Showing papers in "Asian Journal of Food and Agro-Industry in 2013"

Consumer perception on safety and sensory evaluation of street-vended pork Dim Sum (Siomai)

Abstract: Street food often reflects traditional local cultures and offer a unique cultural experience to tourists and even to ordinary consumers. With the increasing pace of globalization and tourism, the safety of street food has become one of the major concerns of public health. A survey had been performed to determine why are the consumers buying street food and what do they consider in buying these. This study showed that 44% of the students surveyed considered food safety as one of the criteria in buying street food. To assess food safety, microbiological analysis has been performed which showed that organisms such as coliforms and S. aureus at high levels are present in one of the samples. Sensory evaluation was also performed to determine the preference of the consumers in terms of its odor, appearance and overall acceptability.

Effects of extraction methods and heat treatment on total phenolic compounds and antioxidant activity in juice extracted from the Australian-grown 'wonderful' pomegranate

Abstract: Physicochemical properties of the Australian-grown 'Wonderful' pomegranate juice (WPJ) including total phenolic compounds (TPC) and antioxidant activity (AA) were determined and compared with four different brands of imported pomegranate juices (IPJs). The TPC in WPJ was found to be 2,400 ± 200 mg/L gallic acid equivalent (GAE) while in the IPJs it ranged from 1,000 to 2,800 mg/L GAE. The AA of WPJ was 11.0 ± 1.0 mM/L Trolox equivalent antioxidant capacity (TEAC) while in IPJs it ranged from 5.5 to 14.5 mM/L TEAC. To facilitate consumer access to the health benefits of pomegranate, a probiotic product was developed from bovine milk supplemented with different levels of IPJ. Maximum IPJ supplementation level in heat-treated milk with no adverse effects on yogurt attributes was found to be 20% (V/V), resulting in maximum TPC level of 731 ± 69 mg/L GAE in probiotic yoghurt.

Comparison of the mitragynine content of aqueous extracts from Mitragyna speciosa Korth leaves from two different geographical areas in Malaysia.

Abstract: It was interesting to find that the concentration of mitragynine in aqueous extracts of MitragynaspeciosaKorthleaves (ketumleaves) from both Penang and Kedah States of Malaysia was merely0.10 µgml -1 and 0.09µgml -1 respectively. There was significant difference observed between the freeze dried yields obtained and the aqueous extracts from Kedah and Penang, 124.0 mg / 60 ml and 262.5 mg/60 ml respectively. Both the aqueous extracts shared the same chemical profile under GCMS chromatogram and contained at least two isomers with 9-methoxy group.

Mixed culture fermentation with Rhizopus oligosporus and Micrococcus luteus to enhance isoflavone aglycone, factor 2 production and antioxidant activity of soybean

Abstract: In this study, mixed culture fermentation of soybean under solid-state fermentation using R. oligosporus and M. luteus was performed. M. luteus was inoculated at different times of fermentation process, together with R. oligosporus at the beginning and after 6 h, 12 h, 24 h and 36 h fungal fermentation. The methanolic extracts of soybeans were analyzed using HPLC and subjected to free radical scavenging activity measurement using DPPH method. The results of HPLC analysis showed that inoculating M. luteus after 24 h fungal fermentation increased total isoflavone (daidzein, genistein, factor 2) concentration by 69.69% to highest level. The amount of daidzein, genistein, and factor 2 increased to 739,165 µg (75.74%), 805,855 µg (69.99%) and 91,542 µg (31.22%) per gram of defatted soybean powder respectively after 48 h. M. luteus inoculation at 0 h, 6 h, 12 h, 24 h, and 36 h of fermentation process increased the soybean free radical scavenging activity to 64.28%, 65.03%, 77.54%, 57.81% and 82.55%, respectively. This study shows that inoculation time of M. luteus plays an important role in the production of daidzein, genistein and factor 2 at the end of soybean fermentation and affects free radical scavenging activity of soybean.