Nucleotides inclusion in pet food: effect of thermic treatment and shelf-life

A growing trend of nucleotides supplementation in pets is occurring in recent years with the final goal of reinforcing the immune system and promoting intestinal function. Despite that, data evaluating possible alterations of nucleotides during pet food processing are lacking. The aim of the study was to evaluate the recovery percentage of nucleotides in dry and canned food after processing and storage. Selected dry and canned feed were supplemented with 0.4/100 g dry matter basis of Prosol petMOD™. Recovery percentage in dry food was 75% and 74% at the end of technological process and a 12-month shelf-life, while in canned food it was 43% and 41%, respectively. These results support the hypothesis that N could be included during pet food process but industries have to increase the awareness about possible losses, especially in canned food.


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In recent years there has been an increase in nucleotides supplementation, in particular in baby food 26 and in parenteral preparations, as numerous researches have demonstrated that including nucleotides 27 in such products lead to a reinforcement of the immune system and to a healthier gut in the receiver 28 [1]. 29 Nucleotides should be considered as "semi-essential" nutrients. It means that, in maintenance 30 condition the endogenous production satisfy requirements while in puppies and in course of tissue 31 damages, the exogenous administration is needed.

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De novo synthesis of nucleotides is a metabolically costly process requiring substantial amounts of 38 energy in the form of ATP [2]. Another mechanism for maintaining the cellular nucleotide pools is   after addicting water and steam, undergo a short but intense heating and mechanical treatment. To 65 guarantee storage at room-temperature, dry pet food is then dehydrated in stoves for 20-50 minutes.

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This industrial process, during which food components are exposed to high temperatures, could lead 67 to a degradation of all heat-sensitive and easily oxidable nutrients. [14].

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From a technological point of view, the canned pet food is considered a preserved one with a pH 69 close to neutrality; to guarantee its microbiological, chemical and physical stability and a prolonged

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The aim of the present work was to study nucleotides inclusion in a dry and a canned pet food, 74 determining their recovery percentage at the beginning and at the end of the technological production 75 and after a 12-month shelf-life, in order to underline, whether or not, these components could 76 experiment significant degradation after heating and prolonged storage.  Table 1. A commercial cat-pate formulation, whose chemical composition is show in Table 3, was prepared 97 with a Prosol petMOD ™ percentage of inclusion of 0.4 g/100 on raw materials. Table 4  108 Table 4. Operation preformed on canned food during phase 1 and relative temperature and duration 109 time.

Preparation of the main ingredients mixture 10
Inclusion of nucleotides with vitamin premix and gelling agents by dispersion in process water.  ]. The best way to achieve a dietary integration of nucleotides is to add them directly to a 143 commercial food, even if the main source of these elements for healthy subjects is usually represented 144 by meat and its by-product, which represent one of the main components of their maintenance diet.

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Despite the beneficial function of nucleotides administration is well recognized, little is still known 146 about the capability of these elements to resist to technological processes. The present study was 147 conducted to improve the knowledge in this field. The technological process for dry food wasn't able to significantly degrade raw materials leading to 165 a higher recovery percentage as compared to moist food and a stable concentration during the 12-166 months shelf-life. This finding could be explained considering that during food production 167 temperatures reached at the product core were lower than in canned food.

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In conclusion, nucleotides are raw materials authorized by Reg 01491-EN for inclusion in pet food 170 that demonstrate different resistance to production process in dry or canned food. Pet food industries 171 have to increase their awareness about this aspect, in order to ensure sufficient levels of nucleotides 172 in the finished product able to exert beneficial effects on immune function and gastrointestinal system.

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Further studies are still warranted to optimize recovery percentage after inclusion in canned food and 174 to evaluate their stability after a longer shelf-life period (i.e. 24 and 48 months).

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Declaration of interest 176 The authors declare that there is no conflict of interest that could be perceived as prejudicing the 177 impartiality of this manuscript.