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Abstract
This study investigates the effect of 2% lactic acid and 2% ascorbic acid mixture on the quality parameters of red deer meat and beef. After treatment samples were stored at 4 ± 1 °C. The following meat quality parameters were evaluated: pH, color, and microbiological count on days 1, 7, 14, and 21. The results showed that at the end of the experiment, the pH of the treated samples was slightly higher than the non-treated samples, indicating that the lactic acid and ascorbic acid mixture had a mild acidifying effect on the meat. The color of the treated and non-treated samples did not show any significant difference. However, the microbiological count in the treated samples was lower than the non-treated samples. These findings suggest that an acid mixture could be used as a natural preservative to enhance the microbial safety of red deer meat and beef.
Abstract
This study focuses on the contribution of maturity stages and 1-methylcyclopropene (1-MCP) treatment to the quality of ‘Zebra’ apricot. Samples were harvested at mature-green, yellow and orange maturity stages. Fruit were treated with gaseous 1-MCP (24 h at 1 °C), followed by cold storage at 1 °C for 6 weeks. Non-destructive measurements were used to evaluate the quality changes of apricot during storage. The results showed that the maturity stages significantly affected the weight loss. The loss of weight increased rapidly for orange ripeness stage fruit, more than others during storage. Both maturity and 1-MCP affected the stiffness of apricot. The 1-MCP could delay the softening of fruit. The green and yellow maturity stages retained higher values in stiffness compared to orange. No significant difference in hue angle values was observed between 1-MCP treated and control fruit, however hue angle value decreased strongly in mature-green harvested fruit. The maturity stages and 1-MCP treatment had the effect on quality changes of apricot over storage. The maturity stage was an important factor contributing to the effectiveness of 1-MCP application as it was observed in slower softening after harvest.
Abstract
Besides their unique taste and texture, mushrooms are a promising source of important nutrients, including dietary fiber, amino acids, minerals, and vitamins. Fresh mushrooms, however, can only endure for a brief time, typically up to three days at ambient conditions. Different methods have been used to preserve mushrooms for a prolonged period, such as drying, cooking, frying, irradiation and fermentation. The objective of the current study is to investigate the effect of different pre-treatments and fermentation on physicochemical, textural, and microbial properties of oyster mushrooms. The fresh oyster mushroom was considered as control and 6 alternative pre-treatment methods were used as; blanching in water, steaming, oven cooking, microwave, High Hydrostatic Pressure and UV Light treatment. Moisture, pH, yield, color, texture, and microbiological analyses were performed on each pre-treatment group before and after fermentation. Our results showed that the quality attributes of oyster mushrooms were significantly affected by the usage of different pre-treatments.
Abstract
The presented study investigated the effects of edible coatings with concentration of 2%, 3% and 4% of starch (w/v) on the weight loss and firmness loss of green asparagus during 4 days of storage at room temperature (26 ± 2 °C, 65–70% RH). According to the results, the coated asparagus exhibited significantly slower deterioration rate than the uncoated control samples. This was indicated by the decrease in weight loss and increase in firmness (P < 0.05). After the storage period, the samples treated with 4% starch formula retained the highest quality. Furthermore, the assessment of asparagus quality throughout the storage period involved the use of the line laser scattering technique. Extracted parameters of laser scattering signal discriminated samples with linear discriminant analysis (LDA), in which the correct recognition rate of the treated groups was 75.26% and the storage time was 70.54%. This study showed the potential of laser scattering as a rapid, non-invasive, and practical optical method for assessing the quality of asparagus during storage.
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.
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.
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.
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.
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.
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
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.
