The Effect of Stunning Methods on Rigor Mortis and Texture Properties of Atlantic Salmon (Salmo Salar)

Shear force and rigor mortis were used to evaluate the post‐mortem changes of muscle texture in Atlantic salmon (Salmo salar). The fish were either stunned with carbon dioxide (CO₂), electricity, or percussion prior to slaughter. The pre‐mortem stress during CO₂ stunning resulted in an earlier onset and resolution of rigor mortis, and accelerated post‐mortem softening of the muscle tissue as compared to the other stunning methods. No significant differences, either in development of rigor mortis or shear force, were seen between fish that were stunned with electricity or by percussion. Consequently electricity can be used for stunning fish prior to slaughter.     

Process conditions affect pigment quality and yield in extracts of purple sunflower hulls

Extract of purple sunflower hulls is a potential red food colorant; however, suitable process conditions must still be identified. Selected process variables were studied using bench-scale units to prepare, clarify, concentrate and spray dry extracts. Concentration by evaporation at 32°C and addition of maltodextrin to 15% (wt/dry wt) prior to drying largely eliminated pigment degradation during those steps. Relative to water extracts, extracts prepared with 5 to 15% ethanol in water generally yielded more pigment with similar levels of degradation and loss during subsequent processing. Use of 5% ethanol/2% citric acid reduced yield by about half relative to water, but gave a powder with a lower degradation index and wetting time. Percentage recovery of pigment during concentration and drying was not greatly affected by solvent type or extraction temperature.     

控制饮用水加氯消毒副产物的研究

试验证明高锰酸钾复合药剂与粒状活性炭联用处理技术是一种高效、经济的除污染技术．能够有效地去除水中有机物，尤其是水中的卤代有机物及其前驱物质．这样就充分保证了饮用水的安全性。     

基于PLC的牲猪屠宰生产线三线同步控制

以牲猪屠宰过程中实现酮体解剖输送线、红脏线和白脏线的三线同步控制为研究对象,采用PLC和变频器组合的控制方案,提出了适于PLC控制、能在三线传动过程中实现高精度稳速控制及同步控制的控制策略,并对系统进行了硬件和软件设计.完全实现了三线准确定位和同步运行,避免了因电机性能差异和三线中负载波动对控制性能的影响.     

生物柴油副产物下层甘油液的组成分析及其分离

分析了菜籽油和大豆油碱催化酯空换法制备生物柴油副产物下层甘油液的主要成份。下层甘油液中主要古甘油、甲醇和脂肪酸皂以及少量的脂肪酸甲酯和游离碱。探索了分离方法。获得的甲醇和脂肪酸可用于生物柴油生产和其它产品的原料，获得的甘油音量达到分析纯要求。     

城市供水消毒中副产物风险与微生物安全性的控制原则

对城市饮用水消毒过程中如何控制消毒副产物对人体健康影响的风险，同时保证水质的微生物安全性提出了三点原则。     

Broccoli leaf powder as an attractive by-product ingredient: effect on batter behaviour,technological properties and sensory quality of gluten-free mini sponge cake

Broccoli by-products, in particular leaves, are rich sources of nutritional and bioactive components thus could constitute a valuable food additive. Although an upsurge in quantity of gluten-free products is observed further studies are required on improvement of their nutritional quality and palatability. This study aimed to investigate the influence of broccoli leaf powder (BLP) on dough behaviour, and technological characteristics and sensory quality of gluten-free mini sponge cake (GFS). Broccoli leaf powder replaced an equivalent amount (2.5%, 5%, 7.5%; w/w) of corn and potato starches in GFS formulation. Applied BLP increased the instrumental firmness of GFS but sensorial attributes (elasticity, crustiness, mastication and adhesiveness) were similar to the control. All broccoli GFS were vividly green, had small size pores properly distributed. Among them, sample with 2.5% BLP was distinguished for its desirable sensory quality, despite a slightly perceived cabbage aroma and taste. Moderate amount of BLP allows to preserve a good quality GFS improving its attractiveness and palatability.     

Modeling the transmission of livestock associated methicillin-resistant Staphylococcus aureus along the pig slaughter line

The study introduces a new approach for a qualitative transmission assessment of MRSA throughout the pig slaughter process. Based on prevalence data found in literature the MRSA contamination and elimination rates of each individual slaughter step were estimated. The rates were used to set up a Monte Carlo simulation for modeling the propagation of MRSA along the process chain and to quantify the impact of a variable initial prevalence on the outcome prevalence of the carcasses. Sensitivity analyses for the model as well as three different scenarios were performed to estimate the impact of cross contamination during slaughter and to determine the process stages where hygiene interventions are most effective.Regardless of the initial extent of MRSA contamination low outcome prevalences ranging between 0.15 and 1.15% were achieved among pig carcasses indicating that the pig slaughter chain generally includes process steps with the capacity to limit carcass contamination. Especially scalding and singeing can lead to a significant reduction of superficial MRSA contamination during the first half of the slaughter process. Nevertheless, scenario analyses showed that the low MRSA outcome prevalence can only be guaranteed if recontamination during the ongoing slaughter process is obviated. In order to ensure a low MRSA load on pig carcasses at the end of slaughter the abattoir should primarily concentrate on controlling the process parameters of scalding and singeing and avoiding recontamination at subsequent process steps.     

Precooked sorghum flour as proper vehicle of ACE-I and DPP-IV inhibitory sorghum peptides

Sorghum flour was heat treated for producing an instant dispersion ingredient. The precooked sorghum flour was added with ACE-I and DPP-IV inhibitory sorghum peptides (3.0 g peptide 100 g⁻¹). The product was reconstituted in water, and peptide bioaccessibility was evaluated by equilibrium dialysis method after simulated gastrointestinal digestion. Total peptide dialysability of precooked sorghum flour added with sorghum peptides was higher than those obtained for precooked sorghum flour (315.9 ± 14.8 vs. 45.2 ± 5.6 µmol, respectively) (P < 0.05). The ACE-I and DPP-IV-IC₅₀ values of the bioaccessible peptides from the bioactive product were lower than those obtained for precooked sorghum flour ingredient (1.04 ± 0.12 vs. 1.82 ± 0.09 and 0.86 ± 0.02 vs. 2.12 ± 0.08 mg protein mL⁻¹, for ACE-I and DPP-IV, respectively) indicating a higher activity. Precooked sorghum flour was a good vehicle since it did not affect the bioaccessibility of ACE-I and DPP-IV inhibitory peptides provided by sorghum protein hydrolysate.