Stefansencooley4728

The aim of this study was to compare the water-soluble low molecular weight (WLMW) compounds and fatty acids (FAs) in raw meat and chicken soup between the two Chinese native chickens (Wuding chicken and Yanjin silky fowl chicken) and one typical commercial broiler (Cobb chicken). The WLMW compounds of chicken meat was studied using 1H nuclear magnetic resonance spectroscopy (1H NMR) and the FAs were identified and quantified using gas chromatography-mass spectrometry (GC-MS). Compared with typical commercial broiler, the main flavor substances (WLMW compounds and FAs) content were significantly higher in the breast and leg meat of the two Chinese native chickens (P less then 0.05). Instead, the content of main flavor compounds was significantly higher in chicken soup of typical commercial broiler (P less then 0.05). These results contribute to a further understanding the distinction of the flavor compounds between the typical commercial broiler and Chinese native chickens, which could be used to help assess the meat quality of different local broilers.The impact of free wheat flour lipids on air-liquid interface stability during sponge cake making was investigated. Therefore, the molecular population at the air-liquid interface in batters prepared with flour of which part of the lipids had been either relocated or removed prior to batter preparation was determined. Surface-active molecules were isolated from batter using a foam separation protocol. Diluted batter was whipped and the resulting foam was used as model system for the air-liquid interface in sponge cake batter. Relocating flour lipids prior to batter making enabled them to adsorb at the air-liquid interface in the foam. This limited the degree of protein adsorption at the air-liquid interface, but it did not impact the composition of the adsorbed protein population. Removing flour lipids prior to batter making resulted in foam containing relatively higher levels of lipids mainly originating from egg yolk. Prior removal of flour lipids impacted neither foam protein content nor foam protein composition. The resultant molecular population improved air-liquid interface stability in sponge cake batter. Thus, free wheat flour lipids and wheat flour lipids set free by solvent treatment decrease air-liquid interface stability in sponge cake batter mainly because they limit protein adsorption and, as such, interfere with the protein-dominated interface.Cross protection is a widely existed phenomenon in microorganisms which subjected to a mild stress develop tolerance to other stresses, yet the underlying mechanisms for this protection have not been fully elucidated. Here, we report that heat preadaptation induced cross protection against acid stress in Tetragenococcus halophilus, and the cross protective mechanisms were revealed based on cell surface characterizations and transcriptomic analysis. The results showed that heat preadaptation of T. halophilus at 45 °C for 1.5 h improved the acid tolerance of cells at pH 2.5, and the preadapted cells exhibited higher pHi compared with the un-preadapted cells during acid stress. Analysis of the cell surface properties suggested that the heat-treated cells displayed smoother surface, lower roughness and higher integrity than those of untreated cells. Meanwhile, the distributions of membrane fatty acids also changed in response to acid stress, and the treated cells reveled lower ratio of unsaturated to saturated fatty acids. RNA-Sequencing was employed to further elucidate the cross protective mechanism induced by heat preadaptation, and the results showed that the differentially expressed genes (DGEs) were mainly involved in cellular metabolism and membrane transport during heat preadaptation. A detailed analysis of gene expression profile of cells between heat treated and untreated revealed that genes associated with energy metabolism, amino acid metabolism and genetic information processing were induced upon heat stress. Results presented in this study may broaden our understanding on cross protection and provide a potential strategy to enhance the performance of cells during industrial processes.Salmonella is one of the most common causes of foodborne diseases and can cause severe economic loss. selleck chemical Increased antibiotic resistance, particularly of multidrug-resistant strains, has led to the use of phages as substitute agents. However, bacteriophages are usually sensitive to harsh environments. At present, microencapsulation is one of the methods to solve this problem. But there are few studies on the application of microencapsulated bacteriophages in food matrix. In this study, a novel Salmonella phage T156 was firstly studied for its biological characteristics. T156 belongs to the T5-like Siphoviridae family, with broad host spectrum and potent lytic ability against tested Salmonella strains, including multiple antibiotic-resistant Salmonella. It also showed valuable characteristics such as high pH (3.0-12.0), thermal tolerances (30-50 °C) and a short latent period (10 min). Genome analysis indicated T156 genome comprised a 123,849 bp DNA with 176 putative open reading frames, of which 56 ORFs were annotated to known functions. No genes associated with antibiotic resistance, virulence factor and lysogeny were found in T156 genome. Then, orifice-coagulation bath method was used to microencapsulate bacteriophage T156. Microencapsulated bacteriophage can effectively inhibit the growth of Salmonella in artificially contaminated milk and lettuce at 4 °C and 25 °C. At 25 °C, the maximum antibacterial efficacy of phage in milk and lettuce were 57.93% and 55.47%, respectively. This is the first report about