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Progress in Agricultural Engineering Sciences
Authors:
Donald Bimpong
,
Lois Amponsah Adofowaa
,
Ama Agyeman
,
Abena Boakye
,
Ibok Nsa Oduro
,
Ellis William Otoo
, and
John-Lewis Zinia Zaukuu

Abstract

Peanut butter and yoghurt are targeted for adulteration intended at consumer deception. This study aimed to fingerprint and detect peanut butter and yoghurt adulteration with cassava flour and starch using Near Infrared Spectroscopy (NIRS) in a quasi-experimental approach. Ingredients for laboratory sample preparation were obtained from the Kumasi Metropolis. Peanut butter was adulterated at 1, 3, 5, 10, 15, 20% w/w and yoghurt at 0.25, 0.5, 1, 3, 5, 10, 15, 20, 25, 45, 50% w/w. Selected concentrations mimicked practices on the market. Marketed products were randomly sampled from six markets in the Kumasi Metropolis to validate the study models. Samples were scanned with a hand-held NIRS in triplicates. Chemometric (Principal Component Analysis (PCA), Linear Discriminant Analysis (LDA) and Partial Least Square Regression (PLSR) models) statistical methods were employed to develop classification and prediction models. Peaks with spectral bands such as 1050 , 1200 and 1450 nm were observed for peanut butter and 990–1100 nm, 1100–1200 nm and 1300–1408 nm were observed for yoghurt in the NIR spectrum. Some yoghurt brands were suspected of containing cassava starch, while Peanut butter from the different markets differed based on classification models. Cassava flour and starch concentrations were quantitatively predicted by PLSR with an R2 CV of 0.98 and an error of 0.9 g/100 g (low error).

Restricted access
European Journal of Microbiology and Immunology
Authors:
Ellis Kobina Paintsil
,
Wycliffe O. Masanta
,
Annika Dreyer
,
Leonid Ushanov
,
Stella I. Smith
,
Hagen Frickmann
, and
Andreas E. Zautner

Abstract

Campylobacter infections and campylobacteriosis-associated post-infectious sequelae are a significant global health burden that needs to be addressed from a specific African perspective. We conducted a comprehensive literature search on NCBI PubMed to compile a comprehensive narrative review article on Campylobacter infections in Africa, focusing on key aspects in human and veterinary medicine as well as food hygiene. We specifically focused on the epidemiology of enteropathogenic Campylobacter spp. in sub-Saharan and North Africa considering antimicrobial susceptibility. The most significant sequela resulting from molecular mimicry to Campylobacter surface structures is the Guillain-Barré syndrome, which was mainly examined in the context of limited studies conducted in African populations. A dedicated subsection is allocated to the limited research on the veterinary medically important species Campylobacter fetus. There are significant differences in the composition of the gut microbiome, especially in rural areas, which affect the colonization with Campylobacter spp. and the manifestation of campylobacteriosis. There may be a problem of overdiagnosis due to asymptomatic colonization, particularly in the detection of Campylobacter using molecular biological techniques. To reduce the colonization and infection rate of Campylobacter, we propose implementing several control measures and urge further research to improve the current understanding of the peculiarities of campylobacteriosis in Africa.

Open access

A talaj katabolikus aktivitás mintázatának elemzése mikrorespirációs (MicroResp) módszerrel

Analysis of soil catabolic activity patterns by micro-respiration (MicroResp)

Agrokémia és Talajtan
Authors:
Tibor Szili-Kovács
,
Márton Mucsi
,
Anna Füzy
,
Tünde Takács
, and
Andrea K. Borsodi

A talaj mikrobiális közösségének funkcionális diverzitása a talaj ökoszisztéma szolgáltatások jelentős részéhez hozzájárul, sok esetben meghatározó jelentőségű. Többféle kísérleti és elméleti megközelítés közül a katabolikus aktivitás-mintázat mikrorespirációs – MicroResp™ – módszerrel történő megközelítését mutatjuk be. A módszer a régebbről ismert szubsztrát-indukált respiráció több-szubsztrátos, mikrotiter lemez alapú kiterjesztése, amivel a talaj mikroba-közösség in-situ közösségi-szintű fiziológiai mintázata határozható meg. Mivel az egyes mikroorganizmusok szubsztrát-hasznosítása eltérő, a mikroba-közösség aktuális összetételétől, abundanciájától függően változó a szubsztrát hasznosítási mintázat egy-egy talajminta esetében. Az alkalmazott szubsztrátok köre tetszőleges, rendszerint egyszerű cukrok, aminosavak, aminok, karbonsavak. A módszer gyors, érzékeny, megbízható, ezért alkalmazása tervezett kísérletekben és talajmonitoring programokban egyaránt javasolható.

