Potravinarstvo Slovak Journal of Food Sciences
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Technical efficiency and factors affecting rice production in tidal lowlands of South Sumatra province Indonesia
Get PDFRice has been the staple food for most Indonesians, so the rice consumption in Indonesia is considerably high. Rice is cultivated in many agroecosystems, including tidal lowlands. Some tidal lowlands are considered suitable for rice cultivation. Therefore, tidal lowlands may support food security in Indonesia. However, productivity remains a problem in which inputs are not used efficiently. This study aims to determine the technical efficiency and identify factors affecting rice production in tidal lowlands of South Sumatra, one of main rice barns in Indonesia. A survey was conducted by interviewing 93 farmers in Telang Rejo Village. A data envelopment analysis (DEA) with output-oriented and variable returns to scale (VRS) approach was applied to measure technical efficiency score from each farm observed. An ordinary least square (OLS) regression with a Cobb-Douglass production function approach was employed to analyse the factors affecting rice production in tidal lowlands of South Sumatra, Indonesia. The results showed that majority of rice farms in the tidal lowlands of South Sumatra Indonesia were inefficient. There were 44 rice farms (47.31%) that were efficient, 5 rice farms (5.38%) that were inefficient under increasing returns to scale and 44 rice farms (47.31%) that were inefficient under decreasing returns to scale. The inputs, such as nitrogen, phosphorus, and potassium fertilisers, herbicides, insecticides and fungicides had positive significant influences on rice production in the tidal lowlands of South Sumatra, Indonesia
Thermal stability of prepared chicken feet gelatine gel in comparison with commercial gelatines
Get PDFGelatine is, due to its functional properties, currently widely used not only in the food industry (in the production of confectionery, dairy products, canned food) but also in pharmacy (soft and hard capsules) and cosmetics (creams, lotions) where it applies its ability to form thermoreversible gel stronger than most other gelling agents. What is more, it provides further excellent properties including emulsifying, foaming, stabilizing, film-forming, water and fat binding, texturizing, thickening, and adhesive attributes which makes it a very important hydrocolloid. Gelatine is obtained from the raw material of animal tissues containing collagen, usually mammalian skin or bones. For religious reasons in some countries, pork or bovine gelatine must be replaced by an alternative form, such as poultry or fish gelatine. The quality of gelatine is assessed mostly by the strength of gelatine gel which strongly depends on ambient temperature or humidity. Extraction conditions may also significantly affect the quality of gelatine. This study examined possible changes in the strength of gelatine gels prepared from laboratory-produced chicken feet gelatine and compared them with commercially available pork and beef gelatines at temperatures of 23, 29, and 35 °C at 60 and 80% humidity. While at 23 °C thermal stability of prepared chicken gelatine was monitored higher than in commercial gelatines, experiments at 29 and 35 °C provided equivalent results for chicken and commercial gelatines. Therefore, prepared chicken gelatine offers a significant potential to become an alternative to traditional gelatines. The information about gelatine gels thermal stability is of great importance for applications not only in the food; but also in the pharmaceutical industry
Meat performance of Japanese quails after the application of bee bread powder
Get PDFThe aim of the study was the evaluation of meat performance of Japanese quails after the addition of bee bread powder into their diet. A total of 80 one day-old Japanese quails were randomly divided into 4 groups (n = 20): the control group (C) without additional supplementation, the experimental group E1 supplemented with 2 mg bee bread powder per 1 kg of feed mixture; the experimental group E2 supplemented with 4 mg bee bread powder per 1 kg of feed mixture and the experimental group E3 supplemented with 6 mg bee bread powder per 1 kg of feed mixture. The groups were kept under the same conditions and the quails were slaughtered at 56 days of age. Based on the results, we can conclude that the application of bee bread powder generally has not confirmed a positive effect on the meat performance of Japanese quails, regarding to the quantities of bee bread powder in the experimental groups
Relationship between the activity of guaiacol peroxidase and the content of photosynthetic pigments in tea leaves
Get PDFThe dynamics of guaiacol peroxidase and photosynthetic pigments in 3-leaf sprouts (flushes) of tea plants were studied. The presence of declines and peaks in the activity of the enzyme associated with the meteorological conditions of each month was noted. It is shown that there is a direct relationship between the increase in enzyme activity and hydrothermal factors. The most significant correlation was found between the activity of GPO in a 3-leaf tea flush and the amount of precipitation (r = 0.86). The highest activity of guaiacol peroxidase during the entire vegetation period is distinguished by the Sochi variety and form 582. The lowest activity was observed in forms 3823 and 2264, which indicates a low intensity of redox reactions in these plants in stressful situations. Determining the dynamics of the pigment complex revealed its dependence on hydrothermal factors. Studies have shown that precipitation is a significant factor affecting the pigment complex of tea plants. It was found that the largest amount of green pigments is synthesized by leaves at the beginning of active vegetation (May). The participation of the pigment apparatus in the adaptation of the tea plant is directly related to carotenoids, the increase in the number of carotenoids coincides with the period of drought. In the content of photosynthetic pigments and the activity of guaiacol peroxidase manifest genotypic features. The revealed patterns are common to all tea plants
