Effects of Lacticaseibacillus rhamnosus LOCK900 on Development of Volatile Compounds and Sensory Quality of Dry Fermented Sausages.

Traditional dry fermented meat products are highly appreciated by consumers. A probiotic starter culture increases their attractiveness through sensory qualities and a potential health-promoting effect. The ability to scale the laboratory solution to industrial conditions is an additional scientific and practical value of a new way of using probiotics in the meat industry. The aim was to evaluate the influence of the probiotic starter culture Lacticaseibacillus rhamnosus LOCK900 on the development of volatile organic compounds and the sensory quality of dry fermented pork sausages during fermentation and refrigeration storage. The microbiological and sensory characteristic (QDA method) and volatile compound (gas chromatography coupled with mass spectrometry: GC-MS) were evaluated. The number of LOCK900 cells during 12 weeks of storage remained above 6 log CFU g-1, making this product a functional food. The addition of probiotic LOCK900 increased the levels of acidic volatile compounds, aldehydes, and esters, which, combined with the additives and spices used, had a positive effect on the sensory properties of ripening sausages. The sausages with LOCK900 were characterised by positive sensory features, and their overall quality remained high during storage and did not differ from that of the control sausages.

Fresh Basil Infusion: Effect of Sous-Vide Heat Treatment on Their Volatile Composition Profile, Sensory Profile, and Color.

Herbs, including basil, are used to enhance the flavor of food products around the world. Its potential is influenced by the quality of fresh herbs and processing practices, wherein conditions of heat treatment play an important role. The aim of the research was to determine the effect of sous-vide heat treatment on the volatile compounds profile, sensory quality, and color of basil infusions. The material used for research was aqueous basil infusion prepared conventionally at 100 °C, and using the sous-vide method (65, 75, and 85 °C). The composition of volatile compounds was identified by GC/MS analysis, the sensory profile was assessed using a group of trained panelists, while the color was instrumentally assessed in the CIE Lab system. No significant differences were found in the intensity of the taste and aroma of basil infusions at different temperatures. Seventy headspace volatile compounds were identified in the analyzed samples, ten of which exceeded 2% of relative area percentage. The most abundant compounds were eucalyptol (27.1%), trans-ocimene (11.0%), ß-linalool (9.2%), and ß-myrcene (6.7%). Most of the identified compounds belonged to the terpenes and alcohols groups. Our findings show that the conventional herbal infusion was more like a sous-vide infusion prepared at the lowest temperature SV65, while SV75 and SV85 were similar to each other but different from the conventional. However, a smaller number of volatile compounds in the samples heated at higher temperatures of sous-vide were identified. The sous-vide samples showed a higher content of alkanes. The sous-vide method (p ≤ 0.05) resulted in darker, less green, and less yellow basil leaves than fresh and traditionally steeped ones. Long heat treatment under vacuum at higher temperatures causes a pronounced change in the aroma composition.

Relationship between sensory attributes and volatile compounds of polish dry-cured loin.

OBJECTIVE: The aim of this work was to determine the relationship between objective sensory descriptors and volatile flavour compound composition of Polish traditional dry-cured loin. METHODS: The volatile compounds were investigated by using solid phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS). For sensory assessment, the quantitative descriptive analysis (QDA) method was used. RESULTS: A total of 50 volatile compounds were found and assigned to 17 chemical families. Most of the detected volatile compounds derived from smoking, lipid oxidative reactions and seasoning (46.8%, 21.7%, and 18.9%, respectively). The dominant compounds were: aromatic hydrocarbon (toluene); alkanes (hexane, heptane, and 2,2,4-trimethylpentane); aldehyde (hexanal); alcohol (2-furanmethanol); ketone (3-hydroxy-2-butanone); phenol (guaiacol); and terpenes (eucalyptol, cymene, γ-terpinen, and limonene). Correlation analysis showed that some compounds derived from smoking were positively correlated with the intensity of cured meat odour and flavour and negatively with the intensity of dried meat odour and flavour, while terpenes were strongly correlated with odour and flavour of added spices. CONCLUSION: The analysed dry-cured loins were characterized by specific and unique sensory profile. Odour and flavour of studied loins was mainly determined by volatile compounds originating from smoking, seasoning and lipid oxidation. Obtained results suggest that smoking process is a crucial stage during Polish traditional dry-cured loins production.

Linalool Affects the Antimicrobial Efficacy of Essential Oils.

The high concentrations of essential oils are generally required to receive microbial purity of the products (cosmetics, medicine). On the other hand, their application due to the high concentration of essential oils may be limited by changes in organoleptic and textural quality of the products, as well as they cause irritation and allergies in users. Addition of linalool to essential oil may significantly enhance its antimicrobial effectiveness and reduce their concentrations in products, taking advantage of their synergistic and additive effects. The aim of the study was to compare antimicrobial activity of essential oil alone and in combination with linalool. The antimicrobial activity of the essential oil of Thymus vulgaris, Juniperus communis, Pelargonium graveolens, Citrus bergamia, Citrus grandis, Lavandula angustifolia, Cinnamomum zeylanicum, Melaleuca alternifolia, Syzygium aromaticum, linalool and their combination was investigated against bacteria and fungi using the disc diffusion method. The addition of linalool to S. aromaticum oil in a synergistic manner enhanced its antimicrobial efficacy against P. aeruginosa and A. brasiliensis. Moreover, the additive interaction between this oil and linalool was observed against S. aureus, E. coli and C. albicans. It was also found that linalool in an additive manner increased the antimicrobial effectiveness of T. vulgaris oil against P. aeruginosa. The antimicrobial properties of mixture of essential oils with their active constituents may be used for creating new strategies to maintain microbiological purity of products.

Effects of replacing extracted soybean meal with rapeseed cake in corn grass silage-based diet for dairy cows.

The aim of the study was to assess the effects of partial replacement of soybean meal with a protein-equivalent amount of rapeseed cake in the diet on milking parameters and fatty acid (FA) composition of milk in dairy cows. Two groups of Holstein-Friesian cows, 8 each, consisting of randomised blocks were studied: a control group (C) was given a traditional high-protein supplement (extracted soybean meal) and the experimental group (E), had part of extracted soybean meal replaced with rapeseed cake. Dry matter intake and milk yield in both groups were not affected by the diet but milk fat percentage and yield were decreased in both groups. Rapeseed cake had no effect on milk acidity or on protein (including casein) and lactose contents. A lower concentration of urea in milk in E group indicated a proper ratio of protein to energy in the fodder. Health condition of mammary gland and indicators of metabolic profile were not affected by rapeseed cake supplementation. In E group, the share of atherogenic saturated fatty acids (FA) was reduced after 11 weeks: palmitic, by 26% and myristic, by 22%; moreover, as compared with control cows, the content of monounsaturated FA in milk increased by 44% after 3 weeks and by 68% after 11 weeks, t-18:1 and c-9 t-11 isomer of CLA increased about 2.5-fold after 11 weeks. In E group, the atherogenic index (AI) was significantly (P < 0.001) lower than in C (by 54% on average) and the decrease with time was considerable (by 29%, P < 0.001). Contents of odd- and branched- chain FA in milk were not significantly affected thus reflecting proper rumen function. Partial replacement of soybean meal with rapeseed cake in the diet of cows may improve both milking indices and FA profile of milk.