Open access

Abstract

Medication-related osteonecrosis of the jaw (MRONJ) is an increasingly common consequence of antiresorptive treatment, which often leads to the development of necrotic exposed bone surfaces with inflammatory processes affecting the jawbone. Although the development of MRONJ is often associated with the inflammatory response or infections caused by the colonizing members of the oral microbiota, the exact pathogenesis of MRONJ is still not fully understood. In the present paper, we aimed to provide additional, microbiological culture-supported evidence, supporting the “infection hypothesis” that Actinomyces spp. and related organisms may play an important pathogenic role in the development of MRONJ and the resulting bone necrosis. In our case series, all patients presented with similar underlying conditions and anamnestic data, and have received antiresorptive medications (bisphosphonates or a RANK ligand (RANKL) inhibitor) to prevent the occurrence or progression of bone metastases, secondary to prostate cancer. Nevertheless, a few years into antiresorptive drug therapy, varying stages of MRONJ was identified in the mentioned patients. In all three cases, quantitative microbiological culture of the necrotic bone samples yielded a complex microbiota, dominated by Actinomyces and Schaalia spp. with high colony counts. Additionally, our followed-up case series document the treatment of these patients with a combination of surgical intervention and long-term antibiotic therapy, where favourable clinical responses were seen is all cases. If the “infection hypothesis” is valid, it may have significant consequences in the preventative and therapeutic strategies associated with this disease.

Open access

Abstract

The soaking step of dry pulse products' – e.g. chickpeas' – food processing is a time consuming process. Soaking time can be significantly reduced by ultrasonic treatment or using higher processing temperatures. The effect of ultrasonic treatment can be investigated by examining the soaking water characteristics. Ultrasound-assisted soaking of chickpeas was performed at 25, 35 and 45 °C, respectively. Additionally, control samples were also prepared without ultrasonic treatment at the same temperatures. The dynamics of the fitted curve clearly shows the relationship namely the higher the treatment temperature, the faster the hydration of the raw material for both untreated and treated groups. In contrast to control group, swelling rate of 2.00 – except the group 45 °C – is not achieved during ultrasound-assisted soaking. In case of treated group, the swelling rate was about 1.90 for all temperatures applied. The ANOVA test shows that the color of the ultrasonically treated samples was significantly different compared to the control (F (5;12) = 207.86; P < 0.001). Average dry matter content and °Brix value were significantly higher in the ultrasound treated group compared to the control in case of all temperatures. This may indicate the destructive effect of ultrasound, which may cause more components to dissolve out of the raw material by the end of the soaking process.

Open access

Abstract

The objective of our work was to analyze the differences between four nut pastes, which were the following: walnut, peanut, pistachio, and tahini (sesame). The process technology of them is unknown, however, all the products contain 100% nut without any additives or flavoring.

The paste samples were measured at 25 ± 0.2 °C. The apparent viscosity at a 10 1/s shear rate during flow curve recording, and the dynamic viscosity at a constant 20 1/s shear rate was determined by viscosity measurement with the use of the MCR302 modular compact rheometer. The L*a*b* color components were determined by ColorLite sph850 spectrometer, finally, the particle sizes and shapes of the samples were analyzed by the high-speed image analysis instrument QICPIC.

The apparent viscosity and the average dynamic viscosity values of the four nut pastes were significantly different from each other. Differences were found between each paste according to the L*a*b* parameters. The complex structures of the particles are detailed and measurable, whereby the lengths and diameters of the particles can reliably be determined and fine deviations between the samples are detected. The sphericity decreases slightly with increasing particle size which means that bigger particles are more irregularly shaped.

