Partial replacement of saturated fats in liver pâté by an olive oil-in-water emulsion containing ß-glucan shows no compromise in sensory and storage oxidation of lipids and protein.

BACKGROUND: The consumption of olive oil has been shown to have a positive effect on preventing obesity and hypertension. At the same time, it is recommended to avoid processed meat products as they contain saturated fats. The inclusion of highly unsaturated lipids in food products can lead to rapid oxidation and deterioration of sensory characteristics. The objective of the current work was to encapsulate olive oil and incorporate it into traditional Polish liver pâté. The oil-in-water emulsions were formulated with varying levels of oat ß-glucan and were evaluated for droplet size, pH, encapsulation efficiency and rheology. The liver pâtés made using the emulsions with and without ß-glucan were then evaluated for pH, texture, colour, lipid and protein oxidation, thermal stability and sensory properties. RESULTS: The results showed that the oil-in-water emulsions had a 100% encapsulation rate of olive oil after 30 days of storage at 4 °C, regardless of the presence of ß-glucan. Although the texture of the emulsion-enriched liver pâté was different from that of the control, this difference was reduced when ß-glucan was added to the emulsion and then to the pâté matrix. CONCLUSION: Replacing 50% of animal fat with an olive oil emulsion enriched with ß-glucan did not result in any compromise of sensory properties, increase lipid or protein oxidation. These results suggest that it is possible to replace saturated lipids with omega-3-rich olive oil. © 2024 Society of Chemical Industry.

Replacement of milk fat by rapeseed oil stabilised emulsion in commercial yogurt.

The incorporation of lipid droplets and further characterization of matrices within dairy products may be possible using such adjacent particles as protein complexes/lipids. Among the range of varied emulsions and their functionalities, great attention has recently focused on the fabrication of high internal phase types. Feasibly, stable alternatives structured with health-beneficial lipids like those derived from plants could replace saturated fatty acids. As a fat replacement strategy, the fate of incorporated HIPE would require some adjustments either with storage stability and/or structural feat for the food matrix. Therefore, the replacement of milk fat by rapeseed oil stabilised emulsion in commercial yogurt was investigated. This involved 25%, 50% and 75% rapeseed oil respectively assigned as low (LIPE), medium (MIPE), and high internal phase emulsion (HIPE). Specifically, emulsions were examined by droplet size, encapsulation, pH, zeta potential, phase separation, and rheology. The fat free yogurt supplemented by HIPE were examined by droplet size, zeta potential, pH, color, sensory, texture and microbiological aspects against positive (regular milk fat) and negative (fat free) yogurt controls. Results showed increasing rapeseed oil contents would form smaller droplet-like emulsions. Within the yogurt matrix however, incorporating HIPE would seemingly reduce oil droplet size without much compromise to bacterial viability, sensory, or texture. Overall, this simple method of lipid alternation shows promise in dairy products.

Effects of Concentration and Type of Lipids on the Droplet Size, Encapsulation, Colour and Viscosity in the Oil-in-Water Emulsions Stabilised by Rapeseed Protein.

The objective of this study was to extract the rapeseed protein from by-products and further examine the effect of lab-made rapeseed protein on the droplet size, microstructure, colour, encapsulation and apparent viscosity of emulsions. Rapeseed protein-stabilised emulsions with an increasing gradient of milk fat or rapeseed oil (10, 20, 30, 40 and 50%, v/v) were fabricated using a high shear rate homogenisation. All emulsions showed 100% oil encapsulation for 30 days of storage, irrespective of lipid type and the concentration used. Rapeseed oil emulsions were stable against coalescence, whereas the milk fat emulsion showed a partial micro-coalescence. The apparent viscosity of emulsions raised with increased lipid concentrations. Each of the emulsions showed a shear thinning behaviour, a typical behaviour of non-Newtonian fluids. The average droplet size was raised in milk fat and rapeseed oil emulsions when the concentration of lipids increased. A simple approach to manufacturing stable emulsions offers a feasible hint to convert protein-rich by-products into a valuable carrier of saturated or unsaturated lipids for the design of foods with a targeted lipid profile.

