Texture Modification Technologies and Their Opportunities for the Production of Dysphagia Foods: A Review

Dysphagia or swallowing difficulty is a common morbidity experienced by those who have suffered a stroke or those undergone such treatments as head and neck surgeries. Dysphagic patients require special foods that are easier to swallow. Various technologies, including high‐pressure processing, high‐hydrodynamic pressure processing, pulsed electric field treatment, plasma processing, ultrasound‐assisted processing, and irradiation have been applied to modify food texture to make it more suitable for such patients. This review surveys the applications of these technologies for food texture modification of products made of meat, rice, starch, and carbohydrates, as well as fruits and vegetables. The review also attempts to categorize, via the use of such key characteristics as hardness and viscosity, texture‐modified foods into various dysphagia diet levels. Current and future trends of dysphagia food production, including the use of three‐dimensional food printing to reduce the design and fabrication time, to enhance the sensory characteristics, as well as to create visually attractive foods, are also mentioned.     

Comparative evaluation of the effect of microfluidisation on physicochemical properties and usability as food thickener and Pickering emulsifier of autoclaved and TEMPO-oxidised nanofibrillated cellulose

Although chemical-free production processes of nanofibrillated cellulose (NFC) have been investigated, comparative studies on the effect of chemical and chemical-free processes to produce NFCs are limited. Combined effect of either of these production routes and defibrillation condition has also never been studied. Here, thermally treated NFCs were produced through microfluidisation for 6–12 passes (ANFC6-ANFC12), while TEMPO-oxidised NFC (TONFC) was prepared at six passes. Proportion of nanocellulose, viscosity, Gʹ and Gʺ values increased with increased microfluidisation pass in the cases of ANFCs. ANFC12 exhibited gel-like behaviour with strongest three-dimensional network structure and required lowest concentration to enhance thin liquid foods into honey-like consistency. TONFC needed to be added by as much as 8.5, 1.3 and 2.3 times the amount of ANFC12 to achieve the same consistency in thickened water, milk and soup, respectively. ANFC12 can also be well used as Pickering emulsifier due to its higher viscosity and gel-like property.     

Effect of pretreatments and vacuum drying on instant dried pork process optimization

Dehydrated meat which can be instantly rehydrated is needed by the industry. This research was aimed to investigate a more economical drying process. Central composite design was applied with three variables: cooking pressure, cooking time, and vacuum drying temperature. The responses were shear force (N), work of shear (N.mm) and % rehydration. The multiple linear regression equation models could predict 91.7, 90.9 and 94.8% of each response, respectively. Cooked pork meat was used for target responses. Its maximum shear force was 43.39±5.42 N, and work of shear was 419.50±64.17 N.mm. Vacuum drying temperature highly affected all responses. Validation of the predicted data was done using two optimum conditions. First condition was cooking pressure of 21.6 lb/in.(2), cooking time of 50 min, and vacuum drying temperature of 95°C. The second condition was cooking pressure of 38.4 lb/in.(2), cooking time of 35 min, and vacuum drying temperature of 100°C. A t-test confirmed that the observed data were not statistically different from the predicted data.     

Effect of acid,heat and combined acid-heat pretreatments of anaerobic sludge on hydrogen production by anaerobic mixed cultures

Activated sludge (AS) from wastewater treatment plant of brewery industry was used as substrate for hydrogen production by anaerobic mixed cultures in batch fermentation process. The AS (10% TS) was pretreated by acid, heat and combined acid and heat. Combined acid- heat treatment (0.5% (w/v) HCl, 110 °C, 60 min) gave the highest soluble COD (sCOD) of 1785.6 ± 27.1 mg/L with the highest soluble protein and carbohydrate of 8.1 ± 0.1 and 38.5 ± 0.8 mg/L, respectively. After the pretreatment, the pretreated sludge was used to produce hydrogen by heat treated upflow anaerobic sludge blanket (UASB) granules. A maximum hydrogen production potential of 481 mL H₂/L was achieved from the AS pretreated with acid (0.5% (w/v) HCl) for 6 h.     

Enhanced bio-hydrogen production from sugarcane juice by immobilized Clostridium butyricum on sugarcane bagasse

Immobilized Clostridium butyricum TISTR 1032 on sugarcane bagasse improved hydrogen production rate (HPR) approximately 1.2 times in comparison to free cells. The optimum conditions for hydrogen production by immobilized C. butyricum were initial pH 6.5 and initial sucrose concentration of 25 g COD/L. The maximum HPR and hydrogen yield (HY) of 3.11 L H₂/L substrate·d and 1.34 mol H₂/mol hexose consumed, respectively, were obtained. Results from repeated batch fermentation indicated that the highest HPR of 3.5 L H₂/L substrate·d and the highest HY of 1.52 mol H₂/mol hexose consumed were obtained at the medium replacement ratio of 75% and 50% respectively. The major soluble metabolites in both batch and repeated batch fermentation were butyric and acetic acids.