Studies on the oxidative changes in meat-based, low-moisture, ready to eat foods are complicated due to complex food system and slow lipid-protein oxidative deterioration. The current study evaluates the oxidative changes over six months of storage on shredded beef and chicken products (locally known as serunding) for physicochemical analysis, lipid oxidation (conjugated dienes and malondialdehydes) and protein co-oxidation (soluble protein content, amino acid composition, protein carbonyl, tryptophan loss and Schiff base fluorescence) at 25 °C, 40 °C and 60 °C. The lipid stability of chicken serunding was significantly lower than beef serunding, illustrated by higher conjugated dienes content and higher rate of malondialdehyde formation during storage. In terms of protein co-oxidation, chicken serunding with higher polyunsaturated fatty acids (PUFA) experienced more severe oxidation, as seen from lower protein solubility, higher protein carbonyl and Schiff base formation compared to beef serunding. To conclude, chicken serunding demonstrates lower lipid and protein stability and exhibits higher rate of lipid oxidation and protein co-oxidation than beef serunding. These findings provide insights on the progression of lipid oxidation and protein co-oxidation in cooked, shredded meat products and could be extrapolated to minimize possible adverse effects arising from lipid oxidation and protein co-oxidation, on the quality of low-moisture, high-lipid, high-protein foods.

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The physicochemical properties, shelf life and stability of pitaya pearls (PP) by reverse spherification from sodium alginate (PP Alginate), kappa carrageenan (PP Kappa) and a combined iota carrageenan-sodium alginate (PP Iota) were studied. The macronutrients of PP were not affected by the hydrocolloid types, except for ash. PP Alginate showed the strongest textural properties. Storage duration affected mainly elasticity of all PP. During storage, PP Alginate and PP Kappa had better morphological and textural stability. However, PP Kappa with lower values of calorie, hardness, and rupture force is the suggested PP for consumption in beverages.

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This study aimed to enhance natural gamma aminobutyric acid (GABA) production in yoghurt by the addition of simple sugars and commercial prebiotics without the need for pyridoxal 5′-phosphate (PLP) cofactor. The simple sugars induced more GABA production (42.83–58.56 mg/100 g) compared to the prebiotics (34.19–40.51 mg/100 g), with glucose promoting the most GABA production in yoghurt (58.56 mg/100 g) surpassing the control sample with added PLP (48.01 mg/100 g). The yoghurt prepared with glucose also had the highest probiotic count (9.31 log CFU/g). Simulated gastrointestinal digestion of this GABA-rich yoghurt showed a non-significant reduction in GABA content and probiotic viability, demonstrating the resistance towards a highly acidic environment (pH 1.2). Refrigerated storage up to 28 days improved GABA production (83.65 mg/100 g) compared to fresh GABA-rich yoghurt prepared on day 1. In conclusion, the addition of glucose successfully mitigates the over-use of glutamate and omits the use of PLP for increased production of GABA in yoghurt, offering an economical approach to produce a probiotic-rich dairy food with potential anti-hypertensive effects.

The objective of the study was to determine the stability of fried fish crackers during storage at different temperatures. The physicochemical properties and lipid stability were examined at 25, 40 and 60°C for three months. Fried fish crackers were packed into two types of packaging with four different layers; (i) polyethylene terephthalate-polyethylene-aluminium-linear low density polyethylene (PET-PE-ALU-LLDPE), and (ii) oriented polypropylene-polyethylene-metallized polyethylene terephthalate-linear low density polyethylene (OPP-PE-MPET-LLDPE). The linear expansion and oil absorption in control fried fish cracker was 75.67 ± 5.86% and 27.86 ± 0.79%, respectively. The initial moisture of cracker ranged from 4.41 to 5.40% and decreased to 2.76 to 3.75%. There were also reductions in water activity of crackers from 0.503 to 0.243. For color, the loss occurred gradually within the storage time from 64 to 47% (L*), from 27 to 19% (b*), and increased from 4 to 9% (a*) due to lipid degradation. For both packaging, the hardness of crackers decreased significantly at 25°C and 40°C, but increased at 60°C. Regardless of temperatures and types of packaging, crispiness increased significantly throughout the storage. This textural changes were possible cause by a decrease in moisture content. The lipid yield of the cracker was not stable within the storage time and the concentration of conjugated dienes and thiobarbituric acid reactive substances (TBARS) showed a gradual increase. These results showed that fried fish crackers in the storage study had undergone lipid oxidation where changes in physical and chemical properties were observed.

The aim of this study was to investigate the effect of chitosan and beeswax as edible coatings on the shelf-life of sapodilla (Achras zapota). The coating formulations used were chitosan only (C), chitosan with 10% beeswax (C + 10B) and chitosan with 20% beeswax (C + 20B). Sapodilla without any coating (WC) was used as a control. The coating formulations, C + 10B and C + 20B had shown to be the best in reducing the senescence of sapodilla as they slowed down the weight loss and breakdown of soluble solids in the fruit, while retaining the firmness and skin colour. Microbial populations of C + 10B and C + 20B were also below permissible microbial food limit (5 log CFU g−1) over the period of 17 days if compared to WC and C, which exceeded the limit. However, C + 10B started to shrivel towards the end of storage. In conclusion, C + 20B showed the best edible coating formulation in extending the shelf-life of sapodilla.

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