Green banana flour as a novel functional ingredient in retorted feline diets

Abstract

Green banana flour (GBF) is a novel ingredient that is high in resistant starch and could be a dietary fiber source in companion animal nutrition. In addition, with its light brown color and pectin content, GBF could potentially serve as a natural color additive and thickening agent in pet food manufacturing. The purpose of this research is to evaluate different sources of GBF, the effect of GBF on texture and color in canned foods, and its effect on apparent total tract digestibility (ATTD), fecal characteristics, and fecal fermentative end-products in healthy adult cats. Prior to the feline study, different sources of GBF were analyzed for chemical composition, manufacturing properties, true metabolizable energy, and fermentability. For the feline feeding trial, all treatment diets were formulated to meet or exceed the Association of American Feed Control Officials (Association of American Feed Control Officials (AAFCO) 2020. Official Publication. Champaign, IL.) guidelines for adult cat maintenance. There were five dietary treatments: rice control (4% rice flour), potato control (4% dehydrated potato flakes), 1% GBF (1% GBF and 3% rice flour), 2% GBF (2% GBF and 2% rice flour), and 4% GBF. All treatment diets were analyzed for texture and color. The animal study was conducted using a completely randomized design with 39 adult domestic cats. There was a 7-d diet adaptation period followed by a baseline fresh fecal collection to determine fecal score, pH, short-chain fatty acid, branched-chain fatty acid, phenol, indole, ammonia, and microbiota. The treatment period lasted for 21 d and a total fecal collection was performed during the last 4 d of this period to determine the ATTD. A fresh fecal sample was also collected during the total fecal collection to evaluate fecal score, pH, metabolites, and microbiota. The MIXED model procedures of SAS version 9.4 were used for statistical analysis. Treatment diets containing GBF had a lower hardness from the texture profile analysis (P < 0.05). For color analysis, the 4% GBF diet was darker in color compared with the rice diet (P < 0.05). There was no difference in food intake, fecal output, or ATTD of macronutrients among the treatment groups (P > 0.05). There was no interaction of treatment and time or main effects shown in fecal score, pH, metabolites, or microbiota diversity (P > 0.05). In conclusion, adding GBF to canned diets may affect the texture and color of the product, but GBF was comparable to traditional carbohydrate sources, rice, and potato, from a nutritional aspect.

Keywords: cats; color; green banana flour; nutrient digestibility; resistant starch; texture.

Figure 1.

True metabolizable energy corrected to zero nitrogen retention of different sources of green banana flour (GBF). GBF1, Pereg Banana Multi-purpose Flour; GBF2, Duraci Farinha de Banana Verde; GBF3, Let’s Do Organic GBF; GBF4, Peterson Dried Banana. No treatment effect was observed (P > 0.05).

Figure 2.

Short-chain fatty acid production and pH change during the in vitro fermentation experiment for green banana flour. * Mean values are significantly different among treatments (P < 0.05).

Figure 3.

Consistency of the treatment diet batter containing traditional starch source and green banana flour measured by distance traveled in Bostwick Consistometer. ^a-c Means with different superscript letters are different (P < 0.05).

Figure 4.

Phylum composition of fecal microbiota from adult felines fed dietary treatments containing traditional starch source and green banana flour.

Figure 5.

Family composition of fecal microbiota from adult felines fed dietary treatments containing traditional starch source and green banana flour.

Figure 6.

Genus composition of fecal microbiota from adult felines fed dietary treatments containing traditional starch source and green banana flour.