Open access

Abstract

With growing attention to health and lifestyle changes, functional foods have become crucial and in demand. These foods are a rich source of probiotics and prebiotics, but most probiotic products are dairy-based, making them inappropriate for people with lactose intolerance or milk protein allergies. Nevertheless, egg white offers a viable substitute and is considered one of the best sources of functional proteins. As an alternative food matrix, they come highly recommended for those who are hypersensitive to dairy products or who follow a high-protein diet, such as athletes. In this context, egg-white drink with different carbohydrate sources, including monosaccharide (fructose) and oligosaccharide (fructooligosaccharide), was fermented by Lacticaseibacillus casei 01. After 24 h of fermentation, the total cell count was higher than 8 log10 CFU mL−1 thus, the egg white drink was suitable for L. casei 01 to grow. Additionally, the survival of L.casei 01, the pH value, and the rheological properties of fermented beverages within three weeks of refrigerated storage were also investigated. Throughout the storage period, the control samples exhibited considerably lower cell count and higher pH values compared to the samples with carbohydrate sources, also, samples containing the same carbohydrate source showed no noticeable changes. Viscosity measurements of the studied samples showed a shear thickening behaviour during the time.

Open access

Abstract

In recent years response surface analysis has been increasingly used to optimise membrane separation. It has many advantages, such as reducing the number of experiments to be performed, which requires lower energy consumption and significantly less laboratory work. For more accurate data analysis and forecasting, mathematical models are used that analyse the relevance of the factors examined and the interaction effects between the factors. In this research, two experimental designs that use response surface methodology are presented, namely, the central composite design and the Box–Behnken design. After the general characterisation of the experimental designs, their application in membrane technology is presented.

Open access

Abstract

Tomato (Solanum lycopersicum L.) is grown worldwide in open fields and greenhouses in a range of climate conditions. Hedgerows are a type of agroforestry systems that monitors ecological and influence microclimate conditions. An experiment was conducted at the Soroksár experimental field of the Hungarian University of Agriculture and Life Sciences in 2022 to investigate the influence of hedgerow technology on tomato plant leaves, N, P, K, chlorophyll, and carotene mineral levels from different distances, Exposed sides W1-3m, W2-9m and W3-15m and Protected sides NP1-3m, NP2-9m and NP3-15m, meters from the hedgerow trees.

The results investigate potassium and carotene, as well as chlorophyll b levels, are less differed among the protected and exposed side of the hedgerows trees, while the others were impacted to a certain extent; nitrogen and chlorophyll content was generally higher on the exposed side regardless of variety, while in the case of phosphorus adverse effects were observed. Distance from the hedge showed similar patterns for all traits. The results will help to better understand the impact of alternate technologies on tomato production in open-field conditions.

Open access

Abstract

Polyphenols from agro-industrial waste particularly of fruit origin are a reliable source of antioxidants and antimicrobials that can be used as natural food additives. Organic solvents play an important role in extracting the polyphenols, however, inefficiency in exerting bioactivity and interference with the organoleptic properties are among the reasons that hinder their use as food additives. These problems can be alleviated by purification. In this study, the effect of resin types and elution solvent for purification of the apple pomace extracts on total phenolic content (TPC) and antioxidants were investigated. Crude ethanolic extracts were purified using amberlite resins (XAD7HP and FPX66) in a glass column (25 × 310 mm). The sorption flow rate was 2 Bed volume (BV) per hour, rinse 2 BV per hour, and desorption was 2 BV per hour. Final wash and regeneration were each done by 2 BV per hour. Polyphenol content and antioxidant capacity were quantified spectrophotometrically using Folin-Ciocalteu and Ferric reducing ability of plasma (FRAP) assays respectively. Polyphenol recovery was 50% in XAD7HP (Lowest) using ethanol and 69% in FPX66 (Highest) using acetone. For the case of FRAP recovery, 76% (Lowest) was observed in FPX66 using ethanol while 93% (Highest) was observed in XAD7HP using acetone. Conclusively, FPX66 is the ideal resin for the purification of apple pomace extracts for enhancing antioxidant activity compared to XAD7HP. Further, acetone seems to be a good desorption solvent compared to ethanol.

Open access