Kinetic study of thermal degradation of flaxseed oil and moringa oil blends with physico-chemical, oxidative stability index (OSI) and shelf-life prediction.

The thermal degradation kinetics of flaxseed oil (FSO) and moringa oil (MO) blends with soyabean oil (SOY; 80%), rice bran oil (RBO; 80%), cotton seed oil (CSO; 80%) and sunflower oil (SFO; 80%) with Rancimat equipment. There was no significant (p ≤ 0.05) difference observed in the specific gravity (SG), density (D), and refractive index (RI) values of the MO and FSO blends, while the rancidity parameters showed the opposite variations. The FTIR spectra showed absorption bands at 966 cm-1, 1097 cm-1, 1160 cm-1, 1217 cm-1, 1377 cm-1, 1464 cm-1, 1743 cm-1, 2945 cm-1, 2852 cm-1 and 3008 cm-1. Oil blends' kinetic degradation (Ea, ΔH, ΔS, A) is represented by the semilogarithmic relationship between the oxidative stability index (OSI) and temperature. The activation energy (Ea) ranged from 77.1 ± 0.21 to 106.9 ± 0.03 kJ/mol and 73.2 ± 0.01 to 104.4 ± 0.02 kJ/mol for flaxseed oil (FSO) and moringa oil (MO) blends, respectively. The enthalpy (ΔH) and entropy (ΔS) ranged from 67.3 to 121.6 kJ/mol, and - 60.2 to - 8.4 J/mol, and 63.55 to 95.59 kJ/mol and - 20.66 to - 4.11 J/mol for FSO blends and MO blends, respectively.

Valorization of pineapple rind for bromelain extraction using microwave assisted technique: optimization, purification, and structural characterization.

Huge amount of waste is generated by the pineapple processing industries which raises concerns regarding its safe disposal into the environment. This ever-increasing problem of waste management can be solved by the valorization of pineapple by-products to high-value compounds. The extraction of proteolytic enzyme, bromelain from pineapple rind using green techniques can help to overcome the drawbacks associated with conventional methods. In the present study, the extraction of bromelain from pineapple rind using microwave assisted technique resulted in considerable amount of proteolytic activity (127.8 U/mL) and protein content (2.55 mg/mL). The optimized extraction conditions were found as 200 W microwave power, 1:5 solid/ liquid ratio and after treatment time of 10 min. Highest specific activity (512 U/mg) of bromelain was obtained after using gel filtration chromatography. FTIR result confirmed the presence of functional groups in bromelain, whereas, XRD analysis indicated the semi-crystalline nature of bromelain. The results indicated MAE as an effective green technique for the extraction of bromelain from pineapple rind. The proteolytic action of the extracted bromelain makes it a suitable functional ingredient for its applications in bakery, dairy, and seafood processing industries.

Biovalorization of mango byproduct through enzymatic extraction of dietary fiber.

Mango is considered one of the most important tropical fruits worldwide in terms of its consumption and consumer acceptability. Its processing generates huge quantities of mango byproducts, which is often discarded unscrupulously into the environment and, therefore, needs effective waste management practices. The extraction of mango peels' dietary fiber using enzymatic method can be a useful valorization strategy for management of mango by-products. In the present investigation, dietary fiber (soluble and insoluble fraction) was extracted by enzymatic hydrolysis using α-amylase, protease, and amyloglucosidase. Highest yield of dietary fiber (67.5%, w/w) was obtained at 60 °C temperature using recommended enzyme concentrations including α-amylase (40 µL), protease (110 µL), and amyloglucosidase (200 µL) after a treatment time of 60 min. SEM analysis indicated the increased porosity of dietary fiber samples caused due to the hydrolytic effect of enzymes on its surface structure, whereas FTIR analysis confirmed the functional groups present in dietary fiber. The coexistence of crystalline and amorphous nature of polymers present in soluble and insoluble fractions of dietary fiber was assessed by XRD analysis. Further, the analysis of functional properties including WHC, OHC, and SC revealed the suitability of using extracted mango peel's dietary fiber in the food systems.

Optimization of ultrasound-assisted enzymatic extraction of resistant starch from green banana peels and its structural characterization.

The global consumption of a large quantity of banana generates a huge quantity of banana peels which creates the problem of its disposal and proper management. The utilization of banana peels for the extraction of resistant starch can be a valuable strategy of waste valorization with economic viability at the industrial level. Green techniques like ultrasound can be efficacious in terms of increasing the extraction efficiency and yield of resistant starch. In this study, ultrasound assisted enzymatic extraction of resistant starch was optimized using response surface methodology. The optimum yield (60.6%) of resistant starch was obtained at 35 °C temperature, 30:1 liquid to solid ratio after a treatment time of 9 min. The results showed that a combination of ultrasound treatment with enzymatic extraction of resistant starch can be an efficient approach for the valorization of banana peels. Resistant starch holds application as a valuable supplement in functional food development in the fields of dairy, bakery, beverages, etc.

Standardization of ultrasound assisted extraction for the recovery of phenolic compounds from mango peels.

Huge amount of mango peels is generated by the mango processing industries with rich composition of phenolic compounds having high antioxidant activity. In the present investigation, ultrasound assisted extraction was found to be an efficient extraction technique for recovery of phenolic compounds. The highest phenolic content was obtained using aqueous solution of ethanol (50%) over other extraction solvents. The highest phenolic content of 35.5 mg GAE/g was obtained using ultrasound assisted extraction method with solid to liquid ratio of 1:30 at 45 °C temperature, ultrasound amplitude 30% after 10 min of treatment time. The highest antioxidant activity of 92% was observed in the mango peels. The significant impact of ultrasonication treatment on the mango peels cell wall is evident from the scanning electron microscopy. The FTIR results indicated the rich composition of polyphenolic compounds present in the mango peels. Ultrasound assisted extraction can prove to be a sustainable green technique with high potential of bioactive compounds recovery like polyphenols for the valorization of mango by-products.