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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.

This study aimed to produce sourdough bread using an encapsulated kombucha sourdough starter culture without the addition of baker's yeast. The bioactive metabolites of kombucha sourdough starter and sourdough starter without kombucha were identified using 1H‐NMR analysis with multivariate analysis. The physical properties, including loaf volume, specific loaf volume, firmness, and water activity were determined following standard methods. The shelf life and consumer acceptability of the bread were also being evaluated. The principal component analyses showed the presence of 15 metabolites in kombucha sourdough starter. The major compounds that contributed to the differences from sourdough starter without kombucha were alpha‐aminobutyric acid, alanine, acetic acid, riboflavin, pyridoxine, anserine, tryptophan, gluconic acid, and trehalose. The encapsulated kombucha sourdough starter increased the loaf volume (976.7 ± 25.2 mL) and specific loaf volume (4.38 ± 0.12 mL/g) compared to yeast bread. Thus, significant (P < 0.05) reduction was observed in the crumb firmness (116.07 ± 6.28 g) compared to traditional sourdough bread and yeast bread. The encapsulated kombucha sourdough starter extended the shelf life of bread by 5 to 10 days at room temperature. The sourdough bread prepared using the encapsulated kombucha sourdough starter demonstrated significantly (P < 0.05) higher taste and overall acceptability scores compared to the other bread. The findings indicate that the encapsulated kombucha sourdough starter is promising to produce functional sourdough bread with extended shelf life and improved quality. Practical Application Encapsulated kombucha sourdough starter culture that appropriately refreshed can be used primarily as a dough leavening agent in the bread industry without the addition of baker's yeast. This starter culture applied in sourdough bread production extended the shelf life and improved the biological function of sourdough bread.

Dietary fiber (DF) has wide applications, especially in the food and pharmaceutical industries due to its health-promoting effects and potential techno-functional properties in developing functional food products. There is a growing interest in studies related to DF; nevertheless, there is less focus on the fractionation and characterization of DF. The characteristics of DF fractions explain their functionality in food products and provide clues to their physiological effects in food and pharmaceutical industrial applications. The review focuses on a brief introduction to DF and methods for its fractionation. It discusses the characterization of DF in terms of structural, physicochemical and rheological properties. The potential sources of DF from selected defatted oilseeds for future studies are highlighted.

The interest in fruit and vegetable juices production has increased significantly all over the world due to their benefit value, quality of production and increasing of consumer awareness and preference for healthy food. The production of sugar palm (Arenga pinnata) fruit juice with exotic characteristics has the potential to be explored based on the new technologies and methods in juices industry. In beverage industry, enzyme is an essential tool for quality improvement and cost saving by increasing the yield of the fruit juice. The purpose of this study is to determine the effects of different enzymatic treatment on sugar palm fruit juice processing. Sugar palm fruit purees were treated individually and in combination using two types of commercial enzymes: Novozymes Cellulase and Pectinex Ultra SP-L at a concentration of 0.05% (w/w) and incubated at 45°C for 60 min. The results showed that there are significant (p<0.05) reduction on proximate content such as crude fibre, crude protein and carbohydrate for the enzymes treated juices as compared to the untreated juice. The enzyme treatment also significantly (p<0.05) reduced the juice viscosity and ascorbic acid content, promoted juice clarification and increased L value, yield, TSS and sugar content. In conclusion, the quality of sugar palm fruit juice can be improved by using the combination treatment of pectinase and cellulase enzymes.

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.