×104 CFU/g for fresh cheese), respectively. Whereas, E. coli, Salmonella and L. monocytogenes failed to be detected in all examined samples. There were significant differences in all determined microbiological parameters (p ≤0.05) between fresh and ripened cheese which may be attributed to different adverse conditions such as water activity, pH, salt content and temperature carried out to improve the quality of the product.

Microbiological Quality of Commercial Tofu

1984 ◽  
Vol 47 (3) ◽  
pp. 177-181 ◽  
Author(s):  
T. G. REHBERGER ◽  
L. A. WILSON ◽  
B. A. GLATZ
Keyword(s):  
Microbiological Quality ◽  
Plate Count ◽  
Microbial Counts ◽  
Colony Forming Units ◽  
Low Levels ◽  
Microbial Groups ◽  
Yeasts And Molds ◽  
Processing Techniques

A study was done to investigate the microbiological quality of commercial tofu available in local retail outlets. A sampling method was first developed to obtain accurate and representative microbial counts of individual pieces of tofu. Plate count determination of total aerobic organisms, psychrotrophs, coliforms, sporeformers, yeasts and molds, and staphylococci were made on 60 tofu samples (representing three lots each of four different brands) obtained within 24 h after delivery to the retail store. In addition, for two brands that provided manufacturer's pull dates, the same microbial counts were obtained for samples stored in the laboratory at 10°C until the pull date. Of the tofu sampled immediately after purchase, 83% of the lots tested had total counts greater than 106 colony-forming units (CFU)/g and psychrotrophic counts greater than 104 CFU/g. In addition, 67% of the lots tested had confirmed coliform counts greater than 103 CFU/g. Very low levels (less than 10 CFU/g) of all other microbial groups tested for were found in the majority of lots. Samples held until the manufacturer's pull date contained higher total and psychrotrophic counts but lower or stable counts of other organisms compared with samples tested immediately after purchase. To improve the microbiological quality of tofu, processors need to reduce initial loads by improving sanitation and processing techniques, and retailers should provide more consistent and colder refrigerated storage.

scholarly journals Low and High-Intensity Ultrasound in Dairy Products: Applications and Effects on Physicochemical and Microbiological Quality

Foods ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 1688
Author(s):  
América Chávez-Martínez ◽  
Raúl Alberto Reyes-Villagrana ◽  
Ana Luisa Rentería-Monterrubio ◽  
Rogelio Sánchez-Vega ◽  
Juan Manuel Tirado-Gallegos ◽  
...  
Keyword(s):  
High Intensity ◽  
Dairy Products ◽  
Microbiological Quality ◽  
Food Product ◽  
Raw Milk ◽  
Advantages And Disadvantages ◽  
Traditional Processing ◽  
Processing Techniques ◽  
Physical And Chemical ◽  
Milk And Dairy Products

Milk and dairy products have a major role in human nutrition, as they contribute essential nutrients for child development. The nutritional properties of dairy products are maintained despite applying traditional processing techniques. Nowadays, so-called emerging technologies have also been implemented for food manufacture and preservation purposes. Low- and high-intensity ultrasounds are among these technologies. Low-intensity ultrasounds have been used to determine, analyze and characterize the physical characteristics of foods, while high-intensity ultrasounds are applied to accelerate particular biological, physical and chemical processes during food product handling and transformation. The objective of this review is to explain the phenomenology of ultrasounds and to detail the differences between low and high-intensity ultrasounds, as well as to present the advantages and disadvantages of each one in terms of the processing, quality and preservation of milk and dairy products. Additionally, it reviews the rheological, physicochemical and microbiological applications in dairy products, such as raw milk, cream, yogurt, butter, ice cream and cheese. Finally, it explains some methodologies for the generation of emulsions, homogenates, crystallization, etc. Currently, low and high-intensity ultrasounds are an active field of study, and they might be promising tools in the dairy industry.

