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The nutritional value or quality of dietary proteins used for poultry feed formulation varies: amino acid availability is an important measure of protein quality. Determination of ileal digestibility values has become the preferred method for estimating amino acid availability. This review discusses the different approaches to the expression of digestibility results, including correction for endogenous loss and the derivatisation of standardised values. Sources of variation in values include, the assay protocol, anti-nutritional factors in feedstuffs and feed milling. Feed formulating with ileal digestibility values should allow higher dietary inclusion levels of protein feedstuffs of lower quality provided that values of different feedstuffs are additive, the age of the bird and the use of feed enzymes are considered. An Australian data set of "ileal digestible amino acid values in feedstuffs for poultry" that has recently be published is described. This overview is intended to stimulate interest in the generation and application of ileal digestibility as a method for estimating amino acid availability in poultry nutrition.O valor nutritivo ou a qualidade das proteínas dietéticas utilizadas para a formulação de rações para aves varia: a disponibilidade de aminoácidos é uma medida importante da qualidade da proteína. A determinação dos valores de digestibilidade ileal tornou-se o método preferido para a estimativa da disponibilidade de aminoácidos. Nesta revisão são discutidas as diferentes abordagens para a expressão dos resultados de digestibilidade, incluindo a correção de perdas endógenas e a derivação de valores padronizados. As fontes de variação dos valores incluem o protocolo do ensaio, os fatores anti-nutricionais na alimentação e a indústria de alimentação. A formulação de rações com base nos valores de digestibilidade ileal deve permitir a inclusão de maiores níveis dietéticos de alimentos com proteína de qualidade inferior, desde que sejam considerados os valores dos diferentes alimentos aditivos, a idade da ave e o uso de enzimas para alimentação animal. Um conjunto de dados australianos de "valores de aminoácidos digestíveis ileais em alimentos para aves" acaba de ser publicado. Esta visão procura estimular o interesse na geração e aplicação de digestibilidade ileal como um método para estimativa da disponibilidade de aminoácidos na nutrição de aves.

Sweet potato starch (SPS) was modified by dry heat and short-chain inulin (SI). The influences on physiochemical properties of SPS were explored. Subsequently, the changes in structural characteristics were analyzed. Dry heating made the viscosity parameters increase, pasting temperature and ΔH value reduce, and raised the texture parameters except cohesiveness of SPS. Dry heating with SI remarkably reduced BD and SB of SPS than those of the dry heated samples without SI. Both To and Tc of the dry heated SPS-SI mixture were lower than those of the native SPS. Dry heating with SI improved solid-like characteristics of SPS pastes, and resulted in the increase of the larger particle size of SPS. Adhesive matters could be found on the surface of dry heated SPS-SI mixture. The degree of crystallinity decreased, while the crystallinity type remained unchanged after dry heat treatment with SI.

The influences of inulin on pasting, textural, and rheological properties of sweet potato starch (SPS) were explored. Subsequently, the interactions between inulin and SPS were analyzed. Results showed that inulin could make the pasting temperature increase and all viscosity parameters of SPS-inulin blends decline. With the increased inulin, SPS gel hardness decreased; while both springiness and resilience first increased and then decreased, and reached to the maximum at an addition level of 5%. SPS-inulin blends paste displayed a pseudoplastic and shear-thinning property. Results of dynamic viscoelasticity indicated that inulin improved liquid-like characteristics of SPS-inulin blends pastes, and temperature of G’ Max, G’’Max increased with the increase in inulin. Additionally, the swelling of SPS granules was obviously inhibited by inulin, and granules were mostly concentrated in the smaller. Inulin also greatly decreased the leached amylose content (p < 0.05). The interaction between SPS and inulin was the hydrogen bond.