Induced Non-Enzymatic Browning of Soybean Meal. I. Effects of Factors Controlling Non-Enzymatic Browning on In Vitro Ammonia Release

Abstract

Non-enzymatic browning was tested as a means of suppressing degradation of soybean meal (SBM) by ruminal microbes in five trials with in vitro ammonia release as the response criterion. Treatments imposed on SBM included reducing sugar source (xylose, glucose, fructose and lactose), reducing sugar level (1, 3 and 5 mol/mol SBM-lysine), pH (6.5, 8.5 and 10.0), dry matter (DM) content (65, 70, 75, 80, 85 and 90%) and varying lengths of heating time (0 to 90 min) at 150 C. Samples heated under conditions that promoted non-enzymatic browning gave greater (P less than .01) ammonia release suppression that when SBM was heated without these treatments. Xylose was the most reactive sugar, but extended heating of SBM containing glucose, fructose or lactose resulted in ammonia release similar to xylose. Increasing sugar level from 1 to 5 mol/mol SBM-lysine caused linear decreases (P less than .01) in ammonia release for xylose, glucose and fructose, but not lactose. Ammonia release was higher (P less than .01) at pH 6.5 than pH 8.5 and 10.0, and higher (P less than .01) at pH 9.5 than pH 10.0. Rate of non-enzymatic browning decreased when samples containing greater than 80% DM were heated. These results are interpreted to show that controlled non-enzymatic browning may be effective for reducing ruminal degradation of SBM.

The Effect of Heat or Heat-Xylose Processing on Nitrogen Fractions and <I>in Situ</I>/<i>In Vitro</i> Ruminal and Post-Ruminal Protein Disappearance of Guar Meal

“…In the study of Tunce and Sacakli (2003), in which the effect of different levels of xylose (0.5, 1 and 2% of DM) on degradation of soybean and canola meals was studied, ruminal CP degradability (24 h incubation) was lower than the untreated sample (at the rate of 37-67% for soybean meal and 1-21% for canola meal). However, the effect of heat-reducing sugar such as xylose on the extent of ruminal protein degradation depends on feed type and the concentration of reducing sugar (Hashiba, 1982), moisture content, both treatment temperature and time applied (Cleale et al, 1987;Broderick et al, 1993), amount of lysine content and epsilon amino group of lysine (Windschitl and Stern, 1988).…”

Silage additives to reduce protein degradation during ensiling and evaluation of in vitro ruminal nitrogen degradability

“…Furthermore, reducing sugars, which are found in erythritol by‐products, are likely to form complexes with proteins when heated (Maillard reaction) and could therefore protect them against degradation (Cleale, Klopfenstein, Britton, Satterlee, & Lowry, 1987a). To prevent forage damage, silage should not be exposed to high temperatures but it would be interesting to find out if the ensiling process is long enough for Maillard reactions to occur at lower temperatures.…”

“…However, excessive concentration in tannins can become an antinutritional factor for animals and reduce ingestion (Frutos, Hervas, Giráldez, & Mantecón, 2004). Furthermore, reducing sugars, which are found in erythritol byproducts, are likely to form complexes with proteins when heated (Maillard reaction) and could therefore protect them against degradation (Cleale, Klopfenstein, Britton, Satterlee, & Lowry, 1987a).…”

The Effect of Time and Method of Storage on the Chemical Composition, Pepsin-Cellulase Digestibility, and Near-Infrared Spectra of Whole-Maize Forage

“…Changes in the structural carbohydrate content are related to the formation of Maillard reaction products, which interfere with these assays. Maillard reaction products are affected by the type, amount of nonstructural carbohydrates [28], heat [36], water activity [37], and pH [38]. In our experiment, although differences in the temperatures between storage methods were produced over time, the barn temperatures were not high enough to produce Maillard products in the forage samples and thus increased the structural carbohydrate contents of the barn-stored samples relative to the frozen samples.…”