The Effect of Cow Breed and Wild Garlic Leaves (Allium ursinum L.) on the Sensory Quality, Volatile Compounds, and Physical Properties of Unripened Soft Rennet-Curd Cheese.

The aim of this study was to investigate the effects of cow breed and the addition of wild garlic on the sensory quality, volatile compounds, and physical properties of soft rennet-curd cheese. Cheese was produced from the milk of the Polish Holstein-Friesian breed Black-and-White type and the Polish Red breed, with or without the addition of wild garlic leaves. The samples were analyzed for their sensory quality, volatile compounds (using an electronic nose and GC/MS), color, and texture. The intensity of taste and smell characteristics depended only on the addition of wild garlic. PCA showed that the differences in volatile profiles resulted both from the milk cow breed and the use of wild garlic. Breed influenced almost all color parameters, while the addition of wild garlic affected all of them. The milk source, wild garlic addition, and storage duration influenced the majority of the textural parameters of the cheeses. The research conducted indicates that the addition of wild garlic leaves results in the enrichment of the volatile compound profile of cheese, making its taste and smell less milky and sour (p ≤ 0.001), while modifying its color and some textural properties (p ≤ 0.001); while, at the same time, not adversely affecting the sensory assessment of the color, appearance, texture, smell, or taste of the cheese (p > 0.05).

Effect of Bear Garlic Addition on the Chemical Composition, Microbiological Quality, Antioxidant Capacity, and Degree of Proteolysis in Soft Rennet Cheeses Produced from Milk of Polish Red and Polish Holstein-Friesian Cows.

This study aimed to assess the effect of milk source and bear garlic addition on the selected properties of soft rennet cheese. Cheeses were produced from cow milk derived from two sources: Polish Red cows (PR) and Polish Holstein-Friesian cows (PHF) with a 0.5% (w/w) addition of bear garlic (Allium ursinum L.) dried leaves. Chemical composition and fatty acid profiles (GC) were determined in fresh cheeses. Fresh and stored for two weeks cheeses were subjected to microbiological studies, i.e., total aerobic bacteria count (TABC); count of Lactococcus sp., yeast and molds; coliforms; analysis of the proteolysis extension by means of o-phthaldialdehyde (OPA) assay and free amino acids content (HPLC); antioxidant capacity as 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and ferric reducing antioxidant power (FRAP); as well as pH and water activity. Cheeses with bear garlic herbs were more prone to proteolysis but this was not accompanied by any effect on the microbial counts, water activity or pH. Cheeses produced from PR milk contained less monounsaturated fatty acids (MUFA) but were richer in n-3 PUFA and had a lower n-6/n-3 FA ratio than cheeses from PHF milk. Bear garlic addition increased DPPH anti-radical power but had less of an effect on the FRAP values.

Nutritional value and organoleptic assessment of traditionally smoked cheeses made from goat, sheep and cow's milk.

The use of small ruminant milk for smoked cheese production makes it possible to incorporate valuable nutrients into the diet, especially as the consumption of unprocessed sheep or goat's milk is low compared to that from cows. Smoking of food not only prolongs its shelf-life but also improves its flavour. Taking the fact that many consumers do not accept some organoleptic properties of milk from small ruminants into account, the aim of the study was to assess and compare the organoleptic and nutritional properties of traditionally smoked cheeses made from goat, sheep and cow's milk. The analysed cheeses differed in terms of dry matter content and its components such as protein and fat. Their acidity was comparable, except for the sample made of raw goat's milk, which was characterised by a relatively high pH value (6.12 ± 0.06). The highest content of CLA (2.30 ± 0.04%), as well as the highest share of unsaturated and polyunsaturated fatty acids, was determined in the cheese made from sheep's milk. Moreover, the content of butyric and caproic free fatty acids in cheeses made from goat's milk was found to be several times higher than in the other analysed cheeses. The organoleptic assessment did not reveal any significant differences between the cheeses produced at small, private farms and in industrial conditions, or between different types of cheese, regardless of the type of milk from which they were produced.

Probiotic Yoghurts with Sea Buckthorn, Elderberry, and Sloe Fruit Purees.

