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Abstract

One of the most important components in spreads is the fat phase. The characteristics of the used fat determine most of the quality factors of the products such as viscosity, texture, colour, shelf life, etc. In these kinds of products, the commonly used fat is palm fat, however, in recent years it has had a bad press due to its negative environmental impact and health concerns. Therefore, the aim of our research was to develop a palm oil free hazelnut spread. We investigated the effect of replacing the fat in the fat phase with milk fat or coconut fat to the apparent viscosity, colour and texture properties of the product. According to our results the palm fat had the highest and coconut fat had the lowest viscosity. In texture analyses palm fat and milk fat showed no significant difference in hardness and in work of penetration. Coconut fat was significantly different in every texture attributes from the other samples. In the case of colour measurement all samples were significantly different. Despite the observed differences in some parameters the suitability of milk fat for hazelnut spread production should be further investigated (sensory analyses, shelf-life).

Open access

Abstract

The aim of this study was to investigate microencapsulation of palm oil fractions (palm olein (POL) and 90% palm olein+10% palm stearin (POS)) using skim milk powder (SMP) and maltodextrin (MD) by spray drying. Twenty-seven emulsions with POL were prepared to determine appropriate solid content (SC) and oil/coating material ratio (O/CM) of the emulsions to be fed into the spray dryer. Emulsion properties, such as viscosity and stability, were affected by SC and coating materials. The effects of coating materials used in microencapsulation of POL and POS were also tested by using different ratios of SMP and MD. The microencapsulation efficiency (69.28–84.97%), the microencapsulation yield (14.50–31.79%), and the peroxide value (4.12–7.07 meq O2/kg oil) of the powders were affected by the coating materials (P < 0.05).

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Abstract

In the current study, cakes were prepared with the addition of different levels of chia gel obtained by soaking 1 part of chia seeds in 9 parts of water by weight. Mix was allowed to stand for 30 min for gel formation and seeds were left in the gel and later incorporated into the batter. The addition of chia gel to cake batter to partially substitute the fat from the basic recipe (control) resulted both in improved quality characteristics at all levels of substitution and reduction of caloric value, at the expense of energy from fat, especially at higher reduction levels (40 and 60%). The fat replacement at 40 and 60% had a caloric value decrease by 48 kcal per 100 g compared to the control and respectively the energy at the expense of the fat was 37.9 and 25.7% (reduction by 71.3 and 48.3%). Sensory evaluation demonstrated good acceptability for all the products with slight prevail for the samples with 40% followed closer by those with 20% fat replacement. Hence, chia gel proved to be a good alternative for fat substitution in baking goods recipes while preserving the quality and sensory parameters aiming to produce healthier foods.

Open access

Abstract

Animal blood is a by-product, which can be utilized in a value-adding way instead of being wasted. Allergen substitution is an obvious possibility because many properties of blood plasma are similar to egg white. Techno-functional and sensory attributes (water activity, moisture content, colour and texture related properties) were measured by instrumental methods. The allergenic egg powder can be substituted by non-allergenic blood plasma powder in sponge cakes, but the change in the ingredient has an effect on hardness and tolerating compressive stress until the breaking. In the case of water activity and moisture content, sponge cakes with blood plasma were as desirable as sponge cakes with egg.

Open access

Abstract

Presented work evaluated how quality of catfish fillets is affected by treatments using lactic acid or lysozyme in combination with chlorine. Fish fillets without skin were consecutively immersed and washed in 100 ppm chlorine solution and sprayed with 2.5% lactic acid or 0.5% lysozyme solution. Control samples were only washed with water at the same time. Samples were stored at 2 °C for 10 days in vacuum packaging. Parameters of pH, firmness, surface color and microbial cell counts (cfu/g) were measured on the 1st, 4th, 7th and 10th days. Especially the latter had high importance from the point of view of food safety. Catfish fillets shown decreased survival of microorganisms as a result of treatment. Lysozyme and lactic acid achieved 1.8 and 2.4 log cfu/g reduction, respectively. Lower cell counts were observed for all treated samples compared to control during 10 days. Chlorine in combination with lactic acid achieved the best efficiency. The results are promising and suggest that combined treatment is able to improve safety by controlling microorganisms on fish fillets during cold storage.

