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Abstract

This study aimed to assess the effectiveness of two reverse osmosis membranes (RO99 and X20) plus one nanofiltration membrane (NF270) at concentrating hawthorn fruit and anise seed extracts. Extracting the anise was done using water at a temperature of 37 °C over a period of 100 min. For hawthorn, ethanol-water (56%) was used as the solvent and extraction occurred at 55 °C for 80 min. The transmembrane pressure (TMP), temperature, and recirculation flow rate of the membrane separation process were monitored and set at 35 bar, 30 °C, and 400 l/h respectively. Using a spectrophotometer, the quantification of valuable compounds was examined. After studying the flow levels, it was discovered that the X20 membrane had the tiniest alterations in permeability, followed by RO99 and NF270. Moreover, in terms of efficiency, the X-20 outperformed RO-99 and NF-270 membranes, where TPC was increased (20 and 18-fold) for anise seed and hawthorn fruit extracts respectively, and TFC was increased 8-fold for both of the extracts. While using NF-270, TPC was increased only (11 and 6-fold), and TFC (4 and 2-fold) for anise seed and hawthorn fruit extracts respectively. For the antioxidant activity, the process using X-20 showed an improvement of around 12-fold for anise extracts and 15-fold for hawthorn extracts for antioxidant activity. In terms of brix, the anise extracts saw a 3-fold increase and the hawthorn extracts saw a 4-fold boost after going through the X-20 membrane concentration process. Additionally, the X-20 membrane exhibits the highest retention rates for both anise and hawthorn extracts and is least affected by fouling during the concentration process.

Open access

Abstract

The food robotics revolution is driving a shift in the vending machine sector from conventional pre-packaged sales to on-site food manufacture. As these machines develop into small-scale food processing points, it is critical to guarantee food safety. The implementation of automated Clean-in-Place (CIP) techniques, in addition to manual cleaning, is modelled after food production practices, where hygiene is maintained without direct human intervention. These days, running these modern, multifunctional vending machines requires giving the highest priority to food safety and putting rigorous control measures in practice.

This case study aimed to implement a CIP procedure in a vending machine and assess microbial contamination. Water, blender, and smoothies were microbiologically analyzed to evaluate the microbial safety of ingredients, equipment, and the final product.

Microbiological analysis showed that none of the samples was contaminated with three major pathogens: Listeria monocytogenes, Salmonella spp., and Escherichia coli. This study showed the importance of the Clean-in-Place (CIP) process in automated vending machines.

Open access

Abstract

The aim of the present study was to find the best extraction parameters to obtain the highest amounts of polyphenols and antioxidants from the walnut. Walnut kernels from ‘Alsószentiváni 117’ cultivar were used for extraction. The extraction methods were as the follows:

Method 1: shaking water-bath at 50 °C for 30 min.

Method 2: shaking water-bath at 50 °C for 30 min, then storing at 5 °C for 20 h.

Method 3: shaking water-bath at 40 °C for 30 min.

Method 4: shaking water-bath at 40 °C for 30 min, then storing at 5 °C for 20 h.

According to our results Method 1 showed the highest FRAP value (34.43 mg AAE g−1), the DPPH value (52,94%) and the highest HPLC peaks for chlorogenic acid, epicatechin and rutin were also seen in extracts obtained using Method 1. TPC values of Method 3 were 26.06 mg GAE g−1 for Method 1 it was 25.65 mg GAE g−1. The results of color values, L* and ΔE* were similar in all extracts as well. In our experiments extraction Method 1 proved to be better than others.

