Effect of Added Garcinia Fruit on Total Phenolic Compound Content, Antioxidant Properties and Quality Changes of the Southern Sour Curry Paste, Keang-hleung, during Storage

The favorite soup for Thai particularly in the southern part is Southern sour curry or Keang-hleung soup. The ingredients used in the paste are turmeric rhizome, garlic, shallot and chili. However, for making the sour soup, the souring agent such as lime juice, tamarind pod or garcinia, fruit is added. This study aimed to compare quality changes, total phenolic compound and antioxidant properties of the pastes as affected of added garicia fruit during storage. It was found that the total phenolic compound content of basic paste without the garcinia, garcinia Keang-hleung paste and garcinia Keang-hleung paste without salt decreased as increased storage time. Moreover, the DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity and the ferric reducing power (FRAP) activity of the basic paste without the garcinia decreased as increased storage time. However, the DPPH radical scavenging activity and the FRAP activity of the garcinia Keang-hleung paste with and without salt increased during 2 months of storage period and then decreased as increased storage time. Total viable count (TVC) of all paste samples were in the range of 102 - 103 cfu/g. Yeast and mold counts of basic and garcinia Keang-hlueng paste were less than 30 cfu/g during storage. While, yeast and mold counts of garcinia Keang-hlueng paste without salt were less than 102 cfu/g during storage. Lactic acid bacteria counts of garcinia Keang-hlueng paste were less than 30 cfu/g during storage. While, lactic acid bacteria counts of the basic and garcinia Keang-hlueng paste without salt were less than 102 cfu/g during storage. However, Staphylococcus aureus, Bacilluus cereus, Clostridium perfringens, Salmonella spp., Escherichia coli and coliforms were not detected in all treatments throughout the storage period.

Combined Effect of Garlic Juice and Sa-Tay Marinade on Quality Changes of Oyster Meat during Chilled Storage

Traditionally, meat has been marinated to improve yield, flavor, tenderness, and may increase product shelf life. Sa-tay is a popular dish in Thai restaurant. Physical, chemical, microbiological and sensory qualities after the oyster meat treated with garlic 0, 2 ml of garlic juice then marinated with Sa-tay condiment (8%, wt/wt) were monitored during chilled storage, 4℃ ± 2℃. pH and glycogen content of all treatments decreased while TVB, lactic acid content, ammonia content and K-value increased as storage time. A TBARS, rancidity indicator, of the control was higher compared with other treatments. Mesophilic and lactic acid bacteria of all treatments particularly the oyster treated with the juice increased as storage time increased. However, psychrophilic bacteria, coliforms, fecal coliforms, Escherichia coli, Staphylococcus aureus, Salmonella spp. and Vibrio spp. were low throughout the storage. Consumer acceptability scores of all treatments were higher than borderline (>5) at the end of the storage, 12 days.

Effect of Lipids and Thermal Processing on Antioxidant Activities of Tested Antioxidants and Tom-Kha Paste Extract

The effect of lipids on antioxidant activities of tested antioxidants and Tom-Kha paste extract was determined in the food system. 2,2’-diphenyl-1-picrylhydrazyl (DPPH), 2,2’-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) scavenging activity, peroxide value (PV), thiobarbituric acid reactive substances (TBARS) and p-anisidine value (AV) were methods for determining. The result showed that heating at 121°C for 15 min caused decreasing on DPPH scavenging activity of lauric acid but didn’t affect ABTS scavenging activity of both lauric acid and virgin coconut oil. DPPH scavenging activity of all mixtures was significantly decreased (p p-hydroxycinnamic acid and Tom-Kha paste extract in both lauric acid and virgin coconut oil systems increased after thermal processing. In food systems of lauric acid, PV of almost mixtures except lauric acid-Tom-Kha paste extract 2:1 and lauric acid-Trolox 15:1 was increased after heating. TBARS value of the mixtures was not significantly different (p?≥ 0.05) after thermal processing. AV of only lauric acid-gallic was enhanced after heating. PV of virgin coconut oil added with all tested antioxidant was not changed after heating. TBARS of virgin coconut oil added with antioxidant samples seemed to slightly increase after heating. AV of virgin coconut oil with added gallic acid and Tom-Kha paste extract were not changed by heat treatment while AV of virgin coconut oil with added p-hydroxycinnamic acid and Trolox seemed to decrease after heating.