Effect of pretreatments and drying on shrinkage and rehydration kinetics of ginger ( Zingiber officinale )

Self Cite

The current study investigates the effect of microwave (MW), Ohmic heating (OH), and ultrasound (US) pre‐treatments on the extraction of bioactive compounds and the drying kinetics of ginger using a vacuum‐assisted conductive drying system. The US pre‐treatment produced acoustic cavitation, and microstreaming in ginger slices which enhanced the total phenolic content and radical scavenging activity of 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) (i.e., 14.83 ± 0.03 mg GAE/ml and 57.37 ± 0.00%) in obtained aqueous ginger extract (AGE). Similarly, OH pre‐treatment improved the total flavonoids content (i.e., 8.99 ± 0.01 mg QE/ml) of the acquired AGE. The pre‐treatments modified the surface of ginger which eventually led to better moisture diffusivity ratio of 2.58E−08 and 2.01E−08. Furthermore, the GCMS analysis of OH pretreated AGE reported more bioactive compounds compared to MW, US, and control. The major bioactive compounds reported were linalool, neral, geraniol, endo‐borneol, and 2,4 di‐tert‐butyl‐phenol which possess several therapeutic benefits. Thus, the US and OH pre‐treatments effectively enhanced the drying and extraction of bioactive compounds from ginger. Further studies are warranted on the obtained extract to understand its maximum potential for application in food and pharmaceutical industry. Practical applications The ginger extract collected while drying can be used as a flavoring agent or can be incorporated into drinks to enrich the bioactive compounds. The GCMS results indicate that volatile compounds entrapped in the condensate collected contains bioactive components with antioxidant properties. These bioactive compounds can be further studied for their potential health benefits in humans. Thus, this condensate obtained using vacuum‐assisted conductive drying system helps in utilizing the nutrients that are lost and goes unutilized during drying in many industries.

Section: Resultssupporting

confidence: 89%

“…Microwave pre-treatment was carried out using 900 W, 2540 MHz household microwave system (IFB). 100 g of ginger slices was treated at the power level of 360 W for the duration of 5 min (Buvaneswaran et al, 2022). After that, the pretreated samples were kept in the drier system for extraction.…”

Section: Microwavementioning

confidence: 99%

Effect of different thermal and non‐thermal pre‐treatments on bioactive compounds of aqueous ginger extract obtained using vacuum‐assisted conductive drying system

Lakshmipathy

Thirunavookarasu

Kalathil

et al. 2022

Self Cite

“…The color parameters L *, a *, and b * values ( L *–lightness to darkness, a *–redness to greenness, and b *–yellowness to blueness) of millet flour were determined using Hunter lab colorimeter (Colourflex EZ model: 45/0). The color differences (Δ E ) between the WFM flour (WFMF) were calculated using a formula defined by Buvaneswaran et al (2021).

Δ E = \sqrt{{((), L goodbreak- L^{*})}^{2} + {((), a goodbreak- a^{*})}^{2} + {((), b goodbreak- b^{*})}^{2}}

…”

Section: Methodsmentioning

confidence: 99%

Microwave treatment effect on functional and pasting properties, and storage stability of white finger millet

Ananthu¹,

Buvaneswaran

Meena

et al. 2023

Microwave (MW) treatment is a promising technique in cereal processing to improve nutritional quality. The present study investigated the effect of MW power level and exposure time on white finger millet flour (WFMF). Nine different MW treatment combinations were taken based on power level (720 W, 840 W, and 900 W), and exposure time (2 min, 4 min, and 6 min), after the MW treatment the flours are stored at 45 C for 15 days for storage study. The physicochemical, functional, pasting properties, and storage stability of the treated flours were analyzed. According to the results of the study, MW power level and exposure time significantly (p < 0.05) affected the color, swelling power, and water and oil absorption index. The MW treatment reduces the free fatty acid (FFA) and peak viscosity of the samples. The storage study for up to 15 days reveals the changes in color, FFA, and pasting properties of the sample. During storage, the change in FFA content was higher in control untreated flour (CF) than MW treated samples. Due to the structural changes in the starch molecules, the viscosity of MW treated samples was reduced drastically than the CF sample. Results denote that both MW power level and exposure time had a significant effect to alter the functionality and storage stability of WFMF. Practical ApplicationsWhite finger millet (WFM) is the major raw material used for numerous cereal-based products. Microwave (MW) treatments are a novel and promising technology used in cereal processing. A study on changes in finger millet properties under MW treatment helps to improve/alter the functional properties of millet flour, which can be used in new product development. Based on the study, MW treatment significantly improves storage stability by reducing the free fatty acid content, so MW treatment can be used to maintain the quality of the WFM during the storage period to minimize storage losses.

“…Color parameters were determined as described by Buvaneswaran et al (2021) using Hunter Lab Colorimeter (Colorflex EZ model: 4510, Hunter Associates Laboratory, Reston, VA). The CIE laboratory coordinates ( L *, a *, and b *) were directly read with a colorimeter.…”

Section: Methodsmentioning

confidence: 99%

Development of white finger millet probiotic beverage using Lactocaseibacillus rhamnosus (LGG): Process optimization and study of physicochemical and nutritional properties

Buvaneswaran

Sunil

et al. 2022

White finger millet (WFM) is a repository of vital nutrients and minerals. This study aims to develop the white finger probiotic beverage, optimize the ingredients level for the formulation, and study the physiochemical and nutritional properties of the formulated vegan WFM probiotic beverage (WFMPB). The optimum condition for the development of WFMPB was obtained by Box–Behnken design. The independent variable like WFM flour (10–14% w/v), microbial inoculum (1–5% v/v), and sugar (5–15% w/v), and their impact on the response variables like total solid content (TSS), pH, microbial count, and viscosity were studied for optimization. Increment in the amounts of WFM flour and inoculum levels had a significant impact on the microbial load and pH. However, sugar levels affected viscosity and TSS. The combination of 14% WFM, 1% microbial inoculum, and 5% sugar showed maximum desirability of 0.975, with the highest sensory score (8.34), TSS of 15.4 °Brix, pH of 4.33, the microbial load of 9.45 log (cfu/ml) and viscosity of 43.32 cP. WFMPB consists of 11.91% carbohydrates, 1.46% protein, 0.89% fat, and 0.632% crude fiber. The rheological studies showed that WFMPB is a shear‐thinning fluid (n ˂ 0.1). The study revealed that WFM is the better carrier matrix for the LGG growth and can be an alternative for the strict vegan and lactose‐intolerant consumers.