Open access
Progress in Agricultural Engineering Sciences
Authors:
Zsuzsanna Horváth-Mezőfi
,
Emese Bátor
,
Gergő Szabó
,
Mónika Göb
,
Zoltán Sasvár
,
Lien Le Phuong Nguyen
,
Koppány Majzinger
,
Karina Ilona Hidas
,
Anna Visy
,
Géza Hitka
, and
Tamás Zsom

Abstract

Ethylene has key roles in triggering and speeding up ripening processes, which in tomatoes take the form of various qualitative changes. Tomatoes, just like all climacteric fruits, need a continuous ethylene exposure to accelerate ripening. Therefore, it is possible to use ripening regulators preventing ethylene binding. According to some studies, chlorophyll fluorescence measurements can be used at least as efficiently as tristimulus colorimetry classifying tomatoes based on maturity. Measurements were carried out by treating fresh tomatoes with 1-MCP (1-methylcyclopropene) at six different stages of ripening and studying the changes in chlorophyll content related quality characteristics (e.g. surface colour, chlorophyll fluorescence) during postharvest storage (two-week refrigerated storage at 15 °C followed by a two-week shelf life). According to our results, chlorophyll content and photosynthetic activity of the treated samples decreased much less than those of untreated ones. Additionally, anti-ripening treatment proved to be more effective on tomatoes at an earlier stage of ripening.

Open access

Abstract

In this work, the simulated adulteration of coconut drink by dilution with water was investigated using laser-light backscattering (LLB) imaging. The laser vision system consisted of six low power laser modules, emitting 1 mm diameter beams at wavelengths of 532, 635, 780, 808, 850 and 1,064 nm. The backscattering images were acquired by a grey scale camera with 12 bit resolution. Eight parameters were extracted to describe the backscattering profile. The methods of linear discriminant analysis (LDA) and partial least squares (PLS) regression were performed on LLB parameters for classifying and predicting dilution level of adulterated coconut drink samples. Based on the results, LLB signals responded sensitively to adulteration. LDA results showed that adulterated samples were correctly recognized with accuracies between 60 and 100%. PLS models were able to estimate the adulteration level of samples with coefficients of determination of 0.57–0.97 in validation. This result demonstrated the potential of laser-light backscattering imaging as a rapid and non-destructive optical technique for evaluation of coconut drink adulteration.

Open access

Talajnedvesség-tartalom mérése földradarral (GPR) és mezőgazdasági alkalmazhatóságának lehetőségei

Soil water content measurements with ground penetrating radar (GPR) and its application possibilities in the agriculture

Agrokémia és Talajtan
Authors:
András Herceg
and
Csaba Tóth

A talajnedvesség-tartalom variabilitásának mérését jelentősen megnehezíti a talaj heterogenitása és a környezeti változatosság. Jelenleg még nem fejlesztettek ki olyan univerzális módszert, amely a magas vagy alacsony talajnedvesség-zónák szántóföldi léptékű feltérképezésére alkalmas úgy, hogy a talajnak és a talajnedvesség áramlásának teljes zavarásmentességét nagy mélységben is biztosítja.

A talajnedvesség-mérés részben (talajkapcsolt), vagy teljesen roncsolásmentes (levegőkapcsolt) lehetőségét biztosítja a földradar (GPR), amely nagy felbontást és jelentős behatolási mélységet biztosít a közepes léptékű talajnedvesség meghatározáshoz, így hiánypótló technikát jelent a kisléptékű pontszerű és a nagyléptékű távérzékelt mérési technikák közötti metodikai hiány kitöltésére. Emellett jobb időhatékonyággal alkalmazható más roncsolásos és roncsolásmentes eljárásokkal összevetve.

A talajradart sikeresen alkalmazták a talajnedvesség-meghatározásra, de hidrológiai vizsgálatokban történő alkalmazásának nagy potenciálja ellenére nem minden körülmény között működik optimálisan. Felhasználhatósága többnyire olyan területekre korlátozódik, ahol viszonylag alacsony az elektromos vezetőképesség (az elektromágneses hullám gyenge csillapodására való tekintettel). Ezen túlmenően egyes talajradar módszerek működésének alapfeltétele a jól azonosítható és folyamatos jelvisszaverődés, továbbá a dielektromos állandó tekintetében a földradar-rendszerek térben folyamatos felszín alatti kontrasztot igényelnek.

