Effect of thermal packaging temperature on Chinese steamed bread quality during room temperature storage

Starch retrogradation in starch-based foods: Mechanisms, influencing factors, and mitigation strategies

Starch-based foods are the most common foods in the daily diets. However, starch-based foods are prone to starch retrogradation, resulting in texture hardening, taste deterioration and nutrient loss. This paper reviewed the mechanisms and the influencing factors of starch retrogradation in starch-based foods, and the strategies to mitigate it. The core mechanisms and influencing factors of starch retrogradation are analyzed in depth, and various methods to alleviate it are summarized. Starch retrogradation is mainly caused by recrystallization of amylose and amylopectin, accompanied by moisture migration and rearrangement of starch molecules. The amylose to amylopectin ratio, moisture content, protein and lipids are intrinsic factors. At the same time, processing methods and storage temperatures are extrinsic conditions that significantly affect the rate and extent of starch retrogradation. Effective measures to alleviate starch retrogradation include the addition of food ingredients and exogenous substances, the optimization of processing methods and storage conditions, as well as the application of edible coatings. This review aims to summarize the latest progress in delaying aging of starch-based foods, enhance the understanding of starch retrogradation mechanisms, and promote the development of starch-based foods with longer shelf lives, thereby providing scientific basis and technical support for the food industry.

Effects of cereal flour types and sourdough on dough physicochemical properties and steamed bread quality

Coarse cereals have been promoted for their health benefits, and sourdough is used to improve their steamed bread sensory acceptance. However, grains vary in dough physiochemical properties and steamed bread-making performance. This study investigated the effects of yeast and sourdough fermentation on the biochemical, textural, and flavor properties of dough and steamed bread of eight grain types. Results indicated that sourdough dough had a lower pH and higher total titrable acidity compared with yeast group. The texture of sourdough-steamed bread was significantly improved with reduced hardness and enhanced springiness. Microstructure revealed that sourdough resulted in starch surface corrosion and less amylopectin recrystallization. Aldehydes, alcohols, and esters are more dominant in sourdough group than yeast group. Foxtail millet and sorghum steamed breads exhibited the highest performances in texture, flavor, and sensory evaluation. This could provide a theoretical basis for producing coarse cereal products with desirable quality.

Empirical and Theoretical Bases of Good Steamed Bread Production

Chinese steamed bread (CSB) is a main staple food in China, accounting for 40% of wheat flour usage in China. Due to its health benefits, CSB is gaining popularity across the world. In this review, the effects of gluten proteins (particularly glutenins and gliadins) on the quality of CSB are summarized from the literature. Requirements of appropriate rheological parameters in different studies are compared and discussed. Along with the increasing demand for frozen storage food, there are obvious increases in the research on the dynamics of gluten proteins in frozen dough. This review also summarizes the factors influencing the deterioration of CSB dough quality during frozen storage as well as effective measures to mitigate the negative effects.

Main factors affecting the starch digestibility in Chinese steamed bread

Chinese steamed bread (CSB) is one of the staple foods in China, although it has a high glycemic index (GI) value. Development of CSB with a slower starch digestibility is thus of great importance for the improvement of human health. Many factors are related to the starch digestibility in CSB. Most currently available strategies are focusing on the incorporation of other whole flours with high dietary fiber or polyphenols to reduce the starch digestibility. Although successful in reducing starch digestibility, the incorporation of these flours also deteriorated textural attributes and sensory characteristics of CSB. Much more strategies have been applied for the reduction of starch digestibility in breads, which should be further explored to confirm if they are applicable for CSB. This review contains important information, that could potentially turn CSB into a much healthier food product with slower starch digestibility.

Evolution of volatiles and quality of Chinese steamed bread during storage at different temperatures

The aim of this work is to investigate the evolution of volatiles and quality of CSB during 4 d of storage at 4 °C and 25 °C, respectively. Rapidly increasing hardness and decreasing resilience were observed in CSB after 1 d of storage at 4 °C. However, relative soft CSB was found after 1 d of storage at 25 °C as a result of the lower rate of retrogradation. Volatiles were monitored by gas chromatography-mass spectrometer. Significant (P < 0.05) decrease of 4 esters and 2-pentylfuran were observed with prolonged storage time for CSB stored at both 4 °C and 25 °C. PCA analysis indicated that the storage temperature of 4 °C was beneficial to remain CSB volatiles during long storage time (2-4 d). These findings might be beneficial to retain more volatiles and quality and finally extend shelf-life of CSB.

Substantiation of basic stages of gluten-free steamed bread production and its influence on quality of finished product

Development and introduction of high quality gluten-free products is one of the priorities of food industry. Feasibility of producing gluten-free steamed bread based on rice and corn flour using flaxseed, sunflower, sorghum and quinoa flour additives is proved in the article. Recommended ratios of flours are established: Frc:Ffs 95:5, Frc:Fsn 95:5, Fcn:Fqn 85:15, Fcn:Fsg 90:10. The parameters of dough kneading are studied and the influence of additives on relative elasticity, plasticity and resilience is established. Use of additives leads to a decrease in irreversible relative deformation of dough for 36 – 68% and relative plasticity for 16 – 18%, to increase of its elasticity relative resilience up to 2.3 times. Dough fermentation process is investigated. It is established that amount of carbon dioxide accumulated in gluten-free dough increases by 10 – 30%. Process of acid accumulation during fermentation is studied. A flow chart for the production of gluten-free steamed bread is proposed. The parameters for the production of gluten-free steamed bread were established and justified. Product is prepared in a single-phase method, adopted in practice of baking bread. The duration of dough mixing is 10 – 15 min, fermentation 20 – 35 min. Steam treatment is carried out under atmospheric pressure. Recommended steam processing time is 35 min for bread based on rice flour, 30 min for based on corn flour. In comparison with the traditional technological scheme, it is recommended to use a double boiler instead of an oven.