Whey and buttermilk are the main by-products of the dairy industry, both having excellent nutritional properties. Buttermilk contains a unique component, the milk fat globule membrane (MFGM). MFGM ...contains bioactive compounds with positive health effects like antitumour or cholesterol-lowering impact. Whey proteins are found in whey and are a source of bioactive peptides acting positively on coronary, gastrointestinal, immune and nervous systems. Yet, buttermilk and whey are insufficiently utilized in functional food production. Various technological solutions have been studied in order to increase the production of foods based on whey and/or buttermilk whereby the production of beverages appear to be most acceptable from the economic and technological point +of view. Thus, the aim of this paper is to give an overview of current knowledge about the possibilities of creating whey and/or buttermilk beverages.
The main objective of this study was to compare chemical, rheological and sensory characteristics of kefir produced by using kefir grains and kefir starter. The intent was also to investigate whether ...it is plausible to use a combined inoculum (kefir grains and starter) in order to obtain a kefir with improved characteristics in terms of sensory and rheological characteristics. Kefir samples were produced at 25 °C and 35 °C by using starter culture XPL-1, kefir grains and their combinations. All of the produced kefir samples were analysed for acidity, total dry matter, ethanol content, syneresis, viscosity and were sensory evaluated by a specially trained panel. There were no significant differences considering the total dry matter, syneresis, ethanol content and acidity. Excess viscosity was observed in samples produced by starter culture at 35 °C, which was described as untypical, yoghurt like and unsatisfactory by a sensory panel. The sample produced at 25 °C by equal amounts of kefir grains and starter culture received the highest scores at sensory evaluation and showed the best potential for optimizing the further use. Further investigations need to focus on examining kefir properties during the storage period, especially regarding microbiological and sensory properties, ethanol content and texture profile.
In recent years, functional foods and bioactive components in foods have
drawn a lot of attention as well as interest of food scientists, nutritionists, health professionals, and consumers. The ...advent of this new food category has been facilitated by increasing scientific knowledge about the metabolic and genomic effects of diet and specific dietary components on human health. The relationship between health and diet is well known and it is a main key for prevention of variety of diseases. Milk is considered as a very good source of bioactive components and it has been known to contain macro- as well as micronutrients of high nutritional and therapeutic value. Also, bioactive components have been exploited from milk and dairy products for application in functional foods and for potential pharmaceutical use. Biologically active compounds guard neonates and adults against pathogens and illnesses. Some major bioactive components of milk are derived from caseins, whey proteins, lipids, lactoferrine, vitamins, immunoglobulins and growth factors. The aim of this paper was to provide
an overview and explain the health effects of already known and recently detected bioactive components derived from bovine milk on humans.
Funkcionalna hrana i bioaktivni sastojci hrane posljednjih su godina privukli veliku pažnju i zanimanje znanstvenika, nutricionista, zdravstvenih djelatnika te samih potrošača. Samo saznanje o funkcionalnoj hrani uvelike je olakšano napretkom znanosti te spoznajama o metaboličkim i genomskim utjecajem na prehranu te utjecajem određenih sastojaka hrane na ljudsko zdravlje. Poveznica zdravlja i prehrane je dobro poznata i glavni je ključ za prevenciju mnogih bolesti. Mlijeko se smatra izuzetno dobrim izvorom bioaktivnih sastojaka, a odavno je poznato da je namirnica s dobrim sastavom makro- i mikronutrijenata. Osim što se bioaktivni sastojci mlijeka prirodno nalaze u mlijeku i mliječnim proizvodima, oni se iz istih izoliraju te se koriste kao bioaktivni sastojci za proizvodnju funkcionalne hrane ili pak u farmaceutskoj industriji. Bioaktivni sastojci mlijeka imaju zaštitnu ulogu, kod novorođenčadi i odraslih, protiv patogena i bolesti. Glavni bioaktivni funkcionalni sastojci mlijeka nastaju iz kazeina, proteina sirutke, mliječne masti, laktoferina, vitamina, imunoglobulina i faktora rasta. Stoga je cilj rada bio dati pregled poznatih i onih tek nedavno detektiranih bioaktivnih sastojaka mlijeka te njihov utjecaj na zdravlje čovjeka.
Along with the constant increase in the cheese milk production, the world whey production is increasing constantly too (>2 % per year). The excellent nutritional properties attributed to whey are ...mainly conditioned by the presence of highly valuable proteins with wide range of biological and functional properties. The main whey proteins are β-lactoglobulin (β-Lg) and α-lactalbumin (α-La) which are extensively used in functional foods and beverages, infant formulas, sport diets, but are a very good source of bioactive peptides too. Along with casein, β-Lg is most commonly made responsible for causing food allergies, especially in infants whose digestion system isn’t completely developed. Hence, there is a great interest for removing β-Lg prior to whey utilization in certain products. At the same time α-La was recognized as the nutritionally most valuable protein and might be regarded as an ideal ingredient for infant formulas. Thus, the aim of the present paper was to give an overview of the currently available methods for α-La isolation, and to highlight their advantages and disadvantages as well. Also, this paper reviews the most recent insights related to the structure and physiological significance of α-La.