A talajnedvesség és annak áramlása kulcsparaméter a mezőgazdaság különböző területein. A talajnedvesség (és a talajvíz) látja el a növényeket, ami elengedhetetlen feltétele a növények fejlődésének. Ennélfogva a talaj nedvességtartalmának, eloszlásának, áramlásának, valamint a beszivárgás sajátosságainak alapos és lokális ismerete az öntözés hatékony megvalósításának alapköve, különösen a félszáraz és száraz éghajlatú területeken.

A talajradar mérési alapjaival, valamint hasznosítási lehetőségeivel összefüggésben az elsősorban nemzetközi szakirodalmat összegezve megállapítható, hogy a GPR előnyös mérőeszköz lehet, amely segíthet a talaj nedvességeloszlásának feltérképezésében, tekintettel a beszivárgásra, a párolgás és a növényi vízfelvétel okozta vízveszteségre is. Következésképpen mezőgazdasági felhasználhatósága lehetséges.

A talajradar hasznos része lehet a „Smart farming”-nak (intelligens gazdálkodás), segítséget nyújthat a talajban elhelyezett talajnedvesség-mérő szenzorok kijelölésében. Különösen, ha a közelmúltban megjelent új, szimultán többeltolásos és többcsatornás (SiMoc) GPR rendszerre asszociálunk, amely gyors talajprofil-feltérképezést tesz lehetővé a hét vevőegységével, de a hagyományos egycsatornás GPR sebességével.

Ha a teljes roncsolásmentesség a cél, úgy a drónra szerelt levegőkapcsolt GPR-ek nyújthatnak lehetőséget. Megjegyzendő azonban, hogy a talaj-levegő határfelületen jelentkező szignifikáns jelcsillapodás (hullámszóródás) következtében a feltárási mélység jelentősen csökken.

A földradar végső soron mérési alapul szolgálhat a hatékony (precíziós) öntözési gazdálkodás kialakításához, és a megfelelő vízfelhasználási hatékonyságot biztosítva járulhat hozzá a precíziós mezőgazdasági programok megvalósításához.

Open access

Abstract

In order to improve the thermal performance of heat exchangers and air collectors, we insert various forms of artificial roughness, known as ribs, into the useful duct. These ribs promote the creation of turbulent flows and enhance heat transfer by conduction, convection and radiation.

However, the introduction of these ribs leads to an increase in pressure drop, requiring higher mechanical power to pump the heat transfer fluid. This experimental study focuses on estimating, using empirical approaches, the pressure losses induced by rectangular ribs with an inclined top. The ribs are made from 0.4 mm galvanized sheet steel.

An experimental set-up was designed to measure the head losses generated by the ribs, from the point of entry to the point of exit from the useful duct. Using the dimensional analysis method, correlations were established to evaluate head losses as a function of flow regime and rib geometry and configuration (including different geometries for rib arrangement over the configuration area).

Open access

Abstract

In this study, we compile the findings to date on using several cellulose-based materials as adsorbents of potentially toxic elements (PTEs) from wastewater. Furthermore, this review discussed the destiny of PTEs-loaded cellulose-based adsorbents and some sustainable methods for their management, hoping to close the pollution loop.

Open access

Abstract

In our study, using a combination of eye-tracking parameter analysis and the van Westendorp method, we investigate whether participants pay more attention to products that they perceive as more expensive or to those that they prefer in the ranking process. The experiment involved 50 participants, a questionnaire with ranking and pricing tasks, and an eye-tracking measurement. Three wine varieties (Irsai Olivér, Rosé and Merlot-Shiraz) and three different label alternatives were tested. When comparing the results of the ranking and the pricing tasks, the product that is considered more expensive is not always the one that is most appealing to the participants. If we compare the results from the analysis of the eye-tracking parameters and the pricing, we can say that in all cases the labels that received the most visual attention were those that were priced more expensively by the participants.

Open access