Effects of pretreatment and spray drying on the physicochemical properties and probiotics viability of Moringa (Moringa oleiferaLam) leaf juice powder

Abstract

Spray drying was investigated in this study to produce Moringa leaf powder which was examined for its nutritional value and ability to support probiotics during storage with and without pretreatment. Response surface methodology with central composite rotatable design was performed to optimize the drying process for maximum yield based on two independent variables: inlet air temperature (116–144°C) and feed maltodextrin concentration (8.0%–22.5% w/w). The responding factors include drying characteristics (yield, color, bulk density, tapped density, water activity, and hygroscopicity) and phytochemical content (total phenolic content, total chlorophyll, and antioxidant activity). Each response was fitted to a model with goodness of fit determined using t test, coefficient of determination (R2), coefficient of variation (CV %), lack‐of‐fit, and signal‐to‐noise ratio. Pretreated and non‐pretreated leaves powder at the optimum settings demonstrated viable (more than 106 CFU/g powder) counts of both Lactobacillus acidophilus and Bifidobacterium lactis up to 28 days after inoculation. Practical applications Spray drying is a proven dehydration technique for heat‐sensitive substance in its atomized liquid form to obtain the counterpart dry powder product without substantial thermal degradation. It is a rapid, cost‐effective, and scalable process for the production of dry powders from vegetable and fruits with superior physical attributes and phytochemical properties as compared to other drying methods. Response surface methodology is a statistical tool that is very useful in the optimization and control of food processes. The information provided in this work will serve as the basis for further study on producing spray‐dried Moringa leaves powder at optimal pretreatment and spray drying conditions. The result is very valuable in considering the different processing variables and product qualities at the same time as compared with single factor experiments. This potentially leads to improved product color and phytochemicals retention while increasing production yield. Positive result shown in the probiotic compatible and viability analysis has revealed that the spray‐dried Moringa leaves powder may find its potential applications in the production of probiotic‐fortified Moringa health products (e.g., food, drink, supplements, and so on) and incorporation into existing food products as a flavoring or coloring targeted at the health food sector.

Lactose‐free skim milk and prebiotics as carrier agents of Bifidobacterium BB‐12 microencapsulation: physicochemical properties, survival during storage and in vitro gastrointestinal condition behaviour

“…For example, De Liz et al (2020) found variations between 0.32-0.33 and 0.54-0.55 g cm −3 , respectively, for loose and tapped bulk densities of spray-dried powders with goat's whey freeze concentrate and inulin, and with only goat's whey freeze concentrate, respectively. Looi et al (2019) found 0.36-0.45 and 0.52-0.64 g cm −3 , respectively, for loose and tapped bulk densities for probiotic spray-dried powders from Moringa oleifera Lam. The change in specific volume between the loose and tapped bulks is recognised as interstitial air content (IA; Wu et al, 2019).…”

Meta analysis on color, total flavonoids, antioxidants, frictional, mechanical, and cutting force of moringa pods

“…Nonetheless, aspect ratio and moisture content imperatively affected the frictional and mechanical properties of moringa. So far, research studies have reported only on changes in quality, nutritional and textural attributes of moringa leaf powder using different drying techniques and various drying temperatures (Premi et al, 2012; Saini et al, 2014; Verma et al, 2015; Looi et al, 2019; Manju et al, 2021), frictional properties of moringa pods (Sudagar et al, 2021), and moisture‐dependent physical properties of moringa seeds (Aviara et al, 2013). There were no investigations on the frictional and mechanical characteristics of moringa pods concerning to aspect ratio and moisture content.…”

Microencapsulation by spray-drying of Manilkara zapota pulp and probiotics (Lactobacillus fermentum A15): Assessment of shelf-life in a food matrix

“…Moreover, from Table 2, a yield of 57.77% obtained by using the spray-drying conditions of this study, is one of the highest values achieved for plant and fruits extractions (da Silva et al, 2019;Looi et al, 2019). About a moisture content of 6.65%, measured on microencapsulated M. zapota pulp, is attributable to hydrophilic groups from MD (Niamnuy et al, 2019).…”