Changes in chemical and microbiological quality of semi-processed black soldier fly (Hermetia illucens L.) larval meal during storage

2020 ◽  
Vol 6 (4) ◽  
pp. 417-428
Author(s):  
E. Kamau ◽  
C. Mutungi ◽  
J. Kinyuru ◽  
S. Imathiu ◽  
H. Affognon ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Microbiological Quality ◽  
Colour Change ◽  
Salmonella Spp ◽  
Black Soldier Fly ◽  
Environment Temperature ◽  
Microbiological Parameters ◽  
Food And Feed ◽  
Processing And Storage

Edible insects are receiving attention as a protein source in the food and feed sector. However, successful commercialisation requires mass production matched with appropriate processing and storage techniques. The quality of dried and pulverised black soldier fly larvae stored in woven polypropylene (PP) sacks, polyethylene (PE) bags and plastic containers with screw lid (PL) in ambient and refrigerated environments was monitored over six months. Chemical indicators (oxidation, fatty acid profile), microbiological parameters (total viable counts, yeast and moulds, Enterobacteriaceae, presumptive coliforms, Salmonella) and colour change were examined. Temperature and relative humidity of the storage environments were monitored. In the ambient environment (temperature: 23.6±2.7 °C; relative humidity: 57.6±7.0%), chemical deterioration progressed 1.5 and 1.2 times faster in PP and PE, respectively, compared to PL. Refrigeration (temperature: 5.4±1.1 °C; relative humidity: 97±5.7%) exacerbated spoilage in the PP due to permeation of moisture through the woven strands, but slowed chemical deterioration by factors of 3.3 (PL) and 2.8 (PE). Likewise, based on the average counts of Enterobacteriaceae and yeast and moulds, microbiological deterioration progressed 2.1 and 1.4 times faster in the PP and PE, respectively, while refrigeration retarded build-up of microbial loads by factors of 1.3-9.6. The presence of Salmonella spp. in the experimental product indicates that due attention must be given to adequacy of processing and handling procedures for dried black soldier fly meal.

scholarly journals Elaboración Sostenible de Harina de Chile Jalapeño (Capsicum annuum L.) Mediante Secado Solar Tecnificado

2018 ◽  
Vol 14 (30) ◽  
pp. 15
Author(s):  
Gustavo Antonio Pech-González ◽  
Érika Guadalupe Ceballos-Falcón ◽  
Nicolás González-Cortés ◽  
Román Jiménez-Vera
Keyword(s):  
Capsicum Annuum ◽  
Microbiological Quality ◽  
Microbial Load ◽  
Human Consumption ◽  
Solar Drying ◽  
Drying Time ◽  
Capsicum Annuum L ◽  
Zinc Sheet ◽  
Protected Natural Areas

Jalapeño pepper (Capsicum annuum L.) is a crop in protected natural areas of Tabasco, Mexico. Solar drying is a non-polluting energy that is applicable to food processing. This paper focuses on comparing the microbiological quality of dehydrated jalapeño peppers by means of three methods: direct solar (SD), electric stove (EE), and experimental solar dryer (SSE). SD drying was carried out in zinc sheet by conduction. The drying in EE was at a temperature of 70°C and the SSE has an internal temperature of 43 ° C ± 2 ° C. The dehydrated chiles were crushed in artisanal equipment, and the flour was stored in tightly closed glass containers at room temperature (22-28 ° C). The drying time was lower in the EE (7 h), followed by the SSE (8 h) and the SD (18 h). With EE, the lowest microbial load was obtained and with SD, the highest was obtained. The flour obtained with the SSE presented a concentration of microorganisms within the Mexican norms: total coliforms (25 CFU / g), Staphylococcus aureus (62 CFU / g), and aerobic mesophiles (57 CFU / g). Although the drying time and the microbial load were lower with the EE, the SSE allowed the elaboration of jalapeño pepper flour with the microbiological quality required for human consumption. Technified solar drying is a sustainable alternative for the dehydration of foods in tropical countries.

scholarly journals Microbiological quality of feed materials used between 2009 and 2012 in Poland

2013 ◽  
Vol 57 (4) ◽  
pp. 535-543 ◽  
Author(s):  
Elżbieta Kukier ◽  
Magdalena Goldsztejn ◽  
Tomasz Grenda ◽  
Krzysztof Kwiatek ◽  
Łukasz Bocian
Keyword(s):  
Microbial Contamination ◽  
Microbiological Quality ◽  
Plate Count ◽  
Aerobic Bacteria ◽  
The Past ◽  
Total Plate Count ◽  
Food And Feed ◽  
Plate Counts ◽  
Materials Used

Abstract The study was conducted at all regional veterinary diagnostic laboratories. Feed materials were examined for Salmonella prevalence and contamination by Enterobacteriaceae, aerobic mesophilic bacteria, total plate count, fungi, Clostridium sp., and Bacillus cereus. Assays were done following international and Polish standards used in food and feed microbiology. Salmonella sp. were most often detected in oil seeds. In most of the examined feed ingredients, the number of Enterobacteriaceae did not exceed 10 cfu/g. The contamination by aerobic bacteria ranged most often from 101to 107 cfu/g, and the highest mycological contamination was noted in cereal grains (108 cfu/g). The results showed that microbial contamination of feed materials in regard to Enterobacteriaceae, fungi, and total plate counts declined over the past years.

