Yellow and Black Soybean Pellet Degradation and Nutrients Hydrolysis During In Vitro Gastrointestinal Digestion

Constructing in-situ and real-time monitoring methods during soy sauce production by miniature fiber NIR spectrometers

The digestion rate of steamed soybean (DRSS), protease activity of koji (PAK) and formaldehyde nitrogen content of moromi (FNCM) are key indicators to monitor soy sauce production. Currently, monitoring these indicators relies on workers' experience, which can sometimes lead to low material utilization rates and even fermentation failures. Near-infrared spectra were collected during soybean steaming, as well as koji and moromi fermentation, using miniature fiber spectrometers. These spectra were optimized using four pretreatment methods, and regression models were constructed using PLS, iPLS, and Si-PLS. The evaluation of models in prediction sets was based on the correlation coefficient (Rp) and root mean square error (RMSEP). Results indicated that Rp = 0.9327, RMSEP = 4.37% for DRSS, Rp = 0.9364, RMSEP = 228 U/g for PAK, and Rp = 0.9237, RMSEP =0.148 g/100 mL for FNCM were obtained. The above results coupling with validation experiments demonstrated that the developed in-situ and real-time spectroscopy system could ensure high-quality soy sauce production.

Germination time and in vitro gastrointestinal digestion impact on the isoflavone bioaccessibility and antioxidant capacities of soybean sprouts

Soybeans' isoflavone content increases with germination; nevertheless, their bioaccessibility in the gastrointestinal system is limited. This study evaluated the influence of germination time (1, 3, 5, and 7 days) and in vitro gastrointestinal conditions on the isoflavone profile of soybean sprouts. The total isoflavones (4.07 mg/g) and the malonyl genistin (1.37 mg/g) had the highest contents on day 5 in the gastric phase. The highest isoflavone bioaccessibility was observed in daidzein, genistein, and glycitin. An increase in antioxidant capacity was found during germination (day 7 > day 5 > day 3); however, the same trend was not observed during in vitro digestion. In summary, the results indicate that soybean sprouts germinated for 5 days may be more beneficial for consumption since they have the highest and most readily absorbed levels of isoflavones. These data suggest that soybean sprouts may be a functional food that provides bioavailable antioxidants.

Formation and In Vitro Simulated Digestion Study of Gelatinized Korean Pine Seed Oil Encapsulated with Calcified Wax

Natural waxes have demonstrated exceptional potential as oil gels for saturated and trans fatty acids, but their application has been limited by issues such as temperature sensitivity, lack of stability and durability, and compatibility. In this study, three types of wax (Beeswax (BW), Rice bran wax (RBW), and Carnauba wax (CW)) were combined with calcium hydroxide to produce calcified wax. The calcified Korean pine seed oil gel obtained by heating and stirring with Korean pine seed oil is responsive to temperature and has environmental adaptability. The effects of critical gel concentration, temperature regulation, texture properties, microstructure, oil-holding capacity, and FT-IR on the quality parameters of oil gel were investigated. Additionally, an in vitro digestion model was developed to comprehend the decomposition rate of fat during gel structure digestion and transportation. The results demonstrated a close correlation between the critical gelation concentration and calcium ion content. Furthermore, after calcification, the hardness followed the order BW > CW > RBW. Moreover, there was an approximate 10 °C increase in wax melting point. Conversely, BW:Ca exhibited the lowest oil leakage. The microstructures revealed that the oil gels formed post-wax calcification exhibited similar fractal dimension (Db) values (<7 μm), and the intermolecular forces were characterized by van der Waals forces, which were consistent with those observed in the non-calcified group. In conjunction with the vitro digestion simulation, our findings demonstrated that RBW and CW oil gels gradually released 20%, 35%, and 35% of free fatty acids (FFA) within the initial 30 min of intestinal digestion. Importantly, the FFA release rate was significantly attenuated, thereby providing a foundation for developing wax-based gel processed foods that facilitate gentle energy release benefits for healthy weight management.