As part of studies of residues and unintended effect studies of pesticides, analyses on processed foods must be carried out in accordance with European, OECD and EPPO regulations. The Staphyt food processing laboratory, which has certifications in GEP and GLP, conducts a wide variety of agri-food processing as close as possible to industrial techniques. The laboratory is located in France and receives all types of products sampled worldwide in order to prepare oily, aqueous, acidic and fermented matrices for analysis.
With approximately 65 kg per person per year on average, rice is one of the most widely consumed cereals in the world, alongside wheat (67 kg per person per year), followed by maize (23 kg per person per year), and other cereals like barley, oats, and rye (according to the Food and Agriculture Organization of the United Nations). Like all crops, rice faces constant threats such as insects, fungi, and bacterial diseases. It represents a significant challenge for phytosanitary companies in the fight against these potential threats.
It is within the framework of the development and registration of these products that Staphyt’s food processing laboratory located in France has initiated new studies. Residue studies of phytosanitary products have been conducted on various rice-derived processed products such as polished rice, flour, rice oil, pre-cooked rice, and sake.
How to make Sake ?
We will focus, in this article, on the sake-making process. The study of residues in sake provides a wider variety of processed products made from rice. A new process that began in 2023, the making of sake has been a great learning experience for our technical team.
Sake is a traditional Japanese alcoholic beverage consumed like wine. Its production involves several transformation steps. The various stages and techniques can vary among producers and types of sake, resulting in a wide variety of flavours and sake styles.
The first and most important step is rice polishing (Seimai-buai): after being carefully cleaned, the rice is polished to remove the outer layer, leaving only the central part of the grain. The degree of rice polishing determines the final quality of the sake.
The rice is then washed to remove dust and dirt and soaked (Mizumawari) in water to hydrate it. This step allows the rice to absorb the necessary water for fermentation.
After washing, the rice is steam-cooked (Koji-Kin). This is a crucial step as it affects the texture and flavour of the final sake.
Rice during the Koji phase
A portion of the cooked rice is set aside to be inoculated with koji spores (Koji-Zukuri), a specific fungus. Koji is essential for converting the rice starch into sugar during fermentation.
The progressive development of aspergillus oryzae (the koji spore)
The other portion of the cooked rice is mixed with water and yeast to create a mixture called “moto” (Moromi). Moto serves as the yeast source for alcoholic fermentation. Moto is added to the rice and koji mixture, creating the mash. This mash ferments (Yeast sakaba) for several weeks at a low temperature, converting sugar into alcohol.
After fermentation, the mash is pressed (Yabuta) to separate the clear alcoholic liquid from the remaining solids. The obtained liquid is called raw sake.
Filtration to monitor fermentation progress
Raw sake typically undergoes filtration to remove impurities. It can also be pasteurised to kill bacteria and stop fermentation.
Sake is often aged for several months to several years to develop its aromas and flavours before being served.
Our GLP-certified team then takes samples to analyse the rice processed into sake, to measure residues. This analysis is used to complete the registration dossier.
For residues studies, you can contact our business development managers on GLP trials:
Célia Bastiani
GLP field trials
+33 (0)6 12 99 30 09
Giampiero Flaminio
GLP laboratory studies
+39 345 087 6029