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Malaysia produces varieties of tropical fruits such as durian, rambutan, jackfruit, mango, papaya, and mangosteen but the seeds are considered waste. The seeds contain beneficial nutrients such as protein, carbohydrates, fat, and minerals, and have high bioactive properties. Various processing methods have been applied to extract the seeds and apply them to the food system. The information is scattered and incomprehensive, therefore, this paper aims to review the chemical properties and biological activities of the selected tropical fruit seeds, and their processing and functional properties to the food. Most seeds are rich in carbohydrates but also contain various minerals and fatty acids. The antioxidant, antidiabetic, anti-bacterial/anti-fungal, anti-inflammatory, anti-hyper cholesterol and anti-proliferative properties were also reported with rambutan and papaya seeds having the most bioactive properties. Novel and conventional extraction methods of the seeds, the functionality of the seeds to improve the food such as pasting and emulsifying properties, and their effect on the colour, texture, sensory and storage stability were also highlighted. In summary, all the selected seeds have the potential to be upcycled as food ingredients as they contain various nutrients while providing therapeutic and functional properties, however, further research can be considered to optimize the seeds' usability. [ABSTRACT FROM AUTHOR]

Abstract: The study aims to investigate the effect of repetitive ultraviolet irradiation (UV–UV) and the combination effect with dimethyl dicarbonate (UV–DMDC–UV) on the physico-chemical properties and microbiological stability of pineapple juice. UV dosages of 10.76mJ/cm2 percycle and 250ppm of DMDC were used. There was a significant decrease in turbidity, total phenolic and vitamin C in the treated juices. The UV–UV reported a significant reduction of 1.91logCFU/ml in total plate count and 1.4logCFU/ml in yeast and mould. Post addition of DMDC into the UV irradiated juice (UV–UV–DMDC) showed reductions of 2.61logCFU/ml for TPC and 4.87logCFU/ml for YM. This study demonstrated the effectiveness of UV irradiation in preserving the nutritional quality and the addition of DMDC can have a combination effect with the UV irradiation of juice in terms of microbial reduction. However, the treatments were not sufficient to achieve adequate microbial reduction as required by the FDA. Industrial relevance: Dimethyl dicarbonate (DMDC) is one of the effective anti-microbial agents that can control a wide range of microorganisms which includes Escherichia coli 0157:H7 and yeast. The effect of dimethyl dicarbonate (DMDC) in reducing microbial counts was significant in this study. According to Threlfall and Morris (2002), DMDC is used to prevent fermentation in excessive yeast contamination in wine production. Moreover, Halim et al. (2012) stated that DMDC has shown promising results for microbial inactivation of fruit juices in a preliminary study in lab. Therefore, combination effect with additives (DMDC) may be able to increase the efficiency of the UV irradiation for microbial reduction in juice and longer the shelf life of juice. [Copyright &y& Elsevier]

Chili shrimp paste (CSP) is an exotic traditional Southeast Asian condiment prepared using mainly fresh chilies and fermented shrimp paste ( belacan ) which attributed to strong pungent fishy odor. This study aims to evaluate the effectiveness of electron beam irradiation (EBI) exposure on CSP for microorganisms decontamination, and its physicochemical qualities changes. Changes in capsaicinoid contents and volatile compounds were analyzed using HPLC and GC–MS. Mesophilic bacteria, yeast, mold and pathogenic Enterobacteriaceae decreased as irradiation dose increasing from 0 to 10 kGy. EBI at 10 kGy effectively decontaminated the samples with no significant effects on phenolic and capsaicinoids contents compared to the fresh samples. From 24 compounds, irradiated CSP retained 23 volatile compounds, while thermally treated CSP has only 19 compounds. EBI at 10 kGy is effective for decontamination in CSP with lesser destructive effect on volatile compounds and texture compared to thermal treatment. [ABSTRACT FROM AUTHOR]

Pectin from different fractions of dragon fruit ( Hylocereus polyrhizus ) peel was extracted using 1% citric acid and the physico-chemical characteristics of the pectin were studied. The highest pectin yield (26.38% on dry weight basis) was obtained from fresh inner layer of the peel when extraction was carried out at temperature: 73 °C, time: 67 min, pH: 2.03, and sample to citric acid ratio: 1:4 (w/v). The pectin also demonstrated the highest degree of esterification (63.74%) when compared with pectin from other fractions of the dragon fruit peel investigated in this study. The calculated degree of esterification confirmed that the extracted pectin is a high methoxyl pectin. The molecular weight of the pectin determined using size exclusion chromatography was 0.88 × 10 5 Da. Monosaccharide composition determined using high performance liquid chromatography revealed that the pectin was predominantly constituted of galacturonic acid (39.11%), followed by moderate concentrations of mannose, rhamnose, galactose, glucose and minor amounts of xylose and arabinose. The pectin exhibited Newtonian behaviour at concentrations of 0.5% and 1.0%, and pseudoplastic behaviour at concentrations of 2.0% and 3.0%. Although the viscosity of the dragon fruit peel pectin was lower than that of commercial apple and citrus pectins, it can be used as a functional and health ingredient in low viscous foods and beverages. [ABSTRACT FROM AUTHOR]

Highlights: [•] Edible coatings were used for fresh-cut pineapple during low temperature storage. [•] Alginate-based coating incorporated with 0.3% lemongrass was the best formulation. [•] This formulation has potential to extend the shelf life and maintain the quality. [•] Lemongrass (0.5%) had negative effect on taste and firmness of coated samples. [ABSTRACT FROM AUTHOR]