M Ziarno

Volatile Profile of Non-Fermented Milk and Milk Fermented by BifidoBacterium animalis subsp. lactis

The aim of this work was to determine low-molecular volatile compounds in milk supplemented with the strain Bifidobacterium animalis subsp. lactis Bb-12 with or without fermentation process, stored at 6°C for 4 weeks. The chromatographic analysis of probiotic-supplemented non-fermented milk and milk fermented by strain Bb-12 revealed the presence of volatile compounds, such as ketones, organic acid, and alcohols. The changes in the volatile profile were influenced by fermentation process and/or prolonged cold storage. The fermentative activity of strain Bb-12 and its intensification between the 2nd and 4th weeks were observed in the cold storage condition of milk.

Effects of high pressure treatment on the quality of chicken patties

The effects of high pressure treatment (500 MPa, 10 min, 20 °C) on the quality of commercial chicken patties (breaded and unbreaded) were evaluated. Physical, chemical and microbiological tests were performed 24 h after high pressure processing (HPP), as well as after 14 and 21 days of storage in refrigerated conditions. It was concluded that the use of high pressures extends the shelf life of vacuum-packaged chicken patties by up to 3 weeks, based on the condition of storage during refrigeration. After this period, the number of mesophilic, psychrotrophic and lactic acid bacteria in the pressure-treated patties was five to six logarithmic cycles lower than that in the control products. HPP did not considerably influence the amount of storage drip loss, texture or colour of the patties; however, it quickened the process of lipid oxidation.

Short communication: Incorporation of inulin and transglutaminase in fermented goat milk containing probiotic bacteria

Goat milk is a good carrier for probiotic bacteria; however, it is difficult to produce fermented goat milk with a consistency comparable to that of fermented cow milks. It can be improved by the addition of functional stabilizers, such as inulin, or treatment with transglutaminase. The aim of this study was to determine the effect of cold storage of inulin and microbial transglutaminase on the viability of Lactobacillus acidophilus La-5 and Bifidobacterium animalis ssp. lactis Bb-12 in fermented goat milk. Microbiological analysis included the determination of the probiotic bacteria cell count in fermented milk samples, whereas physico-chemical analysis included the analysis of fat content, titratable acidity, and pH of raw, pasteurized, and fermented goat milk samples. No positive influence of inulin or microbial transglutaminase on the viability of probiotics in fermented goats milk samples was observed. Nevertheless, the population of probiotics remained above 6 log cfu/g after 8 wk of storage at 5 °C.

Effects of milk components and food additives on survival of three bifidobacteria strains in fermented milk under simulated gastrointestinal tract conditions.

Background In the dairy industry, probiotic strains of Bifidobacterium are introduced into the composition of traditional starter cultures intended for the production of fermented foods, or sometimes are the sole microflora responsible for the fermentation process. In order to be able to reach the intestines alive and fulfil their beneficial role, probiotic strains must be able to withstand the acidity of the gastric juices and bile present in the duodenum. Objective The paper reports effects of selected fermented milk components on the viability of three strains of bifidobacteria in fermented milk during subsequent incubation under conditions representing model digestive juices. Design The viability of the bifidobacterial cells was examined after a 3-h incubation of fermented milk under simulated gastric juice conditions and then after 5-h incubation under simulated duodenum juice conditions. The Bifidobacterium strains tested differed in their sensitivity to the simulated conditions of the gastrointestinal juices. Results Bifidobacterial cell viability in simulated intestinal juices was dependent on the strain used in our experiments, and product components acted protectively towards bifidobacterial cells and its dose. Conclusions Bifidobacterial cells introduced into the human gastrointestinal tract as food ingredients have a good chance of survival during intestinal transit and to reach the large intestine thanks to the protective properties of the food components and depending on the strain and composition of the food.

Short communication: Effect of the addition of Bifidobacterium monocultures on the physical, chemical, and sensory characteristics of fermented goat milk

The aim of the study was to use 3 monocultures of Bifidobacterium (Bifidobacterium animalis ssp. lactis AD600, Bifidobacterium animalis ssp. lactis BB-12, and Bifidobacterium longum AD50) in fermented goat milk to assess the microbial, physicochemical, rheological, and sensory quality of beverages during a 3-wk storage period at 5°C. The results indicated that selected bifidobacteria may be used for production of fermented goat milk because they comply with the minimum standards specified by the Food and Agriculture Organization of the United Nations and the World Health Organization during the entire period of storage. However, goat milk fermented by Bif. longum AD50 had less than 106 cfu/g after 21 d of storage. The acidity, acetaldehyde content, viscosity, and hardness of fermented goat milk beverages depended on the strain and the storage period. Sensory properties were similar and acceptable, with a tendency for the quality to be reduced with an extended storage time. Depending on the monoculture of bifidobacteria used to manufacture fermented goat milk, the product had a different pH value. Titratable acidity in all fermented goat milk increased significantly along with the time of storage. Our study has shown that monocultures of bifidobacteria had a significant effect on the content of acetaldehyde, but the lowest effect over the entire storage period was observed in goat milk fermented by Bif. animalis ssp. lactis BB-12. This sample also had the lowest viscosity values compared with other samples and the best organoleptic properties during a 3-wk storage period.

Traditional Polish Curd Cheeses

Curd cheeses have a significant traditional niche in Poland and remain a popular foodstuff. They are a large and diverse group of fermented dairy products. A common feature of all curd cheese is their processing, which is the coagulation of milk protein (mainly casein) by lactic acid fermentation or an acid–rennet combination (a coagulant enzyme simultaneously in conjunction with the lactic acid bacteria). Curd cheeses have mild, clean, slightly acidic taste and smell. Their structure and texture are uniform, compact, without lumps, and slightly loose, and it may be slightly granular. The color of curd cheeses should be white to light cream and be uniform throughout the whole cheese. The application of modern technology and modern methods of curd cheese packaging allows extending the shelf life to 21 days. Curd cheeses are offered in several convenient packages and forms for customers: full-fat, skimmed or semi skimmed, natural, steamed, fried, smoked or flavored, formed in wedge or cubes, sliced or ground, wrapped in parchment paper or plastic wrap, in cups or vacuum packed, with or without sour cream added. The unique role of curd cheese is one of the characteristics that distinguish Polish cuisine from all other.