The use of ultrafiltration in whey processing is limited by reduced flux and separation originating from fouling. Since the processing conditions applied determine ultrafiltration performance, this ...study focused on investigating the influence of temperature (20 or 50 °C) and the pre-treatment applied (pasteurisation, cross-flow microfiltration) on the ultrafiltration of sweet whey using a 20 kDa ceramic membrane. The highest flux and the lowest total filtration resistance were recorded at 20 °C, with predominantly reversible fouling, most probably arising from protein deposition, while at 50 °C, calcium could have played an important role. Whey microfiltration using a 0.5 μm ceramic membrane enhanced ultrafiltration, giving significant flux increase and fouling reduction, while the obtained microbial reduction was almost equal to pasteurisation. Ultrafiltration of pasteurised whey at 50 °C proved to be least suitable, while ultrafiltration of fresh or microfiltered whey at 20 °C provided the most desirable conditions.
Ultrasonication and thermo-sonication belong to alternative, non-thermal food processing methods. The aim of this study was to investigate the influence of different ultrasound power inputs (240 W, ...320 W, 400 W) without and in combination with heat pre-treatment on microbial inactivation and sensory properties of rennet cheese whey in comparison with conventional pasteurization batch processes. Ultrasonication treatments had no impact on reduction of any group of studied microorganisms. Microbial inactivation caused by thermo-sonication treatments with pre-heating to 35 °C or 45 °C increased with nominal power input and/or exposure times and was probably due to the heat improved ultrasonic cavitation. Thermo-sonication treatments at nominal power input (400 W) and preheating to 55 °C were the most effective resulting in greater microbial reduction compared to that observed by simulating pasteurization processes, but occurred probably due to developed heat solely. Sensory properties after ultrasonication and thermo-sonication were considerably improved in comparison with that after simulated pasteurization processes. Mouth feel of whey samples was considerably better, there was no occurrence of sediment and colour remained unchanged in almost all samples.
Goat's or cow's milk was fortified with 2 g/100 g skimmed milk powder (SMP), whey protein concentrate (WPC) or inulin. All the milks were fermented with kefir grains at 25°C for 19 h and stored for ...10 days at 5°C. All the kefir samples were analysed on the 1st, 5th and 10th day of storage. The acidity level remained very stable in all the samples during the storage period. Goat's samples have significantly lower viscosity and slightly lower sensory profiles, mostly due to softer consistency. Concentration of ethanol was low, regardless of milk type used, especially for control samples.
The aim of this paper is to determine nutritive, functional, microbiological and sensory properties of probiotic beverages produced from different volume ratios of cow's milk and soy beverage (25:75, ...50:50 and 75:25). Pure cow's milk and soy beverage served as control samples. Fermentation was performed at 43 °C by a combined culture consisting of the probiotic strain
La5 and yoghurt culture. Viable counts of La5 strain in the produced beverages ranged from 7.52 to 8.20 log CFU/mL, which is above the probiotic minimum (10
CFU/mL). Lactic acid was the most prevalent organic acid in all samples (660.1 to 1003.0 mg/100 mL). The fatty acid profiles of fermented beverages were as follows: the mass fraction of saturated fatty acids was 22.2-82.7%, of unsaturated fatty acids 22.3-77.8% and of polyunsaturated fatty acids 15.5-65.9%. The main soy sugars were transformed well (80% stachyose and 50% raffinose conversion) into lactic acid during fermentation. Functional probiotic beverages were successfully produced from different volume ratios of cow's milk and soy beverage by
La5 and yoghurt culture. Mixing cow's milk with soy beverage significantly improved the sensory properties of the product, especially its smell, taste and colour. The acceptability test showed good acceptance by potential consumers of all fermented beverage samples except for the sample made from 100% soy beverage. In the end, the obtained results represent a good basis for further optimisation of the ideal volume ratios of cow's milk and soy beverage for production of fermented beverages characterised by good viability of probiotic bacteria as well as by good functional, nutritive and sensory characteristics.
In this study, operating conditions for the cross flow microfiltration (CFMF) of sweet whey were optimised. Filtrations were performed for 65 min at 20, 40 and 50 °C using ceramic membranes with ...different nominal pore sizes (0.1, 0.5 and 0.8 μm). Periodically, samples of whey retentate and permeate were taken and analysed for microbiological quality and physical and chemical properties. The best microbial reduction rates were achieved during filtration using a 0.1 μm membrane at 50 °C. The highest flux rates were achieved during filtration at 50 °C with all tested membranes. Fouling intensity was the lowest after filtration using a 0.5 μm membrane at 20 °C. According to all results obtained, the membrane with the nominal pore size of 0.5 μm appeared to be optimal for purposes of preserving the nutritional value, minimising membrane fouling and achieving appropriate microbiological quality of sweet whey.
Fresh (acid coagulated) cheeses belong to a group of soft unripen cheeses which are very popular among consumers. However, owing to the specific composition and properties, these cheeses have a ...limited shelf life. The aim of this study was to investigate the effect of modified atmosphere packaging (MAP) onto fresh cheese and to compare it with the commonly used packaging under atmospheric air and vacuum. The produced fresh cheese was packed under normal atmosphere (air), vacuum and modified atmosphere of following composition: (1) 60%N
2
:40%CO
2
; (2) 70%N
2
:30%CO
2
. All cheese samples were cool stored for 18 days, whereby the sampling and analyses were conducted every 3 days. During the storage period, there was a continuous decrease in acidity (from 4.66 to 4.47), while the viable counts of the monitored microorganisms increased in the control sample. However, in samples packaged under vacuum and modified atmosphere a slighter decrease in acidity (no result under 4.50) and inhibited microbiological growth were detected. Scores of sensory evaluations were high for all samples (17.63–19.73), whereby the sample packed under MAP with ratio 70%CO
2
:30%N
2
obtained the best average score of 17.72 at the end of the 18-day storage period. Other analyses confirmed that vacuum and MAP prolong the shelf life of fresh cheese while preserving its physico-chemical and sensory characteristics.
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