The microbiological quality of beef tripe using different processing techniques

Meat Science ◽  
2002 ◽  
Vol 62 (1) ◽  
pp. 85-92 ◽  
Author(s):  
John C Bensink ◽  
Boris Dobrenov ◽  
Mwate P Mulenga ◽  
Zuhara S Bensink ◽  
Jeff J McKee
Keyword(s):  
Microbiological Quality ◽  
Processing Techniques

scholarly journals Biological contaminants in insects as food and feed

2021 ◽  
pp. 1-16
Author(s):  
D. Vandeweyer ◽  
J. De Smet ◽  
N. Van Looveren ◽  
L. Van Campenhout
Keyword(s):  
Foodborne Pathogens ◽  
Current Knowledge ◽  
Microbiological Quality ◽  
Edible Insects ◽  
Monitoring And Control ◽  
Microbiological Methods ◽  
Future Challenges ◽  
Biological Contaminants ◽  
Food And Feed

During the last decade, edible insects have successfully taken a meaningful position in the feed and food chain. To expand this position, product safety continuously needs to be warranted. This review focuses on the current knowledge and the future challenges on the prevalence of human foodborne pathogens in edible insects. The top three of the bacterial pathogens associated with insects for food are Staphylococcus aureus, pathogenic Clostridium spp. and pathogenic species of the Bacillus cereus group. Less is known about other types of biological contaminants, the fungi, viruses, protozoa and prions. For insects for feed, even less reports on pathogens are available so far, although the microbiota of Hermetia illucens is increasingly being studied in the latest years. In addition to the evaluation of endogenous microorganisms in insects, an overview is given of inoculation experiments to study the fate of specific food pathogens during rearing. Future challenges that are identified mainly relate to the fact that risk assessments directed to specific insect species are needed. Also, more research data are needed on the microbiological quality of substrates and residue, in connection with decontamination treatments. The house flora of rearing facilities has not been investigated before. The insect supply chain can generate insights in the microbiological quality of the integral chain by implementing exhaustive sampling plans and by applying predictive microbiology. Additionally, microbiological methods used in research and quality control require standardisation. Rather unexplored so far is the unculturable fraction of the insect microbial community and its importance in food safety. Last but not least, the most important microbiological challenge may well be situated in the further development of the sector: upscaling in terms of capacity and number of companies will increase the complexity of the sector. That will have implications for monitoring and control of biological contaminants.

scholarly journals Microbiological Changes in Smoked and Charred Baltic Herrings during Storage

1988 ◽  
Vol 51 (3) ◽  
pp. 197-200 ◽  
Author(s):  
HANNU J. KORKEALA ◽  
PEKKA K. PAKKALA
Keyword(s):  
Traditional Method ◽  
Bacterial Contamination ◽  
Microbiological Quality ◽  
Operating Line ◽  
Processing Plants ◽  
Plate Counts ◽  
The Mean ◽  
Traditional Processing ◽  
Better Than

The microbiological quality of smoked and charred Baltic herrings from two different processing plants was studied after preparation and after storage for 24, 48 and 96 h at 4 and 20°C. One of the processing plants used traditional processing methods and the other a modern processing technology. No significant increase in aerobic plate counts (APCs) was observed during storage of smoked herrings at 4°C; after 96 h the mean APC was 1.7 × 102 CFU/g. The mean APC of charred herrings increased markedly at 4°C within 48 h, and after 96 h was 2.4 × 104 CFU/g. At 20°C the mean APCs of smoked and charred herrings increased markedly within 24 h, and after 96 h were 1.0 × 108 and 1.7 × 109 CFU/g, respectively. At 20°C, high coliforms and fecal streptococci counts were found in some samples and high Staphylococcus aureus counts in 2 samples. The microbiological quality of smoked herrings was better than that of charred herrings both after processing and during storage. Bacterial numbers of smoked herrings prepared in a modern steel oven were lower than those of herrings prepared in a traditional tiled oven. The mean APC of charred herrings was, however, higher when the modern continuous-operating line was used compared to the traditional method. On the continuous-operating line, heavy bacterial contamination occurred during the salting stage. The salting procedure was therefore changed by cooling the brine. When chilled brine was used, the mean APC of charred herrings was lower than the corresponding mean for the traditional method.

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