Open access
Progress in Agricultural Engineering Sciences
Authors: Viktória Zsom-Muha, Lien Le Phuong Nguyen, László Baranyai, Géza Hitka, Zsuzsanna Horváth-Mezőfi, Gergő Szabó, and Tamás Zsom

Abstract

Among improper harvest and/or postharvest storage conditions, the effect of direct sunlight plays an important role in quality degradation of potato resulting in the development of green surface color based on chlorophyll formation associated with the formation of poisonous chemicals – glycoalcaloids – known as α-chaconine and α-solanine. Yellow skinned and fleshed potatoes with or without visible initial marks of green surface color were stored at normal room temperature under direct natural (sun)light conditions for almost two months. The aim of this study was the preliminary investigation of the sunlight induced formation of chlorophyll related compounds in potato indirectly by the detection of chlorophyll development. This attempt was based on nondestructive determination of chlorophyll related spectral and fluorescence indices for both sunlight exposed and unexposed potato sides. For both potato groups the chlorophyll content related DA-index® and chlorophyll fluorescence characteristics (F0, Fm, Fv and Fv/Fm) increased during the storage period representing chlorophyll formation. In the case of Fm, Fv and Fv/Fm values, the yellow samples reached the values of the initial spotted green samples by the 7th–9th days. From this time, the chlorophyll fluorescence values changed only minimally. After storage day 34, in the case of both at day 0 yellow and green spotted potatoes, the sunny side's F0 value was lower than that of shaded side. Close relationship was found between the results of Walz monitoring-PAM (Pulse Amplitude-Modulated) chlorophyll fluorometer and the PSI (Photon Systems Instruments) chlorophyll fluorescence imaging device (e.g. Fv R2 = 0.7226). According to our preliminary results, the Vis/NIR DA-meter®, the monitoring-PAM and the chlorophyll fluorescence imaging fluorometers were found to be suitable nondestructive devices for further investigations concerning the postharvest chlorophyll formation based greening phenomena, which is associated with solanine development in potato.

Open access

Abstract

Sensory properties of foods mainly affect purchasing decisions. In case of sausages, deterioration of pigments of meat and spices cause discolouration, while lipid oxidation leads to the formation of off-odours, and these two processes are connected. Lipid oxidation promotes the conversion of pigments, while the formation of metmyoglobin accelerates lipid oxidation. The scope of the study was to investigate the relationship between the amount of malondialdehyde equivalents (MDA) and CIELAB colour coordinates in a Hungarian sausage with paprika, sliced and stored under refrigerated conditions for 10 weeks. We detected negative correlation (P < 0.001) between the MDA-level and a* and b*; and positive correlation (P < 0.001) between the MDA-level and L*. The observed correlation between MDA level and colour coordinates supports the assumption that the oxidation of lipids and pigments are interrelated in the case of sausage with paprika.

Open access

Abstract

Soybean is one of the most important leguminous crops that contributes to human alimentation and animal feed. Soybean grain with its high protein and valuable lipid content is an essential component for the food and feed industries worldwide. Apart from the genetically determined quality characteristics of a certain variety, management practices may have an influence on the manifestation of quality parameters. At the Department of Agronomy, Hungarian University of Agriculture and Life Sciences, agronomic impacts on grain yield, protein and lipid content of soybean crop has been studied in a replicated field trial. Nitrogen (N) application and various means of weed control were studied, and grain yields were evaluated in accordance with the treatments. The results obtained suggest, that N topdressing has positive but no significant effect on grain yield, however, the means of weed control resulted in an almost twofold yield improvement compared to the control. The treatments had diverse effects regarding both protein and lipid contents of the crop yield, however, significant protein and lipid yield improvement of the crop could be observed.

Open access

Abstract

The availability of thermophysical properties of both foods and their constituents is of considerable importance to the industry. The thermal effusivity is one of the less explored thermophysical parameters. It governs the penetration of heat into materials and is defined as the square root of the product of thermal conductivity of the material, volume-specific heat capacity, and density. This paper describes the application of a relatively new inverse photopyroelectric method (IPPE) to determine thermal effusivity of dehydrated whey protein isolate and egg white powder versus protein content. In both cases the effusivity values decreased linearly with increasing protein content. One percent increase in protein content of whey protein isolate and egg white lead to 6.5 and 7.2 Ws1/2 m−2 K−1 decrease in effusivity values, respectively.

Restricted access
Progress in Agricultural Engineering Sciences
Authors: Mai Sao Dam, Vuong Duc Nguyen, Tamás Zsom, Lien Le Phuong Nguyen, and Géza Hitka

Abstract

The effect of storage temperature and ozone treatment on the post-harvest quality of cucumber and tomato was investigated. Cucumber and tomato were stored together with or without gaseous ozone treatment at 20 °C and 14 °C for 16 days. Firmness, color, weight loss, DA index and decay percentage of samples were evaluated during storage period. The results showed that the combination of ozone treatment and cold storage could maintain the quality of these horticultural products and decreased the decay incidence. Additionally, this combination also reduced the weight loss of samples during storage. Furthermore, ozone treatment maintained the green skin color of cucumber. No sign of chilling injury occurred during storage at 14 °C. Commodities stored with approximately 0.1 ppm gaseous ozone at 14 °C retained the firmness compared to other treatments until the end of the experiment. This study suggests a promising use of gaseous ozone treatment in storage chamber where ethylene-producing and ethylene-sensitive vegetables are stored together.

Open access