Elderberries, sea buckthorn, and sloe berries are fruits of wild-grown bushes, valued in folk medicine for their health-promoting properties but still rarely applied in food. The aim of the present study was to produce probiotic yoghurts with a 10% addition of sweetened purees prepared from elderberries (EPY), sea buckthorn (SBPY), and sloe berries (SPY) and to assess their chemical composition, acidity, content of polyphenols and anthocyanins, ferric reducing antioxidant power (FRAP) and antiradical power (ARP), level of starter microbiota, concentration of acetaldehyde and diacetyl, syneresis, instrumentally measured color and texture parameters, and sensory acceptance. The results were compared to those obtained for plain probiotic yoghurt (PPY) and the changes tracked during 1 month of cold storage at 2 week intervals. The addition of elderberry and sloe berries significantly increased the antioxidant capacity of probiotic yoghurts, probably due to a high content of polyphenols, especially anthocyanins. However, anthocyanins were more stable in the EPY when compared to the SPY. All yoghurt treatments were characterized by good sensory quality and viability of starter microorganisms, including probiotic strains during cold storage. Elderberries promoted the evolution of diacetyl in yoghurts during storage and, together with sloe berries, produced increased syneresis and the greatest changes in color profile compared to PPY.

An energy-protein feed additive containing different sources of fat improves feed intake and milk performance of dairy cows in mid-lactation.

This research paper addresses the hypothesis that calcium salts combined with whole linseed and heat-treated rapeseed cake in one feed additive may efficiently stimulate the productivity of dairy cows and have a positive effect on the functional (health-promoting) properties of milk fat. The article proposes the composition of such an additive (EFA) and evaluates its nutritional effect in the diet of mid-lactation dairy cows. Forty multiparous Polish Holstein-Friesian (PHF) dairy cows were allocated to one of four treatments (10 cows/treatment) and fed a TMR diet without EFA or with EFA in the amount of 1, 2 or 3 kg/d per head for a 63-d-period. Individual intake of dry matter (DMI) and nutrients was determined, as was milk yield and composition, including fatty acid profile, fat soluble vitamins, cholesterol and phospholipids (PLs). Irrespective of the treatment group, cows fed diets with EFA had higher (P < 0.05) DMI, milk yield and milk vitamin D3 and K2 concentration but lower (P < 0.01) milk protein, fat and cholesterol contents. The additive did not affect the milk concentrations of ß-carotene or vitamin A or E. The PLs content was correlated with fat concentration in the milk and decreased as the level of EFA in the diet increased. An increase in phosphatidylcholine in total PLs was accompanied by a reduction in the proportion of sphingomyelin (P < 0.05). The use of EFA increased the proportion of polyunsaturated fatty acids (PUFA) in the total fatty acids in the milk. The addition of EFA in the amount of 3 kg increased the proportion of PUFA by 77% (P < 0.05). In conclusion, the use of an energy-protein feed additive (EFA) increases feed intake and milk yield in cows and alters milk fat composition, improving its functional properties. Higher milk production compensates for the decrease in solids concentration in the milk, which has no effect on their daily yield.

Fatty acid profile and oxidation tests of fat extracted from yogurt using rose hip seed oil.

BACKGROUND: Yogurt is a dairy product with a high nutritional value. However, like all milk products, it contains milk fat and is rich in saturated fatty acids. It would be desirable to enrich dairy products in poly- unsaturated fatty acids to increase dietary intake amongst consumers and improve their health. Also, some LAB bacteria are able to produce CLA and CLnA isomers from linoleic and linolenic acids. The aim of this study was to investigate the chemical properties and fatty acid profile of yogurt with the addition of 3.5% of rose hip seed oil. METHODS: Yogurt was made from skimmed milk and yogurt starter culture YC-180 Ch. Hansen (Denmark), with the addition of 3.5% of rose hip seed oil. The peroxide value, acid value, iodine value, TBA rate and fatty acid profile were determined in fat extracted from the yogurt after 1 and 14 days of storage and in fresh rose hip seed oil. The fatty acid profile was determined using gas chromatographic methods with mass spectrometric detectors. RESULTS: Fat extracted from the yogurts had lower levels of peroxides than the fresh oil. It was more acidic and the iodine value was higher than in the fresh oil. Rose hip seed oil enriched the product with polyunsaturated fatty acids. After 14 days of storage, linoleic and linolenic acid levels had increased. Moreover, the content of myristic and palmitic acids had decreased. CONCLUSIONS: The rose hip seed oil added to the yogurt was less susceptible to oxidation. The content of un- saturated fatty acids in the yogurt increased with the addition of the oil, making yogurt with rose hip seed oil an excellent source of Ω-3 and Ω-6 fatty acids. Conjugated linoleic (CLA) and linolenic (CLnA) acids were not detected. However, yogurt manufactured with appropriate adjunct cultures and with the correct oil addition could be a natural source of CLA and CLnA in the human diet.