Research of milk fat oxidation processes during storage of butter pastes
Get PDFBasic quality indicators studied: acidity, peroxide, anisidine value and integrated value of complete fat oxidation. Butter paste was selected as a reference, consisting of butter, skim milk powder and fat-soluble emulsifiers. Peroxide value during storage at the temperature of (4 ±2 °С) for the first 4 days did not exceed 5.0 1/2 О mmol.kg-1, on the 15th day fat peroxide value of butter paste with milk-vegetable protein exceeded permissible limits that is indicative of milk fat contamination. At the temperature of (-3 ±1 °С) butter paste fat couldn't be qualified as fresh when storing during 15 days, peroxide value exceeds permissible limits on the 25th day of storage. Rising of the peroxide value above 5 1/2 О mmol.kg-1 was detected on the 25th day of storage, exceeding of threshold value was on the 45th day. It was established that rate of oxidation processes in butter pastes with vegetable protein is the highest among all studied samples in each particular control and observation point. It was determined that the rate of secondary lipid oxidation depends on the storage temperature and is observed when storing butter paste samples at a temperature of (-3 ±1 °С) on the 10th day, (-24 ±2 °С) – on the 30th day of storage. Acid value did not exceed recommended limits (2.5 °K) and was on average – 2.3 °K when storing butter paste during 10 days at a temperature of (4 ±2 °С); 2.1 °K during 20 days at the temperature of (-3 ±1 °С), 2.4 °K during 40 days at the temperature of (-24 ±2 °С). In view of obtained results of fat phase stability evaluation of studied butter pastes, the following storage maximum time is recommended: at the temperature of (4 ±2 °С) ‒ 7 days, at the temperature of (-3 ±1 °С) – 15 days, at the temperature of (-26 ±2 °С) ‒ 30 days
Evaluation of the physiological state of feijoa (Feijoa sellowiana Berg) in subtropical Russia
Get PDFThe article presents the results of research examining varietal diversity with respect the activity of oxidative enzymes (EC 1.11.1.6) and the dry matter and Proline accumulation of leaves under optimal and stressful conditions. For feijoa, the most stressful period in the subtropics of Russia, with respect to hydrothermal conditions, occurs between July and September. Studies have shown that the highest degree of enzymatic activity is observed in August in the ‘Superba’ variety of feijoa, which was used as a control in this study, and the lowest level of activity was observed in the 'Sentjabrskaja' variety. The long-term water deficit experienced in September coincides with fruiting in feijoa. This causes a change in catalase activity in leaves, which is maintained until it is inhibited. Form ShV-1 of feijoa is characterised by its metabolic stability. In fact, the activity of oxidative enzymes in leaves of the variety is stable. Dry matter content per unit area increases as the leaf grows. During the drought period, which coincides with active fruiting, the leaves of the ‘Dachnaja' variety and the ShV-1 form accumulate significantly less dry matter than other varieties. In the ‘Dagomysskaja' variety, the intensity of organic matter consumption via respiration and outflow exceeds visible photosynthesis, which is expressed as a negative value (average = 1.96 g.dm-2 h). To fully characterise the physiological state of feijoa plants under the influence of abiotic factors and catalase activity in the humid subtropics of Russia, indicators of dry matter accumulation and true photosynthesis intensity can be used
Personalized nutrition and “digital twins” of food
Get PDFMathematization of research is one of the most effective methods of virtual substantiation of foodstuff recipe and technology. This approach allows creating a product that meets consumer's individual needs, i.e. personalized foodstuff (ethnicity, cultural preferences, regional and environmental characteristics, lifestyle), and at the same time reducing the time and cost of decision-making. The article discusses the hypothesis that the “digital twin” of a food product is a virtual model of the product, namely its mathematical model (simulation model). A simulation model is a logical and mathematical description of a food product that is used to conduct a computerized experiment in order to design desired characteristics and properties. The “digital twin” combines all variety of factors from chemical composition, functional and technological properties to organoleptic indicators. The application of the “digital twin” model of the foodstuff will allow: (1) reacting quickly to changes in the composition, properties and types of raw ingredients, (2) adjusting the product recipe in response to changes in consumer preferences, (3) designing products with a given chemical composition, nutritional value and functional orientation, (4) creating functional, specialized products taking into account the metabolism of nutrients (ethnicity, cultural preferences, health status and clinical factors). Products adapted to the needs of small categories of people will help reducing the risks for those who already have diseases, and will meet the needs of those who would like to make their diet more appropriate to individual needs. The proposed approach to creating a model of the “digital twin” of the foodstuff includes several stages. The first stage involves optimization of the nutritional and biological value of the designed product. The second stage is related to designing the food product’s structural forms. But even if the recipe of a food product is optimally selected in the first stage, it does not guarantee its transformation during processing into a stable system with the required structural, mechanical, functional and technological parameters. Evaluation of the developed food product’s efficiency is possible only by analysing numerous and various parameters and indicators. It is convenient to generalize (convolute) many parameters and indicators into a single quantitative dimensionless indicator. To assess the quality and adequacy of the food product, it is suggested to use an integral indicator in the form of additive convolution – the ‘functional’ of the food product quality
