• Interaction of salt content and processing conditions drives the quality response in streaky rashers

      Delgado-Pando, Gonzalo; Allen, Paul; Kerry, Joseph P.; O'Sullivan, Maurice G.; Hamill, Ruth; Department of Agriculture, Food and the Marine; 11F 026 (Elsevier, 2018-07-26)
      Response surface methodology was utilised to explore the relationship between processing conditions, including cooking temperature and drying time, and ingredients in reduced-salt streaky rasher formulations. The goal of this project was to assess the impact of reducing salt content on physicochemical and sensory properties. Salt levels above 2.44 g/100 g did not affect cooking loss. Cooking temperature (240 °C) was negatively correlated with lightness and redness, n-3 fatty acids, and sensory acceptance, and positively correlated with hardness and monounsaturated fatty acids. Salt content was highly correlated with perceived saltiness and both were identified as negative attributes by the sensory panel. Results indicate that optimised reduced-salt streaky rashers with acceptable technological and sensory performance could be achieved under the following conditions: 2 g/100 g salt, 94 min of drying and grilling at 190 °C.
    • Modelling inactivation of Staphylococcus spp. on sliced Brazilian dry-cured loin with thermosonication and peracetic acid combined treatment

      Rosario, Denes K.A.; Bernardo, Yago A.A.; Mutz, Yhan S.; Tiwari, Brijesh K; Rajkovic, Andreja; Bernardes, Patricia C.; Conte-Junior, Carlos A.; Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro; Conselho Nacional de Desenvolvimento Científico e Tecnológico; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior; et al. (Elsevier, 2019-08-26)
      Ultrasound (US) has a high capacity to increase food safety. Although high and/or moderate temperature in combination with US has been studied, the knowledge about cooling/low temperatures as well as its combined effect with chemical preservation methods is scarce. Therefore, the aim of this study was to describe the inactivation of Staphylococcus spp. (SA) present in the natural microbiota of sliced Brazilian dry-cured loin (BDL) using US (40 kHz and 5.40 W/g) at 1.6–17.9 kJ/g, temperature (T) between 6.4 and 73.6 °C and peracetic acid (PA) between 5.5 and 274.5 mg/L employing the Central Composite Rotatable Design. The model fully describes how the combination of US, T, and PA affects SA inactivation. In BDL, an increase in US acoustic energy density (kJ/g) allows the reduction of T necessary to inactivate SA because of the occurrence of synergistic effect. However, US applied at low T was inefficient. On the other hand, PA was more efficient at low T, since high T degraded this compound at different rates according to the holding T. Therefore, the data indicates a relation between the technologies used in the combined decontamination of sliced BDL improving dry-cured meat safety.
    • Optimization of protein recovery from bovine lung by pH shift process using response surface methodology

      Lynch, Sarah A.; Álvarez García, Carlos; O'Neill, Eileen; Keenan, Derek F.; Mullen, Anne Maria; Department of Agriculture, Food and the Marine, Ireland; Teagasc Walsh Fellowship Programme; 11/F/043 (Wiley, 2017-09)
      BACKGROUND Response surface methodology (RSM) was used in a sequential manner to optimize solubilization and precipitation conditions in the recovery of protein from bovine lung using pH shift. RESULTS Separate D‐optimal designs were employed for protein solubilization and precipitation. Independent variables investigated for protein solubilization were time (10–120 min), temperature (4–20 °C), pH (8.0–11.0) and solvent/sample ratio (2.5–10). Variables for protein precipitation were time (0–60 min) and pH (4.25–6.00). Soluble protein yields ranged from 323 to 649 g kg−1 and the quadratic model for protein solubilization revealed a coefficient of determination R2 of 0.9958. Optimal conditions for maximum protein solubility were extraction time 140 min, temperature 19 °C, pH 10.8 and solvent/sample ratio 13.02. Protein precipitation yields varied from 407 to 667 g kg−1, giving a coefficient of determination R2 of 0.9335. Optimal conditions for maximum protein precipitation were pH 5.03 and 60 min. Based on the RSM model, solubilization conditions were manipulated to maximize protein solubilization under reduced water and alkaline usage. These conditions were also validated. CONCLUSION Models for solubilization and precipitation using bovine and porcine lung were validated; predicted and actual yields were in good agreement, showing cross‐species applicability of the results. © 2017 Society of Chemical Industry
    • Optimization of ultrasound-microwave synergistic extraction of prebiotic oligosaccharides from sweet potatoes (Ipomoea batatas L.)

      Guo, Zebin; Zhao, Beibei; Li, Huang; Miao, Song; Zheng, Baodong; FAFU Funds for Distinguished Young Scientists; International Science and Technology Cooperation and Exchange Project of Fujian Agriculture And Forestry University; Science and Technology Project of Fujian Provincial Education Department; xjq201618; KXGH17001; et al. (Elsevier, 2019-03-19)
      In this study, efficient ultrasound–microwave-assisted extraction (UMAE) of prebiotic oligosaccharides from sweet potatoes (Ipomoea batatas L.) was investigated. Response surface methodology was used to optimize the extraction conditions: extraction time, ultrasonic power, and microwave power. The prebiotic effect of extracted oligosaccharides on Bifidobacterium adolescentis was also investigated. The results show that the processing conditions of UMAE for optimum the yields of prebiotic oligosaccharides from sweet potatoes (PPOS4 and PPOS5) and corresponding absorbance (OD) are 100 s extraction time, 300 W ultrasonic power, and 200 W microwave power. Under these conditions, the experimental yields of PPOS4 and PPOS5 and the corresponding OD were 1.472%, 5.476%, and 2.966, respectively, which match the predicted values well. Compared with the conventional hot-water extraction (HWE), microwave-assisted extraction (MAE), and ultrasound assisted extraction (UAE) methods, the UMAE procedure exhibited significantly high extraction efficiency (p < 0.05). Comparison of SEM images of tissues of the sweet potatoes after extractions indicate microfractures and disruption of cell walls in the potato tissues. These results confirm that UMAE has great potential and efficiency in the extraction of bioactive substances in the food and medicinal industries.