The suitability of different probiotic strains for the production of fruit-whey beverages.

BACKGROUND: When designing new probiotic products, one of the most important aspects is the selection of bacterial strains with high survival rates in the matrix of the product concerned. The aim of the present research was to evaluate the potential of selected strains of probiotic bacteria for the production of fruit-whey beverages. METHODS: Orange, apple and blackcurrant whey beverages were produced, and each was inoculated with one of the following probiotic strains: Bifidobacterium lactis HN019TM; Lactobacillus aci- dophilus NCFM®; Lactobacillus paracasei Lpc-37TM; Lactobacillus rhamnosus HN001TM. The count of probiotic bacteria as well as pH and total acidity were evaluated at the 1st, 7th, 14th, 21st and 28th day of storage. RESULTS: Beverages containing L. paracasei Lpc-37TM or L. rhamnosus HN001TM were characterized by a sig- nificantly higher average number of viable cells (7.02 or 7.05 log cfu/g, respectively) than products with lactis HN019TM or L. acidophilus NCFM® (6.43 or 6.37 log cfu/g, respectively). The use of L. paracasei Lpc-37 and L. rhamnosus HN001 strains in orange and apple drinks allows the recommended count for probiotic products, 106 cfu/g for 28 days of storage, to be exceeded. Survival of the B. lactis HN019 strain fulfills the above requirements only in the orange drink. The L. acidophilus NCFM® strain was found to be the least suitable for the production of beverages, as it did not reach 6 log cfu/g in any products after 28 days of stor- age. The highest average number of bacteria was found in the orange beverages (7.14 log cfu/g). In terms of bacteria viability, blackcurrant juice was the least suitable for the production of whey probiotic drinks, due to its high acidity. CONCLUSIONS: The results of the present study indicate that careful selection of the fruit juice component, especially in terms of its acidity, is key to designing successful probiotic fruit-whey beverages. Other factors which should be taken into account to ensure a sufficient number of live probiotic cells, i.e. their therapeutic level in fruit-whey drinks, are the choice of probiotic strain and determination of the maximal shelf life.

Influence of milk protein cross-linking by transglutaminase on the rennet coagulation time and the gel properties.

BACKGROUND: Transglutaminase (TGase) modifies milk proteins by cross-linking of caseins, with increased cheese yield being the main technological benefit. In the present work the influence of TGase addition in different concentrations (0, 1, 2 and 3 U g(-1) protein in the system) and under different incubation conditions (0 h, 40 °C/2 h, 25 °C/4 h and 5 °C/16 h) on the rennet coagulation time (RCT) and the comprehensive rennet gel properties were investigated. RESULTS: Modification of milk proteins by TGase in a concentration-dependent manner caused longer RCT and lower gel firmness. The highest TGase concentration and incubation at 40 °C for 2 h resulted in the longest RCT and the lowest gel firmness. Rennet gels obtained from TGase modified milk were characterised by significantly lower values of texture parameters, lower syneresis and were composed of smaller casein micelles, thinner chains and smaller clusters than those obtained from the control milk. The content of whey proteins in the gel from modified milk was higher and the content of individual casein fractions in the milk samples and rennet gels decreased upon TGase modification. CONCLUSION: Rennet cheese with modified textural and nutritional properties and improved yield can be obtained upon TGase modification but simultaneous addition of rennet and TGase is recommended. © 2015 Society of Chemical Industry.