Assessment of possibilities of strawberry jam reformulation
Get PDFThe prevalence of excessive weight gain, obesity, and associated diseases are permanently increasing. Therefore, the interest in food products with a composition suitable for people with the aforementioned health problems is also on the rise. The changes in food composition, nowadays often called reformulation, are mainly focused on reducing the amount of salt, sugar, or fat. Strawberry spreads with different sugar (10 – 40%) and strawberry (20 – 50%) content were prepared and the influence of strawberry jam composition on gel stiffness, colour, and sensory parameters was studied. This study aimed to determine the sensorial and technological limits (sugar and strawberry content) of strawberry jam reformulation. Carrageenan was chosen as a suitable gelling agent for the preparation of these reformulated strawberry products. strawberry spreads. The applicable concentration of carrageenan for the ideal stiffness of strawberry spreads was 2%. The results of the maximum compression force show a statistically significant increase of gel stiffness with increasing addition of strawberry puree, the effect of sugar content was also statistically significant (p = 0.05). This study showed that strawberry spreads with low strawberry and/or sugar content are sensorially acceptable
Effect of supplementation with solid-state fermented feed in the diet of laying hens on egg qualitative variables
Get PDF The aim of this experiment was to evaluate the effect of the supplementation of laying hens diet with solid-state fermented feed on egg qualitative variables. The diet of laying hens was supplemented with 10% and 15% of solid-state feed fermented by the low filamentous fungal strain Mortierella alpina CCF 2861. For the trial, 30 Lohmann Brown classic layers, aged 17 weeks, were selected and individually weighed and divided into three groups (control and two experimental groups). The control group of laying hens was fed with basic feed mixture and the experimental groups received the same diet as a control group, but enriched with supplementation of solid-state fermented feed. The first experimental group was fed a diet supplemented with 10% of fermented feed and the second experimental group with 15% supplementation. The following egg qualitative variables were observed: the egg weight, Haugh units, quality grade, air cell depth, percentage of the shell, yolk and albumen, eggshell breaking force, pH of egg yolk and albumen, egg yolk colour, and antioxidant activity with the extent of lipid oxidation in egg yolk samples. The pH of yolk and albumen did not show differences between all examined eggs originating from the experimental groups of laying hens (p >0.05). The eggs from both experimental groups had a significantly higher eggshell hardness than eggs produced by the hens of the control group (p <0.05). Antioxidant activity of egg yolk of experimental samples increased with the supplementation of fermented feed in the diet of laying hens (p <0.05). The specific lightness of egg yolk colour increased significantly in the experimental group with 15% of supplementation (p <0.01). The obtained results showed that feeding laying hens with fermented feed positively affected the quality of produced eggs. This was the first study and further investigation before using the fermented feed in commercial laying hen farms is necessary
Analysis of the possibility of fish and meat raw materials combination in products
Get PDFAspects for the use of regional raw materials in ground food technology require further study of functional and technological properties to be able to predict them depending on the chemical composition of raw materials and processing methods. The aim of our research was to comparatively study the chemical composition, functional-technological, rheological properties of fish raw materials, and duck meat in terms of their possible compatibility in meat-containing products. The subject of our research was representatives of the regional aquaculture Carassius gibelio and Hypophthalmichthys molitrix, as well as the meat of Muscovy duck (Cairina moschata). It has been established that the nutritional value of freshwater aquaculture objects Carassius gibelio and Hypophthalmichthys molitrix is virtually identical in protein and fat content, making them interchangeable in terms of nutritional balance when developing the combined product. The ratio of protein and fat to water for duck meat is higher 3.54 – 4.88 times that of aquaculture, which can be used in the selection of components of the formulation of emulsified products, taking into account the nutrient balance. It has been confirmed that the addition of salt enhances water holding capacity, water binding capacity, and fat holding capacity. Water holding and water-binding capacities of minced fish are higher due to higher water levels, which, combined with the low-watering duck meat, can be predicted to create a forcemeat system with high functional-technological properties. The ability to emulsification and retain fat in the state of emulsion in minced duck meat has proved to be better, which when combined with fish minced meat can compensate for the ability to retain fat in the system of combined products. A combination of regional aquaculture with waterfowl meat will not only improve the functional and technological parameters of combined minced systems but also balance them by correcting the composition of proteins and fats