Watermelon juice pretreatment with microfiltration process for obtaining lycopene

Clarification of citrus fruit juices using microfiltration technique equipped with indigenously developed novel ceramic membrane

Microfiltration of citrus fruit juices using membrane technology is a promising method for clarification without losing their inherent properties to extend their shelf life. The present work discusses the development of a tubular ceramic microfiltration membrane and its performance in clarifying two kinds of citrus fruit juices, mandarin and sweet orange. The membrane was prepared by the extrusion method from indigenous bentonite clay, exhibited a porosity of 37% with 0.11 μm pore size, and possessed adequate flexural strength of 18 MPa. The fabricated membrane's potential was evaluated by conducting the tangential filtration of both centrifuged and enzyme-treated centrifuged fruit juices. Also, the applied pressure (68.94-344.7 kPa) and crossflow rate (110-150 Lph) were varied to study the clarified juice properties. At low operating conditions, the highest clarity of the juices was identified despite low permeate flux. The desired properties of juices, including pH, citric acid content, and total soluble solids, were unaffected by pretreatment and tangential membrane filtration, whereas the pectin content, which reduces the juice quality, was eliminated entirely. Furthermore, fouling analysis was carried out using Hermia's models, and cake filtration was identified to be dominant for both juices.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-023-05734-y.

Whole-Genome Resequencing of Near-Isogenic Lines Reveals a Genomic Region Associated with High Trans-Lycopene Contents in Watermelon

Trans-lycopene is a functional phytochemical abundant in red-fleshed watermelons, and its contents vary among cultivars. In this study, the genetic basis of high trans-lycopene contents in scarlet red flesh was evaluated. Three near-isogenic lines (NILs) with high trans-lycopene contents were derived from the scarlet red-fleshed donor parent DRD and three coral red-fleshed (low trans-lycopene contents) recurrent parents. The lycopene contents of DRD (589.4 ± 71.8 µg/g) were two times higher than that of the recurrent parents, and values for NILs were intermediate between those of the parents. Coral red-fleshed lines and F1 cultivars showed low trans-lycopene contents (135.7 ± 18.0 µg/g to 213.7 ± 39.5 µg/g). Whole-genome resequencing of two NILs and their parents and an analysis of genome-wide single-nucleotide polymorphisms revealed three common introgressed regions (CIRs) on chromosomes 6, 9, and 10. Twenty-eight gene-based cleaved amplified polymorphic sequence (CAPS) markers were developed from the CIRs. The CAPS markers derived from CIR6 on chromosome 6, spanning approximately 1 Mb, were associated (R² = 0.45-0.72) with the trans-lycopene contents, particularly CIR6-M1 and CIR6-M4. Our results imply that CIR6 is a major genomic region associated with variation in the trans-lycopene contents in red-fleshed watermelon, and CIR6-M1 and CIR6-M4 may be useful for marker-assisted selection.

Stability enhancement of lycopene in Citrullus lanatus extract via nanostructured lipid carriers

Lycopene is one of naturally occurring carotenoids in plants including watermelon (Citrullus lanatus). Heat, light, and oxygen effect on lycopene isomerization and degradation. Nanostructured lipid carriers (NLCs) are drug delivery system which can enhance the stability of active compound. Therefore, this study aimed to develop watermelon extract loaded in NLCs for lycopene stability improvement. The NLCs were prepared using a hot homogenization technique. Cocoa butter was used as solid lipid. Grape seed oil was used as liquid lipid. Span® 80 and Plantasens® HE20 were used as an emulsifier. The selected unloaded NLCs contained solid lipid to liquid lipid at the ratio of 3:1 and 10% (w/w) of total lipid. The particle size of watermelon extract-loaded NLCs (WH-loaded NLCs) was 130.17 ± 0.72 nm with low PDI and high zeta potential. It also presented high entrapment efficiency. For stability study, the WH-NLC3 could enhance stability and maintain lycopene content after stability test. It exhibited the highest values of lycopene content (83.26 ± 2.30%) when stored at 4°C. It also possessed a prolonged release pattern over 48 hr. Therefore, the NLCs could improve stability and release profile of lycopene from watermelon extract.

Promises and Challenges of Microalgal Antioxidant Production

The exploration of natural antioxidants for nutraceuticals and pharmaceuticals industries has recently increased. This communication aims to grasp the relevance of microalgae in the panorama of natural antioxidant molecules supply to industrial applications as alternatives and/or complements to those typically used from higher plants. Microalgal richness in antioxidant compounds and scavenging ability compared to higher plants is discussed in the context of microalgal biodiversity. We mainly focus on families of powerful antioxidant compounds that have been scarcely investigated in microalgae, such as phenolic compounds, sterols, or vitamins, discussing the promise and challenges of microalgae as providers of health benefits, for instance, through their use as functional food ingredients.

Clarification of purple carrot juice: analysis of the fouling mechanisms and evaluation of the juice quality

Purple carrot juice was clarified by microfiltration. Two modes of filtration, batch concentration and total recycle were tested and the effect of microfiltration process on permeate flux and membrane fouling was studied. Intrinsic membrane resistance was negligible compared with the fouling resistances, which was less than 5 % of total resistance. Determination of membrane hydraulic permeability showed that water cleaning could permit a recovery of about 7 % of initial hydraulic flux. The analysis of color parameters of feed, permeate and concentrate juice during filtration shows that the a* and b* values decrease for the permeate corresponding respectively to changes from green to red and from blue to yellow. The total sugar and reducing sugars increase in permeate and decrease in concentrate. This work showed that it was possible to clarify the purple carrot juice by microfiltration with a real amelioration of the juice appearance.