microencapsulated bacteriophage infecting Salmonella in food matrix. It can provide insights into fundamental researches on microencapsulated bacteriophage for future utilization in food.Food safety is often based on the application of several preservative (hurdle) factors whose combination must be smartly selected. The aim of the present study was to evaluate the effect of lactate and diacetate on the high pressure processing (HPP) inactivation of three L. monocytogenes strains (CTC1011, CTC1034 and Scott A) in sliced cooked ham. Inoculated vacuum-packed slices of cooked ham formulated without organic acids and with lactate, diacetate or the combination of both were pressurized at 400 MPa for different holding times and the inactivation kinetics were characterised by fitting primary and secondary models. The shape of the inactivation curves for L. monocytogenes depended on both product formulation and strain. Interestingly, lactate caused a dose-dependent piezo-protection in all three strains, as the HPP inactivation rate decreased in cooked ham formulated with increasing amounts of lactate and in comparison with the control product. The design, validation and implementation of HPP requires a tailor-made approach, considering product formulation and selection of strain/s.Traditionally preserved meat products are common food items in Sikkim state of India. We studied the high-throughput sequencing of four traditionally preserved meat products viz. beef kargyong, pork kargyong, yak satchu and khyopeh to profile the bacterial communities and also inferred their predictive functional profiles. Overall abundant OTUs in samples showed that Firmicutes was the abundant phylum followed by Proteobacteria and Bacteroidetes. Abundant species detected in each product were Psychrobacter pulmonis in beef kargyong, Lactobacillus sakei in pork kargyong, Bdellovibrio bacteriovorus and Ignatzschinera sp. in yak satchu and Lactobacillus sakei and Enterococcus sp. in khyopeh. Several genera unique to each product, based on analysis of shared OTUs contents, were observed among the samples except in khyopeh. Goods coverage recorded to 1.0 was observed, which reflected the maximum bacterial diversity in the samples. Alpha diversity metrics showed a maximum bacterial diversity in khyopeh and lowest in pork kargyong Community dissimilarities in the products were observed by PCoA plot. A total of 133 KEGG predictive functional pathways was observed in beef kargyong, 131 in pork kargyong, 125 in yak satchu and 101 in khyopeh. Metagenome contribution of the OTUs was computed using PICTRUSt2 and visualized by BURRITO software to predict the metabolic pathways. Several predictive functional profiles were contributed by abundant OTUs represented by Enterococcus, Acinetobacter, Agrobacterium, Bdellovibrio, Chryseobacterium, Lactococcus, Leuconostoc, Psychrobacter, and Staphylococcus.The effects of partial NaCl substitution combined with high-temperature ripening on the proteolysis and formation of volatile compounds in dry-cured lamb ham was investigated. Two salt treatments, I (0% KCl + 100% NaCl) and II (25% KCl + 75% NaCl), were considered. Although some studies have analyzed the influences of salt substitution on volatile compounds of dry-cured ham, no studies have evaluated lamb ham produced in China. Intensifying the high-temperature ripening lead to an increase in the formation of flavors generated by the Maillard reaction and Strecker degradation in both treatments, also, had a positive influence on proteolysis index and content of total free amino acids during the ripening stage. The application of 25% KCl did not influence the formation of volatiles during curing stage, however, there were more volatiles came from amino acids degradation in the final products with 25% KCl. Therefore, sodium reduction combined with high-temperature ripening may be an alternative method to manufacture Chinese dry-cured lamb hams.In recent years, a decreasing trend in fruit consumption has been detected in Mediterranean countries, with the consequent risk for the population's health. The objective of this study was to obtain consumer knowledge that can be useful to promote fruit consumption by designing specific interventions. This study was conducted in Spain as its inhabitants have traditionally adhered to the Mediterranean diet. Firstly, four fresh fruit types were identified based on the consumer perception of the fruit characteristics that condition the eating process (fruit size, the need for cutlery to peel/eat fruit, and susceptibility to be spoiled during transportation). Then consumer perception of situational appropriateness of six different fruit types (the 4 types of fresh fruit previously identified, dehydrated non-traditional fruit (DF), and fresh-cut fruit ready to eat on the go (FCF)) was investigated by the Item-By-Use method using Check-All-That Apply (CATA) questions. The potential of DF and FCF to broaden fruit consumption situations, and barriers for their consumption, were evaluated. Fresh fruits, particularly 'easy-to-peel' ones like mandarins or bananas, were those preferred by consumers in most evaluated contexts. DF were considered mainly appropriate to be consumed 'As an ingredient' and 'As a healthy snack', while FCF were more suitable 'To be included in school lunchboxes' and 'To eat immediately'. According to our results, these two processed fruit types can help to increase the fruit consumption of a non-negligible percentage of the population (38% of participants), but it is necessary to overcome the barriers related mostly to sensory properties, plastic packaging and consumer misperception of fewer healthy properties compared to fresh fruit.